Reducing Oil Pollution in Kawergosk (Erbil-Iraq) Oil Refinery Effluent

The study of treating oily wastewater is crucial for environmental safety, as oil causes significant challenges to wastewater treatment processes. This chapter deals with the treatment of oily wastewater in a Kawergosk oil refinery. In Erbil city, surface runoff from each aspect of the greater Zab River mixes with the river water. Produced wastewater from the Kawergosk oil refinery can also blend with surface runoff and later input to the river, or it may also mix at once with water assets. Therefore, the classification of wastewater produced at the Kawergosk refinery is essential. The main objective of this study was to estimate the efficiency of dissolved air flotation in treating produced water from oil and grease production locations. The removal efficiency of the effluent was determined before and after treatment with respect to the oil content, chemical oxygen demand (COD), and biochemical oxygen demand (BOD). Three different factors, initial oil concentration (10–70 mg/l), pH (6–10), and feed rate (78–100 m3/h), were studied in the air flotation process while reducing oil and grease. In the dissolved air flotation experiments, the highest oil removal efficiency was 85%, with an optimum pH of 9, and feed rate of 88 and 92 m3/h. The percent removal efficiency decreased with increasing feed rate. The maximum percentage removal of COD and BOD ranged from 8 to 9. In addition, the results indicate that the characteristics of the initial oil concentration, pH, and feed rate directly affect the air flotation process during wastewater handling.