Zeolite and pumice-amended mixtures to improve phosphorus removal efficiency of substrate materials from wastewaters

Abstract

Wastewaters discharged into receiving bodies without any treatments ultimately result in eutrophication in receiving bodies, generate mucilage problem and exert significant treats on aquatic ecosystems like the present devastating mucilage problem encountered in Marmora Sea of Turkey. Thus, wastewaters should pass through different treatment systems based on characteristics of wastewater effluents before to discharge them into receiving water bodies. In this study, phosphorus removal performance of different substrate materials (alone and in mixtures) was analyzed with filter column tests under laboratory conditions. Zeolite (Z), pumice (P) and sand (S) substrate materials were used alone and in different mixture ratios (75%–25 %, 50%–50 %, 25%–75 %). Different phosphorus concentrations (10, 20 and 40 ppm) were applied to filter columns and saturated columns were subjected to different hydraulic retention times (24, 48, 72 and 96 h). The greatest phosphorus adsorption was obtained from pumice amended mixture (75P-25Z). Present findings revealed that pumice amendments improved phosphorus removal performance of mixtures since increasing phosphorus absorptions were observed increasing pumice ratios of the mixtures. Pumice was found to be more effective than zeolite in improving phosphorus removal efficiency of the substrate materials. It was concluded based on present findings that pumice could reliably be used especially nutrient removal from wastewaters.