Soil Infiltration Process Research Articles

Treatment of domestic wastewater by an underground capillary seepage system

The article presents a case study on the treatment of domestic wastewater using underground capillary seepage system. The system, which combines sedimentation, soil infiltration and biofilm processes, was designed to treat domestic wastewater from toilet, bathroom and restaurant. During the 3-year operation, performance of the system was found to be excellent with the removal rates of 92.6, 97.6, 86.8 and 81.72% for chemical oxygen demand (COD), biochemical oxygen demand (BOD 5), suspended solid (SS) and NH 4 +-N, respectively. The effluent of the system was able to be used to water lawns, flush roads or rinse toilets. Our study indicated that the percentage of wastewater that can be reused amounts to more than 70% through the system.