Optimization of treatment process of Bushigan treatment plant in respect of turbidity and total organic carbon reduction

Abstract

Aims: The aim of the present study was to investigate the optimization of the treatment process of Bushigan water treatment plant (South of Iran) in respect of turbidity and total organic carbon (TOC) removal. Materials and Methods: The water samples were collected from Shapoor river the influent water to Bushigan treatment plant. A conventional jar test apparatus was used to evaluate the coagulation process. Different dosages of poly aluminum chloride (PACl), powdered activated carbon (PAC) and chlorine (Cl 2 ) alone and with each other was used to determine their effects on removal of the turbidity and TOC. Results: The average of TOC and turbidity in raw water were 5.81 mg/L and 29 NTU respectively in all seasons. The study result showed that the removal efficiency of TOC and turbidity were improved with increasing the PACl and PAC dose. With the application of 12 mg/L PACl alone, the maximum TOC and turbidity removal efficiencies were 41% and 31%, respectively. At constant PACl dose, application of PAC as coagulant aid and adsorbent improved the removal efficiency of TOC and turbidity. Conclusion: The results were showed that by common water treatment method (coagulation and precipitation) using PACl as a coagulant and also PAC and Cl 2 as an adsorbent and coagulant aid, the TOC and turbidity of water reduced to below 1 mg/L. So PAC and Cl 2 can improve the coagulation process. This method can be used for water treatment plant with drinking water contain the average TOC less than 6 mg/L.