高固体条件下黑水添加对厨余垃圾厌氧发酵的影响

Effect of blackwater addition on anaerobic digestion of kitchen waste under high solid condition

为探究高固体条件下黑水添加对厨余垃圾厌氧发酵性能的影响,设置了不同黑水添加比例以及不同接种比的发酵实验。结果表明,实验初期各组均出现了快速酸化,调节pH至7.3~7.5并添加缓冲剂后,产甲烷过程逐步恢复正常;添加了黑水的混合发酵实验组的累计甲烷产量相比厨余垃圾单独发酵实验组提升不大,而黑水的添加比例较高时,由于氨抑制作用,造成产甲烷量下降了46.7%;接种比由1下降至0.5时,混合比为3∶1和厨余垃圾单独发酵的实验组累计甲烷产量分别下降了73.2%和38.3%,平均甲烷含量分别下降了47.7%和13.0%。说明高固体、低接种比条件下,加入黑水不能有效改善厨余垃圾的厌氧发酵反应。该研究结果可为高负荷条件下厨余垃圾与黑水2种高浓度家庭有机废物流的资源化处理提供理论参考。

In order to explore the effect of blackwater addition on the anaerobic digestion performance of kitchen waste under high solid conditions,three groups of mixed raw feeding material digestion experiments with different blackwater addition ratios were set up.The results showed that rapid acidification occurred in each group at the initial stage of the experiment.After adjusting the pH to 7.3~7.5 and adding buffer agent,the anaerobic digestion process gradually returned to normal.The cumulative methane production of the digestion experiment group with blackwater addition did not increase significantly compared with the single digestion experiment group of kitchen waste,while the methane production decreased by 46.7% when the addition ratio of blackwater was higher due to ammonia inhibition.When the inoculation ratio decreased from 1 to 0.5,the cumulative methane production decreased by 73.2% and 38.3% in the experimental group with a mixing ratio of3:1 and kitchen waste alone,respectively,and the average methane content decreased by 47.7% and 13.0%,respectively.It was explained that under the conditions of high solids and low inoculation ratio,blackwater could not improve digestion performance for kitchen waste effectively.The results of this study can provide a theoretical reference for the resource treatment of two high-concentration household organic waste streams,kitchen waste and black water,under high load conditions.