Comparing a small gravel-less perforated pipe leach fields (GPPLF) to a medium one in treating domestic sewage

There were obvious differences between a medium gravel-less perforated pipe leach fields and a small system in the treatment of demestic sewage with the change of influent quality. In small system, COD removal rate was 91%, ammonia nitrogen removal rate was 90%, total nitrogen was 58%. In medium system, COD removal rate was 86.07%, ammonia nitrogen removal rate was 45.3%, and total nitrogen was 48.2%. This paper studied on the differences. Its main reasons were as follows: differences in opening rate (perforated area account of the total area in infiltration pipe), air flow conditions, exterior environment, and wastewater distribution. Considering those problems, Solutions and applications for the development of GPPLF are given.

无砾石微孔管地下渗滤系统试验研究

针对传统无砾石管式地下渗滤系统存在的处理性能差,渗滤通量低两个问题,通过去掉包裹织物,提高渗滤管开孔率、改变开孔方式,设计了无砾石微孔管地下渗滤系统。通过实验研究表明,无砾石微孔管地下渗滤系统对COD、氨氮的去除率比传统管式系统分别提高了10.8%、12.7%,总磷去除率并无显著差异,ORP值提高约85 mV,渗滤通量提高26.8%。在3.3 cm/d的水力负荷下,无砾石微孔管地下渗滤系统出水COD、氨氮、总磷平均浓度分别为19 mg/L,0.62 mg/L,0.048 mg/L。渗滤管下10 cm的土壤层去除了约70%的COD,80%的氨氮和91%的总磷,向下随着土壤深度的增加,单位厚度的土壤层去除的污染物量呈显著下降趋势。

无砾石管式地下渗滤系统的改进研究

针对传统无砾石管式地下渗滤系统存在的处理性能差,渗滤通量低两个问题,通过去掉包裹织物,提高渗滤管开孔率、改变开孔方式,设计了无砾石微孔管地下渗滤系统。通过实验研究表明,无砾石微孔管地下渗滤系统对COD、氨氮的去除率比传统管式系统分别提高了10.8%、12.7%,总磷去除率并无显著差异,ORP值提高约85mV,渗滤通量提高26.8%。无砾石微孔管地下渗滤系统和传统管式地下渗滤系统对COD、氨氮在土壤中的降解趋势线存在明显的差异,而对磷的去除过程几乎完全相同。

无砾石微孔管地下渗滤中试系统的实验研究

在无砾石微孔管中试系统中,设置了土壤、植物、管径三个参变量进行正交实验,对系统中各个单体产生的不同处理效果进行分析,并研究了降雨量、温度、进水水质对污染物去除率的影响。结果表明:大管径和砂壤土处理效果较好,系统中氮的去除率随进水浓度和气温变化较大。