Turbidity and oil removal from oilfield produced water, middle oil company by electrocoagulation technique

Huge quantity of produced water is salty water trapped in the oil wells rock and brought up along with oil or gas during production. It usually contains hydrocarbons as oil and suspended solids or turbidity. Therefore the aim of this study isto treat produced water before being dischargeto surface water or reinjected in oil wells. In this paper experimentalresultswere investigatedon treating produced water (whichisobtained from Middle Oil Company-Iraq), through electrocoagulation (EC). The performance ofEC was investigated forreduction ofturbidity andoil content upto allowable limit. Effect of different parameters were studied; (pH, current density, distance between two electrodes, and electrolysis time). The experimental runs carried out by an electrocoagulation unit was assembled and installed in the labandthe reactor was made of a material Perspex, with a capacity of approximately 2.5 liters and dimensions were 20 cm in length, 14 cm in width and 16 cm height. The electrodes employed were made ofcommercial materials. The anode was a perforated aluminum rectangular platewith a thickness of 1.72 mm, a height of 60 mm and length of 140 mm and the cathode was a mesh iron. The current was used in the unit with different densities to test the turbidity removing efficiency (0.0025, 0.00633, 0.01266 and 0.0253 A/cm(2)). The experiment showed that the best turbidity removing was (10, 9.7, 9.2, 18 NTU) respectively. The distance between the electrodes of the unit was 3cm. The present turbidity removing was 92.33%. A slight improvement of turbidity removing was shown when the distance between the electrodes waschanged from 0.5 to 3 cm with fixation of current density. The best turbidity removing was 93.5%, (7.79 NTU) when the distance between the electrodes were1 cm. The experimental results found that concentration of oil haddecreased to (10.7, 11.2, 11.7, 12.3) mg/l when different current densities (0.00253, 0.00633, 0.01266, 0.0253) A/cm(2) were used, respectively with the distance between the electrodes was 3 cm. The best result of oil content decreasing was 10.7 mg/l with current density 0.0253 A/cm2. These results are within allowable limit to provide the possibility of reuse the water and can be injected in oil wells