磁种混凝—磁分离技术预处理垃圾渗滤液的工艺研究
发布时间：2019-06-04 17:55
【摘要】：城市生活垃圾的主要处理方式是卫生填埋,由此产生了垃圾渗滤液,其性质和复杂的成分对环境危害大。在垃圾渗滤液的处理工艺中,混凝法可以适应渗滤液成分的不断变化,能稳定地去除大部分污染物。本研究主要以南宁市上林生活垃圾填埋场的垃圾渗滤液为研究对象,以氨氮和COD的去除率作为指标,利用磁种混凝-磁分离技术作为预处理工艺,进行了混凝剂筛选和条件优化的试验,确定最佳混凝剂、磁种混凝条件及磁分离条件。对药剂投加量、搅拌方式、温度、pH值、磁场强度、水样流速等影响因素进行了实验研究,并确定了处理该垃圾渗滤液的最佳工艺条件;探索了处理后的悬浮液的过滤特性。实验研究结果表明,聚合硫酸铁(PFS)是适合处理该垃圾渗滤液的最佳混凝剂;曝气处理能有效去除60%左右的氨氮和25%左右的COD。曝气处理后,该垃圾渗滤液的最佳磁种混凝-磁分离工艺条件为:25℃,pH=10.0,PFS投加量16g/L,磁种投加量30g/L,搅拌方式为先250 r/min搅拌4 min再100 r/min搅拌15min,PAM投加量20mg/L,磁场强度150mT,水样流速0.5 L/min。在此条件下,COD的去除率可达86.8%,含量为486mg·L-1,氨氮的去除率达到75.6%,含量为196mg.L-1。其中磁种混凝技术对氨氮和COD的去除起主要作用,而磁分离技术对氨氮和COD进一步的去除效果不大。过滤特性的研究结果显示,污泥沉降至相同体积时,磁混凝花费的时间比混凝-絮凝快了 3.4倍,且在沉降60 min后,磁混凝污泥体积比混凝-絮凝的少了近一倍;磁混凝的污泥比阻比混凝-絮凝的小了613倍,其过滤常数值是混凝-絮凝的2.85倍,更易过滤。磁种不仅可作为絮凝核心,强化沉降效果,还使絮团具有较强的磁性,令其在磁场中实现固液分离,提高分离效果。磁种混凝-磁分离技术能有效去除垃圾渗滤液中的氨氮和COD含量,其具有处理效率高、分离效果好、设备简单、占地面积少、易于实现净化一体化、自动化等特点,在污废水处理领域有着广阔的应用前景。
[Abstract]:The main treatment method of municipal solid waste (MSW) is sanitary landfill, which produces landfill leachate, whose properties and complex components are harmful to the environment. In the treatment process of landfill leachate, coagulation method can adapt to the continuous change of leachate composition and can remove most of the pollutants stably. In this study, the leachate of Shanglin Municipal solid waste Landfill site in Nanning City was taken as the research object, the removal rate of ammonia nitrogen and COD was taken as the index, and the magnetic coagulation-magnetic separation technology was used as the pretreatment process. The experiments of coagulant screening and condition optimization were carried out to determine the optimum coagulant, magnetic coagulation conditions and magnetic separation conditions. The influence factors such as dosage, stirring mode, temperature, pH value, magnetic field intensity and flow rate of water sample were studied, and the optimum technological conditions for the treatment of landfill leachate were determined, and the filtration characteristics of the treated suspension were explored. The experimental results show that polyferric sulfate (PFS) is the best coagulant for the treatment of landfill leachate, and aeration treatment can effectively remove about 60% ammonia nitrogen and 25% COD.. After aeration treatment, the optimum magnetic coagulation-magnetic separation conditions of the landfill leachate are as follows: 25 鈩，
本文编号：2492892
[Abstract]:The main treatment method of municipal solid waste (MSW) is sanitary landfill, which produces landfill leachate, whose properties and complex components are harmful to the environment. In the treatment process of landfill leachate, coagulation method can adapt to the continuous change of leachate composition and can remove most of the pollutants stably. In this study, the leachate of Shanglin Municipal solid waste Landfill site in Nanning City was taken as the research object, the removal rate of ammonia nitrogen and COD was taken as the index, and the magnetic coagulation-magnetic separation technology was used as the pretreatment process. The experiments of coagulant screening and condition optimization were carried out to determine the optimum coagulant, magnetic coagulation conditions and magnetic separation conditions. The influence factors such as dosage, stirring mode, temperature, pH value, magnetic field intensity and flow rate of water sample were studied, and the optimum technological conditions for the treatment of landfill leachate were determined, and the filtration characteristics of the treated suspension were explored. The experimental results show that polyferric sulfate (PFS) is the best coagulant for the treatment of landfill leachate, and aeration treatment can effectively remove about 60% ammonia nitrogen and 25% COD.. After aeration treatment, the optimum magnetic coagulation-magnetic separation conditions of the landfill leachate are as follows: 25 鈩，
本文编号：2492892
本文链接：https://www.wllwen.com/shengtaihuanjingbaohulunwen/2492892.html
