Policy Analysis Method And Application Of High Pressure Water Injection In Tahe Fractured-cave Reservoir

The main reservoir spaces of Tahe fractured cavern type carbonate reservoir are large caves,corrosion holes and fractures.Because of the complex and diverse sedimentary environment,early accumulation time,large burial depth and many times of tectonic evolution in the later period,the reservoir space distribution has the characteristics of discontinuous,highly discrete and highly heterogeneous.There are many types of reservoir space in fractured-cave carbonate reservoir,and the distribution of reservoir space is quite random,horizontal and longitudinal distribution is discrete,which makes the flow law of reservoir fluid very complicated.Taking Tahe Oilfield as the test base,this paper optimizes the demonstration area of high-pressure water injection technology,studies,formulates the analysis method and application of high-pressure water injection policy,The conventional water flooding black oil model is established by using Eclipse reservoir numerical simulation software.In order to better apply the policy analysis method of high pressure water injection in fractured cavern reservoir,combined with the analysis of the main control factors of high pressure water injection in fractured cavity reservoir,three typical well groups are selected to do the application research of high pressure water injection technology policy.effectively maintains the formation pressure level,and controls the rise of water cut.As a result,the water injection efficiency of fracture-cave carbonate reservoir in Tahe oilfield is improved.In view of the development of water injection unit in Tahe Oilfield,this paper analyzes the weight of influencing factors of water injection,establishes the technical policy analysis method of high pressure water injection,and makes water injection policy of high pressure water injection wells for different types of reservoirs.The production effect of high pressure injection wells has been analyzed.The correlation between injection pressure and oil production of high pressure injection wells has been calculated by principal component analysis method,and the criterion of downpressure well selection has been established.Further use of high-pressure water injection technology policy analysis method.In order to develop high-pressure water injection technology in fractured-cavern carbonate reservoir,high-pressure water injection policy is made for different types of reservoirs,and according to the units requiring depressurization water injection,well selection criterion and depressurization countermeasures are established.Through demonstration and application,the technology of high pressure water injection in fractured cavern carbonate reservoir is further perfected,which provides technical support for the realization of the target of Tahe oilfield demonstration project.