Organic aluminum-zirconium crosslinking agent and preparation method thereof, and low-molecular polymer fracturing fluid

Abstract

The invention discloses an organic aluminum-zirconium crosslinking agent and a preparation method thereof, and a low-molecular polymer fracturing fluid. The crosslinking agent is prepared by reacting the following raw materials in parts by weight: 15-25 parts of zirconium salt, 15-25 parts of aluminum salt, 150-250 parts of polyalcohol, 75-85 parts of organic acid, 15-25 parts of gluconate and 55-65 parts of water. The organic aluminum-zirconium crosslinking agent has excellent high temperature resistance, and has favorable crosslinking effect under the conditions of high temperature and high salinity. The organic aluminum-zirconium crosslinking agent is stable under the condition of low pH value, can implement acid crosslinking, and ensures the normal proceeding of the acid fracturing. The organic aluminum-zirconium crosslinking agent has favorable compatibility with polymers and high crosslinking capacity; and the fracturing fluid formed by compounding the organic aluminum-zirconium crosslinking agent with polymers has the advantages of stable gel, excellent solid carrying capacity, excellent viscosity breaking performance and excellent shearing resistance under high-temperature conditions. The organic aluminum-zirconium crosslinking agent has the characteristics of high solubility, no pollution and low damage degree to the reservoir, and has wide application prospects.

Description

technical field [0001] The invention belongs to the technical field of chemical agents for oilfields, and specifically relates to an organoaluminum-zirconium crosslinking agent, and also relates to a preparation method of the organoaluminum-zirconium crosslinking agent and a low-molecular polymer fracturing fluid using the crosslinking agent. Background technique [0002] Hydraulic fracturing is an important technical measure for increasing production of oil and gas wells and increasing injection of water wells. The purpose of fracturing is to form fractures with a certain size and conductivity in the formation, and its success is closely related to the performance of the fracturing fluid used. Hydraulic fracturing has certain requirements for the performance of fracturing fluids, such as viscosification, suspension, fluid loss, friction loss, stability, and formation damage. At present, the widely used fracturing fluid system is still water-based fracturing fluid (accounti...

AI Technical Summary

Problems solved by technology

However, common cross-linking agents such as organoboron cross-linking agents have unsatisfactory cross-linking effects on synthetic polymers, and with the long-term water injection development of oil and gas reservoirs, most formations are now alkali-sensitive formations. is becoming more and more important, and the formation alkali-sensitivity problem caused by boron cross-linking agent cannot be ignored

Others such as a single organoaluminum crosslinking agent are also used, but they are unstable at low pH values ​​and prone to hydrolysis at high temperatures and high salinity, resulting in unstable gels and greatly limited application range.

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