Industrial Dye Wastewater Treatment by Electrocoagulation

Abstract

Wastewater is not only one of the leading causes of permanent environmental damage, but it also contributes to the depletion of freshwater reserves on the planet, posing a major threat to future generations. Many industrial operations use a lot of freshwaters, dumped as wastewater. This wastewater must be treated adequately to decrease or eliminate pollutants and attain the purity level needed for re-use in industrial processes to ensure sustainability. Industrial wastewater contains a high concentration of organic pollutants that are active agents in water pollution. This research was conducted to remove various contaminants from industrial wastewater using electrolysis. Electrolysis is a very effective wastewater treatment method for removing contaminants and creating hydrogen gas as a revenue stream to compensate for operating costs. The removal efficiency of these treatments for chemical oxygen demand (COD), total suspended solids (TSSs), color, and turbidity from industrial wastewater was investigated using a simple electrolytic reactor at different electric current densities (CDs) and retention times (RTs). Our experiment observed that the highest removal efficiency for the parameters COD, TSS, turbidity, and color was obtained for 50V electricity and 4 hours RT, and the values are 73.92%, 91.67%, 73.63%, and 92.86%, respectively. It was also observed that as CD and RT increased, so did the removal efficiency of COD, TSS, turbidity, and color. Before the treatment, COD, TSS, turbidity, and color values for raw wastewater were 69 mg/L, 12 mg/L, 3.11 NTU, and 168 PT-Co, respectively. And after the electrocoagulation, COD, TSS, turbidity, and color values decreased to 18 mg/L, 1 mg/L, 0.82 NTU, and 12 PT-Co, respectively, for 50V electricity and 4 hours RT. However, as CD and RT levels increased, the parameters like pH, DO, salinity, TDS, and electrical conductivity (EC) also increased. It was noticed that the change in turbidity is proportional to the change in TSS. A linear and proportional relationship between EC and TDS was also observed in this study.