Removal of oil from produced water using electrochemical method

Abstract

Abstract The produced water usually contains 1000 mg/litre of crude oil in dissolved, suspended and emulsion form. It is required to reduce the crude oil content to less than 40 mg/litre, to meet the latest discharge regulations. Current produced water technologies include centrifugation, compact floatation units, gravity settling, sand filtration, macroporous polymer extraction and ozonation. But their applications have certain disadvantages. This project is aimed to deal with the use of electro­chemical methods for the removal of oil from produced water and thereby reducing the environmental impact of produced water. An experimental setup for electro­coagulation, containing a stainless-steel cathode and a mild steel anode is used in the present study. In the electro­coagulation process, the coagulant is generated in situ by electrolytic oxidation of anode material, which facilitates agglomeration or coagulation of oil droplets and suspended solids and resultant separation from the aqueous phase. The response surface methodology software has been used to determine the relation between oil removal performance of the system and operating parameters such as current density, time and initial pH.