OIL FIELD EFFLUENT WATER TREATMENT FOR SAFE DISPOSAL BY ELECTROFLOTATION

Abstract

Large quantity of effluent is produced during the exploitation of an oil field which is separated at Process Platform. It is a tough emulsion, slightly turbid in nature and contains considerable amount of residual oil in the form of emulsion. It is hazardous to dispose such effluents without proper treatment. Free oil hinders the penetration of sunlight in river water distracting aquatic life and restricts natural cleansing of water in rivers or lakes. Bathing in contaminated oily water causes skin cancer. Free and emulsified oil can clog and coat the filters and ion exchange beds, decreases effectiveness of filtration and interface with backwashing. Various conventional methods like coagulation, flocculation, dissolved air flotation, etc. have not proved to be satisfactory, necessitating to work into alternative process of treatment for safe disposal. Attempt has been made to evaluate the electroflotation techniques for treatment of oil field effluent. In this technique the process of electrolysis initiated in the effluent by passing direct current in it through perforated aluminum electrodes. This results into separation of oil which forms a layer on the surface of effluent system. The separated oil on the effluent surface can be easily skimmed out. The batch process studies have been conducted to optimise electrical input in the effluent and it is observed that at 5.0 Volt & 0.4 Ampere current is optimum. Also oiI removal efficiency is high at 4.72 pH. It has also been observed that decrease in salinity and increase in oil content of the effluent enhances the efficiency of the electroflotation process.