农林废弃物气化合成混合醇生命周期环境影响分析

生物质热化学气化合成混合醇技术具有工艺相对简单、产物的能源化工应用广泛等优点，为准确评价该技术的资源能源消耗、辨析合成燃料的环境性能，基于生命周期分析框架和ReCiPe2016中点评价方法，对农林废弃玉米秸秆和木屑经气化、催化合成混合醇工艺的清单和9种环境影响类型开展分析和比较。结果表明：农林业阶段均为环境影响的主要阶段，秸秆混合醇生命周期影响高于木屑混合醇。前者的臭氧层耗竭潜值、海洋和淡水富营养化潜值、全球变暖潜值均为木屑混合醇相应结果的9倍以上。废弃物原料高碳含量和高混合醇收率有利于降低资源消耗和环境影响。与石化汽油相比，秸秆和木屑混合醇的全球变暖和化石能源消耗潜值均降低40%以上。

Life cycle environmental impact assessment of mixed alcohol via gasification of agricultural and forestry residues and catalytic synthesis

The bio-mixed alcohol production process via biomass gasification and the followed catalytic conversion of syngas has the advantages of simple procedure, high yield and diverse utilization of alcohols as bioenergy or biochemicals. To ascertain its environmental performance such as resource consumption and emissions, the analysis and comparison of the impact was carried out for mixed alcohols from agricultural and forestry residues of corn stalk and wood chips via gasification and catalytic synthesis processes, following life cycle assessment frame (LCA) and midpoint impact method of ReCiPe2016. 9 environmental impact categories were considered such as global warming potential (GWP) and fossil resource scarcity potential (FDP). The main environmental impact for both alcohol systems was derived from agricultural and forestry stages. The potential environmental impact values of alcohols from corn stalk were higher than those from wood chips. And the ratios of ozone depletion potential (ODP), marine and freshwater eutrophication potential (MEP and FEP) and global warming potential (GWP) of the systems between mixed alcohol production from corn stalk and wood chips were above 9. The relatively high carbon content and high alcohol yield will benefit the decrease of resource consumption and environmental impact. Compared with petrochemical gasoline, the global warming and fossil energy consumption potential of the mixed alcohol of straw and wood chips are reduced by more than 40%.