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CHEMICAL INDUSTRY
OPTIMIZATION
CONTENTS
- Who are we?
- Case studies:- Case 01: solid/liquid/gas reactor.
- Case 02: bubble column.
- Case 03: fluidized bed / vitrification.
- Case 04: scrubber.
- Case 05: pollutants dispersion.
- Case 06: acid-base reaction.
- Case 07: polimerization reaction (polythene).
-Contact.
MISSION
To be the reference in the sectors: Fluid-dynamics and its interactionwith structures.To be specialists in the modeling of Solid Particles.
Aeronautical Mining
Naval Agriculture
Energy Pharmaceutical
Civil Engineering Others
Chemical
HVAC
Automotive
Enviromental
Turbomachinery
Steel
Defense
Fire Safety
TARGET SECTORS
Results reflected on:• Costs reduction• Quality improvement• Increasing production• Increasing profits
Design optimizationIndustrial processes optimizationEnergetic Eficiency AnalysisContingency Analysis
(incidents/accidents)Equipment Damage Analysis
WHAT WE OFFER
• Fluid proprieties:– Liquid, water. – Gas, air bubbles: dp = 3 mm, 1.5 %v.– Solid, Catalytic converter spheres : dp= 3.7 mm, 2200 kg/m3.
• Turbulence:– Liquid: k-epsilon standard model.
• Drag Laws:– Air bubbles: Grace, turbulent dispersion, BIT.– Solid particles: Schiller Naumann, turbulent dispersion.
• Boundary conditions:– Air injector under the mixer.
Case 01
Vessel or reactor in which there are three chemical components in thethree possible states.
Gas/Liquid/Solid flow in mixers
• Rushton 4 blades turbine.• 4 baffles tank.• Rotational velocity:
– 20 to 100 rev/min.• Tank diametre 2,5 m.• Tank volume 4,9 m3.• Water/ Air / Catalyst.
Geometry:
Gas/Liquid/Solid flow in mixers
• Air volumetric fraction: (Three different velocities)
Gas/Liquid/Solid flow in mixers
Gas/Liquid/Solid flow in mixers• Water velocity:
Bubble columns: effect of the volume of flow injecting
• Objective: simulation to observe and study the relevantphenomena when injected air volume flow is changed.
• Bubble columns: Shaking / Mixing / Chemical reaction.
• Big importance and difussion of the chemical and processindustry.
• University of Salamanca collaboration:
• We published in collaboration an article comparingexperimental and CFD results. “M. Elena Díaz, Alfredo Iranzo, Daniel Cuadra, Rubén Barbero. "CFD Simulation of the Gas-Liquid Flow in a Laboratory Scale Bubble Column. Influence of Bubble Size Distributions and Non Drag Forces". Chemical Engineering Journal(2007). ”
Case 02
Postprocessed results• Results (Q2= 96 cm3/s):
• Results:
• POP (Plume Oscillation Period)
• Gas Hold-Up (air fraction at the column)
Q[cm^3 s^-1]Hold-Up
CFDHold-Up
Exp Err [%]POP CFD
[s]POP Exp
[s] Err [%]
19 0.0067 0.0069 3.50 10.65 11.38 6.37
96 0.0294 0.0263 -11.79 4.90 4.30 -13.95
170 0.0480 0.0410 -17.11 3.00 2.80 -7.14
Fluidized bed simulation:
Temperature effect on different sands
Case 03
• Objective: Study the relevant phenomena when the sand ischanged from sand I to sand II.
• Fluidized be in combustion of waste products:
• Right starting up for sand I.
• Vitrification of the sand in the injectors area for sand II.
Geometry
• Application• Simplifying geometry to 2D
Wall
Simmetry Air injectors at 25 ºC
0,0167 kg/s
H = 0.45 m
• Operating temperature: 800 ºC.
Postprocessed results
• Results: Fluidization
Colours bar is showingthe volumetric fractionof the sand.
Time evolution of fluidization bed
ScrubberCase 04
• Objective: Study the relevant phenomena when the liquid injection volume of flow is changed.
• Scrubbers:
• Big importance for the chemical and process industry. Environment.
• Gas treatment: eliminate noxious fumes for the enviroment (SOx from combustion gases and others).
Geometry
Typical model• Height = 6.5 m
• Diametre = 2 m
• Injectores stage = 2
Gas outlet
Filter (demister)
Liquid inlet
Gas inlet
Liquid outlet (slurry)
Postprocessed results
• Results (Q1= 0,015 kg/s)
Droplet paths
Volumetric fractions
Postprocessed results
• Results (Q1= 0,015 kg/s)
Droplet residencetimes
Gas residence time
Results postprocessed
• Improving design/starting up (Q1= 0,015 kg/s):
• Flow homogeneization baffles:
• Avoid dead zones.
• Avoid preffered ways.
• More number / better distribution of injectors:
• Bigger contact area gas/liquid.
Inlet OutletSO2.mf 0,001 0,00063H2O.mf 0,050 0,056
Temperature [ºC] 800 773
Conclussions
• Modelling a scrubber using CFD.
• Multiphase (Gas-liquid drops):
• Injectors.
• Filters / demisters.
• Heat and mass transfer:
• Warming and evaporation of water drops.
• SO2 absorption.
• Gas cooling.
Pollutants dispersion simulation:
• Toxic clouds.
• Risk of explosion evaluation.
Case 05
• Objective: Evaluation of the consequences of an hypothetic leak ofdangerous substances at a chemical industry.
• Pollutants dispersion:
• Big importance for the chemical or processes industry. Enviroment.
• Toxic clouds, risk explosion evaluation, vulnerability analysis.
Geometry
• Land: 3,6 km x 5,2 km.
Town
Chemical industry (leak)
Wind with velocity profile. 2 m/s at 10 m height.
Preprocess
• Simulation objectives:
• Evaluate ethane risk of explosion (minimum level toignite).
• Chlorine vulnerability analysis:• Probit (death probability).
• IDLH (Immediately Dangerous to Life or Health).
• TLV-STEL (Threshold Limit Value-Short Term ExposureLevel).
• Evaluate the starting up of the emergency plans:• EAEC (Emergency Airborne Exposure Concentration
Levels, EPA).
Results
• Results: ethane risk of explosion
• Inferior limit to ignite = 0,0375 [kg m^-3]
Risk of explosion if the cloud
finds the ignition source
Results
• Results:
Chlorine TLV-STELChlorine IDLH
Results
• Results: Vulnerability: death probability (PROBIT method)
Exposition time = 15 min.
Mixing and chemical reaction processes
Case 06
Introduction• Acid/base chemical reaction in a system:
Exit
Inlet 1, 371 kg/s, 285 K50 % base, 50 % water
Inlet 2, 317 kg/s, 315 K22 % acid, 78 % water
• Physical-chemical phenomena:
• Mix of two multicomponent flows.
• Turbulence.
• Chemical reaction: H2SO4 + 2 NaOH Na2SO4 + 2 H2O.
• Exotermal reaction: 460 kJ/kg.
• Heat transfer.
Results
• pH
pH outlet = 7.3
Average pH = 11.3
• Reaction Rate
Polythene polymerization reactors (PET)
Case 07
INTRODUCTION
• Low density Polythene Reactors (LDPE):
• Reactor de Mezcla en Continuo (CSTR).
• Tubulars.
INTRODUCTION• Polymerization reactions:
• Momentum model [1]
I: initiator
A: initiator´s radical
M: monomer
Rx: radical with arbitrary length
R: total radical = sum (Rx)
P: product
• It is included variables to represent thedistribution of the mollecular weight ofproducts.
• Viscosity of the medium as a temperature function and theconcentration de las especies
Kiparissides, C., et al., “Dynamical Simulation of Industrial Poly(vinyl chloride) Batch Suspension Polymerization Reactors,” Ind. Eng. Chem. Res., 36 (4), p. 1253 (1997).
INTRODUCTION
• Typical results (250 rpm, tank without baffle)
ANOTHER CASE STUDIES
• Analysis of the interaction between fluid dynamics and chemical reaction.
• Mixing processes optimization with differentphases: gas, liquid and solid (particles).
• Risk analysis for pollutants dispersion, toxiccloud, etc.
ANALISIS-DSC reduces the production costs in your companydue to an optimized design of the processes reducing thenumber of prototypes and redesigns.
ANALISIS-DSC helps the Commercial Department as a marketing tool showing your product in a more attractivemanner. It also helps to share the information among severaldepartments.
ANALISIS-DSC helps prevent and analyzed accidentes in yourfacilities with the help of technical reports or engineeringprojects.
ANALISIS-DSC increases the benefits of your company due tothe increment of efficiency in your productive processes usingour know-how..
SUMMARY
CONTACT
www.analisis-dsc.com, click on the top right part forthe English version.
+34 914614071 or +34 914284802
ANALISIS-DSCC/ Nuestra Señora de la Luz, 21 local Izq. 28025 Madrid (SPAIN)
If You are interested in a technical meeting or in getting more informationabout our products and services, do not hesitate to contact us.