Maximum Single Train Ethylene Capacity
AIChE Spring Meeting and Global Congress on Process Safety
2017
2017 Spring Meeting and 13th Global Congress on Process Safety
The 29th Ethylene Producers' Conference
Ethylene Plant Capacity Constraints
Wednesday, March 29, 2017 - 4:30pm to 4:55pm
The technology options available to convert CO2 into higher value fuels and chemicals are not commercially well established. Developing commercially viable technologies to convert CO2 into high value products will improve the project economics of renewable and non-renewable carbon-based energy production. Such technologies can potentially create additional revenue streams with significant reduction in the net CO2 emissions. A well-known pathway for CO2 utilization is reforming of CH4 in presence of steam and CO2 (bi-reforming of CH4) for syngas (CO+H2) production. The syngas can then be used as a raw material for synthesis of fuels and chemicals, including methanol. The specific reactant stoichiometric ratio of CH4/steam/CO2 of 3/2/1 creates the syngas ratio of 2 which is critical for methanol synthesis. In this context, an Aspen plus process simulation model for bi-reforming reaction system coupled with the methanol synthesis reactor system is developed. The model considers a range of operating conditions and is used to optimize the integrated process. Under optimum operating conditions, the overall process thermal efficiency is 65%. The results from process simulation are used to conduct a Life Cycle Analysis (LCA) of the proposed pathway. Net GHG emissions from conventional steam methane reforming based methanol is about 497 kilograms of CO2e/tonne of methanol whereas the GHG emissions from the proposed bi-reforming based process is about 203 kilograms of CO2e/tonne of methanol produced on an LHV basis. The proposed technology can reduce about a million tonnes of CO2 equivalent GHGs per year in a 10,000 tonne methanol/day plant.