Xifeng Chang8Reservoir Protection Technology Research In Early Water Injection

This article mainly studied technical problems that were High pressure water injection and High demand for reservoir protection, which were exposed at the development process of Chang8reservoir, the key production building block(Huan305-56、 Xi41block) of the second Oilfield factory. Geological feature researches about rock ore component analysis、 sensitivity evaluation and formation fluid properties analysis were done, high Betting early water injection pressure was finally determined, Combined with drilling and completion reservoir damage analysis and injection water quality analysis, aimed at the process of drilling and completion of the reservoir damage.The organic retarded acid system was determined. Indoor evaluation results showed that the NHS-1could relieve the damage in the process of drill completion. Maling chang8core damage rate was reduced to-18.6%, Xifeng chang8core damage rate was reduced to-3.6%after using the NHS-1; Because of water sensitive damage and reservoir scaling in early water injection. A set of anti bentonite antiscale was optimized and system performance was evaluated. The evaluation results showed that reservoir debris prevention expansion rate was above90%, calcium carbonate scale of anti-scaling rate was above95%, calcium sulphate scale anti-scaling rate was above90%, barium sulfate (sr) scale anti-scaling rate was above70%, the core displacement pressurea was reduced to9%, at last, the reservoir pretreatment technology"NHS-l Organic retarded aci+prevent bentonite antiscale slug was confirmed. The72Field application wells (there are48opened wells now) can decrease water injection pressure by about10%, contrasting conventional betting well. The slow after the betting the purpose of pressure rising too fast was Realized.