Development and Study of a Decentralized Domestic Sewage Treatment Device

It is one of the main reasons for the rural water quality deterioration in the Jiaghan Plain area that rural domestic sewage was discharged without treatment. A small integrated device of rural sewage treatment was developed, based on the characteristics of the rural effluent household sewage of average 5 people per family in Jianghan plain and the technology of Japanese rural sewage treatment septic tank (Johkasou). The domestic fillers in the first anaerobic chamber, the second anaerobic chamber and aerobic chamber were chosen. The effluent water quality indexes such as COD, BOD₅ and TN had achieved the designed criteria after running near one year, which meet the national technical standards of rural environmental large zone remediation at present stage. The phosphorus removal efficiency was lower due to the influent TP concentrations exceeding the designed criterion. The annual effluent TP concentrations did not meet the design requirement and other phosphorus removal processing was needed to set in the device. This developed device is suitable for using in household living dispersedly in rural areas, villas and scenic spots that there are advantages of easy installation, a small sewage treatment capacity, low operating cost and a simple management procedure.