低渗透油藏内源产分散体功能菌生长规律及其调驱封堵潜力

Growth Law of Indigenous Microorganisms Producing Dispersions in Low Permeability Reservoirs and Its Potential for Profile Control and Plugging

高怡文 魏登峰 王维波 倪 军 管雅倩 郭茂雷 王前荣 崔 凯

GAO Yiwen WEI Dengfeng WANG Weibo NI Jun GUAN Yaqian GUO Maolei WANG Qianrong CUI Kai

鄂尔多斯盆地延长油田特/超低渗透油藏由于基质渗透率低、非均质性强且普遍存在天然发育的微尺度裂缝，导致其在水驱、CO2驱等开发过程中面临流体易沿裂缝通道和高渗透孔隙喉道窜流的开采难题。传统调剖堵水技术在油田现场应用中的调剖范围仅限于近井地带，虽能改善注水井的吸水剖面，但流体在地层深部的水窜现象并未从根本上得到改善。针对这些问题，利用油藏微生物资源研发了基于内源微生物菌体及其代谢产物为生长晶核，且以单个个体形式生长分散在水相中的微小球体（即微生物分散体）的绿色低碳微生物分散体调驱封堵剂。结果表明，低渗透油藏产分散体功能菌种（Novosphingobium sp.，相似性98%～99%）的最优激活生长条件为：温度 45 ℃、矿化度 60 g/L、pH=7；最适宜的激活营养剂配方为：碳源（1.5%糖蜜），混合氮源（0.50%硝酸钠、 0.30%硫酸铵），微量元素（0.06%工业酵母粉、0.002%硫酸亚铁、0.002%硫酸锰）。初步探明微生物分散体调驱封堵作用机制为：产分散体功能菌利用个体的自适应生长性和形变性与储层裂缝通道形成匹配性的封堵，且不断向裂缝深部和高渗透多孔吼道的深部运移调驱，进而改变注入水/CO2气体的流向，最终实现全程调剖。微生物分散体在水驱/CO2驱环境中具有良好的调驱封堵能力，封堵率均大于80%。研究成果为微生物分散体调驱封堵技术在低渗透致密油藏水驱/CO2驱中调驱封堵储层裂缝窜流带、高渗透多孔介质窜流带和提高采收率的应用提供借鉴。

The tight-low permeability reservoirs in Yanchang oilfield of Ordos Basin are characterized by low matrix permeability，strong heterogeneity and widespread presence of naturally developed micro-scale fractures. These lead to the problem of fluid easily flowing along fracture channels and high-permeability pore throats during water flooding and CO2 flooding. Traditional profile control and water shutoff technologies are only effective in the near-wellbore area，which can improve the water absorption profile of injection wells but fail to fundamentally solve the water channeling problem in the deep formation. To address these issues，a green and low-carbon microbial dispersion profile control and plugging agent was developed based on endogenous microorganisms and their metabolic products as growth nuclei，which were dispersed as small spheres in the water phase （i.e.，microbial dispersions）. The results showed that the optimum activation and growth conditions for the microbial dispersion-producing functional strain（Novosphingobium sp.，similarity 98%—99%）were obtained as follows：45 ℃ temperature，60 g/L salinity，7 pH value. The most suitable activation nutrient formula was obtained as follows：carbon source（1.5% molasses），mixed nitrogen source（0.50% sodium nitrate，0.30% ammonium sulfate），trace elements（0.06% industrial yeast powder，0.002% ferrous sulfate， 0.002% manganese sulfate）. Meanwhile，the mechanism of microbial dispersion profile control and plugging was preliminarily clarified. The microbial dispersion-producing functional bacteria formed a matching plugging with the reservoir fracture channels by utilizing their individual adaptive growth and deformation properties，and then continuously migrated and controlled the profile in the deep part of fractures and high-permeability porous media，thereby changing the flow direction of injected water/CO2 gas and ultimately achieving full profile control. The microbial dispersion had good profile control and plugging capabilities in water flooding/CO2 flooding environments，with plugging rates all above 80% . The research results provided a reference for the application of microbial dispersion profile control and plugging technology in controlling the fracture channeling zones and high-permeability porous media channeling zones in low-permeability tight oil reservoirs and enhancing oil recovery.

10.19346/j.cnki.1000-4092.2025.01.015