Model Library

7/29/2019 Model Library

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Overview of Model Library

This topic describes the five main groups of library models in the Aspen Adsorption library.

These are:

Gas ModelsThe table lists the gas phase models available in Aspen Adsorption. You connect these models usingthe gas_Material Connection.

gas_bed Model

The gas_bed model simulates an adsorption bed unit in a gas flowsheet. It acts like a container modelfor the bed layers and their interconnections.

See Also

gas_bed Model: Connectivity

gas_bed Model: Configuration

Group Description

Adsorption_Gas Gas phase flowsheet models

Adsorption_gCSS Gas cyclic steady-state flowsheet models.

Adsorption_IonX Ion-exchange flowsheet models

Adsorption_Liquid Liquid phase flowsheet models

Miscellaneous Additional flowsheet models that require noconnectivity

Model Description

gas_bed Adsorbent bed layers

gas_buffer_interaction Tank with inlet delay capabilities

gas_feed Feed/inlet boundary terminator

gas_heat_exchanger General instantaneous heat exchanger (optional

liquid condensate stream)gas_interaction Pseudo bed for single bed approach

gas_node Simple multi-stream meeting point

gas_pipe simple instantaneous pipe

gas_product Product/outlet boundary terminator

gas_pump Compressor or vacuum pump

gas_ramp Special model for forced pressure profiles

gas_tank_void General purpose model to account for spaces andholdup

gas_valve Relates pressure drop to flowrate

页码，1/119Overview of Model Library

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gas_bed Model: Specifications

gas_bed Model: Initialization

gas_bed Model: User Procedures Used

gas_bed Model: Results

gas_bed Model: Additional Notes

gas_bed Model: Connectivity

These are the available connections for the gas-bed model:

gas_bed Model: Configuration

These are the configuration options available for the gas_bed model:

Port Name Type Valid ConnectionProcess_In g_material_port (single) gas_Material_Connection

Process_Out g_material_port (single) gas_Material_Connection

Option Valid Values Description Number of layers Integer (1 or higher) Number of independent

adsorbent layers with the bed

Bed type Vertical

Horizontal

Radial

Orientation and configuration of the adsorbent layer/s

Spatial Dimensions 1-D

2-D

Number of spatial dimensions to

account for within eachadsorbent layer (valid only for vertical geometries)

Internal heat exchanger None

1-Phase, internal

1-Phase, jacket

Steam-Water, internal

Steam-Water, jacket

Heat exchange equipment within

the adsorbent layers, or at theexternal surface





gas_bed Model: Specifications

Depending on how the gas_bed model has been configured, you need to specify one or more of thesevariables in the Specify table:

Note Each adsorbent layer within the bed has its own specifications.

gas_bed Model: Initialization

No initialization method is required for the gas_bed model. Each contained layer, however, needs to

be initialized accordingly.

gas_bed Model: User Procedures Used

There are no user procedures available for the gas_bed model.

gas_bed Model: ResultsTypical variables in the Results table for the gas_bed model are:

Variable DescriptionMFlow Mass flowrate of heating/cooling medium

Cp Specific heat capacity of heating/cooling medium

Taux_In Inlet temperature of heating/cooling medium

Taux_Out Outlet temperature of Heating/cooling medium

MFlowcw Mass flowrate of cooling water

Cpcw Heat capacity of cooling water

Tcw_In Inlet temperature of cooling water

MFlowst_in Mass flowrate of steam

Cpst Heat capacity of steam

Tst_In Steam inlet temperature

Lambda Steam heat of condensation

Variable Description

E Total energy transferred to the environment

ECyc Total energy transferred to the environment for the last cycle

EHx Total heat exchanged to single phase medium

EHxCyc Total heat exchanged to single phase medium for

the last cycleEcw Total heat exchanged to cooling water

EcwCyc Total heat exchanged to cooling water for the last





gas_bed Model: Additional Notes Note the following information when using the gas_bed model:

You can give a label or ID number for each adsorbent layer in the bed

The gas_bed model does not include any inlet or outlet dead space. Use a gas_tank_void

model at each end to simulate dead space.

The gas_bed model behaves as a reversible flow setter. Ideally, it expects a reversible pressure

setter to be connected at each end.

gas_buffer_interaction Model

The gas_buffer_interaction model simulates a void or tank where material can accumulate. Use the

model as part of the single bed modeling approach to simulate, for example, material recovered froma pseudo bed whilst the actual modeled bed undergoes a regenerative step.

See Also

gas_buffer_interaction Model: Connectivity

gas_buffer_interaction Model: Configuration

gas_buffer_interaction Model: Specifications

gas_buffer_interaction Model: Initialization

gas_buffer_interaction Model: User Procedures Used

gas_buffer_interaction Model: Results

gas_buffer_interaction Model: Additional Notes

gas_buffer_interaction Model: Connectivity

These are the available connections for the gas-buffer_interaction model:

cycle

Est Total heat exchanged to steam

EstCyc Total heat exchanged to steam for the last cycle

Port Name Type Valid Connection

Process_In g_material_port (single) gas_Material_Connection





gas_buffer_interaction Model: Configuration

These are the configuration options available for the gas_buffer_interaction model:

gas_buffer_interaction Model: SpecificationsDepending on how the gas_buffer_interaction model has been configured, you need to specify one or more of these variables in the Specify table:

Process_Out g_material_port (multiport) gas_Material_Connection

Option Valid Values Description

Model type Reversible Pressure Setter

Non-Reversible

Mode of flowsheet interactivity

Gas model assumption Ideal Gas

Fixed Compressibility

User Procedure Compressibility

User Submodel Compressibility

Is the gas contained an ideal gas?If not ,how is the compressibilityfactor supplied?

Include compression term Yes

No

Is the heat of compressionincluded in the energy balance?

Heat effect assumption Adiabatic

Non-Adiabatic

Is there heat exchange with theexternal environment?

Shape assumption Spherical

Cylindrical

Hemispherical

Cap

Unknown

If there is heat exchange with theexternal environment, what

shape is the heat transfer area?


Tank_Volume Total volume of the tank/void

Height Height of a cylindrical void/tank

Tank_Height Height from cap seam to apex

Diameter Diameter of cylinder/sphere/cap/hemisphere

Surface_Area Overall surface area through which heat isexchanged

Z Constant gas compressibility factor





gas_buffer_interaction Model: Initialization

The recommended variables to preset and initialize for the gas_buffer_interaction model are:

A valid alternative specification is:

To run the initialization script contained within the model, click the Initialize button or select Check & Initial from the Flowsheet menu. This calculates the appropriate molar holdup for the conditions

provided.

gas_buffer_interaction Model: User

Procedures Used

Mass_Shell Mass of void/tank wall

Cp_Shell Heat capacity of the shell wall

HTC_Shell Heat transfer coefficient between internal gas andwall

HTC_Env Heat transfer coefficient between wall and theenvironment

T_Shell Shell wall temperatureT_Env Environment temperature

Delay_Initial_Reverse_F For a reverse interaction, the estimated flowrate touse for the first cycle

Delay_Initial_Reverse_Y For a reverse interaction, the estimated

composition to use for the first cycle

Delay_Initial_Reverse_H For a reverse interaction, the estimated enthalpyto use for the first cycle

Variable Specification Description

Y Free (preset) Internal molefraction

composition

T Initial Internal temperature

P Free (preset) Internal pressure

Mc Initial Internal molar holdup (found inResults table)


Y Initial (ncomps-1)

Free (preset, 1 comp)

Internal molefractioncomposition


P Initial Internal pressure

Mc Free (preset) Internal molar holdup (found inResults table)





Depending on how the gas_buffer_interaction model is configured, the user procedures available are:

gas_buffer_interaction Model: Results

Typical variables in the Results table for the gas_buffer_interaction model are:

gas_buffer_interaction Model: AdditionalNotes

Note the following information when using the gas_buffer_interaction model:

Use the Cycle Organizer to define the interactions between steps.

By default, the model behaves as a reversible pressure setter.

gas_feed Model

The gas_feed model terminates an inlet/feed flowsheet boundary. Use it to specify the material

composition, temperature and pressure. If configured as reversible, the model acts as a product sink should the flow reverse.

See Also

gas_feed Model: Connectivity

gas_feed Model: Configuration

gas_feed Model: Specifications

gas_feed Model: Initialization

User Procedure Description

pUser_g_Enthalpy_Mol Molar enthalpy (user Fortran physical properties)

pUser_g_Compressibility Compressibility factor (user Fortran physical properties)


Y Internal holdup composition

Mc Internal component holdup

T Internal temperatureP Internal pressure

H Internal enthalpy





gas_feed Model: User Procedures Used

gas_feed Model: Results

gas_feed Model: Additional Notes

gas_feed Model: Connectivity

This is the available connection for the gas_feed model:

gas_feed Model: Configuration

These are the configuration options available for the gas_feed model:

gas_feed Model: Specifications

Depending on how the gas_feed model has been configured, you need to specify one or more of these variables in the Specify table:





Non-Reversible


Enable reporting True

False

Enable boundary accumulation

terms for material balancereporting

Variable Description Reversible/Non-reversible model

Y_Out Composition of stream Non-reversible model

T_Out Temperature of stream Non-reversible model

P_Out Pressure at boundary Non-reversible model

Y_Fwd Composition of stream inforward direction

Reversible model

T_Fwd Temperature of stream inforward direction

Reversible model

P Pressure at boundary Reversible model





gas_feed Model: Initialization

No initialization method is required.

gas_feed Model: User Procedures Used

Depending on how the gas_feed model is configured, the user procedure available is:

gas_feed Model: ResultsTypical variables in the Results and Reports table for the gas_feed model are:



Variable Description Reversible/Non-reversible model

F_Out Molar flowrate Non-reversible model

F Molar flowrate Reversible model

Y_Rev Stream composition in reversedirection

Reversible model

T_Rev Stream temperature in reverse

direction

Reversible model

H_Rev Stream enthalpy in reverse

direction

Reversible model

Total_Material Total material fed into boundary Non-reversible model

Total_Material_Fwd Total material fed into boundary Reversible model

Total_Material_Rev Total material received at boundary

Reversible model

Total_Component Total component fed into boundary

Non-reversible model

Total_Component_Fwd Total component fed into

boundary

Reversible model

Total_Component_Rev Total component received at boundary

Reversible model

Avg_Composition Total average composition of component fed into boundary


Avg_Composition_Fwd Total average composition of

component fed into boundary

Reversible model

Avg_Composition_Rev Total average composition of component received at boundary

Reversible model

Total_Energy Total energy fed into boundary Non-reversible model

Total_Energy_Fwd Total energy fed into boundary Reversible model

Total_Energy_Rev Total energy received at boundary

Reversible model

Cycle_Total_Material Total material fed into boundary Non-reversible model





gas_feed Model: Additional Notes

Note the following information when using the gas_feed model:

For forced feed (that is, fixed material flowrate, no valve fitted to the outlet), it is valid tospecify F_Out or F_Fwd as Fixed.

At low flow conditions where the absolute value of the flowrate is less than or equal to theresidual tolerance, the information in the Report table is inaccurate.

gas_heat_exchanger Model

The gas_heat_exchanger model modifies the temperature of an inlet stream. By default, it operates ata constant outlet temperature. You can change the model operation to either constant duty or constant temperature rise/drop. The model is of type non-reversible.

See Also

gas_heat_exchanger Model: Connectivity

for last cycle

Cycle_Total_Material_Fwd Total material fed into boundaryfor last cycle

Reversible model

Cycle_Total_Material_Rev Total material received at boundary for last cycle

Reversible model

Cycle_Total_Component Total component fed into

boundary for last cycle


Cycle_Total_Component_Fwd Total component fed into boundary for last cycle

Reversible model

Cycle_Total_Component_Rev Total component received at boundary for last cycle

Reversible model

Cycle_Avg_Composition Total average composition of

component fed into boundary for last cycle


Cycle_Avg_Composition_Fwd Total average composition of component fed into boundary for last cycle

Reversible model

Cycle_Avg_Composition_Rev Total average composition of component received at boundaryfor last cycle

Reversible model

Cycle_Total_Energy Total energy fed into boundaryfor last cycle


Cycle_Total_Energy_Fwd Total energy fed into boundaryfor last cycle

Reversible model

Cycle_Total_Energy_Rev Total energy received at


Reversible model





gas_heat_exchanger Model: Configuration

gas_heat_exchanger Model: Specifications

gas_heat_exchanger Model: Initialization

gas_heat_exchanger Model: User Procedures Used

gas_heat_exchanger Model: Results

gas_heat_exchanger Model: Connectivity

These are the available connections for the gas_heat_exchanger model:

gas_heat_exchanger Model: Configuration

No configuration options are available for the gas_heat_exchanger model.

gas_heat_exchanger Model: Specifications

Depending on how the gas_heat_exchanger model has been configured, you need to specify one or

more of these variables in the Specify table:

as heat exchan er Model: Initialization

Port Name Type Valid ConnectionProcess_In g_material_port (single) gas_Material_Connection


Liquid_Out liq_material_port (single,

optional)

liq_Material_Connection


Heat_Exchange_Area Composition of stream (non-reversible model)

U Overall heat transfer coefficient

T_Out Outlet temperature

T_Fluid Temperature of heat exchange fluid

Q Heat exchanger duty

T_Change Temperature rise/drop of process stream

P_Drop Constant average pressure drop





No initialization method is required for the gas_heat_exchanger model.

gas_heat_exchanger Model: User Procedures

UsedDepending on the model configuration, the user procedures available for the gas_heat_exchanger model are:

Note: All these procedures are user-Fortran physical properties, with the optional liquid portconnected.

gas_heat_exchanger Model: Results

Typical variables in the Specify table for the gas_heat_exchanger model are:

gas_interaction Model

Use the gas_interaction model as part of the single bed modeling approach, to record the profile of material received, then later replay this profile to simulate returned material. The following arerecorded over time:

Molar flowrate

Mole fraction composition

Temperature

Upstream (bed) pressure

Specific enthalpy

By acting as a pseudo-adsorbent bed, the model can behave as a bed at either constant or varying


pUser_g_Enthalpy_Mol Molar enthalpy

pUser_g_Avg_Mole_Weight Average molecular weight

pUser_l_Density_Mass Overall liquid density

pUser_Flash Instantaneous flash calculation enthalpy

Variable DescriptionT_Out Outlet temperature


T_Change Temperature rise/drop





pressure. Use the Cycle Organizer to define the steps between which an interaction occurs.

You can define any type of bed interaction with the model:

Top-to-top

Top-to-bottom

Bottom-to-bottom

Bottom-to-top

These are defined by the connectivity, that is where material is accepted from and returned to.Interactions cannot be redefined during a run as connectivity is structural, so if you want more thanone type of interaction, use additional interaction models.

In the first cycle, during cyclic operation, the model uses an approximation based on an assumed

effective volume, to simulate the pressure of the interacting bed. For subsequent cycles, the recorded pressure profile of the rigorously modeled bed provides an accurate response for the pseudo bed.

See Also

gas_interaction Model: Connectivity

gas_interaction Model: Configuration

gas_interaction Model: Specifications

gas_interaction Model: Initialization

gas_interaction Model: User Procedures Used

gas_interaction Model: Results

gas_interaction Model: Additional Notes

gas_interaction Model: ConnectivityThese are the available connections for the gas_interaction model:

gas_interaction Model: ConfigurationThese are the configuration options available for the gas_interaction model:








gas_interaction Model: Specifications

Depending on how the gas_interaction model has been configured, you need to specify one or moreof these variables in the Specify table:

Note: All these variables are used in the first cycle

gas_interaction Model: Initialization

No initialization method is required for the gas_intaraction model.

gas_interaction Model: User Procedures Used

Depending on the model configuration, the user procedure available for the gas_interaction model is:

gas_interaction Model: Results

Option Valid Values Description Comment

Delay behaviour v10xv6x

Assumption used for subsequent cycles

Use real profile or continue with estimated

profile

FIFO profile TrueFalse

Type of profile buffer used

Standard first-in-first-out, or inverted first-in-

last-out


Notional_Volume Estimated effective volume of the real bed/sP_Stage_Start Start pressure of the interaction unit

XFac Effective volume correction factor

F_Initial_Reverse Average flowrate of returned material during areverse interaction

Y_Initial_Reverse Average composition of returned material duringa reverse interaction

T_Initial_Reverse Average temperature of material during a reverse

interaction

P_Initial_Reverse Average pressure of returned material during areverse interaction


pUser_g_Enthalpy_Mol Molar enthalpy (user Fortran physical properties,optional liquid port not connected)





The typical variable in the Results table for the gas_interaction model is:

gas_interaction Model: Additional Notes

Note the following information when using the gas_interaction model:

The model assumes that standard unit operation is a first-in-first-out buffer profile. For specialist applications, you can invert this profile, but this is a structural parameter so your new profile applies to all interactions in a unit.

If the buffer profile is assumed first-in-last-out, the delay behavior uses estimated pressure

profiles for all cycles.

The communication interval affects model accuracy. If interactions are present, try to have atleast three communication points within the shortest interacting steps.

The model uses a Delay function. Exiting Aspen Adsorption, loading a new problem or reopening the old problem, all clear the delay buffer so historical information is lost.

By default, the approximation or initial reverse values are only used in the first cycle. You canapply these to all cycles by changing the delay behavior to v6x.

Each interaction unit can handle multiple interacting pairs.

Use the Cycle Organizer to define the interaction and profile times.

For the unit inlet stream, use a gas_valve or gas_ramp model; for the outlet, connect anymodel except a gas_valve or gas_ramp. (The Check & Initial option in the Flowsheet menu

detects errors here and corrects accordingly.)

The model approximates the pressure in the interaction unit using:

Click the Estimate button on the configure form for an approximate value for

Notional_Volume. This calculation uses the interstitial volume of the gas_bed train present onthe flowsheet.

The variables Notional_Volume, P_Stage_Start, XFac, F_Initial_Reverse, Y_Initial_Reverse,T_Initial_Reverse and P_Initial_Reverse are used only in the first cycle. They are ignored insubsequent cycles.

Within the Cycle Organizer, reset P_Stage_Start to the required value for each step. Pressurechanges then start from this value.

XFac may need modifying from step to step. To do this, use the Cycle Organizer.


P Internal pressure





To simulate a constant pressure interaction, set XFac to a high value, such as 100. This

increases the volume to such an extent that it acts like a void of near infinite capacity.

gas_node Model

The gas_node model joins one or more inlet streams to one or more outlet streams. The model is analternative method to the gas_tank_void model for joining multiple streams, but without an internalvolume.

See Also

gas_node Model: Connectivity

gas_node Model: Configuration

gas_node Model: Specifications

gas_node Model: Initialization

gas_node Model: User Procedures Used

gas_node Model: Results

gas_node Model: Additional Notes

gas_node Model: Connectivity:

These are the available connections for the gas_node model:

gas_node Model: Configuration

This is the configuration option available for the gas_node model:


Process_In g_material_port (multiport) gas_Material_Connection




Non-Reversible






gas_node Model: Specifications

There are no variables to specify for the gas_node model.

gas_node Model: Initialization

No initialization method is required for the gas_node model.

gas_node Model: User Procedures Used

Depending on the model configuration, the user procedure available for the gas_node model is:

gas_node Model: Results

Typical variables in the Results table for the gas_node model are:

gas_node Model: Additional Notes

Note the following information when using the gas_node model:

For robustness, use the gas_tank_void model as a common meeting point.

To avoid indeterminate variables, ensure a pressure setter is connected to a single inlet or outlet.

gas_pipe ModelUse the gas_pipe model to simulate a simple, flowing isothermal gas pipe. The pipe is assumed to




Y Average composition of outlet material

T Average temperature of outlet material

P Common pressure of node

H Average enthalpy of outlet material





have negligible hold-up volume so that it responds instantaneously to any change in the inflowing

stream. The model acts as a flow setter. The constant density assumption is generally acceptable for short pipes whose pressure drop is less than 10% of the total inlet pressure.

See Also

gas_pipe Model: Connectivity

gas_pipe Model: Configuration

gas_pipe Model: Specifications

gas_pipe Model: Initialization

gas_pipe Model: User Procedures Used

gas_pipe Model: Results

gas_pipe Model: Additional Notes

gas_pipe Model: Connectivity

These are the available connections for the gas_pipe model:

gas_pipe Model: Configuration

These are the configuration options available for the gas_pipe model:

gas_pipe Model: Specifications

Depending on how the gas_pipe model has been configured, you need to specify one or more of these variables in the Specify table:


Process_In g_material_port (single) gas_Material_ConnectionProcess_Out g_material_port (single) gas_Material_Connection



Non-Reversible


Gas Density along pipe Varying

Constant

Density variation within the pipe





gas_pipe Model: Initialization

No initialization method is required for the gas_pipe model.

gas_pipe Model: User Procedures Used

Depending on the model configuration, the user procedures available for the gas_pipe model are:

gas_pipe Model: Results

Typical variables in the Results table for the gas_pipe model are:

gas_pipe Model: Additional Notes Note the following information when using the gas_pipe model:

You must supply a constant, non-zero value for the pipe friction factor. This is reasonable for fully developed turbulent flow, for which the friction factor is independent of flow rate.Typically, the friction factor varies between about 0.002 and about 0.02.

You can either:

specify the pipe pressure drop or outlet pressure to calculate flow rate

-Or-

make the pressure drop free and have it calculated from the molar flow rate


Dia Pipe dimeter

L Length of pipe

FF Friction factor



pUser_g_Avg_Mole_Weight Average molecular weight of gas (user Fortran

physical properties)


AMW Average molecular weight of gas

DP Pressure drop along the pipe





gas_product Model

The gas_product model terminates an outlet/product flowsheet boundary. It receives material fromthe flowsheet. If configured as a reversible model, the model acts as a feed unit should the flowreverse. The material composition and temperature for this material can be defined.

See Also

gas_product Model: Connectivity

gas_product Model: Configuration

gas_product Model: Specifications

gas_product Model: Initialization

gas_product Model: User Procedures Used

gas_product Model: Results

gas_product Model: Additional Notes

gas_product Model: ConnectivityThese are the available connections for the gas_product model:

gas_product Model: Configuration

These are the configuration options available for the gas_product model:





Non-Reversible



False

Enable boundary accumulationterms for material balancereporting





gas_product Model: Specifications

Depending on how the gas_product model has been configured, you need to specify one or more of these variables in the Specify table:

gas_product Model: Initialization

No initialization method is required for the gas_product model.

gas_product Model: User Procedures Used

Depending on the model configuration, the user procedure available for the gas_product model is:

gas_product Model: Results

Typical variables in the Results and Reports tables for the gas_product model are:

Variable Description Reversible/Non-ReversibleModel

P_In Pressure at boundary Non-reversible model

Y_Rev Composition of stream in reversedirection

Reversible model

T_Rev Temperature of stream in reversedirection

Reversible model



pUser_g_Enthalpy_Mol Molar enthalpy (user Fortran physical properties,

reversible model)


F_In Molar flowrate Non-reversible model

F Molar flowrate Reversible model

Y_Fwd Stream composition Reversible model

T_Fwd Stream temperature Reversible model

H_Fwd Stream enthalpy Reversible model

Total_Material Total material received at boundary


Total_Material_Fwd Total material received at boundary

Reversible model

Total_Material_Rev Total material fed into boundary Reversible model





gas_product Model: Additional Notes

Note the following information when using the gas_product model:

Total_Component Total component received at

boundary


Total_Component_Fwd Total component received at boundary

Reversible model

Total_Component_Rev Total component fed into boundary

Reversible model

Avg_Composition Total average composition of component received at boundary


Avg_Composition_Fwd Total average composition of component received at boundary

Reversible model

Avg_Composition_Rev Total average composition of component fed into boundary

Reversible model

Total_Energy Total energy received at boundary


Total_Energy_Fwd Total energy received at boundary

Reversible model

Total_Energy_Rev Total energy fed into boundary Reversible model

Cycle_Total_Material Total material received at boundary for last cycle


Cycle_Total_Material_Fwd Total material received at boundary for last cycle

Reversible model

Cycle_Total_Material_Rev Total material fed into boundaryfor last cycle

Reversible model

Cycle_Total_Component Total component received at boundary for last cycle


Cycle_Total_Component_Fwd Total component received at boundary for last cycle

Reversible model

Cycle_Total_Component_Rev Total component fed into boundary for last cycle Reversible model

Cycle_Avg_Composition Total average composition of component received at boundaryfor last cycle


Cycle_Avg_Composition_Fwd Total average composition of

component received at boundaryfor last cycle

Reversible model

Cycle_Avg_Composition_Rev Total average composition of component fed into boundary for last cycle

Reversible model

Cycle_Total_Energy Total energy received at boundary for last cycle


Cycle_Total_Energy_Fwd Total energy received at boundary for last cycle

Reversible model

Cycle_Total_Energy_Rev Total energy fed into boundary

for last cycle

Reversible model





At low flow conditions, where the absolute value of the flowrate is less than or equal to the

residual tolerance, the information in the Report table is innacurate.

gas_pump Model

The gas_pump model simulates a single-stage pump for compressible (gaseous) fluids. The unit isconsidered as a non-reversible model.

See Also

gas_pump Model: Connectivity

gas_pump Model: Configuration

gas_pump Model: Specifications

gas_pump Model: Initialization

gas_pump Model: User Procedures and Submodels Used

gas_pump Model: Results

gas_pump Model: Additional Notes

gas_pump Model: Connectivity

These are the available connections for the gas_pump model:

gas_pump Model: Configuration

These are the configuration options available for the gas_pump model:





Mode of operation Isothermal Compressor

Isentropic Compressor

Polytropic Compressor

Isentropic Vacuum Pump

Characteristic behavior of the pump





gas_pump Model: Specifications

Depending on how the gas_pump model has been configured, you need to specify one or more of these variables in the Specify table:

If using a user procedure for pump performance curve, note that these last two will require the use of pUser_g_Pump_Performance2 procedure rather than pUser_g_Pump_Performance.

gas_pump Model: Initialization No initialization method is required for the gas_pump model.

gas_pump Model: User Procedures andSubmodels Used

Depending on the model configuration, the user procedures available for the gas_pump model are:

User Defined

Pump characteristic number Integer value Performance curve number (contained within user Fortran)


Polytropic_Efficiency Polytropic efficiency of pump (polytropic pump)

Np Polytropic index

Gamma Ratio of specific heat capacities

Work Actual work requiredPower Power requirements

UsingDeRateFactor Use DeRate factor in user performance curve

DeRateFactor DeRate factor user user performance curve


pUser_g_Pump_Performance Pump performance characteristic curve

pUser_g_Pump_Performance2 Pump performance characteristic curve includingde-rate.

pUser_g_Enthalpy_Mol Molar enthalpy (user Fortran physical properties,reversible model)

pUser_g_Entropy_Mol Molar entropy (user Fortran physical properties,reversible model)

User Submodel Description

gUserPerf Pump performance characteristic curve





gas_pump Model: Results

Typical variables in the Results and Specify tables for the gas_pump model are:

gas_pump Model: Additional Notes

Note the following information when using the gas_pump model:

At low flow conditions, where the absolute value of the flowrate is less than or equal to theresidual tolerance, the information in the Report table is inaccurate.

You must connect the outlet of a vacuum pump to a gas_product unit whose pressure has beenspecified as free.

The pump performance curves come from Fortran procedures.

gas_ramp Model

The gas_ramp model drives a gas phase adsorbent bed through a series of pressure profiles. This isuseful when there is no information on valve opening coefficients, in which case the model acts as anin-situ replacement for a gas_valve.

See Also

gas_ramp Model: Connectivity

gas_ramp Model: Configuration

gas_ramp Model: Specifications

gas_ramp Model: Initialization

gas_ramp Model: User Procedures Used

Results:

gas_ramp Model: Additional Notes


Work Actual work requiredPower Power requirement

Total_Energy Total energy consumed

Cycle_Total_Energy Total energy consumed at boundary for last cycle





gas_ramp Model: Connectivity

These are the available connections for the gas_ramp model:

gas_ramp Model: Configuration

These are the configuration options available for the gas_ramp model:

gas_ramp Model: Specifications

Depending on how the gas_ramp model has been configured, you need to specify one or more of these variables in the Specify table:


Process_In g_material_port (single) gas_Material_ConnectionProcess_Out g_material_port (single) gas_Material_Connection


Unit relative location Feed

Product

Delay

Defines relative location of themodel with respect to anadsorbent bed and boundary.This automatically updates if a

gas_feed, gas_product or gas_interaction is connected.

Model type Reversible Flow Setter

Non-Reversible


Apply stop action No

Yes

For a reversible model, does the

unit also act as a non-

return/check valve


Active_Specification Specification to control the model:

0 = Fully off (zero flow)

1 = Fully open (responds as high Cv valve)

2 = Defined pressure regime (from start to end pressure, makes use of Xstart, Xend, Notional_Volume and Xfac variables)

3 = Constant flowrate (uses the value for Flowrate)

Pstart Adsorbent bed start pressure

Pend Adsorbent bed end pressure





gas_ramp Model: Initialization

No initialization method is required for the gas_ramp model.

gas_ramp Model: User Procedures Used

There are no user procedures available for the gas_ramp model.

Results:

Typical variables in the Results table for the gas_ramp model are:

gas_ramp Model: Additional Notes

Note the following information when using the gas_ramp model:

By default, the model behaves as a reversible flow setter.

Ideally, connect a pressure setter on each side.

Use the variable Active_Specification to specify the operation of the unit. All the other variables act as value "holders".

When the model is part of an interaction unit train, the approximate pressure is given by:

Notional_Volume may be quickly approximated using the Estimate button on the configureform. This calculates the interstitial volume of the gas_bed train present on the flowsheet.

Dstart Interacting bed start pressure

Dend Interacting bed end pressure

Flowrate Flowrate of material

Notional_Volume Estimated effective volume of the real bed/

XFac Effective volume correction factor


P_Change Pressure drop across the unit

Pcurrent Currently enforced pressure on adsorbent bed side





The calculated ramps are nonlinear.

When ramping down, ensure that the pressure of the connected feed or product unit is at least1 mbar below the target pressure.

When ramping up, ensure that the pressure of the connected feed or product is at least 1 mbar above the target pressure.

gas_tank_void Model

The gas_tank_void is a general purpose model for simulating adsorbent bed deadspaces (voids),tanks, pressure receivers or piping nodes.

See Also

gas_tank_void Model: Connectivity

gas_tank_void Model: Configuration

gas_tank_void Model: Specifications

gas_tank_void Model: Initialization

gas_tank_void Model: User Procedures Used

gas_tank_void Model: Results

gas_tank_void Model: Additional Notes

gas_tank_void Model: Connectivity

These are the available connections for the gas_tank_void model:

gas_tank_void Model: Configuration

These are the configuration options available for the gas_tank_void model:

Port Name Type Valid ConnectionProcess_In g_material_port (multiport) gas_Material_Connection


Option Valid Values DescriptionModel type Reversible Pressure Setter Mode of flowsheet interactivity





gas_tank_void Model: Specifications

Depending on how the gas_tank_void model has been configured, you need to specify one or moreof these variables in the Specify table:

Non-Reversible

Gas model assumption Ideal Gas

Fixed Compressibility

User Procedure Compressibility

User Submodel Compressibility

Is the gas contained an idealgas.? If not ,how is thecompressibility factor supplied?

Include compression term Yes

No

Is the heat of compression part of the energy balance?

Heat effect assumption Adiabatic

Non-Adiabatic

Is there heat exchange with theexternal environment?

Shape assumption Spherical

Cylindrical

Hemispherical

Cap

Unknown

If there is heat exchange with theenvironment, what shape is theheat transfer area?



Height Height of a cylindrical void/tank

Tan_Height Height from cap seam to apex

Diameter Diameter of cylinder/sphere/cap/hemisphere

Surface_Area Overall surface area through which heat is

exchangedZ Constant gas compressibility factor

Mass_Shell Mass of void/tank wall

Cp_Shell Heat capacity of the shell wall

HTC_Shell Heat transfer coefficient between internal gas and

wall

HTC_Env Heat transfer coefficient between wall and theenvironment

T_Shell Shell wall temperature

T_Env Environment temperature





gas_tank_void Model: Initialization

The recommended variables to initialize for the gas_tank_void model are:

To run the initialization script for the model, click the Initialize button or select Check & Initial fromthe Flowsheet menu. This calculates an approximate molar holdup for the conditions provided.

gas_tank_void Model: User Procedures Used

Depending on the model configuration, the user procedures available for the gas_tank_void model

are:

gas_tank_void Model: Results

Typical variables in the Results table for the gas_tank_void model are:

gas_tank_void Model: Additional Notes

Note the following information when using the gas_tank_void model:

By default, the model behaves as a reversible pressure setter.

Ideally, a flow setter or adsorption bed must be connected on each stream.




Internal molefractioncomposition


P Initial Internal pressure



pUser_g_Compressibility Compressibility factor (user Fortran physical properties)


Y Internal holdup composition

Mc Internal component holdup

T Internal temperatureP Internal pressure

H Internal enthalpy





The model accepts any number of inlet and outlet streams.

With the model as a node or junction, we recommend you use a minimum volume of 1E-5 m3.

With the model as a column void, we recommended you switch off the heat of compression

term as the unit is not assumed to be well mixed.

Switching off the heat of compression term makes the model perform similarly to AspenAdsorption 6.x and Aspen Adsorption 10.0.

gas_valve Model

The gas_valve model simulates a simple linear valve, an ISA valve, or a choked flow valve.

See Also

gas_valve Model: Connectivity

gas_valve Model: Configuration

gas_valve Model: Specifications

gas_valve Model: Initialization

gas_valve Model: User Procedures Used

gas_valve Model: Results

gas_valve Model: Additional Notes

gas_valve Model: Connectivity

These are the available connections for the gas_valve model:

gas_valve Model: Configuration

These are the configuration options available for the gas_valve model:





Model type Non-Reversible Mode of flowsheet interactivity





gas_valve Model: Specifications

Depending on how the gas_valve model has been configured, you need to specify one or more of these variables in the Specify table:

Reversible Flow Setter

Non-Reversible Delay

Valve characteristic Linear

ISA

ChokedPop

Characteristic behavior of thevalve


Yes

For a reversible model, does theunit also act as a non-

return/check valve?

Specifications made available Cv

Flow/Cv

Flow specification methods for linear valve.


Active_Specification For linear valves, depending on your choice for Specifications Made Available, the following

specifications can be used:

0 = Valve fully off

1 = Valve fully on (acts as a valve with high Cv)

2 = Make use of the value specified for Cv(constant Cv)

3 = Make use of the value specified for Flowrate(constant flowrate)

The specification can be changed during runtime

Cv Linear valve coefficient (only used whenActive_Specification = 2)

Flowrate Constant forced flowrate (only used whenActive_Specification = 3)

Popen Pressure at which a Pop valve automaticallyopens

Pclose Pressure at which a Pop valve automaticallycloses

Cv_ISA Valve coefficient for an ISA or Choked valve

Xt Pressure drop ratio for an ISA or Choked valve





gas_valve Model: Initialization

No initialization method is required for the gas_valve model.

gas_valve Model: User Procedures Used

Depending on the model configuration, the user procedures available for the gas_valve model are:

Note: These are all user FORTRAN physical properties procedures used in ISA/Chokedconfiguration and will not be called when using rigorous properties.

gas_valve Model: Results

Typical variables in the Results table for the gas_valve model are:

gas_valve Model: Additional Notes Note the following information when using the gas_valve model:

By default, the model behaves as a linear reversible flow setter.

Ideally, a pressure setter must be connected on each side of the valve.

The control action can be any real number from 0 to 1.

This applies to models configured as a linear valve with forced flow and stop action: if the

pressure equalizes across the valve, the flow of material stops.

If a gas_interaction model is connected to the outlet, the non-reversible delay valveconfiguration is detected automatically on opening the configure form.


pUser_g_Avg_Mole_Weight Average molecular weight of gas

pUser_g_Heat_Capacity_Cv Gas heat capacity at constant volume

pUser_g_Heat_Capacity_Mol Gas heat capacity at constant pressure

pUser_g_Compressibility Compressibility factor

Variable DescriptionP_Change Pressure change across the valve

Control_Action External controller action applied

delta_p Ideal pressure drop in Choked valve

chkfac If greater than 1, choked flow has occurred

P_Choke Choking pressure





The Pop feature allows the valve to automatically open and close, based on an opening and

closing pressure. Initially, the valve is assumed closed. The valve characteristic is linear anduses the same specifications.

The ISA correlation used is as follows:

where:M = Mass flowrate (kg/h)

N6 = Constant, 27.3Fp = Piping geometry factor (assumed = 1)Cv = Valve flow coefficientY = Expansion factor x = Ratio of pressure drop to absolute upstream pressurext = Pressure drop ratio factor

p1 = Absolute upstream pressure (bar)

1 = Specific weight

For choked flow, the pressure drop ratio factor, , is given by:

and the pressure drop at which choked flow occurs by:

gCSS Models

The table lists the gCSS (CSS gas phase) models available in Aspen Adsorption. You connect thesemodels using the gCSS_Material Connection stream:

Model Description

gCSS_Adsorber Adsorbent bed layers.gCSS_HeatX General instantaneous heat exchanger (optional

liquid condensate stream).

gCSS_Interaction Pseudo-bed for single bed approach.

gCSS_Pump Compressor or vacuum pump.

gCSS_SixPortInjectorg 6-port injection valve model with internal hold up by either a tube or a void.

gCSS_TankVoid General purpose tank/void model to account for spaces and holdup.

gCSS_Valve Valve model.





gCSS_Adsorber Model

The gCSS_Adsorber model simulates an adsorption bed unit in a gas flowsheet. It acts like acontainer model for the bed layers and their interconnections.

See Also

gCSS_Adsorber Model: Connectivity

gCSS_Adsorber Model: Configuration/Specification

gCSS_Adsorber Model: Initialization

gCSS_Adsorber Model: User Procedures/User Submodels

gCSS_Adsorber Model: Results

gCSS_Adsorber Model: Additional Notes

gCSS_Adsorber Model: Connectivity

These are the available connections for the gCSS_Adsorber model:

gCSS_Adsorber Model:

Configuration/Specification

These are the configuration tables available for the gCSS_Adsorber model (alphabetical order):

Port name Type Valid connection

Process_In gCSS_port (single) gCSS_Material_ConnectionProcess_Out gCSS_port (single) gCSS_Material_Connection

Tables Variables/Parameters to be supplied by users

Config_AdsorbentProperty

Physical properties and packing characteristics of adsorbent layers with the bed.

User description on each adsorbent layer (AdsorbentDescription)

Particle radius (rp)

Bed voidage (ei)

Intraparticle voidage (ep)

Total voidage (et)

Particle density (rhop)





Bed density (rhob)

Config_EnergyBalance:

Energy balance assumptions around the system

and physical/chemical properties relate to systemtemperatures as well as the energy conservation

principle.

Adiabatic/non-adiabatic simulationassumption (NonAdiabatic)

Column wall balance assumption for non-adiabatic simulation

(RigorousWallBalance)

Column wall thickness (wt)

Axial conduction assumption in gastemperature (FluidPhaseConduction)

Gas conductivity supplies either by user or properties packages (UserDefined_Kg)

Axial conduction assumption in solid

temperature (SolidPhaseConduction)

Soild conductivity (Ks)

Contribution by isosteric heats of adsorption (IncHeatAdsorption)

Contribution by condensation/latentheats on adsorbed phase(IncHeatAdsorbedPhase)

Heat capacity of the adsorbed phasesupplies either by user of properties

package (UserDefined_Cpa)

Heat of adsorption assumption(dHForm)

Constant heat of adsorption (dH)

Gas-solid heat transfer assumption(HsForm)

Gas-solid HTC (Hs)

Gas-wall heat transfer assumption(HwForm)

Gas-wall HTC (Hw)

Wall-environment HTC (Hamb)

Ambient/environment temperature (Ta)

Solid heat capacity (Cps)





Wall heat capacity (Cpw)

Wall density (rhow)

Config_Equilibrium:

Equilibrium theory assumptions and the

properties.

Equilibrium model assumption

(EquilibriumModel)

Isotherm parameter dependency

(IsothermDependency)

Non-ideal gas phase assumption for IAST calculation (IAST_ (*).NonIdealGasPhase_IAST)

Pure isotherm selection for IAST

calculation (PureIsothermType)

Non-ideal gas phase assumption for GEM calculation (GEM_ (*).NonIdealGasPhase_IAST)

Pure isotherm selection for GEMcalculation (PureIsothermType_GEM)

Non-ideal gas phase assumption for GEM calculation with diffusion

pore/combined kinetic model(ParticleMB_.GEM_

(*).NonIdealGasPhase_IAST)

Pure isotherm selection for IASTcalculation with diffusion pore/combined

kinetic model (ParticelMB_.IAST_ (*).PureIsothermType_Pore)

Non-ideal gas phase assumption for IAST calculation with diffusion

pore/combined kinetic model(ParticelMB_.IAST_

(*).NonIdealGasPhase_IAST_Pore)

Isotherm parameters (IP(*))

GEM reference temperature T1 (T1)

GEM Isotherm parameters at T1

GEM reference temperature T2 (T2)

GEM Isotherm parameters at T2

Config_FlowDirection:

Forced directional flow assumption – optional inCSS mode only.

Forced flow direction of each operationstep in CSS mode (Direction_spec)





Config_Geometry:

Adsorber and the layer geometry and sorptionfrontal assumption.

Adsorber geometry (Geometry)

Sorption frontal shape (Frontal shape)

The number of adsorbent layers withinthe adsorber (NumberLayers)

Packing height of adsorbent layer (hb)

Packing length for horizontal layer withrectangular frontal shape (L_horizontal)

Internal diameter of circular frontalshape bed, or the other side length for rectangular frontal shape bed (db)

Variable db for variable frontal area bed

(db_Characteristic)Config_Kinetics:

Sorption kinetic model assumptions and thekinetic parameters.

Sorption kinetic model assumption(KineticModel)

Mass transfer film assumption inlinear/quadratic driving force model(MTFilm)

Mass transfer coefficient assumption(MTCForm)

External film mass transfer coefficientmodel assumption in diffusion kineticmodel (ParticleMB_ (*).ExternalMTCForm)

Lumped MTC in solid filmlinear/quadratic driving force model(ksLDF)

Lumped MTC in fluid filmlinear/quadratic driving force model

(kfLDF)

Pressure dependent lumped MTC insolid film linear/quadratic driving forcemodel (ksLDFp)

Pressure dependent lumped MTC influid film linear/quadratic driving forcemodel (kfLDFp)

Constant for Arrhenius-type MTC in

linear/quadratic driving force model (k0)

Constant for pressure dependentArrhenius-type MTC in linear/quadratic





driving force model (k0)

Activation energy for Arrhenius-typeMTC in linear/quadratic driving forcemodel (Eact)

Effective diffusivity for a lumped MTCin linear/quadratic driving force model(De)

Surface diffusivity assumption for diffusion surface/combined kinetic model(DsForm)

Constant surface diffusivity in diffusionsurface/combined kinetic model(Ds_Const)

Constant in Eyring surface diffusivitymodel (Ds0)

Proportional constant for Eyringactivation energy (EyringPropConstant)

Pore diffusivity assumption for diffusion

pore/combined kinetic model (DpForm)

Constant pore diffusivity in diffusion pore/combined kinetic model (Dp_Const)

Average pore radius (r_Pore)

Tortuosity factor (TortuosityFactor)

Config_MaterialMomentum:

Assumptions in material balance and inmomentum balance

Momentum balance assumption(MomentumBalance)

Axial dispersion assumption(ConvectiveOnly)

Axial dispersion coefficient modelassumption (DLForm)

Constant axial dispersion coefficient(DL)

Config_Numerics:

Numerical methods and the parameters

Bed axial discretisation method(PDEMethod)

Bed axial discretisation node numbers(xNodes)

Boundary condition approximation atmultiple layer interface(LayerInterfaceApprox)





gCSS_Adsorber Model: Initialization

Since gCSS_Adsorber model operates in either dynamic or CSS mode, there are two initializationmethods are presented for each simulation mode. Whatever the simulation mode, the initialization of

gCSS_Adsorber model will be finalized by executing one of the initialization scripts:Initialize_Unit_All, Initialize_Unit_Spec, Initialize_Unit_Value. Detailed procedures of theinitialization for each simulation mode are given in Adsorption Reference Guide.

gCSS_Adsorber Model: User Procedures/User

SubmodelsThere are no user procedures or user submodels available for the gCSS_Adsorber model. Any user

customization code will be implemented through the flowsheet constraint.

gCSS_Adsorber Model: Results

There is a dynamic simulation result axial plot available. The axial plots shows the distributedvariables of gas temperature (Tg), pressure (P), and superficial gas velocity (Vg).

gCSS_Adsorber Model: Additional Notes

Note the following information when using the gCSS_Adsorber model:

You can give a label or ID number for each adsorbent layer in the bed (use the string

parameter AdsorbentDescription within Config_AdsorbentProperty table).

The gCSS_Adsorber model does not include any inlet or outlet dead space. Use agCSS_TankVoid model at each end to simulate dead space.

The order of boundary approximation at

multiple layer interface(LInterfaceApproxOrder)

Layer entrance/exit boundary condition

assumption (Boundary_Condition)

Particle radial discretisation method(rPDEMethod)

Particle radial discretisation nodenumbers (rNodes)





The gCSS_Adsorber supports both dynamic simulation and cyclic steady-state simulation, and

distributed variables are distributed not only in spatial domain but also in temporal domain.When a problem is defined in dynamic simulation mode, temporal domain is set with a nulldimension: for example, Tg(0).value(1~n). If problem is defined in cyclic steady-state (CSS)mode, then temporal domain will be active ranging from 0(zero) to TotalTimeNodes that is

pre-declared in the global table.

gCSS_HeatX Model

The gCSS_HeatX model modifies the temperature of an inlet stream. By default, it operates at aconstant outlet temperature. You can change the model operation to either constant duty or constant

temperature rise/drop.

See Also

gCSS_HeatX Model: Connectivity

gCSS_HeatX Model: Configuration/Specification

gCSS_HeatX Model: Initialization

gCSS_HeatX Model: User Procedures/Submodels Used

gCSS_HeatX Model: Results

gCSS_HeatX Model: Additional Notes

gCSS_HeatX Model: Connectivity

These are the available connections for the gCSS_HeatX model:

gCSS_HeatX Model:


Depending on how the gCSS_HeatX model has been configured, you need to specify one or more of

these variables in the Configuration table:


Process_In gCSS_port (single) gCSS_Material_Connection

Process_Out gCSS_port (single) gCSS_Material_ConnectionLiquid_Out gCSS_port (single, optional) gCSS_Material_Connection






gCSS_HeatX Model: Initialization

No initialization method is required for the gCSS_HeatX model.

gCSS_HeatX Model: User

Procedures/Submodels Used

There are no user procedures or user submodels available for the gCSS_HeatX model. Any user customization code will be implemented through the flowsheet constraint.

gCSS_HeatX Model: ResultsUse All Variable table to see results. Otherwise use outlet steam report/result tables.

gCSS_HeatX Model: Additional Notes

No additional notes.

gCSS_Interaction Model

Use the gCSS_Interaction model as part of the single bed modeling approach, to record the profile of

material received, then later replay this profile to simulate returned material. The following arerecorded over time:

Molar flowrate

Mole fraction composition

Temperature

Use_spec(*) Heat exchanger assumption.

Tout_spec(*) Outlet temperature.

Tchange_spec(*) Temperature rise/drop of process stream.

Q_spec(*) Heat exchanger duty.

U(*) Overall heat transfer coefficient.

Heat_Exchange_Area Heat exchange area.

P_Drop Constant average pressure drop.





Upstream (bed) pressure

Specific enthalpy

By acting as a pseudo-adsorbent bed, the model can behave as a bed at either constant or varying

pressure. Use the Cycle Organizer to define the steps between which an interaction occurs.

You can define any type of bed interaction with the model:

Top-to-top

Top-to-bottom

Bottom-to-bottom

Bottom-to-top

These are defined by the connectivity, that is where material is accepted from and returned to.Interactions cannot be redefined during a run as connectivity is structural, so if you want more thanone type of interaction, use additional interaction models.

In the first cycle, during cyclic operation, the model uses an approximation based on an assumedeffective volume, to simulate the pressure of the interacting bed. For subsequent cycles, the recorded

pressure profile of the rigorously modeled bed provides an accurate response for the pseudo bed.

See Also

gCSS_Interaction Model: Connectivity

gCSS_Interaction Model: Configuration/Specification

gCSS_Interaction Model: Initialization

gCSS_Interaction Model: User Procedures/User Submodels Used

gCSS_Interaction Model: Results

gCSS_Interaction Model: Additional Notes

gCSS_Interaction Model: Connectivity

These are the available connections for the gCSS_Interaction model:



Process_Out gCSS_port (single) gCSS_Material_Connection





gCSS_Interaction Model:Configuration/Specification

These are the configuration options available for the gCSS_Interaction model:

Depending on how the gCSS_Interaction model has been configured, you need to specify one or more of these variables in the Specify table:

Note: All these variables are used in the first cycle of a dynamic simulation. In CSS simulation, the

first cycle assumption is not necessary and the gCSS_Interaction model will not use a delay modelfor replay profiles. Therefore a user only needs to define the step interaction, in CSS simulationmode.

gCSS_Interaction Model: Initialization No initialization method is required for the gCSS_Intaraction model.

gCSS_Interaction Model: UserProcedures/User Submodels Used

There are no user procedures or user submodels available for the gCSS_Interaction model.

Option Valid values Description Comment

Delay_Behaviour v10xv6x

Assumption used for subsequent cycles.

Use real profile or continue with estimated

profile.

FIFO_Interaction TrueFalse

Type of profile buffer used.

Standard first-in-first-out, or inverted first-in-last-out.


Notional_Volume Estimated effective volume of the real bed/s.

P_Stage_Start_spec Start pressure of the interaction unit.

XFac_spec Effective volume correction factor.

F_Initial_Reverse Average flowrate of returned material during areverse interaction.

Y_Initial_Reverse Average composition of returned material duringa reverse interaction.

T_Initial_Reverse Average temperature of material during a reverseinteraction.

P_Initial_Reverse Average pressure of returned material during a

reverse interaction.





gCSS_Interaction Model: Results

Use All Variable table to see results. Otherwise use outlet steam report/result tables.

gCSS_Interaction Model: Additional Notes

Note the following information when using the gCSS_Interaction model:

The model assumes that standard unit operation is a first-in-first-out (FIFO) buffer profile. For specialist applications, you can invert this profile, but this is a structural parameter, so your new profile applies to all interactions in a unit.

If the buffer profile is assumed first-in-last-out, the delay behavior uses estimated pressure

profiles for all cycles.

The communication interval affects model accuracy. If interactions are present, try to have atleast three communication points within the shortest interacting steps.

The model uses a Delay function. Exiting Aspen Adsorption, loading a new problem or reopening the old problem, all clear the delay buffer so historical information is lost.

By default, the approximation or initial reverse values are only used in the first cycle. You canapply these to all cycles by changing the delay behavior to v6x.


Use the Cycle Organizer to define the interaction and profile times.

For the unit inlet stream, use a gCSS_Valve or gCSS_HeatX model; for the outlet, connect anymodel except a gCSS_Valve. (The Check & Initial option on the Flowsheet menu detectserrors here and corrects accordingly.)

The model approximates the pressure in the interaction unit using:

The variables Notional_Volume, P_Stage_Start_spec, XFac_spec, F_Initial_Reverse,Y_Initial_Reverse, T_Initial_Reverse and P_Initial_Reverse are used only in the first dynamiccycle. They are ignored in subsequent cycles.

Within the Cycle Organizer, reset P_Stage_Start_spec to the required value for each step.Pressure changes then start from this value.

XFac_spec may need modifying from step to step. To do this, use the Cycle Organizer.

To simulate a constant pressure interaction, set XFac_spec to a high value, such as 100 or more. This increases the volume to such an extent that it acts like a void of near infinitecapacity.





gCSS_Pump Model

The gCSS_Pump model simulates a single-stage pump for compressible (gaseous) fluids. The unit isconsidered as a non-reversible model.

See Also

gCSS_Pump Model: Connectivity

gas_pump Model: Configuration/Specification

gCSS_Pump Model: Initialization

gCSS_Pump Model: User Procedures/User Submodels Used

gCSS_Pump Model: Results

gCSS_Pump Model: Additional Notes

gCSS_Pump Model: Connectivity

These are the available connections for the gCSS_Pump model:

gCSS_pump Model:Configuration/Specification

These are the configuration options available for the gas_pump model:




Option Valid values Description

Pump_Type Isothermal Compressor

Isentropic Compressor

Polytropic Compressor

Isentropic Vacuum Pump

User Defined

Characteristic behavior of the pump.

Performacne_Type Constant Volume Performance curve method





Depending on how the gCSS_Pump model has been configured, you need to specify one or more of these variables in the Specify table:

Note: For a variable volumetric flowrate, a user needs to change the spec of Vol_Flow_spec fromFixed to Free, and then provide a flowrate expression through the flowsheet constraint.

gCSS_Pump Model: Initialization

No initialization method is required for the gCSS_Pump model.

gCSS_Pump Model: User Procedures/User

Submodels UsedThere are no user procedures or user submodels available for the gCSS_Pump model. Any user customization code will be implemented through the flowsheet constraint.

gCSS_Pump Model: Results

Typical variables in the Configuration table for the gCSS_Pump model are:

gCSS_Pump Model: Additional Notes

No additional notes.

User Supplies


Efficiency Pump efficiency.

Vinlet_spec Constant inlet volumetric flowrate.

Vol_Flow_spec User supplied volumetric flowrate.

Work Actual work required.

Power Power requirement.


Work Actual work required.

Power Power requirement.





gCSS_SixPortInjector Model

The gCSS_SixPortInjector model simulates a six-port injection valve, which is used for making a pulse input in chromatography system. As a commercial six-port inject valve is, thegCSS_SixPortInjector model have an internal void/tube to hold up materials to be injected. Theillustrations (click here to display) present how gCSS_SixPortInjector model operates betweenLoading and Injection modes.

See Also

gCSS_SixPortInjector Model: Connectivity

gCSS_SixPortInjector Model: Configuration/Specification

gCSS_SixPortInjector Model: Initialization

gCSS_SixPortInjector Model: User Procedures Used

gCSS_SixPortInjector Model: Results

gCSS_SixPortInjector Model: Additional Notes

gCSS_SixPortInjector Model: Connectivity

This is the available connection for the gCSS_SixPortInjector model:

gCSS_SixPortInjector Model:


These are two configuration tables available for the gCSS_SixPortInjector model: Valve and SampleLoop

Configuration_Valve table (valve operation)


Port1 gCSS_port (single) gCSS_Material_Connection







Automatic_Actuation True Does the valve have anautomatic actuator operative





False with respect to time?

If True, operation doesn’t needan external time control such asCycle Organizer. If False, it does

need an external control.

The specification cannot bechanged during runtime.

SetTime_Loading Real or Integer Time required for charge(loading).

SetTime_Injection Real or Integer Time required for discharge(injection).

CycleTime Time SetTime_Loading +SetTime_Injection

CurrentTime Time Current simulation time

Position_Dynamic 0 or 1 0 = Loading (charge)

1 = Injection (discharge)

Specification: Fixed

(Automatic_Actuation = False)and Free (Automatic_Actuation= True)

CheckValve_Port1_spec 0 or 1 Configuration of the linear valveat Port 1

0 = bidirectional flow available

1 = check valve operation

CheckValve_Port3_spec 0 or 1 Configuration of the linear valve

at Port 3

0 = bidirectional flow available

1 = check valve operation

Use_Port1_spec 0, 1, 2, 3, 4 Configuration of the linear valveat Port 1

The following specifications can be used:

0 = Valve fully off.

1 = Valve fully on (acts as avalve with highest Cv, default setvalue Cv_max = 100).

2 = Make use of the valuespecified for Cv_spec (constant

Cv).

3 = Make use of the value





Note: Automatic_Actuation is not available in the CSS simulation mode. In addition, the internal

specified for F_spec (constant

molar flowrate).

4 = Make use of the valuespecified for V_spec (constant

volumetric flowrate).

The specification can be changedduring runtime.

Use_Port3_spec 0, 1, 2, 3, 4 Configuration of the linear valveat Port 3

The following specifications can be used:


1 = Valve fully on (acts as avalve with highest Cv, default setvalue Cv_max = 100).

2 = Make use of the valuespecified for Cv_spec (constantCv).

3 = Make use of the valuespecified for F_spec (constantmolar flowrate).

4 = Make use of the valuespecified for V_spec (constantvolumetric flowrate).

The specification can be changedduring runtime.

Cv_Port1_spec Linear valve coefficient (onlyused when Use_Port1_spec = 2).

Cv_Port3_spec Linear valve coefficient (onlyused when Use_Port3_spec = 2).

F_Port1_spec Constant forced molar flowrate(only used when Use_Port1_spec= 3).

F_Port3_spec Constant forced molar flowrate(only used when Use_Port3_spec= 3).

V_Port1_spec Constant forced volumetricflowrate (only used whenUse_Port1_spec = 4).

V_Port3_spec Constant forced volumetricflowrate (only used when

Use_Port3_spec = 4).





linear valve at port 5 is always in fully open position to allow bidirectional flow.

Configuration_SampleLoop table (internal sampling loop)

gCSS_SixPortInjector Model: InitializationThere is Initailization_DYN table for the initialization of the internal sampling loop of thegCSS_SixPortInjector model. The recommended variables to initialize the gCSS_SixPortInjector model block for a dynamic simulation are:

To finalize the initialization of the model, explore the model block and double-click the

Initialize_All script.

gCSS_SixPortInjector Model: User Procedures

UsedThere are no user procedures or user submodels available for the gCSS_SixPortInjector model. Any


SampleLoopType Void assumed

Tube assumed

Sampling loop type assumption

WantToFixTemp True

False

Is the sampling void in specifically isothermaloperation? If it is True, then theambient/environment temperature will be used

for the isothermal sampling void temperature.

NonAdiabaticTankVoidTrue

False

Is there heat exchange with the externalenvironment?

Ta Ambient/Environment temperature.

Volume Total internal volume of the sampling void.

mass Mass of sampling void.Cpw Heat capacity of the shell wall of the sampling

void.

Hamb Wall-environment heat transfer coefficient.

Hw Gas-Wall heat transfer coefficient.

A_inner Inner surface area of sampling void.

A_outer Outer surface area of sampling void.


SampleLoop_.Void_(1).Y Initial (ncomps-1)


Internal molefractioncomposition.

SampleLoop_.Void_(1).P Initial Internal pressure.SampleLoop_.Void_(1).T Initial Internal temperature.





user customization code will be implemented through the flowsheet constraint.

gCSS_SixPortInjector Model: Results

There is Result_StatusPlot_DYN plot available for the dynamic simulation results with respect totime. Typical variables in the result plot are:

A user can add other variables, such as C (component concentration), P (pressure) or H (enthalpy)

into the result plots.

gCSS_SixPortInjector Model: Additional Notes

Note the following information when using the gCSS_SixPortInjector model:

This model is especially designed for a dynamic simulation purpose such as gas phasechromatographic separations.

If there is a need to connect gCSS_Valve model with the gCSS_SixPortInjector model(possible locations are Port 1, Port 3, Port 4 and Port 6), you must have gCSS_TankVoidmodel between gCSS_Valve and any Port of the gCSS_SixPortInjector.

Try to have at least three communication points within the time settings for loading/injection(SetTime_Loading, SetTime_Injection).

gCSS_TankVoid ModelThe gCSS_TankVoid is a general purpose model for simulating adsorbent bed dead-spaces (voids),tanks, pressure receivers or piping nodes.

See Also

gCSS_TankVoid Model: Connectivity

gCSS_TankVoid Model: Configuration/Specification

gCSS_TankVoid Model: Initialization

gCSS_TankVoid Model: User Procedures/User Submodels Used


Sample F Flowrate at Port 1

Carrier F Flowrate at Port 3

Column F Flowrate at Port 4

Vent F Flowrate at Port 6





gCSS_TankVoid Model: Results

gCSS_TankVoid Model: Additional Notes

gCSS_TankVoid Model: ConnectivityThese are the available connections for the gCSS_TankVoid model:

gCSS_TankVoid Model:Configuration/Specification

These are the configuration options available for the gCSS_TankVoid model:

Depending on how the gCSS_TankVoid model has been configured, you need to specify one or more of these variables in the Configuration table:

gCSS_TankVoid Model: Initialization


Process_In gCSS_port (multiport) gCSS_Material_Connection

Process_Out gCSS_port (multiport) gCSS_Material_Connection


WantToFixTemp True

False

Is the tankvoid in specificallyisothermal operation? If it isTrue, then the

ambient/environmenttemperature will be used for theisothermal tankvoid temperature.

NonAdiabaticTankVoid True

False

Is there heat exchange with the

external environment?


Ta Ambient/Environment temperature.

Volume Total internal volume of the tank/void.

mass Mass of void/tank wall.

Cpw Heat capacity of the shell wall.

Hamb Wall-environment heat transfer coefficient.

Hw Gas-Wall heat transfer coefficient.

A_inner Inner surface area of tank/void.

A_outer Outer surface area of tank/void.





Since gCSS_TankVoid model operates in either dynamic or CSS mode, there are two initialization

methods are presented for each simulation mode. And at the end, whatever the simulation mode, theinitialization of gCSS_TankVoid model will be finalized by executing one of the initializationscripts: Initialize_All.

The recommended variables to initialize for a dynamic simulation are:

And the recommend variables for initial guess of CSS simulation are:

To finalize the initialization of the model, explore the model block and double-click theInitialize_All script.

gCSS_TankVoid Model: User Procedures/UserSubmodels Used

There are no user procedures or user submodels available for the gCSS_TankVoid model. Any user customization code will be implemented through the flowsheet constraint.

gCSS_TankVoid Model: Results

There are two result plots are available: Result_Plot_DYN (time plot) and Result_Plot_CSSProfile(profile plot). Typical variables in the result plots are:

A user can add other variables, such as C (component concentration) or H (enthalpy) into the result plots.




Internal molefractioncomposition.

P Initial Internal pressure.

T Initial Internal temperature.

Tw Initial Shell/wall temperature.

Variable DescriptionInitialCSS_P_spec Initial guess of pressure for each step

InitialCSS_Y_spec Initial guess of gas composition for each step

InitialCSS_T_spec Initial guess of temperature for each step

InitialCSS_C_spec Initial guess of component concentration for eachstep


T Internal temperature.

P Internal pressure.





gCSS_TankVoid Model: Additional Notes

Note the following information when using the gCSS_TankVoid model:

The model accepts any number of inlet and outlet streams.

With the model as a node or junction, we recommend you use a minimum volume of 1E-5 m3.

gCSS_Valve Model

The gCSS_Valve model simulates a simple linear valve.

See Also

gCSS_Valve Model: Connectivity

gCSS_Valve Model: Configuration/Specification

gCSS_Valve Model: Initialization

gCSS_Valve Model: User Procedures/Submodels Used

gCSS_Valve Model: Results

gCSS_Valve Model: Additional Notes

gCSS_Valve Model: Connectivity

These are the available connections for the gCSS_Valve model:

gCSS_Valve Model:Configuration/Specification

These are the configuration options available for the gCSS_Valve model:

Port name Type Valid connectionProcess_In gCSS_port (single) gCSS_Material_Connection







In addition, you need to specify one or more of these variables in the Configuration table:

Note: When you use a valve for constant flowrate (Use_spec = 3 or 4), you must make sure theupstream pressure is higher than the downstream pressure. Without having a least difference in the

pressure, no flows will be made for a valve for constant flowrate. For example, the flow of materialstops if the upstream pressure is equal or less than the downstream pressure.

gCSS_Valve Model: Initialization No initialization method is required for the gCSS_Valve model.

gCSS_Valve Model: UserProcedures/Submodels Used

There are no user procedures or user submodels available for the gCSS_Valve model.

CheckValve True

False

Does the valve act as a

check/non-return valve?

Variable DescriptionUse_spec The following specifications can be used:


1 = Valve fully on (acts as a valve with highestCv, default set value Cv_max = 100).

2 = Make use of the value specified for Cv_spec(constant Cv).

3 = Make use of the value specified for F_spec(constant molar flowrate).

4 = Make use of the value specified for V_spec(constant volumetric flowrate).

The specification can be changed during runtime.

Cv_spec Linear valve coefficient (only used when

Use_spec = 2).

F_spec Constant forced molar flowrate (only used whenUse_spec = 3).

V_spec Constant forced volumetric flowrate (only usedwhen Use_spec = 4).





gCSS_Valve Model: Results

Use All Variable table to see results. Otherwise use outlet steam report/result tables.

gCSS_Valve Model: Additional Notes

Note the following information when using the gCSS_Valve model:

Negative sign of flowrate (F_spec, V_spec) can be applied for a reversal of forced flowrate.

Ion-Exchange ModelsThe table lists the ion-exchange models available in Aspen Adsorption. You connect these models

using the ionx_Material Connection stream.

ionx_bed ModelThe ionx_bed model simulates an ion-exchange unit in an ion-exchange flowsheet. It acts as a

container model for the ion-exchange resin layers and their interconnections.

See Also

ionx_bed Model: Connectivity

ionx_bed Model: Configuration

ionx_bed Model: Specifications

ionx_bed Model: Initialization

Model Description

ionx_bed Resin bed layers

ionx_feed Feed/inlet boundary terminator

ionx_feed_distrib Feed distributor

ionx_interaction Pseudo bed for single bed approach

ionx_mix_multi_nr Multi inlet non-reversible mixer

ionx_mix_nr2 2 inlet stream non-reversible selector ionx_mix_nr3 3 inlet stream non-reversible selector

ionx_prod_distrib Product distributor

ionx_product Product/outlet terminator boundary

ionx_split_nr2 2 outlet non-reversible selector

ionx_valve_nr Flow setting device





ionx_bed Model: User Procedures Used

ionx_bed Model: Results

ionx_bed Model: Additional Notes

ionx_bed Model: Connectivity

These are the available connections for the ionx_bed model:

ionx_bed Model: Configuration

This is the configuration option available for the ionx_bed model:

ionx_bed Model: Specifications

No specifications are required for the bed, but each resin layer has its own specifications.

ionx_bed Model: Initialization

No initialization method is required for the ionx_bed model, but each contained layer needsinitializing.

ionx_bed Model: User Procedures Used

There are no user procedures available for the ionx_bed model.


Process_In i_material_port (single) ionx_Material_Connection

Process_Out i_material_port (single) ionx_Material_Connection


Number of layers Integer (1 or higher) Number of independent resinlayers with the bed





ionx_bed Model: Results

There are no recommended results for the ionx_bed model.

ionx_bed Model: Additional Notes

Note the following information when using the ionx_bed model:


The model does not include any inlet or outlet dead space.

The model behavior is reversible, so you must connect distributors or feed and product units at

each end.

ionx_feed Model

The ionx_feed model terminates an inlet/feed flowsheet boundary. Use it to specify the ionconcentration and bulk molar density of the stream. If configured as a reversible model, the modelacts as a product sink should the flow reverse.

See Also

ionx_feed Model: Connectivity

ionx_feed Model: Configuration

ionx_feed Model: Specifications

ionx_feed Model: Initialization

ionx_feed Model: User Procedures Used

ionx_feed Model: Results

ionx_feed Model: Additional Notes

ionx_feed Model: Connectivity

These are the available connections for the ionx_feed model:







ionx_feed Model: Configuration

These are the configuration options available for the ionx_feed model:

ionx_feed Model: Specifications

Depending on how the ionx_feed model has been configured, you need to specify one or more of these variables in the Specify table:

ionx_feed Model: Initialization

No initialization method is required for the ionx_feed model.

ionx_feed Model: User Procedures Used

There are no user procedures available for the ionx_feed model.

ionx_feed Model: ResultsTypical variables in the Results and Reports tables for the ionx_feed model are:



Model type Reversible

Non-Reversible



False


Variable Description Reversible/Non-reversibleModel

C_Out Ion concentration Non-reversible model

Rhol_Out Bulk molar density Non-reversible model

C_Fwd Ion concentration Reversible model

Rhol_Fwd Bulk molar density Reversible model





ionx_feed Model: Additional Notes

Note the following information when using the ionx_feed model:

For forced feed (fixed material flowrate, no valve fitted to the outlet), it is valid to specify

F_Out or F as Fixed.

ionx_feed_distrib Model

Use the ionx_feed_distrib model as a four-way valve within an ion-exchange flowsheet. The modelis reversible and contains two inlet and two outlet ports.

See Also

ionx_feed_distrib Model: Connectivity

ionx_feed_distrib Model: Configuration

ionx_feed_distrib Model: Specifications

ionx_feed_distrib Model: Initialization

ionx_feed_distrib Model: User Procedures Used

ionx_feed_distrib Model: Results

ionx_feed_distrib Model: Additional Notes

ionx_feed_distrib Model: Connectivity

These are the available connections for the ionx_feed_distrib model:

Variable Description Reversible/Non-Reversible

Model

F_Out Volumetric flowrate Non-reversible model

F Volumetric flowrate Reversible model

C_Rev Stream composition in reversedirection

Reversible model

Rhol_Rev Stream bulk molar density inreverse direction

Reversible model


Process_In1 i_material_port (single) ionx_Material_Connection






ionx_feed_distrib Model: Configuration No configuration options are available for the ionx_feed model.

ionx_feed_distrib Model: Specifications

Depending on how the ionx_feed_distrib model has been configured, you need to specify one or more of these variables in the Specify table:

ionx_feed_distrib Model: Initialization No initialization method is required for the ionx_feed_distrib model.

ionx_feed_distrib Model: User ProceduresUsed

There are no user procedures available for the ionx_feed model.

Process_Out1 i_material_port (single) ionx_Material_Connection



Mode Distribution setting:

1 = Process_In1 and Process_Out1 connected andflowrate set to Flow. Zero flow for other streams.

2 = Process_Out1 and Process_Out2 connected

and flowrate set to Flow. Process_In1 set to zeroflow.

3 = Process_In2 and Process_Out1 connected.Process_In1 and Process_Out2 set to zero flow.

4 = Process_In1 set to Flow, Process_Out1 equalto the sum of Process_In1 and Process_In2.Process_Out2 set to zero flow.

Flow Nominal volumetric flowrate





ionx_feed_distrib Model: Results

Typical variables in the Results table for the ionx_feed model are:

ionx_feed_distrib Model: Additional Notes

Note the following information when using the ionx_feed model:

The flow in stream Process_Out1 may reverse.

Typically, stream Process_In1 connects to a feed unit and Process_Out1 connects to a bed.

ionx_interaction Model

Use the ionx_interaction model as part of the single bed modeling approach, to record the profile of

material received, then later replay this profile to simulate returned material. The followinginformation is recorded over time:

Volumetric flowrate

Ion concentration

Bulk molar density

Any type of bed interaction can be defined:

Top-to-top

Top-to-bottom

Bottom-to-bottom

Bottom-to-top

You specify the type of interaction through the connectivity (where material is accepted from, andreturned to). During a run, interaction cannot be redefined as connectivity is structural, so if youwant more than one type of interaction, use additional interaction models.

By acting as a pseudo adsorbent bed, it is possible for the model to behave as a bed at either constantor varying pressure. Use the Cycle Organizer to define the steps between interactions.


Process_In1.F Volumetric flowrate of inlet stream 1Process_In2.F Volumetric flowrate of inlet stream 2

Process_Out1.F Volumetric flowrate of outlet stream 1






See Also

ionx_interaction Model: Connectivity

ionx_interaction Model: Configuration

ionx_interaction Model: Specifications

ionx_interaction Model: Initialization

ionx_interaction Model: User Procedures Used

ionx_interaction Model: Results

ionx_interaction Model: Additional Notes

ionx_interaction Model: Connectivity

These are the available connections for the ionx_interaction model:

ionx_interaction Model: Configuration

No configuration options are available for the ionx_interaction model.

ionx_interaction Model: Specifications

Depending on how the ionx_interaction model has been configured, you need to specify one or moreof these variables in the Specify table:

Note: All these variables are used in the first cycle.





F_Initial Average flowrate of returned material during areverse interaction

C_Initial Average concentration of returned material during

a reverse interaction

Rhol_Initial Average bulk density of material during a reverseinteraction





ionx_interaction Model: Initialization

No initialization method is required for the ionx_interaction model.

ionx_interaction Model: User Procedures Used

There are no user procedures available for the ionx_interaction model.

ionx_interaction Model: Results

There are no recommended results for the ionx_interaction model.

ionx_interaction Model: Additional Notes

Note the following information when using the ionx_interaction model:

The accuracy of the unit is affected by the communication interval. If interactions are present,use at least three communication points within the shortest interacting steps.

The model uses the Delay function. Exiting Aspen Adsorption, loading a new problem or reopening, all clear the delay buffer and historical information is lost.


The Cycle Organizer defines the interaction and profile times.

The initial reverse values are used only in the first cycle.

The variables F_Initial, C_Initial and Rhol_Initial are used only in the first cycle. For

subsequent cycles, they are ignored.

ionx_mix_multi_nr Model

The ionx_mix_multi_nr is a non-reversible model that combines any number of input streams into asingle output stream.

See Also

ionx_mix_multi_nr Model: Connectivity





ionx_mix_multi_nr Model: Configuration

ionx_mix_multi_nr Model: Specifications

ionx_mix_multi_nr Model: Initialization

ionx_mix_multi_nr Model: User Procedures Used

ionx_mix_multi_nr Model: Results

ionx_mix_multi_nr Model: Connectivity

These are the available connections for the ionx_mix_multi_nr model:

ionx_mix_multi_nr Model: Configuration

No configuration options are available for the ionx_mix_multi_nr model.

ionx_mix_multi_nr Model: Specifications

There are no variables to specify for the ionx_mix_multi model.

ionx_mix_multi_nr Model: Initialization

No initialization method is required for the ionx_mix_multi_nr model.

ionx_mix_multi_nr Model: User ProceduresUsed

There are no user procedures available for the ionx_mix_multi-nr model.

Port Name Type Valid ConnectionProcess_In i_material_port (multiport) ionx_Material_Connection






ionx_mix_multi_nr Model: Results

Typical variables in the Results table for the ionx_mix_multi_nr model are:

ionx_mix_nr2 Model

The ionx_mix_nr2 model is a non-reversible model that selects an output stream from one of twoinput streams.

See Also

ionx_mix_nr2 Model: Connectivity

ionx_mix_nr2 Model: Configuration

ionx_mix_nr2 Model: Specifications

ionx_mix_nr2 Model: Initialization

ionx_mix_nr2 Model: User Procedures Used

ionx_mix_nr2 Model: Results


These are the available connections for the ionx_mix_nr2 model:


No configuration options are available for the ionx_mix_nr2 model.


Process_Out.F Volumetric flowrate of outletProcess_Out.C Ion concentration of outlet

Process_Out.Rhol Bulk molar density of outlet

Port Name Type Valid ConnectionProcess_In1 i_material_port (single) ionx_Material_Connection








Depending on how the ionx_fmix_nr2 model has been configured, you need to specify this variablein the Specify table:


No initialization method is required for the ionx_mix_nr2 model.


There are no user procedures available for the ionx_mix_nr2 model.


Typical variables in the Results table for the ionx_mix_nr2 model are:

ionx_mix_nr3 Model

The ionx_mix_nr2 model is a non-reversible model that selects an output stream from one of threeinput streams.

See Also


Variable DescriptionMode Input stream selection:

1 = Process_In1

2 = Process_In2


Process_In1.F Inlet 1 volumetric flowrate


Process_Out1.F Outlet volumetric flowrate

Process_Out1.C Outlet bulk ion concentration

Process_Out1.Rhol Outlet bulk molar density











These are the available connections for the ionx_mix_nr3 model:


No configuration options are available for the ionx_mix_nr3 model.


Depending on how the ionx_mix_nr3 model has been configured, you need to specify this variable inthe Specify table:

ionx_mix_nr3 Model: Initialization No initialization method is required for the ionx_mix_nr3 model.






Mode Input stream selection:

1 = Process_In1

2 = Process_In2

3 = Process_In3






There are no user procedures available for the ionx_mix_nr3 model.


Typical variables in the Results table for the ionx_mix_nr3 model are:

ionx_prod_distrib Model

Use the ionx_prod_distrib model as a four-way valve within an ion-exchange flowsheet. The model

is reversible and contains two inlet and two outlet ports.

See Also

ionx_prod_distrib Model: Connectivity

ionx_prod_distrib Model: Configuration

ionx_prod_distrib Model: Specifications

ionx_prod_distrib Model: Initialization

ionx_prod_distrib Model: User Procedures Used

ionx_prod_distrib Model: Results

ionx_prod_distrib Model: Additional Notes

ionx_prod_distrib Model: Connectivity

These are the available connections for the ionx_prod_distrib model:




Process_In3.F Inlet 3 volumetric flowrateProcess_Out1.F Outlet volumetric flowrate

Process_Out1.C Outlet bulk ion concentration

Process_Out1.Rhol Outlet bulk molar density





ionx_prod_distrib Model: Configuration

No configuration options are available for the ionx_prod_distrib model.

ionx_prod_distrib Model: Specifications

Depending on how the ionx_prod_distrib model has been configured, you need to specify one or more of these variables in the Specify table:

ionx_prod_distrib Model: Initialization

No initialization method is required for the ionx_prod distrib model.

ionx_prod_distrib Model: User Procedures

Used

There are no user procedures available for the ionx_prod_distrib model.







Mode Distribution setting:

1 = Process_In1 and Process_Out1 connected andflowrate set to Flow. Zero flow for other streams.

2 = Process_In1 and Process_In2 connected.

Process_Out1 and Process_Out2 set to zero flow.

3 = Process_In1 and Process_Out2 connected.Process_In2 and Process_Out1 set to zero flow.

Flow Nominal volumetric flowrate





ionx_prod_distrib Model: Results

Typical variables in the Results table for the ionx_prod_distrib model are:

ionx_prod_distrib Model: Additional Notes

Note the following information when using the ionx_prod_distrib model:

The flow in stream Process_Out1 may reverse.

Typically, stream Process_In1 connects to a bed and Process_In1 conects to a feed unit.

The stream Process_Out2 is typically attached to an interaction unit.

ionx_product Model

Use the ionx_product model to terminate an outlet/product flowsheet boundary. If configured as areversible model, and should the flow reverse, it acts as a feed unit, providing information on ionconcentration and bulk molar density.

See Also

ionx_product Model: Connectivity

ionx_product Model: Configuration

ionx_product Model: Specifications

ionx_product Model: Initialization

ionx_product Model: User Procedures Used

ionx_product Model: Results

ionx_product Model: ConnectivityThese are the available connections for the ionx_product model:









ionx_product Model: ConfigurationThese are the configuration options available for the ionx_product model:

ionx_product Model: Specifications

Depending on how the ionx_product model has been configured, you need to specify one or more of these variables in the Specify table:

ionx_product Model: Initialization

No initialization method is required for the ionx_product model.

ionx_product Model: User Procedures Used

There are no user procedures available for the ionx_product model.

ionx_product Model: Results






Non-Reversible



False

Enable boundary accumulationterms for material balance

reporting


Model

C_Rev Ion concentration in reversedirection

Reversible model

Rhol_Rev Bulk molar density in reverse

direction

Reversible model





Typical variables in the Results and Reports tables for the ionx_product model are:

ionx_split_nr2 Model

The ionx_split_nr2 is a non-reversible model that diverts an input stream to one of two output

streams.

See Also

ionx_split_nr2 Model: Connectivity

ionx_split_nr2 Model: Configuration

ionx_split_nr2 Model: Specifications

ionx_split_nr2 Model: Initialization

ionx_split_nr2 Model: User Procedures Used

ionx_split_nr2 Model: Results

ionx_split_nr2 Model: Connectivity

These are the available connections for the ionx_split_nr2 model:

ionx_split_nr2 Model: Configuration

No configuration options are available for the ionx_split_nr2 model.


F_In Volumetric flowrate Non-reversible model


C_In Ion concentration Non-reversible modelC_Rev Ion concentration Reversible model

Rhol_In Bulk molar density Non-reversible model

Rhol_Rev Bulk molar density Reversible model









ionx_split_nr2 Model: Specifications

Depending on how the ionx_split_nr2 model has been configured, you need to specify this variablein the Specify table:

ionx_split_nr2 Model: Initialization No initialization method is required for the ionx_split_nr2 model.

ionx_split_nr2 Model: User Procedures Used

There are no user procedures available for the ionx_split_nr2 model.

ionx_split_nr2 Model: Results

Typical variables in the Results table for the ionx_split_nr2 model are:

ionx_valve_nr Model

The ionx_valve_nr is a non-reversible model that controls the flowrate of an inlet stream.

See Also

ionx_valve_nr Model: Connectivity

ionx_valve_nr Model: Configuration


Mode Output stream selection:

1 = Process_Out1

2 = Process_Out2



Process_Out1.F Outlet 1 volumetric flowrate






ionx_valve_nr Model: Specifications

ionx_valve_nr Model: Initialization

ionx_valve_nr Model: User Procedures Used

ionx_valve_nr Model: Results

ionx_valve_nr Model: Additional Notes

ionx_valve_nr Model: Connectivity

These are the available connections for the ionx_valve_nr model:

ionx_valve_nr Model: Configuration

No configuration options are available for the ionx_valve_nr model.

ionx_valve_nr Model: Specifications

Depending on how the ionx_valve_nr model has been configured, you need to specify one or moreof these variables in the Specify table:

ionx_valve_nr Model: Initialization

No initialization method is required for the ionx_valve_nr model.




Action_Specification Valve operation setting

0 = Fully off

1 = Used defined volumetric flowrate

Flowrate Outlet volumetric flowrate (used whenAction_Specification = 1)





ionx _valve_nr Model: User Procedures Used

There are no user procedures available for the ionx_valve_nr model.

ionx _valve_nr Model: Results

Typical variables in the Results table for the ionx_valve_nr model are:

ionx _valve_nr Model: A dditional Notes

Note the following information when using the ionx_valve_nr model:

The variable Flowrate is used only when Action_Specification is set to 1, otherwise it isignored.

Liq uid Models

The table lists the liquid phase models available in Aspen Adsorption. You connect these modelsusing the liq_Material_Connection stream.

liq _bed Model


Process_In1.F Volumetric flowrate of inlet stream

Process_In1.C Ion concentration of inlet stream

Model Description

liq_bed Adsorbent bed layers

liq_feed Feed/inlet boundary terminator

liq_feed_distrib Connects outlet to 1 of 2 inlet streams

liq_heat_exchanger General instantaneous heat exchanger

liq_interaction Pseudo bed for single bed approach

liq_mix_multi Multiple inlet stream mixer

liq_prod_distrib Diverts input to 1 of 3 outlets

liq_product Product/outlet boundary terminator

liq_split Diverts inlet to 1 of 2 outlets

liq_tank Accounts for spaces/holdup

liq_valve Relates pressure drop to flowrate





The liq_bed model simulates a liquid adsorption bed unit in a liquid flowsheet. It acts as a container

model for the adsorbent layers and their interconnections.

See Also

liq_bed Model: Connectivity

liq_bed Model: Configuration

liq_bed Model: Specifications

liq_bed Model: Initialization

liq_bed Model: User Procedures Used

liq_bed Model: Results

liq_bed Model: Additional Notes

liq _bed Model: Connectivity

These are the available connections for the liq_bed model:

liq _bed Model: Configuration

This is the configuration option available for the liq_bed model:

liq _bed Model: Specifications

No specifications are required for the liq_bed model, but each adsorbent layer has its ownspecifications.

liq _bed Model: Initialization


Process_In liq_material_port (single) liq_Material_Connection

Process_Out liq_material_port (single) liq_Material_Connection


Number of layers Integer (1 or higher) Number of independent

adsorbent layers with the bed





No initialization method is required for the liq_bed model, but each contained layer needs

initializing.

liq _bed Model: User Procedures Used

There are no user procedures available for the liq_bed model.

liq _bed Model: Results

There are no recommended results for the liq_bed model.

liq _bed Model: A dditional Notes

Note the following information when using the liq_bed model:


The model does not include any inlet or outlet dead space.

The model behavior is reversible, so distributors or feed and product units must be connectedat each end.

liq _feed Model

The liq_feed model terminates an inlet/feed flowsheet boundary. Use it to specify the materialcomposition, temperature and pressure. If configured as a reversible model, and should the flowreverse, it acts as a product sink.

See Also

liq_feed Model: Connectivity

liq_feed Model: Configuration

liq_feed Model: Specifications

liq_feed Model: Initialization

liq_feed Model: User Procedures Used

liq_feed Model: Results





liq_feed Model: Additional Notes

liq _feed Model: Connectivity

These are the available connections for the liq_feed model:

liq _feed Model: Configuration

These are the configuration options available for the liq_feed model:

liq _feed Model: Specifications

Depending on how the liq_feed model has been configured, you need to specify one or more of these

variables in the Specify table:

liq _feed Model: Initialization






Non-Reversible



False



Model

C_Out Component concentration of stream


T_Out Temperature of stream Non-reversible model

P_Out Pressure at boundary Non-reversible model

C_Fwd Component concentration of stream in forward direction

Reversible model

T_Fwd Temperature of stream in

forward direction

Reversible model






No initialization method is required for the liq_feed model.

liq_feed Model: User Procedures Used

Depending on the model configuration, this user procedures is available for the liq_feed model:

liq_feed Model: Results

Typical variables in the Results and Reports tables for the liq_feed model are:


pUser_l_Enthalpy_Mol Molar enthalpy (user Fortran physical properties)


F_Out Volumetric flowrate Non-reversible model


C_Rev Component concentration inreverse direction

Reversible model

T_Rev Stream temperature in reversedirection

Reversible model

H_Rev Stream enthalpy in reverse

direction

Reversible model

Total_Material Total material fed into boundary Non-reversible model

Total_Material_Fwd Total material fed into boundary Reversible model

Total_Material_Rev Total material received at boundary

Reversible model

Total_Component Total component fed into boundary


Total_Component_Fwd Total component fed into boundary

Reversible model

Total_Component_Rev Total component received at

boundary

Reversible model

Avg_Composition Total average composition of component fed into boundary


Avg_Composition_Fwd Total average composition of component fed into boundary

Reversible model

Avg_Composition_Rev Total average composition of component received at boundary

Reversible model

Total_Energy Total energy fed into boundary Non-reversible model

Total_Energy_Fwd Total energy fed into boundary Reversible model

Total_Energy_Rev Total energy received at boundary

Reversible model

Cycle_Total_Material Total material fed into boundaryfor last cycle


Cycle_Total_Material_Fwd Total material fed into boundary Reversible model





liq_feed Model: Additional Notes Note the following information when using the liq_feed model:

For forced feed (fixed material flowrate, no valve fitted to the outlet), it is valid to specifyF_Out or F_Fwd as Fixed.

At low flow conditions, where the absolute value of the flowrate is less than or equal to theresidual tolerance, the information in the Report table is inaccurate.

liq_feed_distrib Model

The liq_feed_distrib model selects an output stream from one of two input streams. The model isnon-reversible.

See Also

liq_feed_distrib Model: Connectivity

liq_feed_distrib Model: Configuration

liq_feed_distrib Model: Specifications

for last cycle

Cycle_Total_Material_Rev Total material received at boundary for last cycle

Reversible model

Cycle_Total_Component Total component fed into boundary for last cycle


Cycle_Total_Component_Fwd Total component fed into


Reversible model

Cycle_Total_Component_Rev Total component received at boundary for last cycle

Reversible model

Cycle_Avg_Composition Total average composition of component fed into boundary for last cycle


Cycle_Avg_Composition_Fwd Total average composition of component fed into boundary for last cycle

Reversible model

Cycle_Avg_Composition_Rev Total average composition of component received at boundary

for last cycle

Reversible model

Cycle_Total_Energy Total energy fed into boundaryfor last cycle


Cycle_Total_Energy_Fwd Total energy fed into boundaryfor last cycle

Reversible model

Cycle_Total_Energy_Rev Total energy received at boundary for last cycle

Reversible model





liq_feed_distrib Model: Initialization

liq_feed_distrib Model: User Procedures Used

liq_feed_distrib Model: Results

liq_feed_distrib Model: Connectivity

These are the available connections for the liq_feed_distrib model:

liq_feed_distrib Model: Configuration

No configuration options are available for the liq_feed_distrib model.

liq_feed_distrib Model: SpecificationsDepending on how the liq_feed_distrib model has been configured, you need to specify this variablein the Specify table:

liq_feed_distrib Model: Initialization

No initialization method is required for the liq_feed_distrib model.

liq_feed_distrib Model: User Procedures UsedThere are no user procedures available for the liq_feed_distrib model.


Process_In1 liq_material_port (single) liq_Material_Connection


Process_Out1 liq_material_port (single) liq_Material_Connection


Mode Inlet stream selection:

1 = Process_In1

2 = Process_In2





liq_feed_distrib Model: Results

Typical variables in the Results table for the liq_feed_distrib model are:

liq_heat_exchanger Model

The liq_heat_exchanger model modifies the temperature of an inlet stream. By default, it operates ata constant outlet temperature. You can change the model operation to either constant duty or constant temperature rise/drop. The model is of type non-reversible.

See Also

liq_heat_exchanger Model: Connectivity

liq_heat_exchanger Model: Configuration

liq_heat_exchanger Model: Specifications

liq_heat_exchanger Model: Initialization

liq_heat_exchanger Model: User Procedures Used

liq_heat_exchanger Model: Results

liq_heat_exchanger Model: Connectivity

These are the available connections for the liq_heat_exchanger model:


Process_In1.F Volumetric flowrate of inlet stream 1


Process_Out1.F Volumetric flowrate of outlet stream

Process_Out1.C Molar concentration of outlet stream

Process_Out1.T Temperature of outlet stream

Process_Out1.P Pressure of outlet stream

Process_Out1.H Specific enthalpy of outlet stream


Process_In g_material_port (single) liq_Material_Connection

Process_Out g_material_port (single) liq_Material_Connection





liq_heat_exchanger Model: Configuration

No configuration options are available for the liq_heat_exchanger model.

liq_heat_exchanger Model: Specifications

Depending on how the liq_heat_exchanger model has been configured, you need to specify one or more of these variables in the Specify table:

liq_heat_exchanger Model: Initialization

No initialization method is required for the liq_heat_exchanger model.

liq_heat_exchanger Model: User Procedures

Used

One user procedure is available for the liq_heat_exchanger model as follows:

Note: This procedure is for user-Fortran liquid molar enthalpy calculation.

liq_heat_exchanger Model: Results

Typical variables in the Results table for the liq_heat_exchanger model are:


Heat_Exchange_Area Composition of stream (non-reversible model)

U Overall heat transfer coefficient


T_Fluid Temperature of heat exchange fluid


T_Change Temperature rise/drop of process stream

P_Drop Constant average pressure drop

User Procedure Description pUser_l_Enthalpy_Mol Liquid Molar enthalpy







liq_interaction Model

Use the liq_interaction model as part of the single bed modeling approach to record the profile of material received, then later replay this profile to simulate returned material. The followinginformation is recorded over time:

Volumetric flowrate

Molar concentration

Temperature

Pressure

Specific enthalpy

Any type of bed interaction can be defined:

Top-to-top

Top-to-bottom

Bottom-to-bottom

Bottom-to-top

You define the interaction type through the connectivity (where material is accepted from, andreturned to). During runtime, you cannot redefine the interaction type as connectivity is structural, so

if you want more than one type of interaction, use additional interaction models

By acting as a pseudo adsorbent bed, it is possible for the model to behave as a bed at either constantor varying pressure. The Cycle Organizer defines the steps between successive interactions.

See Also

liq_interaction Model: Connectivity

liq_interaction Model: Configuration

liq_interaction Model: Specifications

liq_interaction Model: Initialization

liq_interaction Model: User Procedures Used

liq_interaction Model: Results

liq_interaction Model: Additional Notes


T_Change Temperature rise/drop





liq_interaction Model: Connectivity

These are the available connections for the liq_interaction model:

liq_interaction Model: Configuration

No configuration options are available for the liq_interaction model.

liq_interaction Model: Specifications

Depending on how the liq_interaction model has been configured, you need to specify one or moreof these variables in the Specify table:

Note: All these variables are used in the first cycle.

liq_interaction Model: Initialization

No initialization method is required for the liq_interaction model.

liq_interaction Model: User Procedures Used

Depending on the model configuration, the user procedure available for the liq_interaction model is:





F_Initial Average flowrate of returned material during a

reverse interactionC_Initial Average concentration of returned material during

a reverse interaction

T_Initial Average temperature of material during a reverseinteraction

P_Initial Average pressure of material during a reverse

interaction






liq_interaction Model: Results

There are no recommended results for the liq_interaction model.

liq_interaction Model: Additional Notes

Note the following information when using the liq_interaction model:

The accuracy of the unit is affected by the communication interval. If interactions are present,

use at least three communication points within the shortest interacting steps.

The model uses the Delay function. Exiting Aspen Adsorption, loading a new problem or reopening, all clear the delay buffer and historical information is lost.

Each interaction unit handles multiples interacting pairs.

The Cycle Organizer defines the interaction and profile times.

The initial reverse values are used only in the first cycle.

The variables F_Initial, C_Initial, T_Initial and P_Initial are used only in the first cycle. For subsequent cycles, they are ignored.

liq_mix_multi Model

The liq_mix_multi_nr is a non-reversible model that combines any number of input streams into asingle output stream.

See Also

liq_mix_multi Model: Connectivity

liq_mix_multi Model: Configuration

liq_mix_multi Model: Specifications

liq_mix_multi Model: Initialization

liq_mix_multi Model: User Procedures Used

liq_mix_multi Model: Results






liq_mix_multi Model: Connectivity

These are the available connections for the liq_mix_multi model:

liq_mix_multi Model: Configuration

No configuration options are available for the liq_mix_multi model.

liq_mix_multi Model: Specifications

There are no variables to specify in the liq_mix_multi model.

liq_mix_multi Model: Initialization No initialization method is required for the liq_mix_multi model.

liq_mix_multi Model: User Procedures Used

There are no user procedures available for the liq_mix_multi model.

liq_mix_multi Model: Results

Typical variables in the Results table for the liq_mix_multi model are:


Process_In liq_material_port (multiport) liq_Material_Connection



Process_Out1.F Volumetric flowrate of outlet

Process_Out1.C Component concentration of outlet

Process_Out1.T Temperature of outlet

Process_Out1.P Pressure of outlet

Process_Out1.H Specific enthalpy of outlet





liq_prod_distrib Model

The liq_prod_distrib model selects an output stream from one of three input streams. The model isnon-reversible.

See Also

liq_prod_distrib Model: Connectivity

liq_prod_distrib Model: Configuration

liq_prod_distrib Model: Specifications

liq_prod_distrib Model: Initialization

liq_prod_distrib Model: User Procedures Used

liq_prod_distrib Model: Results

liq_prod_distrib Model: Connectivity

These are the available connections for the liq_prod_distrib model:

liq_prod_distrib Model: Configuration

No configuration options are available for the liq_prod_distrib model.

liq_prod_distrib Model: Specifications

Depending on how the liq_prod_distrib model has been configured, you need to specify this variablein the Specify table:







Mode Input stream selection:





liq_prod_distrib Model: Initialization

No initialization method is required for the liq_prod_distrib model.

liq_prod_distrib Model: User Procedures Used

There are no user procedures available for the liq_prod_distrib model.

liq_prod_distrib Model: Results

Typical variables in the Results table for the liq_prod_distrib model are:

liq_product Model

The liq_product model terminates an outlet/product flowsheet boundary. Use it to receive materialfrom the flowsheet. If configured as a reversible model, and should the flow reverse, the model actsas a feed unit. You can define the material composition and material temperature.

See Also

liq_product Model: Connectivity

liq_product Model: Configuration

liq_product Model: Specifications

1 = Process_In1

2 = Process_In2

3 = Process_In3




Process_Out1.F Volumetric flowrate of outlet stream

Process_Out1.C Component concentration of outlet stream

Process_Out1.T Temperature of outlet stream

Process_Out1.P Pressure of outlet stream

Process_Out1.H Specific enthalpy of outlet stream





liq_product Model: Initialization

liq_product Model: User Procedures Used

liq_product Model: Results

liq_product Model: Additional Notes

liq_product Model: Connectivity

This is the only available connection for the liq_product model:

liq_product Model: Configuration

These are the configuration options available for the liq_product model:

liq_product Model: Specifications

Depending on how the liq_product model has been configured, you need to specify one or more of

these variables in the Specify table:





Non-Reversible



False



P_In Pressure at boundary (non-reversible model)


C_Rev Component concentration of stream in reverse direction

Reversible model

T_Rev Temperature of stream in reversedirection

Reversible model

P Pressure at boundary (reversiblemodel) Reversible model





liq_product Model: Initialization

No initialization method is required for the liq_product model.

liq_product Model: User Procedures Used

Depending on the model configuration, the user procedure available for the liq_product model is:

liq_product Model: Results

Typical variables in the Results and Reports tables for the liq_product model are:


pUser_l_Enthalpy_Mol Molar enthalpy (user Fortran physical properties,reversible model)


F_In Volumetric flowrate Non-reversible model


C_Fwd Stream component concentration Reversible model

T_Fwd Stream temperature Reversible modelH_Fwd Stream specific enthalpy Reversible model

Total_Material Total material received at boundary


Total_Material_Fwd Total material received at boundary

Reversible model

Total_Material_Rev Total material fed into boundary Reversible model

Total_Component Total component received at boundary


Total_Component_Fwd Total component received at

boundary (reversible model)

Reversible model

Total_Component_Rev Total component fed into boundary

Reversible model

Avg_Composition Total average composition of component received at boundary


Avg_Composition_Fwd Total average composition of

component received at boundary

Reversible model

Avg_Composition_Rev Total average composition of component fed into boundary

Reversible model

Total_Energy Total energy received at boundary


Total_Energy_Fwd Total energy received at boundary

Reversible model

Total_Energy_Rev Total energy fed into boundary Reversible model





liq_product Model: Additional Notes

Note the following information when using the liq_product model:

At low flow conditions, where the absolute value of the flowrate is less than or equal to the

residual tolerance, the information in the Report table is inaccurate.

liq_split Model

The liq_split model diverts an input stream to one of two output streams. The model is non-

reversible.

See Also

liq_split Model: Connectivity

liq_split Model: Configuration

liq_split Model: Specifications

Cycle_Total_Material Total material received at



Cycle_Total_Material_Fwd Total material received at boundary for last cycle

Reversible model

Cycle_Total_Material_Rev Total material fed into boundaryfor last cycle

Reversible model

Cycle_Total_Component Total component received at boundary for last cycle


Cycle_Total_Component_Fwd Total component received at boundary for last cycle

Reversible model

Cycle_Total_Component_Rev Total component fed into boundary for last cycle

Reversible model

Cycle_Avg_Composition Total average composition of component received at boundaryfor last cycle


Cycle_Avg_Composition_Fwd Total average composition of component received at boundary

for last cycle

Reversible model

Cycle_Avg_Composition_Rev Total average composition of component fed into boundary for last cycle

Reversible model

Cycle_Total_Energy Total energy received at boundary for last cycle


Cycle_Total_Energy_Fwd Total energy received at boundary for last cycle

Reversible model

Cycle_Total_Energy_Rev Total energy fed into boundaryfor last cycle

Reversible model





liq_split Model: Initialization

liq_split Model: User Procedures Used

liq_split Model: Results

liq_split Model: Connectivity

These are the available connections for the liq_split model:

liq_split Model: Configuration

No configuration options are available for the liq_split model.

liq_split Model: SpecificationsDepending on how the liq_split model has been configured, you need to specify this variable in theSpecify table:

liq_split Model: Initialization

No initialization method is required for the liq_split model.

liq_split Model: User Procedures UsedThere are no user procedures available for the liq_split model.






Mode Output stream selection:

1 = Process_Out1

2 = Process_Out2





liq_split Model: Results

Typical variables in the Results table for the liq_split model are:

liq_tank Model

The liq_tank model is a general purpose model that simulates adsorbent bed deadspaces (voids) or intermediate tanks.

See Also

liq_tank Model: Connectivity

liq_tank Model: Configuration

liq_tank Model: Specifications

liq_tank Model: Initialization

liq_tank Model: User Procedures Used

liq_tank Model: Results

liq_tank Model: Additional Notes

liq_tank Model: ConnectivityThese are the available connections for the liq_tank model:

liq_tank Model: ConfigurationThis is the configuration option available for the liq_tank model:












liq_tank Model: Specifications

Depending on how the liq_tank model has been configured, you need to specify this variable in the

Specify table:

liq_tank Model: Initialization

The recommended variables to initialize for the liq_tank model are:

liq_tank Model: User Procedures Used

Depending on the model configuration, the user procedures available for the liq_tank model are:

liq_tank Model: Results

Typical variables in the Results table for the liq_tank model are:



Non-Reversible





C Initial/RateInitial Internal componentconcentrations





Process_In.F Inlet volumetric flowrate

Process_Out.F Outlet volumetric flowrate

C Internal component concentration

T Internal temperatureH Internal specific enthalpy





liq_tank Model: Additional Notes

Note the following information when using the liq_tank model:

By default, the model behaves as a reversible model.

liq_valve Model

The liq_valve model simulates a simple linear valve that relates flowrate to the pressure differenceacross the unit.

See Also

liq_valve Model: Connectivity

liq_valve Model: Configuration

liq_valve Model: Specifications

liq_valve Model: Initialization

User Procedures Used

liq_valve Model: Results

liq_valve Model: Additional Notes

liq_valve Model: Connectivity

These are the available connections for the liq_valve model:

liq_valve Model: Configuration

These are the configuration options available for the liq_valve model:





Model type Non-Reversible Mode of flowsheet interactivity





liq_valve Model: Specifications

Depending on how the liq_valve model has been configured, you need to specify one or more of

these variables in the Specify table:

liq_valve Model: Initialization

No initialization method is required for the liq_valve model.

liq_valve User Procedures Used

There are no user procedures available for the liq_valve model.

liq_valve Model: ResultsTypical variables in the Results table for the liq_valve model are:

Reversible


Yes

For a reversible model, does theunit also act as a non-return/check valve


Active_Specification Define which of the following specifications will be used:

0 = Valve fully off

1 = Valve fully on (acts as a valve with high Cv)

2 = Make use of the value specified for Cv(constant Cv)

3 = Make use of the value specified for Flowrate(constant flowrate)

The specification can be changed during runtime

Cv Linear valve coefficient (only used whenActive_Specification = 2)

Flowrate Constant forced flowrate (only used when

Active_Specification = 3)





liq_valve Model: Additional Notes

Note the following information when using the liq_valve model:

The control action can be any real number from 0 to 1.

Miscellaneous Models

The table lists the miscellaneous models available in Aspen Adsorption:

Dynamics_Inlet_Connect Model

The Dynamics_Inlet_Connect model connects an Aspen Plus Dynamics model to the inlet of

either a gas or liquid Aspen Adsorption model. The block maps appropriate variables from the

Aspen Plus Dynamics port to the Aspen Adsorption port, taking into account differences in the portvariables, units of measurement and reversible stream conventions. Furthermore, for compatabilitywith Aspen Adsorption's single bed approach for modelling multi-bed systems using a single bed,

you can activate additional expressions to allow the block to simulate pseudo continuously flow atthe Aspen Adsorption flowsheet boundary.


Cv_Calculated Equivalent linear valve Cv

Flowrate_Calculated Flowrate through the valve

P_Change Pressure change across the valve

Control_Action External controller action applied

Model Description

Dynamics_Inlet_Connect Used to link an Aspen Plus Dynamics model tothe inlet of an Aspen Adsorption model (gas or liquid phase only)

Dynamics_Outlet_Connect Used to link an Aspen Plus Dynamics model tothe outlet of an Aspen Adsorption model (gas or

liquid phase only)

gCSS_FromGasStream_Connect Used to link an Aspen Adsorption Gas model tothe inlet of an Aspen Adsorption gCSS model.

gCSS_ToGasStream_Connect Used to link an Aspen Adsorption Gas model to

the outlet of an Aspen Adsorption gCSS model.

p_control Proportional controller

PID control PID controller

ratio Ratio block for controllers

Static_Isotherm Container model for standard isotherms

universal_block Dummy connectivity block





See Also

Dynamics_Inlet_Connect Model: Connectivity

Dynamics_Inlet_Connect Model: Configuration

Dynamics_Inlet_Connect Model: Specifications

Dynamics_Inlet_Connect Model: Initialization

Dynamics_Inlet_Connect Model: User Procedures Used

Dynamics_Inlet_Connect Model: Results

Dynamics_Inlet_Connect Model: Additional Notes

Dynamics_Inlet_Connect Model: Connectivity

These are the available connections for the Dynamics_Inlet_Connect model:

Only one of the two possible output ports can be active, so your Aspen Plus Dynamics stream canconnect to a gas or liquid Aspen Adsorption model, but not both.

Dynamics_Inlet_Connect Model:Configuration

These are the configuration options available for the Dynamics_Inlet_Connect model:


In_F MaterialPortRev (single) MaterialStream (from AspenPlus Dynamics)

gas_Process_Out g_material_port (single) gas_Material_Connection

liq_Process_Out liq_material_port (single) liq_Material_Connection


Dynamics Property Mode Local

Rigorous

Physical property methodassumed by Aspen PlusDynamics models present in theflowsheet.

All Aspen Adsorption modelsassume Rigorous physical

property calls.

Is Dynamics Pressure Driven Checked or Unchecked Check when the Aspen PlusDynamics models are pressure-driven. Uncheck when they are





All these options are global. The changes are also reflected in the Globals table found in theSimulation Explorer window.

Dynamics_Inlet_Connect Model: Specifications

Depending on how the Dynamics_Inlet_Connect model has been configured, you need to specifythis variable in the Specify table.

Dynamics_Inlet_Connect Model: Initialization No initialization method is required for the Dynamics_Inlet_Connect model.

Dynamics_Inlet_Connect Model: UserProcedures Used

There are no user procedures available for the Dynamics_Inlet_Connect model.

flowrate-driven

Is Dynamics Reverse Flow Checked or Unchecked This applies to pressure drivenAspen Plus Dynamics models.

Check when reverse flowcharacteristics are required

within the Aspen Plus Dynamicsmodels

Single Bed Approach Used Checked or Unchecked Check when the AspenAdsorption flowsheet uses thesingle bed approach to simulate amulti-column system


Mode Active only when Aspen Adsorption uses thesingle bed approach. Toggle this variable between0 and 1:

0 Indicates that no real material is passing theflowsheet boundary, so a pseudo flow profile isrequired

1 Indicates that real material is passing theflowsheet boundary





Dynamics_Inlet_Connect Model: Results

There are no results available for the Dynamics_Inlet_Connect model.

Dynamics_Inlet_Connect Model: AdditionalNotes

Note the following information when using the Dynamics_Inlet_Connect model:

Only a single outlet can be active (either gas or liquid)

Specifically when using the single bed approach:

The delay function generates pseudo continuous flow through the Aspen Plus Dynamics port.Because of the intrinsic behaviour of the delay function, some degradation in the results may

be experienced.

Aspen Adsorption calculates the delay time that is needed to generate pseudo continuous flowas follows:

It determines the time difference between when the Mode variable switches from 0 to 1, and from 1to 0. Remember that 1 is used to indicate real flow to the Aspen Adsorption model.

For more information, see Connecting to Aspen Plus Dynamics Flowsheets.

Dynamics_Outlet_Connect Model

The Dynamics_Outlet_Connect model connects an Aspen Plus Dynamicsmodel to the outlet of

either a gas or liquid Aspen Adsorption model. The block maps appropriate variables from theAspen Plus Dynamics port to the Aspen Adsorption port, taking into account differences in the portvariables, units of measurement and reversible stream conventions. Furthermore, for compatability

with Aspen Adsorption's single bed approach for modelling multi-bed systems using a single bed,you can activate additional expressions to allow the block to simulate pseudo continuously flow atthe Aspen Adsorption flowsheet boundary.

See Also

Dynamics_Outlet_Connect Model: Connectivity

Dynamics_Outlet_Connect Model: Configuration

Dynamics_Outlet_Connect Model: Specifications

Dynamics_Outlet_Connect Model: Initialization





Dynamics_Outlet_Connect Model: User Procedures Used

Dynamics_Outlet_Connect Model: Results

Dynamics_Outlet_Connect Model: Additional Notes

Dynamics_Outlet_Connect Model:Connectivity

These are the available connections for the Dynamics_Outlet_Connect model:

Only one of the two possible input ports can be active, so your Aspen Plus Dynamics stream can be connected to a gas or liquid Aspen Adsorption model, but not both.

Dynamics_Outlet_Connect Model:

Configuration

These are the configuration options available for the Dynamics_Outlet_Connect model:


Out_P MaterialPortRev (single) MaterialStream (from Aspen

Plus Dynamics)gas_Process_In g_material_port (single) gas_Material_Connection

liq_Process_In liq_material_port (single) liq_Material_Connection


Dynamics Property Mode Local

Rigorous

Physical property methodassumed by Aspen PlusDynamics models present in theflowsheet.

All Aspen Adsorption modelsassume Rigorous physical

property calls.

Is Dynamics Pressure Driven Checked or Unchecked Check when the Aspen PlusDynamics models are pressure-driven. Uncheck when they areflowrate-driven

Is Dynamics Reverse Flow Checked or Unchecked This applies to pressure drivenAspen Plus Dynamics models.

Check when reverse flow

characteristics are requiredwithin the Aspen Plus Dynamicsmodels





All these options are global. The changes are also reflected in the Globals table found in the

Simulation Explorer window.

Dynamics_Outlet_Connect Model:

Specifications

Depending on how the Dynamics_Outlet_Connect model has been configured, you need to specifythis variable in the Specify table.

Dynamics_Outlet_Connect Model:Initialization

No initialization method is required for the Dynamics_Outlet_Connect model.

Dynamics_Outlet_Connect Model: UserProcedures Used

There are no user procedures available for the Dynamics_Outlet_Connect model.

Dynamics_Outlet_Connect Model: Results

Single Bed Approach Used Checked or Unchecked Check when the Aspen

Adsorption flowsheet uses thesingle bed approach to simulate amulti-column system


Mode Active only when Aspen Adsorption uses thesingle bed approach. Toggle this variable between0 and 1:

0 Indicates that no real material is passing theflowsheet boundary, so a pseudo flow profile isrequired

1 Indicates that real material is passing the

flowsheet boundary





There are no results available for the Dynamics_Outlet_Connect model.

Dynamics_Outlet_Connect Model: Additional

Notes Note the following information when using the Dynamics_Outlet_Connect model:

Only a single outlet can be active (either gas or liquid)

Specifically when using the single bed approach:

The delay function is used to generate pseudo continuous flow through the Aspen PlusDynamics port. Because of the intrinsic behaviour of the delay function, some degradation in

the results may be experienced.

Aspen Adsorption calculates the delay time that is needed to generate pseudo continuous flowas follows:

It determines the time difference between when the Mode variable switches from 0 to 1, and from 1to 0. Remember that 1 is used to indicate real flow to the Aspen Adsorption model.

For more information, see Connecting to Aspen Plus Dynamics Flowsheets.

gCSS_FromGasStream_Connect Model

The gCSS_FromGasStream_Connect model connects an Aspen Adsorption heritage gas model to theinlet of Aspen Adsorption gCSS model. The block maps appropriate variables from the heritage gasmodel’s port (g_Material_port) to the gCSS model’s port (gCSS_Port), taking into accountdifferences in the port variables, units of measurement and reversible stream conventions.

See Also

gCSS_FromGasStream_Connect Model: Connectivity

gCSS_FromGasStream_Connect Model: Configuration/Specification

gCSS_FromGasStream_Connect Model: Initialization

gCSS_FromGasStream_Connect Model: User Procedures/Submodels Used

gCSS_FromGasStream_Connect Model: Results

gCSS_FromGasStream_Connect Model: Additional Notes





gCSS_FromGasStream_Connect Model:Connectivity

These are the available connections for the gCSS_FromGasStream_Connect model:

gCSS_FromGasStream_Connect Model:Configuration/Specification

No configuration or specification procedure is required for the gCSS_FromGasStream_Connectmodel.

gCSS_FromGasStream_Connect Model:Initialization

No initialization method is required for the gCSS_FromGasStream_Connect model.

gCSS_FromGasStream_Connect Model: UserProcedures/Submodels Used

There are no user procedures available for the gCSS_FromGasStream_Connect model.

gCSS_FromGasStream_Connect Model:

Results

There are no results available for the gCSS_FromGasStream_Connect model.

gCSS_FromGasStream_Connect Model:Additional Notes

Port name Port Type Valid connection

Process_In g_Material_Port (single) gas_Material_Connection

Process_Out gCSS_ port (single) gCSS_Material_Connection





Note the following information when using the gCSS_FromGasStream_Connect model:

This model is applicable when CSS modeling flowsheet is defined in dynamic simulationmode.

gCSS_ToGasStream_Connect Model

The gCSS_ToGasStream_Connect model connects an Aspen Adsorption heritage gas model to theoutlet of Aspen Adsorption gCSS model. The block maps appropriate variables from the gCSSmodel’s port (gCSS_Port) to the heritage gas model’s port (g_Material_port), taking into accountdifferences in the port variables, units of measurement and reversible stream conventions.

See Also

gCSS_ToGasStream_Connect Model: Connectivity

gCSS_ToGasStream_Connect Model: Configuration/Specification

gCSS_ToGasStream_Connect Model: Initialization

gCSS_ToGasStream_Connect Model: User Procedures/Submodels Used

gCSS_ToGasStream_Connect Model: Results

gCSS_ToGasStream_Connect Model: Additional Notes

gCSS_ToGasStream_Connect Model:Connectivity

These are the available connections for the gCSS_ToGasStream_Connect model:

gCSS_ToGasStream_Connect Model:Configuration/Specification

No configuration or specification procedure is required for the gCSS_ToGasStream_Connect model.

Port name Port Type Valid connection

Process_In gCSS_Port (single) gCSS_Material_ConnectionProcess_Out g_Material_port (single) gas_Material_Connection





gCSS_ToGasStream_Connect Model:Initialization

No initialization method is required for the gCSS_ToGasStream_Connect model.

gCSS_ToGasStream_Connect Model: UserProcedures/Submodels Used

There are no user procedures available for the gCSS_ToGasStream_Connect model.

gCSS_ToGasStream_Connect Model: Results

There are no results available for the gCSS_ToGasStream_Connect model.

gCSS_ToGasStream_Connect Model:Additional Notes

Note the following information when using the gCSS_ToGasStream_Connect model:

This model is applicable when CSS modeling flowsheet is defined in dynamic simulationmode.

p_control model

The p_control model provides simple proportional control. The controller input is the measuredvariable, the controller output is the manipulated variable.

You can influence the controller output as follows:

Apply a clipping range

Normalize between user-defined minimum and maximum values

See Also

p_control Model: Connectivity

p_control Model: Configuration





p_control Model: Specifications

p_control Model: Initialization

p_control Model: User Procedures Used

p_control Model: Results

p_control Model: Additional Notes

p_control Model: Connectivity

These are the available connections for the p_control model:

p_control Model: Configuration

These are the configuration options available for the p_control model:

Port Name Valid ConnectionInputSignal ControlSignal

OutputSignal ControlSignal

Option Valid Values DescriptionMode Of Operation Auto

Man

Switch between automatic or manual operation. If set tomanual, the controller outputequals the Bias value.

Output Action Reverse

Direct

Reverse — to increase the inputvariable, the output variable

decreases, and vice-versa.

Direct — to increase the inputvariable, the output variable

increases, and vice-versa.

This is the opposite behavior tothe PID controller.

Apply Output Clipping Yes

No

Clip the calculated controller output between set minimum andmaximum values

Apply Output Normalization Yes

No

Normalize the calculatedcontroller output (after clippingif enabled) to set minimum andmaximum values





p_control Model: Specifications

Depending on how the p_control model has been configured, you need to specify one or more of these variables, directly on the Configure form.

p_control Model: Initialization

No initialization method is required for the p_control model.

p_control Model: User Procedures Used

There are no user procedures available for the p_control model.

p_control Model: Results

Typical variables in the Results table for the p_control model are:

p_control Model: Additional Notes Note the following information when using the p_control model:

Variable DescriptionSet Point Operator set point of controller

Bias Bias offset or manual output setting

Gain Proportional gain

Minimum Minimum value allowed for output clippingand/or output normalization

Maximum Maximum value allowed for output clippingand/or output normalization


I_In Input value

I_Out Final output value (after clipping and/or normalization)

Error Controller error (Set Point minus Input Signal)

Proportional_Band Proportional band of controller (100/Gain)

Value Calculated control output (before clipping andnormalization)

ValueC Control output after clipping (if applied)





For a Direct action controller, the controller output is calculated from:

For a reverse action controller, the output is calculated from:

For Direct action controllers, if you want the input variable to increase, then the model

increases the output variable, and similarly for decreases.

For Reverse action controllers, if you want the input variable to increase, the model decreasesthe output variable; for a decrease in the input variable, the model increases the outputvariable.

The control action is configured in the opposite way to the PID controller.

PID ModelAspen Adsorption uses the same PID model as Aspen Plus Dynamics and Aspen Custom

Modeler .

See Control Models in the Reference section of the Aspen Plus Dynamics or Aspen Custom Modeler

help.

ratio ModelThe ratio model calculates a single output as the ratio of two inputs.

The input signal comes from an external source, and the output signal goes to a manipulated externalvariable.

See Also

ratio Model: Connectivity

ratio Model: Configuration

ratio Model: Specifications

ratio Model: Initialization

ratio Model: User Procedures Used





ratio Model: Results

ratio Model: Connectivity

These are the available connections for the ratio model:

ratio Model: Configuration

There are no configuration options for the ratio model.

ratio Model: Specifications

There are no variables to specify for the ratio model.

ratio Model: Initialization

Initialization is not required for the ratio model.

ratio Model: User Procedures UsedThere are no user procedures available for the ratio model.

ratio Model: Results

The typical variable to be used for results is the output from the ratio model.

Port Name Options Valid Connection

InputSignal Input 1

Input 2

ControlSignal

OutputSignal ControlSignal





Static_Isotherm Model

The Static_Isotherm model fits isotherm parameters to static experimental data. Use it as part of Aspen Adsorption's estimation capability.

The model accesses the standard and user isotherms for the following systems:

Gas

Ion-Exchange

Liquid

See Also

Static_Isotherm Model: Connectivity

Static_Isotherm Model: Configuration

Static_Isotherm Model: Specifications

Static_Isotherm Model: Initialization

Static_Isotherm Model: User Procedures Used

Static_Isotherm Model: Results

Static_Isotherm Model: Additional Notes

Static_Isotherm Model: Connectivity

The Static_Isotherm model is a standalone unit. No connections are required.

Static_Isotherm Model: ConfigurationThese are the configuration options available for the Static_Isotherm model:


Phase to be studied Gas

IonX

Liquid

Phase of isotherm

Gas isotherm form Any valid isotherm for gasadsorbent layer model

Choice of gas phase isotherm

Gas isotherm dependency Concentration Component composition basis





Static_Isotherm Model: Specifications:

Depending on how the Static_Isotherm model has been configured, you need to specify one or moreof these variables in the Specify table:

Static_Isotherm Model: Initialization

No initialization method is required for the Static_Isotherm model.

Static_Isotherm Model: User Procedures Used

With user-procedure-based isotherm options selected, the user procedures available for theStatic_Isotherm model are:

Partial Pressure for the gas isotherm

Liquid isotherm form Any valid isotherm for liquidadsorbent layer model

Choice of liquid phase isotherm

Ion exchange isotherm form Any valid isotherm for ion

exchange adsorbent layer model

Choice of ion-exchange isotherm


Y Gas molefraction composition

C Gas phase concentration

Ci Ion concentration

Q Total resin capacity

Cl Liquid phase concentration

IP Isotherm parameters

IP_CounterIon Isotherm parameter for exchanged counter ion

Apply_IAS Apply IAS for given component when using IASisotherms

T Temperature

P Pressure


pUser_g_Isotherm_Poi Spread pressure based user isotherm

pUser_g_Gibbs Gibbs expression for user isotherm

pUser_g_Isotherm_P Partial pressure based user isotherm

pUser_g_Isotherm_W Loading based user isotherm

pUser_g_Isotherm_C Gas concentration based user isotherm

pUser_i_Isotherm_C Ion concentration based user isotherm pUser_i_Isotherm_W Ion loading based user isotherm

pUser_l_Isotherm_C Liquid concentration based user isotherm





Static_Isotherm Model: ResultsTypical variables in the Results table for the Static_Isotherm model are:

Static_Isotherm Model: Additional Notes

Note the following information when using the Static_Isotherm model:

Ideally, when running a steady-state estimation, the Static_Isotherm model should be the onlymodel on the flowsheet.

universal_block Model

The universal_block model is a simple template block that allows you to use flowsheet constraints to

create a custom model that connects with other Aspen Adsorption models.

See Also

universal_block Model: Connectivity

universal_block Model: Configuration

universal_block Model: Specifications

universal_block Model: Initialization

universal_block Model: User Procedures Used

universal_block Model: Results

universal_block Model: Additional Notes

universal_block Model: Example of Using Flowsheet Constraints

pUser_l_Isotherm_W Loading based user isotherm

pUser_l_Gibbs Gibbs expression for user isotherm


W Gas loading

Wi Ion loading

Wl Liquid loading

IP Isotherm parameters





universal_block Model: Connectivity

These are the available connections for the universal_block model:

universal_block Model: Configuration

This is the configuration option available for the universal_block model:

universal_block Model: Specifications

There are no variables to specify for the universal_block model.

universal_block Model: Initialization

No built in initialization method has been provided for the universal_block model because it is user-model dependent.


Process_In_Gas g_material_port (single) gas_Material_ConnectionProcess_In_MGas g_material_port (multi) gas_Material_Connection

Process_Out_Gas g_material_port (single) gas_Material_Connection

Process_Out_MGas g_material_port (multi) gas_Material_Connection

Process_In_IonX i_material_port (single) ionx_Material_Connection

Process_In_MIonX i_material_port (multi) ionx_Material_Connection

Process_Out_IonX i_material_port (single) ionx_Material_Connection

Process_Out_MIonX i_material_port (multi) ionx_Material_Connection

Process_In_Liq liq_material_port (single) liq_Material_Connection

Process_In_MLiq liq_material_port (multi) liq_Material_Connection

Process_Out_Liq liq_material_port (single) liq_Material_ConnectionProcess_Out_MLiq liq_material_port (multi) liq_Material_Connection


Model type Non-Reversible

Non-Reversible Delay

Reversible

Reversible Flow Setter

Reversible Pressure Setter


Note Use the Delay , Flow andPressure Setter options only for gas systems.





universal_block Model: User Procedures Used

There are no user procedures available for the universal_block model.

universal_block Model: Results

There are no recommended results for the universal_block model.

universal_block Model: Additional Notes Note the following information for the universal_block model:

The model has no equations.

You are expected to provide any expressions relating active port variables, through the use of

Flowsheet constraints.

For an example of the model's use, please refer to the Simulated Moving Bed separation of P-xylene demonstration example.

universal_block Model: Example of UsingFlowsheet Constraints

If an instance of the model, named M1, is placed on the flowsheet and is configured as non-reversible, the equations within the flowsheet constraints that make the unit act as a liquid mixer are:

//User liquid mixer block M1

// (assumes multiports are used and the model is non-reversible)

//Declare additional local variables

C_M1(ComponentList) As l_Conc_mol;

X_M1(ComponentList) As MoleFraction;

T_M1 As Temperature_K;

P_M1 As Pressure;

H_M1 As l_Enthalpy_Mol;





//Set local scope (Block M1)

Within M1

//Overall material balance (in = out)

SIGMA( Process_In_MLiq.Connection.F )

= SIGMA( Process_Out_MLiq.Connection.F );

//Loop on component list

For i In ComponentList Do

//Individual component material balance

C_M1(i) * SIGMA( Process_In_MLiq.Connection.F )

= SIGMA( Process_In_MLiq.Connection.C(i)

* Process_In_MLiq.Connection.F );//Internal material fractions (trap divide by zero)

X_M1(i) * MAX( SIGMA( C_M1(ComponentList) ), 1e-15 ) = C_M1(i);

//Non-reversible model so set outlet concentrationsProcess_Out_MLiq.Connection.C(i) = C_M1(i);

EndFor

//Inlet/outlet pressure constraintProcess_In_MLiq.Connection.P = P_M1;Process_Out_MLiq.Connection.P = P_M1;//Energy balance

H M1 * SIGMA( P I MLi C i F )


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