渗滤液的同质与异质回灌技术

Cross and homogenous re-circulation of leachate

根据承受回灌封场单元的稳定化程度、渗滤液与回灌载体的同质或异质关系,提出了渗滤液在其母体垃圾体中回灌的同质回灌概念和渗滤液在非母体垃圾中回灌的异质回灌概念.在异质回灌中,渗滤液可以引到稳定化程度较高的非母体填埋单元回灌,从而明显提高渗滤液中污染物的去除效果.同质回灌中,渗滤液与回灌垃圾载体性质相似,处理效果较差,其回灌意义基本上是自然蒸发减量化.

In this paper, the leachate re-circulation is categorized into two types, i. e. , homogenous leachate re-circulation and cross re-circulation. The former type of leachate re-circulation means that the leaehate is re-circulated within the refuse layers that generated the leaehate, regardless of the stability of the refuse involved. The latter means that the leaehate generated in one refuse layer is re-circulated in another independent refuse layer, with higher stability and longer placement time in the landfill. Two types of re-circulation may lead to different treatment effieieneies of the pollutants removals because of the disparity of the refuse layers＂ stabilization extent, besides the evaporation effects. In general, the pollutant removal capability of the cross recirculation process is over that of homogenous re-circulation, as the more stable refuse can act as an effective biofiltration reactor which has a high biodegradability to the pollutants present in the leachate. For the homogenous re-circulation, the leaehate re-circulated and the refuse layers subjected to re-circulation has similar characteristics and the refuse layer has been found to have much less ability to degrade the pollutants.