A Characterization Method of Gas-oil Ratio Increase Rate in Gas Injection Development Reservoirs

Abstract

The invention relates to a method for characterizing the gas-oil ratio increase rate of a gas injection development reservoir, which comprises the following steps: 1) determining the gas saturation at the outlet according to the material balance equation and the relationship between the gas saturation at the outlet and the cumulative oil production 2) Based on the above relational expression, combined with the exponential relational expression of relative permeability of oil and gas in the gas drive reservoir and Darcy's law, establish the relational expression of the gas drive characteristic curve of the gas drive reservoir; 3) According to the actual cumulative gas and oil production data of the reservoir, use the gas drive characteristic curve relational expression of the gas drive reservoir in step 2) to perform fitting, and obtain the coefficient items in the gas drive characteristic curve relational expression of the gas drive reservoir ; 4) Deriving and establishing the gas-oil ratio rising rate expression of the gas injection development reservoir based on the relational expression in step 2), and using each coefficient item obtained in step 3), the gas-oil ratio rising rate chart of the gas injection development reservoir is obtained. The invention can be widely used in the determination of the rising law of the gas-oil ratio in the gas injection development reservoir in the field of oilfield development research.

Description

Technical field [0001] The present invention relates to an annihable development of oil ratio increase rate characterization method, which belongs to the technical field of oil and gas field development reservoir project. Background technique [0002] Inspiration drive development is an effective development method of improving reservoir development, but when the injection of gas is broken, the production of well gas oil is often a rapid increase in rapid increase, resulting in a quick reduction of single well production, and high-efficiency to the reservoir Come challenge. In order to maximize the development effect of the air intake development reservoir, it is necessary to clearly inject the gas oil than the rising law, and guide the injection optimization of the injection of gas. However, there have been no research methods for reservoir engineering of oil ratio of oil-free development of oil ratio of oil ratio, often using reservoir numerical simulation methods to describe g...

AI Technical Summary

Problems solved by technology

However, there is no reservoir engineering theoretical research method on the gas-oil ratio increase rate of gas development reservoirs, and reservoir numerical simulation methods are often used to describe the gas-oil ratio increase law after gas injection breakthrough

However, the research period of this method is long, and the calculation accuracy is limited by the quality of the actual reservoir dynamic and static data and the matching effect of the reservoir history. The low quality of the reservoir static data or the insufficient amount of data will make it difficult to accurately represent the geological understanding. Reservoir history matching brings great uncertainty, and the quality of test data and human experience of history matching will also affect the reliability of history matching

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