污水厂剩余污泥好氧堆肥工艺参数的控制

Parameters Control of Aerobic Composting of Excess Activated Sludge from Wastewater Treatment Plant

对银川市污水处理厂产生的剩余污泥进行了好氧堆肥中试研究,重点考察了对污泥含水率、通风方式等参数的控制。结果表明,在剩余污泥的含水率为80%左右的条件下,采用自然晾晒3～5d的干燥方式即可基本达到进料污泥的最佳含水率范围(50%～60%),节省了掺混污泥调理剂的费用;最佳的堆肥通风方式为间断强制通风;污泥经初次、二次发酵后,对蛔虫卵的杀灭率达到100%,总大肠菌群数≤100个/kg(降低了约5～7个数量级);堆肥成品呈疏松的团粒结构,无恶臭气味,无蚊蝇孳生。

The pilot study on aerobic composting of excess activated sludge from Yinchuan Wastewater Treatment Plant was carried out. The control of parameters such as water content of sludge, ventilation mode and so on was investigated. The results show that when the water content of excess activated sludge is about 80%, the optimal water content of feed sludge （50% to 60% ） can be achieved by sun drying the excess activated sludge for 3 to 5 d, which saves the cost of mixing sludge conditioner. The optimal ventilation mode is intermittent forced ventilation. After the first and second fermentation, the killing rate of ascaris eggs reaches 100%, and the total coliform count is equal to or less than 100 CFU/kg, which is decreased by 5 to 7 orders of magnitude. The composting product has loose granular structure, no odor, no mosquito and flies breeding ground.