An investigation on flow dynamics in the electrochemical reactor for the treatment of pharmaceutical wastewater

Abstract

In this study, the flow dynamic behavior of cylindrical electrochemical reactor (CER) has been investigated for the treatment of pharmaceutical effluent. The residence time distribution is considered as a tool to investigate the flow dynamic behavior of the electrolyte within the reactor. The reactor is operated at fixed current density of 2.5 A/dm 2 with lead oxide/ titanium as electrode by varying flow rates such as 50, 60, 70, 80 and 90 L/h. Impacts of various flow rates on flow dynamics were examined. The outcomes of this study demonstrate the presence of a dead volume and short circuiting in the reactor were reduced for the optimum flow rate of 70 L/h in the reactor. The potential of the CER was experimentally validated by analyzing the chemical oxygen demand (COD) removal efficiency, color, total dissolved solids, suspended solids and odor emanating from the effluent. Findings of this study reveal that maximum COD reduction of about 85.71% with minimum energy consumption of 63.82 kW h/kg COD at a flow rate of 70 L/h, which has good mixing and less backmixing condition inside the reactor. The experimental findings prove that the CER with a cylindrical mesh electrode can be used for the treatment of pharmaceutical effluents and is capable of achieving the quality of pharmaceutical effluents treated wastewater to the reuse standard prescribed for pharmaceutical industries.