Bioremediation of Petroleum Refinery Wastewater Effluent via Augmented Native Microbes

In Nigeria, like other developing countries, industries discharge their wastewater without effective treatment due to the high cost of existing treatment technologies. Wastewater containing petroleum hydrocarbon is highly toxic and pose a great danger to the nearby communities. Therefore, there is a need for a more robust and cost effective treatment technology. In this research, a study was carried out on bioremediation of petroleum refinery wastewater via augmented native microbes. Four dominant microbial strains isolated from the petroleum refinery wastewater were identified to be Bacillus subtilis (S1), Micrococcus luteus (S2), Staphylococcus aureus (S3) and Staphylococcus epidermidis (S4) base on their gram reaction, morphology, microscopic appearance, and biochemical characteristics. The four strains showed their capability to degrade hydrocarbon as indicated by their growth in Bushnell-Haas medium. The four native microbes were used to boost the performance of the indigenous microbes (note that only two out of these four strains were used to boost bioremediation). Five different treatments (T1-T5) were investigated for 63 days. T1 (Natural attenuation) showed O&G degradation of 15.23 %. T5 (Aeration + Bioaugmentation with S1 & S2) showed O&G degradation of 66.7 %. From the result of this study, it has been established that bioaugmentation with native microbes using treatment option five can be used to developed a robust, cost effective and environmentally friendly process for the treatment of hydrocarbon contaminated wastewater. __________________________________________________________________________________________