基于[火用]效率的玉米秸秆厌氧发酵单产和联产氢烷性能分析

Performance analysis of anaer obic fermentation of corn stover for mono-and co-production of biohydrogen and methane based on the exergy efficiency

玉米秸秆厌氧发酵产氢、产甲烷,联产氢烷是秸秆能源化利用的3种重要的生化转化模式。为了筛选出玉米秸秆高效的生化转化模式,在玉米秸秆基质浓度分别为20,30,40,50,60 g/L的条件下进行了光发酵产氢、厌氧发酵产甲烷和光发酵产氢-厌氧发酵产甲烷两阶段联产氢烷的试验,从热力学[火用]效率和生态[火用]效率的角度对玉米秸秆单产或联产氢气和甲烷的性能进行了分析和评价。研究结果表明,光发酵产氢时,底物浓度为40 g/L的累积产氢量和累积收益[火用]最大,分别为323.67 mL和3.41 kJ,最大热力学[火用]效率为1.58%。厌氧发酵产甲烷时,底物浓度为60 g/L的累积产甲烷量和累积收益[火用]最大,分别为1546.46 mL和57.38 kJ,最大热力学[火用]效率为31.01%。氢烷联产时,底物浓度为60 g/L的氢气和甲烷联产的累积产甲烷量和累积收益[火用]最大,分别为1554..83 mL和60.83 kJ,最大热力学[火用]效率为22.20%。3种模式相比,玉米秸秆厌氧发酵单产甲烷转化具有最高的[火用]效率,且热力学[火用]效率和生态[火用]效率的评价结果是一致的。

Anaerobic fermentation of corn stover for hydrogen production,methane production,and co-production of biohydrogen and methane co-production are three important biochemical conversion modes.In order to screen out efficient bioconversion modes of corn stover,a series of experiments on photosynthetic hydrogen production,anaerobic methanogenesis and two-stage combined hydrogen production from photosynthetic hydrogen production-anaerobic methanogenesis were conducted at different corn stover substrate concentrations(20 g/L,30 g/L,40 g/L,50 g/L and 60 g/L)to evaluate the performance of corn stover in terms of thermodynamic and ecological efficiency.The results showed that for photosynthetic hydrogen production,the cumulative hydrogen production and cumulative yield of the substrate at a concentration of 40 g/L were the largest,at 323.67 m L and 3.41 kJ,respectively.The maximum thermodynamic efficiency was 1.58%.For methane production in anaerobic fermentation,the cumulative methane production and the cumulative heat gain at a substrate concentration of 60 g/L were 1546.46 m L and 57.38 kJ,respectively,with a maximum thermodynamic efficiency of 31.01%.In the case of hydrogen and methane co-production,the maximum value of cumulative methane production and the cumulative effective exergy of hydrogen and methane co-production were 1554.83 m L and 60.83 kJ,respectively,at the substrate concentration of 60 g/L,and the maximum thermodynamic efficiency was 22.20%.It could be found that the anaerobic fermentation of corn stover for mono-production of methane conversion had the highest efficiency of the co-production for the three diffierent fermentation process and the evaluation results of thermodynamic exergy efficiency were perfectly consistent with that of ecological exergy efficiency.