(644d) Life-Cycle Assessment of Lanzatech Waste Gas Conversion to Ethanol and Co-Products

Shonnard, D. R., Michigan Technological University
Palou-Rivera, I., Argonne National Laboratory

A novel method of ethanol production has been developed by LanzaTech, relying on readily abundant carbon monoxide-containing gas feedstocks. Feedstock gases may be industrial waste gases (e.g., steel mill exhaust gas) or may be produced through gasification of biomass feedstocks. In this presentation we will give an overview of the LanzaTech process and summarize initial findings related to the environmental footprint of ethanol production in this manner. Greenhouse gas emissions and fossil energy demand are the key impacts discussed, but water use is also compared to other ethanol production routes. The importance of allocation method used to attribute environmental burdens between ethanol and chemical co-products will be highlighted, along with key assumptions concerning potential alternative use of feedstock gases. Bio-based feedstock results will be summarized and comapred to waste gas feedstocks, using common bio-based feedstocks and current information on gasification of biomass. Important considerations from the initial life cycle assessment of potential LanzaTech operating scenarios will be used to provide guidance about the proper role of this technology in the future alternative fuels marketplace.