干旱区生态环境知识资源中心

Urban wastewater is widely used around the world as a source of water, especially in arid and semi-arid areas. According to continuous municipal wastewater production through out the year and also due to prevention of environmental pollution, utilizing wastewater for artificial recharge is one of the most highly recommended methods. With respect to the processes in the soil vadose zone and subsequently in the aquifer, this method would improve wastewater quality and the so-called soil aquifer treatment (SAT). In this study, the recharge of urban wastewater in groundwater and also the effect of absorbent such as hematite-grafted non woven geo textile to increase the capacity to remove pollutants of this system were assessed. In order to perform the experiences and to control all conditions precisely, six SAT columns with an inner diameter of 20 cm and height of 2 m were used for 8 m. The columns were poured from sandy-loam soils and three absorbent layers to improve the reduction of pollutants. Its common practice was to operate SAT under a cyclic wetting and drying regime to simulate the real scenario. Applied management options include permanent flooding option as short-term periods (2-d wetting/2-d drying), medium term periods (7-d wetting/7-d drying) and long-term periods (14-d wetting/14-d drying).