Thermo-economic Evaluation of the Thermochemical Production of Liquid Fuels from Biomass

Different technological alternatives for the thermochemical production of liquid fuels from lignocellulosic biomass are systematically analyzed and optimized based on thermo-environomic models. The competitiveness of the production of Fischer-Tropsch fuel (FT), methanol (MeOH) and dimethyl ether (DME) is compared with regard to energetic, economic and environmental considerations, and the optimal process configuration and operating conditions are identified. For the conceptual process design a consistent methodology using simultaneously process integration techniques, life cycle assessment (LCA) and a multi-objective optimization strategy is applied. In particular, the influence of the process integration on the overall process efficiency is investigated by studying several possibilities to satisfy the minimum energy requirements, to recover and valorize at most the available heat, and by studying the effect of the operating conditions. The most promising options for the polygeneration of fuel, power and heat will be identified based on multiple criteria. The performance for the different process steps and some exemplary technology scenarios of integrated plants are computed, and overall energy efficiencies in the range of 50-60% are assessed.