Study on the treatment of rural domestic sewage by mud membrane coupled integrated above-ground equipment: a case study of Putian, Fujian Province

Using a self-developed mud membrane coupling integrated process and its above-ground treatment equipment to centrally treat domestic sewage in a rural area of Putian City, Fujian Province, this study investigated the treatment efficiency and performance of the equipment during continuous and stable operation after installation and commissioning. Long-term on-site monitoring results showed that the average removal rates of COD, BOD5, NH4 ⁺ -N, TN, TP, and SS in the sewage were 86.8%, 89.7%, 93.9%, 83.6%, 97%, and 86.4%, respectively. The average effluent concentrations were reduced to 20.5, 7.95, 4.25, 13.65, 0.17, and 11.17 mg/L, respectively. The main water quality indicators of the effluent all met the Class A discharge standards of the Fujian provincial standard "Discharge Standard of Water Pollutants for Rural Domestic Sewage Treatment Facilities" (DB35/1869-2019). During the six months of stable operation, the equipment maintained stable performance and removal efficiency for various pollutants, with a maximum treatment capacity of 50 t/d. The operating cost of the equipment, excluding labor costs, was approximately 0.72 yuan/m3 . This equipment demonstrated strong resistance to pollution shock loads, effective sewage treatment, easy operation and management, stable performance, and relatively low operating costs. It can serve as a reference for other rural sewage treatment and remediation of black and odorous water bodies.