一株高温解烃产黏菌的特性及其调剖驱油效果

Characterization of a mucoidal thermophile hydrocarbon-degrading bacterium and experiments on profile flooding

从油田地层水中分离出一株能在高温下降解烷烃并产胞外多糖的细菌DM-1,初步鉴定为芽孢杆菌(Bacillussp.)。该菌能在55℃高温缺氧条件下乳化并降解原油。在以原油为碳源的培养基中55℃培养5d,经红外分光测油仪测定,对原油的降解率达到61.51%。在高温和特定营养条件下,菌株DM-1可产生胞外多糖,经高压液相色谱分析,其组成糖为甘露糖(91.87%)、葡萄糖(7.95%)和半乳糖(0.18%)。对该菌产多糖的最适碳源和温度进行了优化,多糖产量可达1.7g.L-1。同时进行了岩心调剖和驱油物理模拟实验,结果表明,利用该菌株产生的胞外多糖能够将岩心注入压力由0.01MPa增加到0.40MPa,渗透率从3.856μm2降至1.589μm2,在驱油模拟实验中岩心后续水驱采收率为3.9%。利用环境扫描电镜观察了模拟岩心中该菌株的封堵效果。菌株DM-1在微生物采油中具有很好的应用前景。

Strain DM-1 which was identified as Bacillus sp. was characterized to degrade crude oil and produce extra cellular polysaccharide at a high temperature. At the temperature of 55℃, strain DM-1 could emulsify and degrade crude oil anaerobically. This strain could unitize crude oil as the sole carbon source and the degradation rate was 61.51%. It also produced extra cellular polysaccharide （EPS） in special medium at a high temperature. High performance liquid chromatography （HPLC） analysis of the EPS revealed that it mainly consisted of mannose （91.87%）, glucose （7. 95%） and galactose （0.18M）. Carbon source and temperature were optimized and EPS yield could reach 1.7 g - L-1. Manual cores were used to simulate the actual environment in petroleum reservoirs and the results showed that strain DM-1 could increase the pressure in the core from 0. 01 MPa to 0. 40 MPa and permeability was reduced from 3. 856 μm^2 to 1. 589μm^2. Oil recovery was increased by 3.9%. Environmental scanning electron microscopy （ESEM） technology was used to observe the microcosmic conditions in the cores. Strain DM-1 can be used in microbial enhanced oil recoverv （MEOR）.