A kind of carboxymethyl guar gum crosslinking agent and its preparation method and application

Abstract

The invention discloses a carboxymethyl guar gum cross-linking agent and a preparation method and application thereof. The technical scheme is characterized in that the carboxymethyl guar gum cross-linking agent comprises the following raw materials in percentage by weight: 8-12% of crystalline aluminum chloride, 20%-22% of additives and the balance of water, wherein the additives are at least two of formaldehyde, glyoxal, ethanediol, propanetriol and glacial acetic acid. The invention also discloses the preparation method of the carboxymethyl guar gum cross-linking agent and the application of the carboxymethyl guar gum cross-linking agent in a carboxymethyl guar gum fracturing fluid system. The carboxymethyl guar gum cross-linking agent prepared through the method disclosed by the invention has the advantages of wide applicability, good cross-linking property and low integrated cost; after added with the carboxymethyl guar gum cross-linking agent, the carboxymethyl guar gum fracturing fluid system becomes weakly acidic and has a pH value of 3-4, and has the functions of effectively inhibiting the expansion migration caused by the electronegativity of a clay surface, thus playing a role in stabilizing clay.

Description

technical field [0001] The invention belongs to the technical field of oilfield chemical carboxymethyl guar gum fracturing fluid, and in particular relates to a carboxymethyl guar gum crosslinking agent and a preparation method and application thereof. Background technique [0002] Due to complex lithology, poor physical properties, shale content, high reservoir permeability and low permeability of oil and gas reservoirs, conventional water-based fracturing fluids such as guar gum or hydroxypropyl guar gum fracturing fluids are used to stimulate the reservoirs. There are disadvantages such as high amount of thickening agent, high water insoluble matter, high content of gel-breaking fluid residue, and great damage to reservoir and fracture conductivity, which seriously affect the effect of fracturing. In order to further improve the effect of reservoir fracturing, the development and application of carboxymethyl guar gum fracturing fluid technology, compared with conventional...

AI Technical Summary

Problems solved by technology

[0003] At present, the commonly used cross-linking agents for guar gum fracturing fluid systems in China are mainly inorganic or organic boron, organic zirconium, and organic titanium. These cross-linking agents are either cross-linked under alkaline conditions, such as boron cross-linking agents , it is easy to block the channel, causing serious secondary damage; or there is a characteristic of high cross-linking cost, such as organic zirconium, organic titanium