Особенности разработки нефтегазоконденсатного месторождения Томской области

Abstract

Introduction. Oil and gas condensate field X is located in the Tomsk region and belongs to the Vasyugan oil and gas region of the West Siberian oil and gas province. In the section of the field, 5 development objects were identified: J1 1, J1 2, J1 3-4, J3 and J4-5. The studied objects are complex in terms of geological structure and phase state of the fluids. The factors complicating the development include low reservoir permeability, the presence of water-oil and gas-oil zones, the complex composition of the fluid, the phase state of the deposit is closeto critical. Studying the experience of developing complex objects is an urgent task. The resulting information can be further used in the design of the development of analogue deposits. Materials and research methods. The object of the study is the operational facilities of the oil and gas condensate field X. The article presents the results of the analysis of the development of the field; the dynamics of technological indicators, the structure of the fund, and the energy state of the commissioned facilities are studied. The design and technical documentation for the development of the X field was used as an information source, including the materials of studies by the pressure recovery curve (PRC) method, on the basis of which the effect of a decrease in reservoir pressure on the productivity of production wells was established. Research results and their discussion. At Field X, objects J1 1 and J1 2 were put into development, including oil and oil deposits with a gas cap. Gas condensate facilities are not operated. In general, the field is at the initial stage of development. For the J1 1 formation, according to the design document, a triangular well placement grid is implemented with a step of 700 m with the formation of an inverted seven-point flooding system. The J1 2 facility has a three-row development system 700 × 700 m. Despite the low porosity and permeability properties of the reservoirs, the input well flow rates are high, which is explained by the properties of the fluids of the X field. The only stimulation method currently used at the field is hydraulic fracturing. Adverse factors in terms of field development were identified during the analysis of the dynamics as regards the changes in reservoir pressure. A number of studies were carried out at the field to determine the effect of lowering reservoir pressure on the process of hydrocarbon production. Conclusions. In the course of the studies carried out at the field, an irreversible negative effect of a decrease in reservoir pressure below saturation pressure on well productivity was revealed. Gas/oil ratio growth is noted even with a slight decrease in reservoir pressure, especially in the J1 1 formation. The introduction of injection wells allowed stabilizing the reservoir pressure, but the main problems in the development of these complex objects remain unresolved. To optimize the further exploitation of these deposits, a comprehensive implementation of the proposed design solutions is required.