Petroleum and oily wastewater treatment methods: A mini review

Abstract

The environmental effect of petroleum, refinery, and oily wastewater pollution is considerable owing to the large quantity of water produced throughout the process. Petroleum has mainly negative environmental effects due to its toxicity in nearly all lifestyles. Pollution of the air and water with oil may be harmful and hazardous to people's health. Petroleum industry effluent is often strong and may include hazardous contaminants. Inorganic and organic materials in various quantities, as well as heavy metals, surfactants, and other salts, are often found in wastewater generated by the petroleum industry. Discharging untreated or partly processed petroleum refinery effluents into the environment causes aquatic ecosystem pollution, an unsightly environment, expensive wastewater remediation costs, and the loss of cropland and fish. In the remediation of petroleum effluent, many traditional and common techniques such as biological, physicochemical, and chemical approaches are employed. Physical (mechanical) pre-remediation is often used to remove free oil, grease fractions, and suspended particles from petroleum effluent. The second step is a more advanced remediation that uses a mix of biological and physicochemical techniques to bring the contaminant level down to permissible discharge limits.