Simple physical treatment for the reuse of wastewater from textile industry in the Middle East

In this work, different treatment methods for wastewater from textile washing operations in the Palestinian territories were studied. The goal of the treatment process was to enable the textile industry to reuse the wastewater in textile washing through simple, efficient, and cost-effective methodologies. Actual textile wastewater samples from local textile factories were used and were found to be highly polluted. The study focused on three main processes; sedimentation, coagulation, and adsorption. While sedimentation was found to reduce the total suspended solids (TSS) of the wastewater, coagulation had the additional advantages of lowering the chemical oxygen demand (COD) and achieving higher filtration rates. Four coagulants were tested, ferric chloride, ferrous sulfate plus lime, aluminum sulfate, and aluminum sulfate plus lime. While ferric chloride failed to perform effectively as a coagulant, the other three coagulants were fairly effective. Finally, to further lower the COD of post-coagulation treated water, adsorption using activated carbon was studied. It was found that carbon was effective in reducing the COD of the wastewater using reasonable quantities, where up to 98% COD reduction was achieved using 6 g carbon/L.