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

Abstract

The invention provides a well section method for multi-turn CO2 huff and puff of a viscous oil edge and bottom water reservoir based on water content. The well selection method includes the following steps: computing and correcting respective factor weight with well opening water content after huff-puff as an evaluation index; using a single-factor sequencing method to acquire a single-sequence matrix; on the basis of respective corrected factor weight and the single-sequence matrix, acquiring an overall sequence; on the basis of the result of the overall sequence and in combination with the on-site reality, 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 present invention relates to a well selection method, in particular to a multi-cycle 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, and the degree of crude oil recovery is low. by CO 2 Huff and puff measures can reduce the viscosity of crude oil, inhibit the rise of water cut, and improve the ultimate recovery of oil reservoirs. Through production practice and numerical simulation research, it is found that the water cut of the well after huffing and puffing not only directly reflects the CO 2 The degree of water control after throughput has a greater impact on the final increase in throughput. Therefore, compared with the increase in oil production by huff and puff, the evaluation index of water cut after huff and puff can comprehensively reflect the...

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 Due to the large number of influencing factors, the conventional analysis method is no longer applicable; and there are many continuous variables in the influencing factors, which leads to the increase of the complexity of well selection and the inconsistency of the judgment matrix and other problems

[0004] The reason is that the conventional method does not consider the impact of incomplete field data on the weight distribution, so the establishment of the judgment matrix is ​​greatly affected by human factors

On the other hand, there is no distinction between the impact of continuous variables and discontinuous variables in each factor on the judgment matrix, resulting in inconsistent judgment matrices

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