Conceptual Design and Techno- Economic Analysis of Biomass to Liquid Processes

Abstract

There is a need for diversifying energy resources for better energy security. Moreover, diversification is critical in reducing the dependency on fossil fuels and subsequent carbon emissions. The thesis outlines Biomass to liquid technology (BtL) based on the gasification of biomass and fuel synthesis using the Fischer-Tropsch (FT) synthesis process. The BtL technology utilizes waste biomass and forest residues to produce bio-syncrude which on upgrading has similar physical and chemical characteristics as conventional fuels. The thesis explores conventional BtL technology and outlines the various process alternatives to address the low process efficiencies of existing BtL processes. For this purpose, the research work employs modeling and optimization of FT synthesis to identify the optimal process window for maximizing net production and staging strategies. Further, the results are incorporated to propose novel BtL processes where external electrical energy in solid-oxide electrolytic cells (SOECs) is added to increase the overall carbon efficiency of the BtL process. The results show that cheaper SOEC technology or utilization of waste electricity will increase the viability of BtL technology and can replace aviation fuels with BtL fuels.