Research And Application On Enhanced Oil Recovery Of The Ba 51 Fault Block Common Heavy Oil Reservoir

Ba 51 fault block which belongs to low and middle permeable,severely heterogeneous conventional heavy oil reservoir is the key reservoir developed by Erlian Field in recent two years. and waterflooding was performed in secession. Two problems existed in production due to the high oil viscosity and low formation temperature: one is due to the severe heterogeneity aggravates the difference of oil-water movement leads to the rapid increase of well water cut, thus, it influences oil production; another is due to the high oil viscosity, the formation has poor driving index and much slower energy-driven ,which leads to rapid production reduction after brought in, and it leads to bad reservoir injection development efficiency. therefore, how to control watercut increase in main productive layers is the key to realize stable production in fault blocks. Aiming to the present development characteristics and main development contradicts, Ba 51 fault block project made technical routes in accordance with reservoir geological characteristics, analysis of production contradicts from water-injection developments and technical treatment strategies in order to increase oil recovery. The technical routes are: in injection wells , perform engineering strategies that can increase swept volume and control oil water viscosity ratio; in production wells, perform engineering strategies that can dredge drainage channels, reduce oil viscosity and increase well productivity, to improve the injection development efficiency in Ba 51 fault block reservoir.The study in this paper conducted laboratory experiments study according to production characteristics exhibited from the well group in Ba 51 fault block reservoir and the gel flooding system formula optimization and microorganism viscosity reducer. Laboratory experiments and field applications proved this technical research results have positive effects on oil production and the economic benefits, thus, it has greater technical application and dissemination value.