A damage evaluation method for working fluid in fractured tight reservoirs that takes into account both foundation blocks and fracture systems

Abstract

The invention relates to the field of reservoir protection for tight reservoirs in the oil and natural gas industry, and provides a fractured tight reservoir working fluid damage evaluation method that takes into account both base blocks and fracture systems. By sealing the fracture part of the end face of the core plunger, the test fluid first passes through the base block and then enters the fracture, simulating the multi-scale mass transfer path in the process of oil and gas production in fractured tight reservoirs, through a single cycle of working fluid , which can measure the comprehensive damage degree of the base block and fractures in the core plunger after the action of the working fluid and the damage ratio of the matrix and fractures, so that the reservoir protection materials added to the working fluid are more targeted. The invention is easy to operate, can effectively solve the current problem of working fluid damage evaluation in fractured tight reservoirs, and has great significance for the optimization of tight reservoir protection reservoir working fluid systems and the efficient development of oil and gas reservoirs.

Description

technical field [0001] The invention relates to the field of reservoir protection of tight reservoirs, in particular to an experimental evaluation method for fractured tight reservoir damage. Background technique [0002] In terms of proven reserves and technical strength, tight oil and gas reservoirs are of great practical significance for exploration and development. Its characteristics of low porosity and low permeability, small pore throats, high capillary pressure, rich and diverse clay minerals, and local ultra-low initial water saturation make it difficult to produce oil and gas in tight reservoirs, and tight reservoirs with natural fractures often lead to oil and gas production. The output process has become more complex, there is a very high risk of damage, and if it is damaged, the degree of damage is generally high. Therefore, it is of great significance to accurately evaluate the damage degree of working fluid in fractured tight reservoirs for the economical and...

AI Technical Summary

Problems solved by technology

However, this method can only evaluate the overall damage of the rock sample including fractures and base blocks, but cannot clearly point out how much the base blocks and cracks have played in the damage process of the working fluid, and how much each accounted for. Determine whether the formula added to the working fluid to reduce the damage of the working fluid mainly affects the fractures or the matrix of the rock sample. In addition, this method considers the multi-scale path of oil and gas production in fractured tight reservoirs, and cannot simulate Comprehensive damage process of base block and fracture in formation

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