Calibration method for oil-water relative permeability curve and oil displacing efficiency

Abstract

The invention relates to a calibration method for an oil-water relative permeability curve and an oil displacing efficiency. The calibration method comprises the following steps: 1), performing an indoor oil-water relative permeability experiment, combining basic parameters of the experiment so as to obtain experimental data of a water ratio, cumulative oil yield, cumulative water yield and the like at different sampling times, and drawing an oil-water relative permeability curve before calibration; 2), fitting the cumulative oil yield and the cumulative water yield by adopting a Zhang type water driving curve with wide adaptability, and solving recoverable reserves; 3), plugging the recoverable reserves and the basic parameters of the experiment into an expression of residual oil saturation, and solving the residual oil saturation; 4), according to the residual oil saturation and an exponential expression of a water phase relative permeability curve in the straight line form, solving water phase relative permeability corresponding to the residual oil saturation; 5), replacing the residual oil saturation and the water phase relative permeability corresponding to the residual oil saturation in the oil-water relative permeability curve before the calibration with the solved residual oil saturation and the solved water phase relative permeability corresponding to the solved residual oil saturation, so that an oil-water relative permeability curve after calibration is obtained; and 6), calibrating the oil displacing efficiency according to the solved residual oil saturation.

Description

technical field [0001] The invention relates to a calibration method of porous medium seepage research parameters, in particular to a calibration method of oil-water phase permeability curve and oil displacement efficiency. Background technique [0002] The relative permeability curve (hereinafter referred to as the relative permeability curve or relative permeability) is a dynamic characteristic parameter of the interaction between rock and fluid, and is one of the most important basic data in reservoir development. The endpoint value of the oil-water phase permeability curve determines the oil displacement efficiency of the water flooding development of the oil field, and according to the reservoir engineering theory, the ultimate recovery factor of the oil field water flooding development is equal to the product of the oil displacement efficiency and the sweep coefficient, that is, the oil-water phase permeability The shape of the curve determines the dynamic characterist...

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Problems solved by technology

The principle of this method is clear, but the centrifuge experiment needs to be carried out after the relative permeability experiment, and the same core needs to be re-washed and saturated, which is easy to cause changes in the porosity and permeability parameters of the non-cemented core, and at the same time increases the cost of the experiment and prolongs the experiment time. High requirements, high cost, long time

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