Apparent Permeability Interpretation Method and System for Low Permeability Reservoir in Formation

Abstract

The invention discloses a method and system for interpreting the apparent permeability of low-permeability reservoirs in formations. Firstly, the curve of the permeability measurement value of the test sample as a function of gas pressure is determined, and then the Knudsen number of the test sample under different pressures is determined. The curve of the permeability measurement value of the test sample changing with the gas pressure is converted into the curve of the permeability measurement value of the test sample changing with the Knudsen number, and the curve of the permeability measurement value of the test sample changing with the Knudsen number Square method data fitting, determine the intrinsic permeability of the test sample, the wall influence parameters of the test sample, and the ratio of the slip distance of the test sample to the molecular mean free path, when determining the apparent permeability of the low-permeability reservoir in the formation , using the wall influence parameter of the test sample and the ratio of the test sample’s slip distance to the molecular mean free path to correct the wall slip effect, so as to more accurately explain the apparent permeability of low-permeability reservoirs in the formation.

Description

technical field [0001] The invention belongs to the technical field of reservoir development, and in particular relates to an interpretation method and system for apparent permeability of low-permeability reservoirs in formations. Background technique [0002] At present, one of the important methods for understanding and modeling oil and gas reservoirs in low-permeability reservoirs (such as tight core or shale) in the formation is to conduct core testing, and core permeability testing is to understand the flow capacity of the reservoir. , and the most basic and most important analysis and testing means for reservoir evaluation. [0003] According to the different fluids used, the permeability test methods can be divided into liquid permeability test and gas permeability test. At present, gas permeability measurement is mostly used for low permeability reservoirs. The testing principle of permeability is usually based on Darcy's law, that is, the flow rate of porous media ...

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Problems solved by technology

[0005] However, the applicant found that the accuracy of the apparent permeability of low-permeability reservoirs determined based on existing methods is low, which will have adverse effects on subsequent reservoir evaluation and development

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