Slick water fracturing fluid for medium-high temperature compact reservoir and preparation method thereof

Abstract

The invention belongs to the technical field of oil field stimulation, and particularly relates to a slick water fracturing fluid for medium-high temperature compact reservoirs and a preparation method thereof. The slick water fracturing fluid comprises the following components in percentage by weight: 0.30 to 0.45 percent of a thickening agent, 0.03 to 0.05 percent of a clay stabilizer, 0.20 to 0.50 percent of a structural stabilizer, 0.01 to 0.05 percent of a strength maintaining agent, 0.04 to 0.10 percent of a temperature resistant regulator, 0.05 to 0.10 percent of a gel breaker degradingagent and the balance of water. The slick water fracturing fluid has fast dissolution. In 30 seconds, 80% of the final viscosity increase can be achieved, the drag reduction rate can reach more than80%, the core damage rate is less than 10%, well temperature resistance and shear resistance can be satisfied under the medium and high temperature conditions of 90 deg c to 180 deg c, the sand carrying concentration can meet the construction requirements of more than 750 kg / m<3>, the gel breaking is complete, the drainage rate can reach more than 40%, and after simple sand settling treatment, theslick water fracturing fluid can be reused for more than 20 times to maintain more than 90% of the original performance.

Description

technical field [0001] The invention belongs to the technical field of oilfield stimulation, in particular to a slickwater fracturing fluid for medium-high temperature tight reservoirs and a preparation method thereof. Background technique [0002] Fracturing, as the main stimulation measure of oil and gas reservoirs, has been developed rapidly and widely used. Fracturing is the use of pressure to open formations to form fractures and support them with proppant to reduce fluid flow resistance and increase production and injection measures. The purpose of fracturing is to form fractures with conductivity in the formation. The fracturing fluid used determines the fracturing effect to a large extent. At the same time, there are certain requirements for the viscosity of the fracturing fluid so that it can Fluids known as low viscosity flow back easily to avoid damage to hydrocarbon layers in the formation. [0003] The most commonly used fracturing fluids at home and abroad ar...

AI Technical Summary

Problems solved by technology

However, guar gum and its modified products have the inherent disadvantages of easy corruption of vegetable gum, and the composition of the fracturing fluid system is complex. The formation of jelly depends on chemical cross-linking. It is difficult and costly to treat the flowback fluid after gel breaking, and it is feasible to reuse it. poor sex

Since the above defects of plant gum fracturing fluids such as guar gum can neither alleviate the pressure of environmental protection nor meet the above-mentioned on-site construction requirements, polymer fracturing fluids are widely used to solve the above problems

[0004] At present, there are many kinds of acrylamide polymer thickeners, among which the thickeners of guar gum and its derivatives are the most widely used, but there are common problems such as incomplete gel breaking, easy gel return, and high residue content of gel breaking liquid. The problem is that it is easy to cause blockage damage, resulting in a decrease in matrix permeability and fracture conductivity, thereby affecting the fracturing effect. At the same time, the friction of vegetable gum fracturing fluid pipelines is high, resulting in higher wellhead pressure at the same displacement, resulting in More hydraulic power loss and higher construction risk

Synthetic polymer thickeners mainly include polyacrylamide, sodium polyacrylate, polyacrylate and polyvinyl alcohol, etc., which generally have the characteristics of strong thickening ability, good gel breaking performance, and less residue, but the cost is generally high. Use the site to promote the application

At the same time, due to the high temperature of medium-high temperature reservoirs, the polymer fracturing fluid has poor temperature and shear resistance and sand-carrying performance under high-temperature conditions, which cannot meet the construction needs of high-sand concentration stages on site.

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