混凝沉淀法预处理填埋场调节池积存渗沥液的工程实践  

Engineering Practice of Landfill Leachate Pretreatment in Conditioning Pool by Coagulation and Sedimentation Process

作　　者：齐海浪 原效凯[1] 骆献达 QI Hailang;YUAN Xiaokai;LUO Xianda(Guangdong Architectural Design and Research Institute Group Co.,Ltd.,Guangzhou 510010,China)

机构地区：[1]广东省建筑设计研究院集团股份有限公司,广东广州510010

出　　处：《净水技术》2024年第11期157-163,共7页Water Purification Technology

摘　　要：通常当填埋场渗沥液调节池运行时间≥3年时,会在其底泥上部形成1~2 m的污染物浓度极高的渗沥液层(以下称“调节池积存渗沥液”),其SS、COD_(Cr)、氨氮等主要污染物及电导率往往是调节池底泥2 m以上液位的渗沥液(以下称“调节池正常液位渗沥液”)的8~10、2~4、2~6、1~2倍,且具有体量大、黏度低的特点。若采用人工清淤、吸粪车抽取等常规的清淤方式处理,则操作难度高、危险性大、经济成本高,若单独依靠常规渗沥液处理工艺也难以达标处理。文章系统论述了混凝沉淀法预处理调节池积存的高浓度渗沥液的工程案例,表明在反应pH值为6.5,混凝剂聚合硫酸铁(PFS)与絮凝剂聚丙烯酰胺(PAM)投加质量浓度分别为2461、56 mg/L时,该工艺对SS、COD_(Cr)、氨氮的平均去除率分别为79%、37%、13%。经测算设计处理规模为50 m^(3)/d时,该工艺的运行费用约为29.98元/m^(3)。该项目的成功实施表明,混凝沉淀预处理法具有操作简单、效果明显、适用水质范围广、耐冲击负荷高、成本低等优点,特别适合作为调节池积存高浓度的渗沥液的预处理工艺。In general,when the operation time of the leachate regulation tank in a landfill site is over 3 years,a leachate layer with a high pollutant concentration of about 1~2 m will be formed in the upper part of the bottom mud(this paper is collectively referred to as"leachate accumulated in the regulation tank").SS,COD_(Cr),ammonia nitrogen and other major pollutants and electrical conductivity are often 8~10,2~4,2~6,1~2 times of the leachate of the bottom mud of the regulating pond above 2 m level(referred to as"normal liquid level leachate of the regulating pond"),and it has the characteristics of large volume and low viscosity.If the conventional desilting methods such as manual desilting and extraction by suction truck are used,the operation is difficult,risky and the economic cost is high,and it is difficult to meet the standard treatment if the conventional leachate treatment process is used alone.This paper systematically describes the project case of coagulation and sedimentation pretreatment to adjust the high concentration of seepage deposited at the conditioning cistern.The results show that the average removal rates of SS,COD_(Cr) and ammonia nitrogen are 79%,37%and 13%,respectively,when the reaction pH is 6.5 and the mass concentrations of coagulant PFS and flocculant PAM are 2461 mg/L and 56 mg/L,respectively.When the design and treatment scale is estimated to be 50 m^(3)/d,the operation cost of the process is about 29.98 yuan/m^(3).The successful implementation of this project shows that the coagulation precipitation pretreatment method has the advantages of simple operation,obvious effect,wide range of applicable water quality,high impact load resistance and low cost,and is especially suitable for the pretreatment process of high concentration leachate stored in the landfill conditioning cistern.

关 键 词：调节池积存渗沥液 混凝沉淀法 渗沥液预处理 高浓度渗沥液 悬浮污染物 化学需氧量 

分 类 号：X703[环境科学与工程—环境工程]