Treatment of Dairy Industry Cleaning‐in‐Place Wastewater by Electrocoagulation Supported with Immersed Membrane Process

Abstract

This study aims to develop an easy and economic technique for dairy cleaning‐in‐place wastewater treatment to obtain high‐quality treated wastewater effluent. A batch electrocoagulation (EC) study is conducted using iron and aluminum electrodes. The effects of various operational parameters are investigated on the treatment performance. Maximum soluble chemical oxygen demand (COD) removal efficiencies of 81% for an Fe–Fe electrode and 53% for an Al–Al electrode are obtained at an applied voltage of 10 V, an electrode spacing of 2 cm, pH of 7.2, for a reaction time of 60 min. Moreover, protein removal efficiencies of 72.6 and 79.4% are obtained for Fe–Fe and Al–Al electrodes, respectively. An immersed membrane is integrated into the EC reactor and the reactor is operated in continuous mode. COD removal efficiency is determined as 86.4 and 84.5% for Fe–Fe and Al–Al electrodes, respectively, in continuous mode. The protein removal efficiency is also calculated as 80.9 and 83.8% for Fe–Fe and Al–Al electrodes, respectively. The Fe–Fe electrode shows the maximum COD removal efficiency, whereas Al–Al provides the maximum protein removal efficiency. Additionally, field emission scanning electron microscopy (FE‐SEM) and Fourier transform IR spectroscopy (FT‐IR) are applied to describe fouling phenomena.