1株稠油降粘菌BIT-BS002的性质研究与矿场应用

从辽河油田稠油样品中筛选出1株高产生物表面活性剂的菌株。经形态观察、生理生化性质测试以及16S rDNA序列分析,鉴定为枯草芽胞杆菌(Bacillus subitlis),并命名为BIT-BS002。通过薄层色谱和红外光谱分析确定该菌所产生物表面活性剂为一种环脂肽类物质。该菌在50℃条件下培养24 h后可使发酵液表面张力由54.88 mN/m降至26.99 mN/m,同时对煤油和液体石蜡的乳化率分别为100%和94%。室内评价结果表明,菌株BIT-BS002对辽河油田稠油的降粘率达到81.93%,驱油效率可在水驱基础上提高14.75%。矿场试验进一步表明菌株BIT-BS002增油效率显著,单井吞吐井试可提高产量达施工前的3.86倍。

Characteristics and Field Application of Bio-Surfactant Produced by Bacillus subtilis BIT-BS002

A bio-surfactant high-producing bacteria strain was isolated from heavy oil sample from Liaohe oilfield. It was identified as Bacillus subtilis according to its morphological, physiological, and biochemical characteristics and 165 rDNA sequence analysis and named as BIT-BS002. The bio-surfactant produced by BIT-BSO02 was characterized by FTIB and TLC analysis, and its structure consists of a cyclic peptide sequence linked to a fatty acid. It could re- duee the surface tension of cultured medium from 54.88 to 26.99 mN/m after cultured for 24 h under 50 ~C. The e- mulsion separation rate of kerosene and liquid paraffin after treated by BIT-BSO02 were 100% and 94% , respectively. The results also showed the heavy oil viscosity reduction rate was 81.93% , and residual oil was recovered from sand~ stone cores over 14.75% compared to water flooding only. The field test of strain BIT-BSO02 already achieved good results in MEOR huff and puff, and the oil recovery was 3.86 times more than before the construction.