Well section method for viscous oil edge and bottom water reservoir multi-turn CO2 huff and puff

Abstract

The invention provides a well section method for multi-turn CO2 huff and puff of a viscous oil edge and bottom water reservoir. The well selection method includes the following steps: using a hull and puff oil gain amount as an evaluation index, determining a geological factor, a fluidity factor and a development factor of an oil well; imparting weight to each factor, and correcting the weight of each factor by conducting numerical value dedoublement; using a single-factor sequencing method to acquire a single-sequence matrix; on the basis of respective corrected weight of each factor and the single-sequence matrix, acquiring an overall sequence, obtaining the evidence for well selection. According to the invention, the method herein can overcome man-made interference brought by incomprehensive on-site material and uncertainty of the result from the well selection caused by difficulty of representing continuation-type variant factors, has actual significance for well selection for multi-turn CO2 huff and puff of a viscous oil edge and bottom water reservoir, and is efficient, reasonable and scientific.

Description

technical field [0001] The invention relates to a well selection method, in particular to a multi-round CO 2 The well selection method of huff and puff belongs to the technical field of petroleum exploitation. Background technique [0002] In the development process of heavy oil reservoirs with edge and bottom water, the water cut rises rapidly due to the high oil-water mobility ratio, and the degree of crude oil recovery is low. Production practice proves that CO 2 Huff and puff has good functions of water control, viscosity reduction and production increase. Affected by comprehensive factors such as geology, fluids, and development, CO 2 The throughput decision requires a scientific and effective well selection method. [0003] Conventional well selection methods mainly adopt hierarchical analysis or weight analysis, and these methods have certain application limitations. On the one hand, relying on subjective experience to establish a judgment matrix is ​​greatly aff...

AI Technical Summary

Problems solved by technology

On the one hand, relying on subjective experience to establish a judgment matrix is ​​greatly affected by human factors; on the other hand, the prerequisite for the use of conventional analysis methods is that there should not be too many influencing factors participating in the analysis, usually no more than 9

For heavy oil reservoirs with edge and bottom water, multiple rounds of CO 2 Throughput and many influencing factors are its most prominent features. Obviously, conventional analysis methods are no longer applicable

In addition, there are many continuous variables in the influencing factors, which lead to the increase of the complexity of well selection and the inconsistency of the judgment matrix.

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