生物填料地下渗滤系统处理生活污水的中试研究

以活性污泥等生物基质为填料.在不同的水力负荷和有机负荷条件下,研究了地下渗滤系统对生活污水的处理效果.中试结果表明:地下渗滤系统对COD、NH_4~+-N和TP有着良好的去除效果,在水力负荷为4 cm·d~(-1),污染负荷为280 mg·L~(-1)和320 mg·L~(-1)时.COD、NH_4~+-N和TP的去除去分别达到91.2%、97.2%、88.0%和90.6%、95.6%、90.4%;水力负荷达到450 mg·L~(-1)时,有机物及氨氮的去除率下降迅速,仅为83.2%和85.5%,TP的去除率略有提高,为91.7%;平均污染负荷为300 mg·L~(-1),水力负荷为4.0 cm·d~(-1)、6.5 cm·d~(-1)和8.1 cm·d~(-1)时,COD、NH+4_4~+-N和TP的去除率分别达到90.6%、97.4%、90.0%.87.3%、96.8%、84.0%和85.6%,96.3%,83.3%;适宜的生活污水处理条件是水力负荷为8.1 cm·d~(-1),污染负荷低于450 mg·L~(-1).在以上工况下的出水水质均优于生活杂用水水质标准(CJ251-89)和沈阳市污水处理中水回用标准,处理效果稳定;系统垂直方向的氨化细菌分布较均匀,硝化细菌在70 cm以上区域数量较多,反硝化细菌在70 cm以下区域数量较多;氨化细菌与COD、NH_4~+-N和TN的去除率的相关性显著,硝化及反硝化细菌与COD、NH_4~+-N和TN的去除率的相关性极显著;氨化、硝化和反硝化细菌与TP的去除率的相关性均不显著,说明生物作用不是TP脱除的主要途径.

Bio-filling substrate sewage infiltration system for the domestic waste Treatment

The paper is aimed to propose a pilot plant of subsurface sewage infiltration system (SWIS) filled with a bio-substrate for treating domestic sewage with pilot-scale experiments performed to study the effects of hydraulic and organic loadings on the removing rate of organic matter and ammonia. The experimental results show that SWIS had quite efficient removing effects of COD, NH_4~+ -N and TP.The exact average removing rates can be illustrated as follows: COD,NH_4~+-N and TP were 91.2%, 97.2%, 88.0% and 90.6%,95.6 %, 90.4 %, respectively, at the hydraulic loading 4 cm·d~(-1),organic loading ranging from 280 mg· L~(-1)to 320 rag·L~(-1). However,only 83.2% and 85.5% were found for COD and NH_4~+ -N when the organic loading was raised to 450 mg·L~(-1). At the same time, the removing rate of rip turned to be varied slightly at 280 mg· L~(-1)to 450 mg· L~(-1). As to the average removing rates of COD, NH_4~+-N and TP,they were respectively found to be 90.6%, 97.4%, 90.0%;87.3%, 96.8%, 84.0% and 85.6%, 96.3%, 83.3, when the organic loading was 300 mg· L~(-1) and the hydraulic loading varied from 4.0 cm·d~(-1) to 8.1 cm·d~(-1). The results of our experiments indicate that the optimal operation conditions for SWIS can be shown as follows: hydraulic loading: 8.1 cm· d~(-1) and that of organic loading:below 450 mg·L~(-1). Under the above conditions, the average effluent concentrations can be made to meet the standard of living sewage treatment (CJ 251-89) and the standards of the recycled sewage in Shenyang. It has also proved that the removing effects of this system prove to be stable and less affected from the outside environment. In SWIS with the hio-substrate, ammonified bacteria were found at a high level of activity in different depths with nitrifying bacteria at a high level of activity at 0 - 70 cm depth and denitrified bacteria in depth of 70 - 120 cm. A correlation analysis has been done with SPSS software, revealing that the amount of ammonified bacteria was in significant corelation with the removing rates of OD, NH_4~+ -N and TN whereas the amount of nitrified and denitrified bacteria were in close relation with the removing rates of NH_4~+ -N and IN. Nevertheless,the removing rate of TP has found no obvious correlation with that of ammonified, nitrified or denitrified bacteria, which suggested that TP removing process is irrelevant to the microbial activities.