He Technical Policy Of Water Development For Chang 2 Reservoir In T Oilfield

The Chang 2 reservoir of the T-zone in Ordos Basin has the characteristics of low porosity,low permeability,low pressure and high anisotropy,and has long been used in the barefoot well completion and production by natural energy,which has a serious formation energy deficit,low yield and downward trend.Since 2013,the research area has been produced by means of water injection development,and after a period of stable production,the oil production is now facing the problem of rapid decline and increase of moisture content.In order to deal with the problem of poor development effect of the research area,this paper,based on the analysis of geological characteristics and production situation of the research area,evaluates the present situation of water injection development by using reservoir engineering and numerical simulation method,puts forward the adjustment scheme and determines the injection-production parameters.Based on the reservoir engineering method,the dynamic characteristics and yield variation of the research area are analyzed,and the water content variation is evaluated by the method of comparing the theoretical moisture content curve and the actual curve,and the recovery rate of the research area is predicted by using the child's chart method and the water drive curve characteristic analysis and evaluation.Using the new type of water flooding characteristic curve method,the reserve utilization degree of the research area is evaluated,and the comprehensive decline rate of oil quantity is used to evaluate the stable production capacity of the old well.It was found that there was a sharp increase in water content and a rapid decline in production.Based on the study of the water injection well group and its effect direction analysis,the maximum principal stress direction and the sedimentary distribution direction,combined with the neighborhood experience,the water injection development adjustment principle which accords with the actual situation of the research area is proposed.On the basis of establishing reservoir numerical model and analyzing remaining oil distribution characteristics,taking into account the principle of water injection development and adjustment,this paper puts forward the plan of water injection development and adjusting,and uses reservoir engineering method and reservoir numerical simulation means to determine the development plan.By comparing the different schemes before and after adjusting the reservoir numerical simulation,the recovery ratio of the oil field was increased by 5% and the water content decreased by 2%.The research results can provide guidance for the improvement of the technology policy of water injection development in the research area,and can help to study the efficient development and long-term stable production of Chang 2 reservoir,and help to improve the oil recovery rate.