Study on the role of Nocardia farcinica in enhancing the flow rate of crude oil

Abstract

ABSTRACTMicrobial degradation of paraffin wax is an efficient method of removing wax deposition from pipelines and enhancing the flow rate of crude oil. The present study was carried out to isolate a potential paraffin-degrading organism from oil wells of Gujarat. Screening for bacteria-utilizing paraffin wax as the sole source of carbon was carried out using 2,6-dichlorophenol indophenol (DCPIP) dye as redox indicator. The selected organism was identified as Nocardia farcinica by 16S rRNA sequencing. Nocardia farcinica showed 100% degradation of heneicosane, 65.99% degradation of docosane, and 50.59% degradation of tricosane, the major components of paraffin wax, in 8 days, which was observed by gas chromatography. Eicosane (86%) and heneicosane (80%) were utilized more by the selected organism compared with octacosane (61%) and triacontane (58%) (DCPIP dye method). Gas chromatographic analysis revealed that the selected organism degraded 50% of paraffin crude oil in 10 days. To determine the ability of the selected organism to enhance flow rate, parameters such as viscosity (cps), surface tension (d/cm2), pour point (°C), and flow rate (min/2 ml) were determined, and the result showed significant reduction in all the parameters after the addition of Nocardia farcinica. The viscosity and surface tension of crude oil were reduced by 22 and 6.30 points, respectively, after the addition of Nocardia farcinica. Pour point and flow rate were reduced by 2 and 11 points, respectively, when compared with control. The above findings indicate that Nocardia farcinica isolated from crude oil plays a major role in enhancing the flow rate of crude oil.