Clean steering acid fluid system containing erucyl alkyl quaternary ammonium salt surfactant

Abstract

The invention aims to provide a clean steering acid fluid system with relatively low cost and high temperature resistance and high pressure resistance. In order to solve the technical problem, the clean steering acid fluid system is realized through the following technical scheme: the clean steering acid fluid system containing an erucyl alkyl quaternary ammonium salt surfactant comprises the erucyl alkyl quaternary ammonium salt surfactant, an acid fluid consisting of at least one inorganic acid or organic acid, a ferrous stability and a corrosion inhibitor. The erucyl alkyl quaternary ammonium salt surfactant is a surfactant with low molecular viscoelasticity, is free of residue or formation of filter cake, and is little in pollution to stratum, and the flow conductivity of cracks can be effectively improved. A gel breaker (for gel breaking when encountering oil or water) is not needed, the gel breaking is thorough, and residual liquid is extremely easy to discharge. The friction drag is low and is just 30% to 40% of water, the construction displacement selectivity range is large, and the requirement of different technology improvements can be realized. The system has good de-filtration characteristic and retarding performance, and the lengths of acid etching cracks can be greatly increased.

Description

technical field [0001] The invention relates to the technical field of acid fracturing stimulation operations in oil and gas fields, in particular to a clean diverting acid solution system containing erucic acid-based alkyl quaternary ammonium salt surfactants for acid fracturing stimulation operations in high-temperature and high-pressure formations. Background technique [0002] Acid fracturing is to use acid liquid as fracturing fluid at a pressure higher than the fracture pressure of the formation, and perform fracturing without proppant. During the acid fracturing process, the wall of the fracture is eroded into an uneven surface by the dissolution of the acid liquid, so that the wall of the fracture will not be completely closed after the pump is stopped and the pressure is relieved. Ability, the effect is obvious. [0003] Acidizing can effectively remove the pollution and clogging of oil layers near the wellbore, improve the connectivity between the wellbore and the...

AI Technical Summary

Problems solved by technology

In reservoirs with strong heterogeneity, most of the acid liquid enters the medium and high permeability layers, and only a small amount of acid liquid or even no acid liquid enters the low permeability layer, which not only makes it difficult to achieve uniform acidification of the reservoir and increase oil well productivity On the contrary, it will further enhance the heterogeneity of the reservoir and increase the difficulty of mining

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