Overview of Methanol Model

We will start with Start.hsc and use it to do equipment design and cost estimation

Start.hsc This is a simplified model to

represent the SynGas process The units you see are not intended

to represent the actual pieces of equipment in the plant

It’s purpose is to do the heat and mass balances necessary to create a feed stream for the methanol plant

Idea from Last Year Heat removal in methanol reactors

was a big problem Both CO=>CO2 and methanol

reactions are exothermic Reduce heat load in methanol

section by converting as much of the CO as possible in the syngas section and then cooling the stream

Feed and Syngas Reactor

Water Gas Shift Reactors

Structure of Methanol Process

ReactionSection

SeparationSection

RecycleSectionCO2

*

Syngas

Recycle

Purge

MeOH

Water

Lights

Heavies

* 126.667 kmol/hr

Reaction Section Reactor: Like a S&T heat

exchanger Multi tubed Packed with catalyst Cooled with water in shell Uses HYSYS Plug Flow Reactor Unit

Feed and coolant temperature are important

Defining Reactions

Check Rxn Phase & Rate Units

Kinetic Constants

Kinetic Constants Syngas, water gas, methanol

values are in Start.hsc For the impurities use:

Ethanol: 1E24, 2E5 Acetone: 1E28, 2E5 Fusel Oil: 1E25, 2E5

Plug Flow Reactor Design Read Process in Basic Data very

carefully before you strat work on the reactor

It contains much vital information on techniques and selection of parameters

HYSYS Plug Flow Reactor Unit

Develop Reactor Design Guess at T,P,Conc. of recycle stream Optimize four parameters

T of feed and coolant (max MeOH) Flow of coolant (max MeOH) Number of tubes (95% to equilibrium)

Compare actual recycle rate with assumed value

If difference > 1%, start again

Close the Loop

Recycle Section Cool reactor product to condense

methanol and water Collect liquid and send to

Separation Purge some vapour to prevent

buildup of light components Compress the rest of the vapour

and send it back to the reactor

Questions to Think About At what temperature and pressure

should the flasher operate? Why?

Distillation Train Purpose

Purify product Recover light gases and heavy

impurities for fuel Recover water for reuse

See my feedback for the Initial Review for suggestions on the designs

Step 1: Water Column

From RecycleSection

Water for Reuse

Dry Organics toLights Column

V

L

Step 2: Lights Column

Dry Organics

Alcohols

Residual Gases and Acetone

Step 3: Product Column

Alcohols

Methanol Product

Ethanol & Fusel Oil

Report for Modeling Assignment

In your group folder set up folder “Model”

Put in it by 2:15 Wed Oct 15: HYSYS model - .hsc file Summary of our progress with the

task Anything else you want me to

consider

Summary of Progress An engineer from our client is

coming to review our progress Our supervisor has asked us to

prepare a summary of: What we have accomplished What we learned in working out the

design Any issues of concern that have arisen

Summary continued Our visitor has 15 minutes to read

and digest the report before discussing it with us

Both the analysis assignment (mass balance and catalyst characterization) and the building of the model should be covered

This probably means 3 to 6 pages