土壤渗滤系统中污染物去除效果分析

在土壤渗滤系统中,水力负荷、有机负荷和碳氮比等因素均对营养盐的处理效率具有显著影响.在实验室控温条件下,分析了不同水力负荷、有机负荷和环境条件对土壤渗滤系统污染物去除效果的影响.结果表明,在水力负荷小于0.15 m3·m^-2·d^-1的条件下,模拟生活污水中CODCr、总氮和总磷去除率分别达到84％、37％和93％以上,土壤（以干土计）亚硝酸盐细菌数量为4.50× 106 g^-1.装置上层产生的滞水对CODCr和磷酸盐的去除影响不大,但是由于处理系统内溶解氧浓度降低,使得氨氮硝化过程受到抑制,氨氮和总氮的处理效果均变差;在通气良好条件下,较高的碳氮比m（碳）：m（氮）=5：1]对系统中总氮的去除更为有利.

Removal of Pollutants From Soil Infiltration Systems.

Hydraulic load,organic load and the C/N ratio are main factors affecting nutritive salt removal efficiency of wastewater soil infiltration systems.In a laboratory with controlled temperature,effects of hydraulic load,organic load and environmental conditions on pollutants removal efficiency of soil infiltration systems were analyzed.Results show that when hydraulic load was lower than 0.15 m^3 · m^-2 · d^-1,removal efficiencies of CODCr,TN and TP in simulated domestic sewage reached over 84%,37% and 93%,respectively,meanwhile the number of Nitrosomonas was up to 4.50× 106 per gram dry soil.The perched water in the upper layer of the installation did not affect much the removal efficiencies of CODcr and phosphates.However,as a result of lowered dissolved oxygen in the system,nitrification of ammonia nitrogen was inhibited and the removal efficiency of ammonia nitrogen and TN lowered.Under the condition of enough DO,higher C/N ratio （5：1） was conducive to TN removal efficiency in the system.