应用复合混凝剂对垃圾渗沥液生化出水深度处理的研究

采用生物法处理垃圾渗沥液,其出水COD_(cr)、色度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COD_(cr),从而使亚滤装置发挥最大效能。结果表明,PAFCS的投加量在150～200mg/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％,COD_(cr)去除率可达40％左右。

Advanced Treatment of Landfill Leachates throughBiological Processes by using Complex Coagulant

Using biological treatment , the content of COD_(Cr), color of landfill leachate are often larger than discharge standard.In this case, the landfill leachates can be purified effectively by the method of Sublime Micrometre Filtration (SMF). However, because there are millions of colloidal particles and SS in the leachates, they can cause high fouling power on the tubes in the SMF towers. So, we apply a new coagulant--PAFCS as pretreatment of SMF. Compared 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 SMF can purified the leachates with flying colors. The result shows that when the addition of PAFCS was about 150 ~ 200 mg/L, pH was about 5, setting time 40 ~ 50 min, we can achieve the best efficiency: the removal rates of turbidity and COD_(Cr) were, respectively, about 90% and 40% .