Life cycle assessment of biomass conversion to feedstock chemicals

The life-cycle assessment (LCA) methodology was applied to the comparative analysis of two processes for producing 1,4-butanediol. The first process is the conventional hydrocarbon feedstock-based approach, utilizing methane to produce formaldehyde, and acetylene with synthesis under conditions of heat and pressure. The second is a biomass-based feedstock approach where glucose derived from corn is fermented. When evaluated from the standpoint of consumable fuels consumption, the conventional process is more environmentally compatible because it relies more on direct energy consumption-combustion of fuels at the point of energy use-which is more efficient than utilizing electricity. However, from a total energy consumption standpoint, the alternative process is favored. On an environmental impact basis, the alternative process is favored by a significant margin. This fact is due in a large part to the utilization of the renewable starting material, corn. The LCI and LCIA can also be utilized to offer other insights. Both systems utilize electricity, but the alternative system more so; by switching from nonrenewable to renewable energy sources the environmental impact of the alternative system relative to the conventional system could be lowered even more. The alternative system utilizes much more petroleum-derived energy during the raw materials processing stage; a switch from conventional to alternative agriculture would also lower the environmental impact of the system.