Process Design and Simulation of Propylene and Methanol Production through Direct and Indirect Biomass Gasification

Abstract

As a result of increasing environmental concerns and the depletion of petroleum resources, the search for renewable alternatives is an important global topic. Methanol produced from biomass could be an important intermediate for liquid transportation fuels and value-added chemicals. In this work, the production of methanol and propylene is investigated via process simulation in Aspen Plus. Two gasification routes, namely, direct gasification and indirect gasification, are used for syngas production. The tar produced in the process is converted via catalytic steam reforming. After cleanup and treatment, the syngas is converted to methanol which will be further converted to high value olefins such as ethylene, propylene and butene via the methanol to propylene (MTP) processes. For a given feedstock type and supply/availability, we compare the economics of different conversion routes. A discounted cash flow with 10% of internet rate of return along 20 years of operation is done to calculate the minimum selling price of propylene required which is used as the main indicator of which route is more economic attractive.