Pollutants Removal of Municipal Wastewater through Vertical Multilevel Soil Infiltration Treatment

Soil infiltration treatment was proved to be an effective and low-cost treatment technique for municipal wastewater in many areas. This system was intensified by combined stuffing (with zeolite, active carbon, sawdust and scrap iron) set for multilevel and named Vertical Multilevels Soil infiltration system (VMSI). Bench-scale soil column experiments were performed in laboratory to investigate effects for this kind of system. From the start-up to the 4th month, VMSI exhibited effective pollutants removals after maturation, with the highest removal efficiency 88% of chemical oxygen demand (COD), the highest removal efficiency 94% of total nitrogen (TN). Bench-scale soil column experiments were performed in parallel to compare aeration with non-aeration effects of this system, and found that removal efficiency of nitrate nitrogen(NO₃ ^--N) of the aeration columns were higher than the columns with non-aeration, it was also found that removal efficiency of nitrate nitrogen had direct relations with soil content. The objective of this paper was concentrate on pollutants removal by a VMSI system for the treatment of municipal wastewater.