A Novel Bio-Eco Technology Combined System for Rural Domestic Wastewater Treatment in a Tourism Area: A Full-Scale Study

摘要

Characteristics of rural water consumption and sewage discharge in a tourism area were determined through an investigation of local villages in Lugu Lake (Yunnan Province). Based on the results of this evaluation, a novel bio-eco technology combined system was developed for high-quality wastewater treatment and recycling at low cost in the rural area. In this combined system, the bio-technique unit is an integrated oxidation ditch with vertical circle (IODVC), and the eco-technique unit consists of a wetland eco-filter, a subsurface infiltration and an eco-ditch. A full-scale wastewater treatment plant of this combined system was built in Lige Village, which is located at the Lugu Lake Tourism Area. The performance of the bio-eco combined system showed that its effluent quality reached up to grade III of the surface water standards (GB3838-2002), that is, the concentration of chemical oxygen demand ( COD), ammonia nitrogen (NH(4)(+)-N), and total phosphorus (TP) in final effluent was less than 10, 1, and 0.1 mg/L, respectively, whereas the COD of 140-300 mg/L, NH(4)(+)-N of 40-70 mg/L, and TP of 3-5 mg/L in the influent, respectively. Furthermore, evaluation of the P adsorption of the local soil revealed that the P was removed by the ecological treatment unit of the bio-eco combined system via the fixation and sorption of iron and aluminium in the soil. The effluent of the full-scale wastewater treatment plant was used as the source water of a local landscape ecological wetland. Results demonstrated that this bio-eco combined system could be a feasible technology for wastewater treatment in this kind of rural areas.