MODELING & SIMULATIONIN MINERAL PROCESSING

USING MODSIMTM SIMULATOR

-SM Shashidhar

USER-FRIENDLY FLOWSHEET EDITOR

Simulation starts with the definition of the flowsheet which is drawn initially on the monitor using a specialized graphics editor.The graphic editor has an extensive array of icons representing all the mineral processing unit operations encountered in practice.The editor also allows for quick modification of the flowsheet structure and replacement of existing units. 

An ore dressing plant simulator is a set of computer programs that provides a detailed numerical description of the operation of an ore dressing plant.

The simulator must be provided with an accurate description of the ore that is to be processed, a description of the flowsheet that defines the process and an accurate description of the operating behavior of each unit operation that is included in the flowsheet. The simulator uses these ingredients to provide a description of the operating plant.

ORE DRESSING PLANT SIMULATOR

DATA SPECIFICATION Data required to simulate

processing plants describe the characteristics of the material treated, the production rates targeted, and the details of the unit operations included in the flowsheet. The processing units are described by their physical characteristics and the parameters of the mathematical models that describe the operation of the physical equipment.

ModsimTM

Modsim is a versatile simulator for ore dressing plants. It simulates the behavior of many unit operations as they are situated in the flowsheet using quantitative models that determine how each unit will transform and/or partition its feed. The user must define the quantity and nature of the feed to the plant and the precise nature of every stream in the plant is calculated thereby establishing an exact material balance.

POPULATION BALANCE METHOD

MODSIM™ is based on the population balance method and is therefore capable of accounting accurately for variations in particle size and mineral liberation characteristics together with other critical properties such as density, mineralogical texture, elemental composition, magnetic susceptibility, energy content, etc. Data structures incorporate mineral and coal processing flowsheets. 

MODELS A wide array of models for the unit

operations is supplied. In most cases alternative models are available so that the user can investigate the differences between various models of the same unit.Most of the significant models available from the scientific literature are included. Each model comes with a set of realistic default parameters.User-specified models for any unit can be incorporated easily. Model selection is fully interactive so models can be changed with a simple mouse click. 

DATA OUTPUT Graphical, tabular and text

outputs display simulation results quickly and clearly. All output can be copied and pasted on most word processors for convenient and effective report production.Graphics can be exported as Encapsulated PostScript (.EPS) or Windows Metafile (.WMF). 

INTEGRATED FLOWSHEETS

crushing (jaw, giratory and cone crushers, high pressure rolls)

grinding (AG, SAG, Rod and Ball mills) classification (screens and hydrocyclone

s) flotation gravity separation (jigs, tables, cones,

sluices, dense medium vessels and cyclones, water only cyclones)

magnetic separation (dry and wet drum separators and wet high intensity separators)

solid liquid separation (thickeners, dewatering screens and filters).

FEATURES Is affordable, fully interactive and

user-friendly. Represents over 15 years of R&D

validated by numerous industrial applications.

Is designed for convenient and intuitive operation for ease of learning: basic user proficiency is achieved in less than one hour.

Requires no special training in computer modeling or simulation.

Allows easy incorporation of new models using the Development Kit supplied.

Provides a comprehensive user manual and on-line help. Manuals include complete description of the mathematical modeling methods and gives details of all the models used.

Offers several models for most unit operations, including the most recent and significant found in the scientific literature. Each model comes with a set of default parameters.

Automatically calculates recycle streams including regrinding.

Allows the user to select various system units: S.I., British, per hour, per day, etc.

Provides an unlimited number of units and streams per flowsheet.

BENEFITS MODSIM™ powerful and versatile capabilities make it the

perfect computer simulation tool for quarry operators, coal processors, base metal and industrial mineral producers, consultants and engineering firms in the mineral processing field.

MODSIM™ is a very cost effective solution for circuit design and optimization.

Mineral liberation simulation allows you to further optimize your separation processes by characterizing how each grade class and, ultimately, liberated minerals will be affected.

OVERALL PERFORMANCE OF THE PLANT

Ore dressing plants are collections of unit operations connected by process flow streams that transmit material from one unit to the next. The flow of materials is directed by the flowsheet structure. Each unit operation processes its own feed materials and will separate it or transform it in accordance with the specific objective of the unit. The behavior of the plant as a whole depends on the operating

characteristics of each of the unit operations as well as on the nature of the material that is processed in the plant. A simulator reduces the actual plant operations, as defined by the flowsheet structure and the behavior of the units, to a sequence of logical mathematical functions. The simulator can then mimic the real plant performance.

DESIGN STUDIES Help the design engineer to find the best flowsheet. Ensure that design specifications will be met under all required operating

conditions. Choose the most suitable unit operations to be included in the plant. Size

the units correctly and so eliminate wasteful over-design and avoid the catastrophe of under-design.

Optimize the plant operation by achieving best economic combinations of grade and recovery.

Identify potential production bottlenecks. Provide comparative assessment of competing manufacturers’ equipment. Define the performance guarantees that should be met by suppliers. Find out what will happen if performance guarantees are not met.

OPERATING PLANT PERFORMANCE A good simulator can be used to assist in the operation of a

running plant in ways such as the following: Optimum performance of the plant can be approached. The plant

can be tuned to suit variations in feed quality and flowrate. Plant bottlenecks can be found and appropriate steps taken to

eliminate them. Performance changes can be investigated by asking ‘what if’

questions. Operations that are not properly understood can be identified and

appropriate research effort undertaken to remedy such a situation.

1. RP King: Modeling and Simulation of Mineral Processing Systems ISBN: 978-0-08-051184-9

2. http://www.mineraltech.com/MODSIM/3. htTP://www.utah.edu

REFERENCES AND THANKS

THANKS