生态高负荷土地快速渗滤系统处理猪场废水的效能及微生态

Efficiency and Microecology of a Soil Infiltration System with High Hydraulic Loading for the Treatment of Swine Wastewater

以经过厌氧反应器处理后的猪场废水为研究对象,探讨了新型生态高负荷土地快速渗滤系统对废水中COD、氨氮及总氮的去除情况;同时分析了该系统中的微生物群落结构以及过氧化氢酶、脲酶、硝酸盐还原酶的含量.结果表明,在水力负荷为11 cm·d^(-1)、进水COD为700 mg·L^(-1)左右的条件下,一级土地渗滤柱与二级土地渗滤柱对COD的去除率分别为78.8%与63.0%,总去除率达到了92.6%;而当水力负荷增大到22 cm·d^(-1)时,总的COD去除率仍在90.0%以上;该系统对于氨氮的去除更为显著,去除率可达99%左右.一级土地快速渗滤系统中上、中、下部的过氧化氢酶含量分别为1.899、0.990、0.323 m L·g^(-1),表明猪场废水中的有机物主要在该系统的上部与中部得以去除;二级土地快速渗滤系统上、中、下部的硝酸盐还原酶含量分别是3.453、3.831、1.971 m L·g^(-1),表明脱氮作用主要发生二级土地快速渗滤系统的上部与中部.该土地快速渗滤系统中微生物以Gram Negative与Gram Positive为主,特别是在二级土地快速渗滤系统中,AM Fungi与Actinomycetes占有一定比例,为猪场废水中难降解有机物的去除提供了保障.

The swine wastewater after treated with an anaerobic reactor was used to investigate the removal efficiency of COD,ammonia nitrogen,and total nitrogen in an ecological high hydraulic loading soil infiltration system. Meanwhile,the microbial community structure and the contents of the catalase,urease,and nitrate reductase were analyzed. The results showed that with the hydraulic load of 11 cm·d^-1and the influent COD concentration of 700 mg·L^-1,the removal rate of COD was 78. 8%,63. 0%,and 92. 6% for the first land infiltration column,the secondary land infiltration column,and the total system,respectively. When the hydraulic load increased to 22 cm·d^-1; the total removal rate of COD was also above 90. 0%. The system was more significant for ammonia nitrogen removal. The removal rate of ammonia nitrogen reached approximately 99%. The contents of catalase were 1. 899,0. 990,and 0. 323 m L·g^-1at the upper,middle,and bottom sections of the system,respectively. The organic matter in the swine wastewater was removed at the upper and middle of the system. On the secondary soil infiltration system,the content of nitrate reductase was 3. 453,3. 831,and 1. 971 m L·g^-1,respectively. Denitrification mainly occurred in the upper and middle of the secondary soil infiltration system. Gram Negative and Gram Positive bacteria were given priority in the soil infiltration system. Especially,arbuscular mycorrhizal fungi and Actinomycetes dominated the secondary soil infiltration system. The system provides a guarantee for the removal of the refractory organic compounds from the swine wastewater.