应用复合碱式氯化铝对垃圾渗沥液进行预处理的研究

Study on pretreatment of landfill leachates using complex polyaluminum chloride coagulant

采用生物法处理垃圾渗沥液 ,其出水CODCr、色度和含盐量等指标往往大于排放标准。应用亚滤技术作深度处理 ,可有效地去除剩余的污染物质 ,使出水达标。但由于渗沥液中存在大量的胶体微粒 ,对亚滤管产生阻垢作用 ,从而堵塞住亚滤管微孔 ,增加动力消耗 ,影响处理效果。故采用一种新型高效的复合型无机高分子混凝剂———聚硫氯化铁铝 (PAFCS)用于亚滤装置的预处理。通过与碱式氯化铝 (PAC)混凝剂的对比研究表明 ,PAFCS表现出比PAC更好的除浊、脱色能力 ,可有效地去除掉垃圾渗沥液中的浊度、胶粒和部分CODCr,从而使亚滤装置发挥最大效能。结果表明 ,PAFCS的投加量在1 50— 2 0 0mg/L左右 ,pH值在 5左右 ,沉降时间为 40— 50min的条件下 ,混凝效果最佳 ,浊度去除率可达到 90 % ,CODCr去除率可达 40 %左右。

Using biological treatment , the content of COD Cr , color and salinity of landfill leachate are often larger than discharge standard.In this case, the landfill leachates can be purified effectively by the method of Sub-Filter(SF). However, because there are millions of colloidal particles and SS in the leachates, they can cause high fouling power on the tubes in the SF towers. So, we apply a new coagulant——PAFCS as pretreatment of SF. Compary with PAC, we find that PAFCS has a better turbidity and SS reducing and decolor ability. It also can reduce some of COD Cr . By this method, the SF can purifiy the leachates with flying colors. The result shows that, under the condition of the addition of PAFCS at about 150—200mg/L, pH about 5,setting time 40—50min,we can achieve the best outcome: the removal rates of turbidity and COD Cr were about 90% and 40% respectively.