Effect of Natural Coagulants on the Treatment of Municipal Wastewater

Abstract

Nowadays, the study of the natural coagulants to treat wastewater has become a growing interest to the environmental researchers around the world as its numerous advantages over chemical coagulants. In this study, the effect of banana peel powder and banana stem powder as natural coagulant on the treatment of municipal wastewater was investigated. Wastewater samples were collected from two different primary drains located near Padma garden and Bornali within Rajshahi city corporation area. The collected wastewater samples were characterized based on turbidity, pH, conductivity, TDS, TSS, TS, alkalinity, acidity and organic content and also compared with maximum permissible limits before going treatment. The worst wastewater sample was treated with varying coagulant doses, contact time, speed and pH. The effectiveness of natural coagulants was evaluated based on the percentage removal of turbidity, alkalinity and acidity. The highest removal of turbidity, alkalinity and acidity were obtained 93.5%, 67.3% and 65.5% by banana peel powder and 93.4%, 71% and 72% by banana stem powder respectively. Therefore, the result revealed that both banana peel powder and banana stem powder had capability to treat municipal wastewater as natural coagulant. Higher treatment conditions were not economically feasible because it did not significantly remove the pollutants. The removal of alkalinity and acidity indicated that it was a partial coagulation and partial adsorption process in which both materials also had high adsorption capacities.