Waterflooding Adjustment Technical Evaluation And Application In Chaoyanggou Oilfield

Chaoyanggou Oilfield is a typical low ultra low permeability fractured reservoirs, since "the Tenth Five Year Plan", in accordance with the structural characteristics, storage layer, fluid properties and fracture development and development effect will be oil blocks was divided into three types, formed a "classification management, classification and Classified Governance" three development adjustment adjusting thought and practice.A block in 1986 and put into development, early in the development of the "two, three high, a timely development policy, in 1993 began the wells to inject row in high water cut oil well Zhuanzhu based injection production adjustment system, by the original anti nine injection area gradually turned into linear water injection, and combined with the water plugging, high containing wells shut in and other means to change the direction of liquid flow, so as to improve reservoir producing status and increased water flooding reserves, block development effect has been significantly improved, the natural decline rate is controlled within 10%. But with the extension of development time, the main problems in the development of a class of block is gradually exposed, the high production rate and the high degree of water flooding are high. With the increase of ineffective production, the oil displacement effect becomes worse, and the economic benefit is also changed. At the same time, remaining oil in all kinds of reservoir distribution scattered, due to the repeated application of layered water injection, cyclic water injection, profile control and other conventional water flooding adjustment, water flooding recovery rate can reach 30%, recovery degree of 24.7%, composite water cut 53.9%, block section has entered the development stage of high water cut and interlayer, areal producing degree is not balanced. We need to explore further improve oil recovery technology, therefore in a class of block selection to carry out block representative microbial flooding technology test, give full play to the role of leading technology, provide technical reserves for later development.At home and abroad by microorganism flooding oil test results show that, by using microbial decomposition and the decomposition process of the metabolites can play to reduce the viscosity of crude oil, enhanced oil flow coefficient, change oil-water interfacial tension, improve the efficiency of water flooding, so as to improve the oil well production and ultimate recovery. In addition, the domestic oil field development practice results also showed that the microbial enhanced oil recovery technology, especially for low permeability oilfield has obvious effect.Based on the above reasons, the field experiment of microbial oil displacement was carried out, and the experiment was carried out to form a kind of effective technology to enhance oil recovery. Through the optimization of a group using crude oil as carbon source and formation permeability phase matching of microbial enhanced oil recovery strain, and a large number of indoor evaluation, core flooding oil experimental research and field microbial stimulation measures and preliminary validation of the preferred species adaptability and effect. On this basis, toward the 50 block has launched a pilot test and extended test, test area in high water cut wells effect is obvious, and achieved the following understanding: is microbial strains to reservoir environment. To survive in the reservoir migration; second is preferably microorganisms, improve the fluidity of the crude oil, play the role of oil displacement agent; three is storage layer permeability in more than 6mPa?s can meet microbial survival and transport; four is in high water cut oil well microbial flooding oil effect is obvious; the fifth is microbial supporting the adjustment measures to promote microbial flooding effect, so as to improve the utilization rate of microbial, microbial flooding enhanced oil recovery, has achieved good economic benefits. Combined with microbial enhanced oil recovery characteristics, established microbial flooding numerical simulation component model to improve the micro-drive reservoir optimization design techniques.With laboratory experiments, numerical simulation and field test of the important parameters of microbial oil displacement amount, concentration, manner, period, interval, ratio of nutrient solution were optimized. Through laboratory experiments and numerical simulation studies to determine the microbial flooding expand test various injection parameters, experimental design microbial injection volume 0.03 PV, implant concentration of 2.0%, the proportion of liquid nutrition microorganism 1:1, the design of three cycles, which each year one cycle.Through the research of the project, deepen the microbial macro and micro displacement mechanism of oil; clear the oil reservoir conditions suitable for microbial displacement; optimize the microbial flooding technology of oil and the injection parameters; understand the microbial oil displacement effect rules; formed microbial stratification injection polymer profile control, microbial huff and puff of supporting technology, test area to enhance the recovery rate reached 4.95 percent, good technical and economic effect, with broad application prospects.