垃圾焚烧厂渗滤液软化耦合膜处理工艺中试研究

Pilot Scale Study on the Leachate Treatment Process of Chemical Softening Coupling Membrane

生活垃圾焚烧厂渗滤液处理常采用“厌氧+生化+深度膜+浓液再浓缩”工艺,该工艺存在流程偏长,设备操作复杂,设备投资、运行成本偏高等问题。本研究采用“软化+超滤UF+反渗透RO”膜处理新工艺替代常规的“深度膜+浓液再浓缩”工艺,对某垃圾焚烧厂渗滤液处理系统MBR出水进行了中试试验。水质分析表明,该新工艺流程较短,操作便捷,系统整体回收率为80%时,MBR出水中的总硬度(以碳酸钙计)、COD和Cl^(-)的去除率分别达到99.4%、98.3%和95.5%,达到了常规处理工艺的处理效果;经济性分析表明,新工艺在运行电耗及设备折旧方面较原工艺节省约46.7%。

The leachate treatment system of domestic waste incineration plants generally adopts the“anaerobic+biochemical+membrane+concentrated liquid re-concentration”process. There were some problems for this process such as long treatment process,complicated equipment operations,high equipment investment,and high operating costs. A new process of“softening +ultrafiltration(UF)+reverse osmosis(RO)”membrane treatment was used to replace the conventional“membrane + concentrated liquid re-concentration”process,and a pilot test of MBR effluent from a leachate treatment system in a incineration plant was carried out. The results showed that the new process was simple and easy to operate. When the overall recovery rate was 80%,the total hardness(calculated as CaCO3),COD and Cl^(-)removal rate of the MBR effluent reached 99.4%,98.3% and 95.5%,respectively,achieved the treatment effect of the conventional process. And economic analysis showed that the new process saved about 46.7% in operating power consumption and equipment depreciation compared with the original process.