Characterization of Oily Wastewater Key to Proper Design and Maintenance of Oily Waste Water Separators - A Case Study of Niger Delta Region

Abstract:

Environmental regulation of oily waste water discharges are becoming more stringent. Oil industrial facilities have a number of possible applications for coalescing plate separators. These applications include flow stations, tank farms, process drains, Shipboard oily wastewater and runoff from oil spills. In recent years, it has become obvious that many of the oily waste water separators installed in the oily waste water facilities are not performing as anticipated. Several authors have pointed out the need to improve the design procedure of oil-water separator. The issues arising from poor design, improper selection of pre- manufactured off- the-shelf coalescing unit attributed to failure of understanding the character of oily waste waters being treated or pretreated. The sampling station investigated consist of three effluent receiving sites in the okrika arm of the Bonny River and the control sites at Elechi creek, all in the Niger Delta area. The result of characterization showed that maximum and minimum Temperatures are 20 and 18.310C, Specific gravity of waste water at maximum and minimum temperature are 0.994 and 0.986. Also specific gravity of oil in the waste water at maximum and minimum temperature are 0.873 and 0.845 while dynamic viscosity of oil waste water at maximum and minimum temperature are 0.00127 and 0.00132 N/m2.s. Also physico chemical characteristics at maximum and minimum values showed that pH are( 8.80 and 8.50), Conductivity (215.0 and 214.0 µS/cm), Total dissolved solid ( 165.50 and 159.58 mg/l), Total suspended solid ( 64.41and 61.79 mg/l), Salinity as Chloride ( 40.13 and 37.46 mg/l) while oil and grease ( 46.80 and 41.40 mg/l) Biological Oxygen demand ( 31.00 and 28.83 mg/l) and Chemical Oxygen demand (43.53 and 40.21 mg/l) . This characterization is useful in overall design, sizing of oily wastewater separator and separation efficiency.