The effect of soil types on nitrogen and phosphorus removal from secondary treated municipal wastewater by using soil-aquifer treatment system

Abstract

In this study, the removal efficiency of nitrogen and phosphorus in secondary treated wastewaters with a laboratory scale soil-aquifer treatment system prepared using two different types of soils and the effect of soil types on treatment efficiency were investigated. In the columns filled with clayey loam soil (CLS) and loamy soil (LS), secondary treated municipal wastewater taken from the effluent of Denizli provİnce (Turkey) municipal wastewater treatment plant was used as feed wastewater. During the experimental studies, the total-N, total-P, dissolved oxygen, pH and temperature parameters were measured in the permeate samples taken from the valves at different depths attached to the columns. In the permeate samples taken from the last valves at a depth of 75 cm, total-N was 50.85% and total-P 97.07% in CLS, while these values were calculated as 36.72% and 64.43% in LS, respectively. In addition, the first 10 cm was highly effective for total-N and total-P removal in both soil types. Consequently, It was observed that TT was less effective than KTT in both total-N and total-P removal, the removal efficiency increased as the depth increased in both soils, and there was no time-dependent decrease in the removal efficiency during the experimental studies.