Determination of optimal bottomhole pressures of wells in a field or in a field area has been the subject of research for many specialists. Earlier works were focused on determination of limited bottomhole pressures, because it was generally accepted that limited bottomhole pressures ensure the most efficient and effective development of reserves. However, a more rigorous solution can be achieved through application of flow simulation and inverse modeling methods. Some approaches to solve this problem are discussed in this paper. To find optimal bottomhole pressure we have created models with different reservoir characteristics and fluid properties. The calculation results were analyzed considering specific reservoir conditions. We have revealed some principles that can be applied to improve performance of real oil and gas fields. The paper discusses the issues related to determination of pressure in fractured-porous reservoirs. It is common knowledge that these reservoirs are characterized by low oil recovery factor and low cumulative oil production. The research results show that the choice of optimal bottomhole pressure in fractured-porous reservoirs is largely dictated by presence or absence of gas-cut fluid flow. In case the bubble point pressure is close to the initial reservoir pressure, optimal bottomhole pressures differ significantly from limited bottomhole pressures and, thus, should be calculated both for production and injection wells, yet, within the range of limited bottomhole pressures. In case the bubble point pressure is lower than the initial reservoir pressure, limited bottomhole pressure is the right choice for production wells. As a side note, the highest cumulative production and NPV in fractured-porous reservoirs can be attained if reserves are produced by natural flow up to the point the reservoir pressure equals the bubble point pressure, so, water flooding to maintain formation energy should not be started until the reservoir is in solution gas drive. The revealed principles can be applied to improve production rates, cumulative production, and NPV of carbonate reservoirs.
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