Comparative techno-economic analysis of biofuel production through gasification, thermal liquefaction and pyrolysis of sugarcane bagasse

Abstract Techno-economic models for three plants in Queensland, Australia using thermochemical conversion of 10 tonnes per hour of sugarcane bagasse to liquid crude biofuels were developed. Thermochemical conversion was chosen to maximise yield from second-generation feedstock. The process models highlighted the differences in mass and energy flows of each process. Factory models were generated reflecting current methods in heat and material recovery. Liquefaction generated the highest amount of product per kg feed, followed by pyrolysis and gasification. Key parameters affecting plant economics were also highlighted. Based on net present values, the profitability was ranked as follows: pyrolysis > liquefaction > gasification. The plants were all sensitive to product price, thermochemical conversion ratio and refining conversion ratio, thereby affecting profitability the most. Conversion ratios sharply affect the minimum selling price of products, but attenuated by high product volumes. Varying tax rates and capital costs do not affect the minimum selling price as much as conversion ratios, therefore, incentives around improving conversion rates and increasing product volume are recommended.