社区化粪池污水能量转化估算与分析研究

Estimation and analysis of embodied energy conversion in community septic tank

以化粪池单元为研究对象,基于ADM1模型的反应过程,建立了社区化粪池污水能量转化核算模型(WeMax-STK模型),对污水能量在化粪池中的赋存、转化以及去向进行了分析,并评估了污水能量的回收潜力.结果表明,WeMax-STK模型整体可靠,模拟值与监测值的平均误差不超过24%,不确定性低于18%,模型准确率在70%以上.化粪池进水有机物转化为热能和内部微生物能量的比例约占进水总化学能量的17%,污水化学能的主要去向是转化为慢速降解基质的能量,化粪池内有机物转化为气态甲烷的能量仅占进水化学能总量的4%左右.污水热能的回收强度约4.6kWh/m3,热能回收潜力约为24%~25%,大约是污水化学能回收潜力的3~6倍.

Taking the septic tank as the research object,based on reaction processes of anaerobic digestion model No.1,this paper established the unit model for calculation of water-energy-emission nexus in urban complex system-community septic tank(WeMax-STK),and analyzed the occurrence,conversion as well as the destination of sewage embodied energy,and evaluated the recovery potential of energy.The research results showed that the We Max-STK model was generally reliable,the average error between the simulated value and the monitored value didn’t exceed 24%,the uncertainty was less than 18%,and the accuracy was more than 70%.The percentage of organic matters which conversed into thermal energy and internal microbial energy was about 17%of the total chemical energy in septic tank influent.Most sewage embodied chemical energy was transformed into slow degradation substrate,and the energy converted from organic matter into gaseous methane in the septic tank only accounts for about 4%of the total amount of chemical energy in the influent.The thermal energy recovery intensity was about 4.6k Wh/m~3,and the recovery potential was 24%to 25%,which was about 3 to 6 times that of chemical energy.