生活垃圾填埋短期好氧预处理工艺优化研究

以模拟有机生活垃圾为底物,通过实验研究了通风和温度协同控制作用下,填埋短期好氧预处理过程垃圾VS、含水率和有机组分的代谢情况.结果表明,好氧预处理过程VS降解主要发生在反应前期(0~6d),占实验全过程降解量的68%~85%;同时垃圾含水量的15%~26%以渗滤液和气体的形式被去除,并且延长通风时间能够增加后者所占比例.反应前期堆体自发升温到高温状态(50~55℃)比控制堆体温度维持在中温状态(42~47℃)更利于碳水化合物的代谢,但对粗蛋白降解的影响不明显.而在中温状态下粗脂肪和木质纤维素的降解率更高.继续延长预处理时间至14d,不同通风和温度的组合对VS和水分总体去除差距不大.控制填埋好氧预处理周期在6d并尽量维持堆体温度在50~55℃,成本-效益较高.

Optimization of short-term aerobic pretreatment process for municipal solid waste landfilling

Synergetic effect of aeration and pile temperature on VS and water content removal and biochemical components degradation during short-term aerobic pretreatment process prior to municipal solid waste (MSW) landfilling were investigated. Simulated organic fraction of MSW (OFMSW) was used as substrate. The results showed that VS rapid degradation was obviously occurred in the initial stage (0~6d), accounting for 68%~85% of total VS degraded in the whole experimental period; simultaneously, approximate 15%~26% water was removed in the forms of leachate and vapor, and extending aeration time could evaporate more water. In the initial stage, the temperature of pile increased to thermophilic condition (50 to 55℃) by self-heating, which was more beneficial for carbohydrates degradation than the mesophilic condition (42 to 47℃) of the controlled pile, while was insignificant to crude protein degradation. Yet, crude fat and lignocellulose have higher degradation rate under mesophilic condition (42 to 47℃). As the pretreatment period extended to 14 days, different synergetic operations combined aeration and pile temperature exhibited minor difference on the removal of VS and moisture. This study showed that a 6 day aerobic process with the pile temperature between 50 to 55℃ was a cost-efficient pretreatment method prior to MSW landfilling.