In this study, attempts were made to examine the efficiency of radiation combined with coagulation with aluminium sulphate and adsorption using granular activated carbon (GAC) for treatment of paint wastewater and its reuse for different purpose. Parameters affecting microorganism disinfection such as radiation dose showed that complete disinfection was obtained at radiation dose 2 kGy. Factors affecting coagulation such as settling time, aluminium sulphate concentration were also studied, it was found that Al2(SO4)3.16H2O at concentration 10 g/L and pH 8 showed the better coagulation at 51 sec compared with other concentrations. A combined treatment of radiation followed by coagulation and adsorption by GAC of a dose (2 g/100 ml supernatant) showed a reduction in sulphate concentration 50%, COD 92% and BOD 98.5%. Also the obtained supernatant can be used for some irrigation purposes, whereas the coagulant was used as filler and showed the same physical parameters compared with the original one. Thus, this study might offer an effective way for wastewater treatment of paint industry.
Keywords: radiation dose, coagulation, paint industry, adsorption, wastewater treatment, paint wastewater, aluminium sulphate, granular activated carbon, GAC, microorganism disinfection