1. Methanol Project
Design a plant to make methanol from synthesis gas to supply a future market in direct methanol fuel cells

2. Methanol Project Don Robinson
Documentation
What we want to do => Basic Data
Available Lab Facilities => Analysis & Planning
Questionnaire to be worked on this week => Basic Data
Methanol Project Don Robinson

3. Methanol Project Don Robinson
Who We Are
Limestone Engineering Consultants Ltd.
Contracted by a major petroleum company
Specific scenario (one of many): What does the client do if motor vehicle industry shifts to direct methanol fuel cells for environmental reasons
Methanol Project Don Robinson

4. Methanol from Natural Gas
Synthesis Gas: CH4 + H20 => CO + 3H2
Water Gas Shift: CO + H20 <=> CO2 + H2
Methanol from CO and CO2: CO + 2H2 <=> CH3OH CO2 + 3H2 <=> CH3OH + H2O
Methanol Project Don Robinson

5. Methanol Project Don Robinson
Our Task
Our client has developed a design for a synthesis gas process
We are to develop a design for a process to convert the synthesis gas to methanol
The design is to be for a semi-commercial demo unit, although it is hoped that this will eventually lead to a world scale plant
Methanol Project Don Robinson

6. Methanol Project Don Robinson
Chemistry
The earlier literature points out that methanol can be made from either CO or CO2
The latest thinking is that, with the commonly used catalytic systems, virtually all of the product comes from the CO2 reaction
CO goes via a rapid water gas shift
Methanol Project Don Robinson

7. Methanol Project Don Robinson
A Problem
Overall reaction is CH4 + H2O => CH3OH + H2
Conversion per pass is low (recycle required)
To avoid H2 buildup it is necessary to separate it from a CO/CO2/CH4 mixture
This is not easy to do
Methanol Project Don Robinson

8. Methanol Project Don Robinson
Our Solution
Add sufficient CO2 to the synthesis gas so that there is a stoichiometric ratio
That is, reaction to completion would result in zero amounts of CO, CO2, H2
Assume that CO2 is available from an ammonia plant or some similar source
Methanol Project Don Robinson

9. Methanol Project Don Robinson
Kinetics
Both reactions are reversible - methane to syngas - syngas plus added CO2 to methanol
We have determined experimentally values for rate and equilibrium constants
Side reactions generate ethanol and fusel oil (no detailed kinetics)
Methanol Project Don Robinson

10. Methanol Project Don Robinson
Overall Process
Recycle
Product
Reactor System
Recycle System
Separation Section
Feeds
Waste or
Reuse
Methanol Project Don Robinson

11. Methanol Project Don Robinson
Previous Attempt
A design for this process was developed last year
Although technically successful, the economics did not look good
We want to try again with a better reactor design
Methanol Project Don Robinson

12. Removing Heat of Reaction
Old design was 3 sets of: adiabatic packed bed reactor followed by heat exchanger
New design is a single cooled reactor, much like a shell and tube heat exchanger, with catalyst in the tubes and coolant in the shell
Methanol Project Don Robinson

13. Other Design Improvements
Convert most CO to CO2 before the main reactor (less heat to remove)
Do a better job of dealing with the impurities
Get kinetic data in lab
Reconfigure distillation train
Utilize what was learned last year
Methanol Project Don Robinson