摘要
经循环回灌后的渗滤液出水含有大量的腐殖质,其生物降解性差、氨氮含量高,具有类似长填龄填埋层渗滤液的水质特征。用混凝法处理渗滤液循环回灌出水,通过混凝pH、混凝剂种类及其投加量实验,确定了最佳混凝条件;并通过分析混凝处理前后渗滤液循环回灌出水的分子量变化和从出水中分离出的腐殖酸(HA)、富里酸(FA)和Hydrophilic(HyI)三种组分的变化,讨论了混凝法对渗滤液循环回灌出水去除效率不高的原因。研究表明,聚合硫酸铁(PFS)在pH=5、投药量为0.22g/L(以Fe2O3计)的条件下的混凝效果最佳,其对渗滤液循环回灌出水的COD去除率达58.1%。混凝剂对渗滤液循环回灌出水中的HA、FA和HyI组分的去除效果依次为:HA>FA>HyI。
The recirculated leachate has the water quality characteristics similar as the old landfill leachate: large amounts of humic substances, low biodegradation and high NH_3-N concentration. The optimum coagulation conditions for the COD removal of recirculated leachate are determined through the experiment of pH, the kind of coagulant and its dosage. The causes of low removal efficiency are discussed by the change of the molecular weight and the change of the isolated fractions of the recirculated leachate through coagulation. The results show that 58.1% removal of COD can be realized by the addition of 0.22 g/L PFS at pH 5. The removal effect of the isolated fractions of recirculated leachate by the coagulation is HA>FA>HyI.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2005年第3期164-167,共4页
Environmental Pollution & Control
基金
国家"十五""863"计划课题资助项目(No.2001AA644010
No.2003AA644020)
