Effect of Soil Microbes on Nitrate, Phosphate and Total Hydrocarbon Content of Various Concentrations of Oilfield Wastewater

Abstract

The effects of soil microbes on nitrate, phosphate and total hydrocarbon content of various concentrations of oilfield wastewater were investigated for a period of 28 days using standard methods. Periodic sampling of the treatment options from each flask were carried out after 24 hrs and subsequently at 7 days interval for nitrate, phosphate and total hydrocarbon content analysis. The nitrate, phosphate and total hydrocarbon content were higher in all the treatment options than in the control (0%). The concentration of nitrate and phosphate in the soil treatment options reduced significantly at day 28. Total hydrocarbon content of the 0% (control) on 24 hrs was 48 mg/kg and 26 mg/kg on 28th day, while 10, 25, 50 and 75 (%) were 160 and 98, 162 and 94, 163 and 98, 163 and 96 mg/kg respectively. There was significant reduction between the incubation period (24 hr and 28 days) in the various treatment option including the control.  The results revealed that nutrients (nitrate and phosphate) were been utilized by the soil microbes and further enhanced microbial utilization of hydrocarbons. This suggests that oilfield wastewater could serve as nutrient enhancement medium for indigenous soil microbes in bioremediation process.