화학공학소재연구정보센터
Journal of the Electrochemical Society, Vol.166, No.16, E533-E541, 2019
Experimental Study on the Treatment of Oily Wastewater by Electrocoagulation with Aluminum Electrodes at Different Heights
H-2 bubbles produced at the cathode are beneficial for improving mass transfer within a batch electrocoagulation (EC) reactor. Increasing the thickness of the electrolytic bubble layer along the vertical electrode affects the distribution character of the oil concentration. This study aimed to explore oil removal from three layers relative to a series of vertically distributed aluminum electrodes; this type of exploration is crucial to understanding the demulsification process. The four factors of the initial pH, temperature and concentration of sodium chloride and the surfactant were investigated. Most micrometer-sized oil droplets on Layer A were obviously removed within the first 4 min, regardless of the sewage quality. The optimal pH value was 7.0, and the optimal NaCl concentration was 2 g L-1, which were demonstrated by the improvement in the overall demulsification performance. An increase in the emulsion temperature reduced oil removal from Layer C. Improvement in the oil removal efficiency of both Layer B and C was found to be crucial to the support of the overall demulsification process within the EC reactor. This result forms the basis for the industrial design of EC reactors and a way to determine its capacity in a variety of situations. (C) 2019 The Electrochemical Society.