Water quality of effluent treatment systems from local batik industries

Abstract

Most of the batik premises are still dominated by small and medium enterprises (SMEs). Nonetheless, a conventional wastewater treatment unit is very expensive to be owned by them. Therefore, many local batik premises discharge their untreated effluents directly to the river, which can be potentially toxic and post a great threat to the environment. The government has started initiative collaboration with educational institutes to develop an affordable treatment system for batik effluents. For that reason, this study was carried out within three batik premises that were equipped with the treatment systems to evaluate their efficiencies. Each treatment system had a different approach in treating batik effluents: (1) Treatment system A started the treatment with screening (sand filtration), aeration, neutralisation (sulphuric acid), coagulation process, and activated carbon filtration; (2) Treatment system B used a similar treatment method as system A except that no coagulant was applied; and (3) Treatment system C starts with screening, neutralisation (sulphuric acid), two tanks of activated carbon filtration before going through the photodegradation process. Physical parameters such as pH, temperature, dissolved oxygen (DO), salinity, conductivity, total suspended solids (TSS), chemical oxygen demand (COD), and colour were measured before and after treatment to determine the effectiveness. The results showed that treatment system C had the highest COD reduction of 91%, followed by treatment systems A and B. Treatment system C also achieved 86% of decolourisation, followed by treatment system A with 82%. Almost all the parameters measured from this study met the Environmental Quality Act (EQA) 1974 (Industrial Effluents) Regulations after the treatment process. The finding from this study should help with the development of any future recommendation and improvement of the treatment system for batik effluent discharges.