Treatment of oily wastewater by electrocoagulation technology: A general review (2018-2022)

Abstract

A huge amount of oily wastewater is discharged annually from several industries like petroleum and petrochemical factories. Scientists and researchers are permanently concentrated on creating conventional technologies or identifying novel treatment options for oily wastewaters, since they need to be treated before being discharged into the soil and aquatic ecosystems. Electroc­oagu­lation technology (ECT) is an electrochemical method employed to remove numerous pollutants from domestic and industrial wastewaters. This paper aims to review the recently published articles from 2018 to 2022 concerned with ECT for oily wastewater remediation. Based on the present review, it is obvious that ECT is strongly dependent on the value of electric current or voltage applied to provide the required amounts of electro-coagulants for efficient remediation, reaction time duration for the generation of electro-coagulants and pollutants elimination, and electrode configuration such as shape, type of metal, and distance between electrodes. Other operating parameters include solution pH (since some pollutants are removed based on their cationic or anionic nature), type of electrolyte which affects the electric conductivity and ohmic drop and stirring speed that may influence the contact among numerous ions throughout the EC reactor. The core findings show that the ECT is highly effective, eco-friendly, and cost-effective in eliminating organic and inorganic pollutants from oily wastewater.