Experimental Study On Rural Sewage Treatment Of Anaerobic Filter With Self-filler Made By Recycled Plastic/Wetland

According to the characteristic of rural decentralized sewage and the backwardness of economic and technical in countryside, In this paper, "anaerobic filter/wetland" a combination of biological and ecological proposed. In order to further reducing capital investment, changed filler in anaerobic filter with self-filler. Though a series of experiments, the self-filler can replaced the traditional filler, and without greater impacts on the removal of filter. At the same time determined the suitable HRT of the combined process, optimized wetlands and research on the removal of nitrogen and phosphorus in wetlands. And the main research achievements are as follow:(1)Study on whether the self-filler with recycled plastic as raw material was practical, including:the aspect of principles of filler selection, like, shape, mechanical strength, biochemical stability, porosity and etc. And the aspect of practicability, compared with the filter using suspension filler balls. Though changing the HRT of the filter, compared about the removal of CODcr, TP, NH4+-N and TN. Although the removal effect of filter using suspension filler balls was better, but difference was not great, and the self-filler was practical.(2)When the HRT=6h, the removal effect of the anaerobic filter was better. The removal efficiency of CODcr, TP and TN in the filter using self-filler were 62.48%,9.79%and 10.37%, and the concentrations of average effluent is 65.01mg/L,3.79mg/L and 32.53mg/L. The removal efficiency of CODcr, TP and TN in the filter using suspension filler balls were 67.16%,11.97% and 8.25%, and the concentrations of average effluent were 57.03mg/L,3.71mg/L and 32.65mg/L.(3) Research on the removal efficiency of CODcr, TP, NH4+-N and TN, determined a better HLR of wetland. By analyzing, the wetland was high removal efficiency in 0.122m3(m2-d)"1. The removal efficiency of CODcr, TP, NH4+-N and TN of the wetland were 47.9%,25.05%,31.34% and 27.7%, and the concentrations of average effluent were 32.64mg/L,2.71 mg/L,28.34mg/L and 23.34mg/L.(4)While the HRT=6h, the HLR=0.122m3(m2·d)1, the removal efficiency of CODcr, TP, NH4+-N and TN were 80.74%,32.81%,22.69% and 34.15%. Except CODcr, the removal efficiency were too low to meet standard. So add intermittent aeration to the wetland to improve the removal efficiency of nitrogen and phosphorus. When the gas-water ratio was 6, the removal was better. The removal efficiency of CODcr, TP, NH4+-N and TN of the wetland were 84.25%, 73.58%,69.31% and 65.11%, and the concentrations of average effluent were 21.92mg/L, 1.00mg/L,6.82mg/L and 12.53mg/L, meet the "urban sewage treatment plant pollutant discharge standard"(GB 18918-2002) in a B standards, CODcr and TN meet A standard.Research shows that:anaerobic filter with self-filler made by recycled plastic/wetland is an efficient and economize combination.