Thermochemical biomass to liquid (BTL) process: Bench-scale experimental results and projected process economics of a commercial scale process.

Abstract: In this paper, we examine the technological feasibility and economic viability of producing liquid fuels from biomass via thermo-chemical route. We initially present laboratory scale production results for synthesizing liquid fuels using syngas derived from biomass. The experiments showed that excellent yield of middle distillate products can be obtained from the bio-derived syngas, but it required supplementing the syngas with hydrogen due to low H2/CO ratio. The results from bench-scale liquefaction unit served as the basis for subsequent modeling and simulation of a biomass to liquid production facility which in turn is used for a preliminary economic analysis of a commercial scale facility using this technology. Two different technologies are compared; one using biomass as the sole feedstock (BTL), while the other augmented biomass derived syngas with hydrogen using the reforming process (BGTL). The idea of co-processing was suggested due to (i) hydrogen deficiency in the biomass feedstock, and, (ii) lower cost of natural gas which is rich in hydrogen. The basis for the design was 2000 metric tons of dry biomass fed per day. We did not include CO2 capture and storage in this study. However, when co-processing was employed, there was significant reduction in CO2 emissions and carbon capture from the biomass increased. A conceptual process capable of 100% feedstock carbon capture is also presented. The breakeven cost of oil (BECOP) was estimated to be $124/bbl for the BTL plant versus $95/bbl for a natural gas assisted BGTL plant using current market prices for raw material and capital equipment. With the increased availability, and falling prices of natural gas, augmentation with natural gas can provide a bridge solution in short term for an economical biomass to liquid fuel technology. [Copyright &y& Elsevier]