木质素制备航油工艺与能耗优化

The cyclic structure of lignin monomer makes it an effective precursor for the preparation of aromatic and naphthenic hydrocarbons in alternative aviation biofuel. Aspen Plus conducted a material and energy consumption analysis of various routes by comparing the features and material flow of lignin depolymerization-hydrotreating for the production of aromatic and naphthenic hydrocarbons, gasification for the production of hydrogen, and combustion for heat. The yield of aromatic hydrocarbons from lignin is 17.3%~20.7%; naphthenic hydrocarbons from lignin is 17.5%~23.7%; hydrogen from lignin is 35.519 g/kg lignin; and the heat from combustion is 22.942 MJ/kg lignin. In order to make full use of lignin, several integrated processes for biofuel production were designed with hydrogen supply from lignin gasification and heat supply from lignin combustion. By using energy analysis and optimization, the integrated process of pyrolysis-alkylation-hydrotreating for aromatic or naphthenic hydrocarbons produces a yield of 11.8% or 9.2%, with a heat load of 7.357 MJ/kg lignin or 7.687 MJ/kg lignin; for aromatic and naphthenic hydrocarbons (1∶1), the integrated process of lignin pyrolysis-alkylation-hydrotreating produces a yield of 10.3%, with a heat load of 7.538 MJ/kg lignin and hydrogen consumption of 0.27%. Although the process of lignin one-step hydrotreating for biofuel production is mild and simple, the reaction system still needs to be further improved for its significant energy consumption.