两株嗜热解烃菌对原油的降黏机制

引言微生物采油技术是通过微生物自身及其代谢活动作用于原油和油藏,从而提高原油采收率的一项采油技术[1-4]。按代谢类型划分,油藏微生物主要包括解烃菌、腐生菌、厌氧发酵菌、硝酸盐还原菌、硫酸盐还原菌和产甲烷菌等[5]。其中,解烃菌是能利用石油烃作为碳源生长代谢,并产生气体、有机酸、脂肪酸以及生物表面活性剂等代谢产物的一类微生物的总称[6]。这些代谢产物可进一步改善

Mechanism of crude oil viscosity reduction by two thermophilic hydrocarbon-degrading bacteria

Two thermophilic hydrocarbon-degrading bacteria,named N12-3 and Z3-14,were isolated from Zhan 3 block,Shengli oilfield.16S rRNA gene sequence analysis indicated that N12-3 belonged to Bacillus sp.and Z3-14 belonged to Geobacillus stearothermophilus.The n-alkane components with carbon number under 20 were preferably degraded by N12-3.After degradation,the content of alkane hydrocarbons,aromatic hydrocarbons and resin decreased by 3.59%,11.24% and 10.08% respectively,while asphalt increased by 26.01%.Furthermore,∑C_21-/∑C₂₂₊ decreased from 2.62 to 0.74.On the other hand,longer n-alkane components were preferably degraded by Z3-14.After degradation,the content of saturated hydrocarbons,aromatic hydrocarbons decreased by 6.8% and 14.39% respectively,while resin and asphalt increased by 13.57% and 1% respectively. Furthermore,∑C_21-/∑C₂₂₊ increased from 1.33 to 3.13.N12-3 could reduce oil viscosity by resin degradation,while Z3-14 could not.However,both strains could reduce oil viscosity by emulsification with bioemulsifiers secreted.The results suggest that microorganisms can improve oil mobility,mainly by emulsification but not by degradation.