Comparative Efficacy of Coagulation-Flocculation and Advanced Oxidation Process (AOP: Fenton) for Textile Wastewater Treatment

Abstract

Textile effluent contains dye and harmful chemicals which are difficult to remove. This study was conducted to find out the cost effective and efficient textile effluent treatment process. In this regard, coagulation-flocculation and Fenton treatment process were applied in which pH, Dissolve Oxygen, TOC (Total Organic Carbon), COD (Chemical Oxygen Demand), TDS (Total Dissolve Solid) and EC (Electro-conductivity) were analyzed before and after the treatment. Conventional Jar test was used for coagulation and flocculation process where chemical coagulants (FeSO4 and Ca(OH)2) were added to different doses. On the other hand, Hydroxyl (OH.) radical, a byproduct of reaction between hydrogen peroxide (H2O2) and ferrous sulphate (FeSO4) was used in Fenton treatment processas a strong oxidant capable of oxidizing various organic compounds. In coagulation-flocculation process the maximum reduction of pH (6.3-6.8), TDS (400 mg/l), EC (1110 µs/cm), COD (86.56%) and TOC (97.81%) was found after using dose 1 (1 g of FeSO4 and 1 g of Ca(OH)2) which was within Bangladesh standard value. And DO (Dissolves Oxygen) was increased maximum 4.4 mg/L than the untreated (1.2 mg/L) effluent. In Fenton treatment process, maximum TOC removal efficiency was found at pH-1 as 89.45%. The COD content was also remarkably reduced as 63.98% at pH-2. It was observed that in comparison of removal efficiency coagulation-flocculation process was more efficient than Fenton treatment process. Concurrently both processes were proved very cost effective, time saving and easily operative for industrial use.