Analysis of the Reduction in Pollutants from Oilfield Wastewater on the Receiving Environment

Abstract

Oilfield wastewater from discharge pond and soil around the discharge pond of an oil producing vicinity were collected using standard procedures. The heavy metals and physicochemical constituents of the soil and wastewater from the receiving pond were examined according to normal procedures in compliance with the Environmental Protection Agency. The presence of negative numbers in the results indicates that there was an influence on the physicochemical parameters. It was discovered that the salinity of the soil surrounding a discharge pond was-73.80±53.20 mg/kg during the rainy season. Soil moisture content recorded a negative value of -43.77±9.477 during the rainy season. Potassium, nitrate, phosphate, calcium, magnesium, sulphate, total nitrogen, organic carbon, zinc, and copper recorded negative values in both dry and raining seasons. However higher values of -2309±486.4 mg/kg for potassium, -450.3±65.30 mg/kg for phosphate, -2779±274.2 mg/kg for calcium, -717.4±80.53 mg/l for zinc were obtained during the dry season. High values of -133.4±8.937 mg/kg for nitrate, -262.6±23.27 mg/kg for magnesium, -923.7±101.1 mg/kg for sulphate, -133.3±15.09 mg/kg for total nitrogen, -2788±276.9% organic carbon, -275.7±39.28% for TOM, -3.567±9257 mg/kg for alkalinity and -114.0±77.45 mg/l for copper were obtained during the raining season. For the wastewater from the receiving pond during the dry season, total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), nitrogen, phosphate, and polycyclic aromatic hydrocarbon recorded negative values of -4083±4.122 mg/l, -18.33±9.208 mg/l, -18.33±9.208mg/l, -70.35±39.50 mg/l, -312.9±170.7 mg/l and 617007±3.93 mg/l, respectively. High negative values during the raining season were obtained in turbidity (-17.57±94.87 NTU), TSS (-303.7±54.37 mg/l), TOC (-6276±6.294%), and total petroleum hydrocarbon (-105.1±162.1 mg/l). The heavy metals recorded high negative values of -6767±809.0 mg/l for lead, -14433±238 mg/l for chromium, -3317±2347 mg/l for copper, and -1967 ±66.67 mg/l for cadmium during the rainy season. High values obtained in the dry season were -59668±34243 mg/l for zinc and -2213±1472 mg/l for a nickel. The results suggest that oilfield wastewater impacts the receiving environment negatively.