城市生活垃圾可生物降解组分的动态水解研究

The study on dynamic hydrolysis of organic fraction of municipal solid waste

摘要:

通过96h无置换动态水解批式实验和不同缓冲液置换频率动态水解批式实验，研究破碎预处理、翻转、甲烷化出水和不同时间间隔置换操作对于城市生活垃圾可生物降解组分（OFMSW）厌氧消化水解过程的影响。结果表明：翻转可使OFMSW的动态水解效率最高达到42.7%（未破碎甲烷化出水缓冲液工况），而不翻转时仅有22.3%；与蒸馏水相比，未破碎预处理工况下，甲烷化出水可使OFMSW的水解效率提高40.6%；但破碎预处理之后，仅提高了3.6%，说明对OFMSW进行破碎预处理不会显著提高水解效率，反而增加了破碎能耗；缓冲液置换操作一定程度上解除了高浓度有机酸的产物抑制；不同置换频率工况相比，虽然每24 h和每48 h置换的工况比每12 h置换的工况所得到的OFMSW减重率分别高出11.5%和40.7%，但能耗相应增加了100%和300%，因此，缓冲液置换频率以12h为最佳。

Abstract:

Batch experiments of dynamic hydrolysis at different hydrolysate replacement frequencies in 96h were conducted to evaluate the effects on anaerobic hydrolysis of organic fraction of municipal solid waste (OFMSW) caused by homogenization pretreatment, overturn, methanogenic effluent and hydrolysate replacement frequency (12 h, 24 h, 48 h, 96 h ). It showed that the operation of overturn mixing improved the hydrolysis efficiency of OFMSW by 42.7% at the most which happened in the methanogenic-buffered scenario without homogenization, and the hydrolysis efficiency in the scenario without the operation of overturn mixing can only be 22.3%. Comparing with the distilled water, using methanogenic effluent as buffer increased the hydrolysis rate of un-homogenized OFMSW by 40.6%. However, the increment was only 3.6% in the hydrolysis of homogenized OFMSW, which indicated that the homogenization had not significantly improved the hydrolysis efficiency, but increased the energy consumption. Hydrolysate replacement to some extent eliminated the inhibition of organic acid. The increments of weight loss by 11.4% and 40.7% were accomplished in the scenarios with hydrolysate replacement frequencies of 24 h·run-1 and 48 h·run-1, comparing with that of 12 h·run-1. However, the energy consumptions increased by 100% and 300%, respectively, suggesting that the hydrolysate replacement frequency of 12 h·run-1 is optimal.