Continuous electrocoagulation process for pretreatment of high organic load moquette industry wastewater containing polyvinyl acetate: a pilot study

Abstract

ABSTRACTMoquette-manufacturing industry is one of the textile industries that produces high organic load wastewaters containing polymeric adhesives, especially polyvinyl acetate (PVAc). The generated wastewater cannot be easily treated by commonly used traditional methods. Therefore, in this study, continuous electrocoagulation process (CECP) was applied for pre-treatment of real wastewater from moquette-manufacturing industry. For this purpose, the influences of different operational parameters, such as electrode distance, current density (CD), hydraulic retention time, and electrode type were investigated on the process performance at pilot scale. Under optimal conditions (neutral solution pH, optimum CD of 21 mA/cm2, Charge passed of 0.53 C/cm2 and hydraulic retention time of 25 min), the removal efficiencies of chemical oxygen demand (COD), total suspended solid (TSS), PVAc, total dissolved solid (TDS) and electrical conductivity (EC) using the CECP with Fe–Fe electrode (as the best electrode) were 90.4%, 91.3%, 93.9%, 59.7% and 72.6%, respectively. The results showed the process efficiency increased with decreasing electrode distance, and increasing of CD and retention time. The consumption rate of electrical energy increased with increasing electrode distance, CD and reaction time. Under the optimal conditions, the consumption rates of electrical energy for iron and aluminium anodes were 2.4 and 6.1 kwh/m3, respectively. Also, the electrode consumption for removal of 1 kg of COD using iron and aluminium anodes at the optimum CD was 4.2 and 3.2 Kg/kg CODremoved, respectively. Therefore, it can be concluded that CECP can be used as an effective and economical method for pre-treatment of moquette industry wastewater compared with the traditional methods.