Supramolecular multi-copolymer type clean fracturing fluid

Abstract

The invention discloses a supramolecular multi-copolymer type clean fracturing fluid. The supramolecular multi-copolymer type clean fracturing fluid comprises the following components in percentage by mass: 0.3-1.0% of supramolecular active polymer, 0.3-1.0% of cross-linking agent, 1-2% of KCL and 96-98% of water, wherein the molecular formula of the supramolecular active polymer is shown in the specification, R is C13-C21 straight chain or branched chain alkyl, n is an integer of 3-6 and p is an integer of 2-4. The fracturing fluid disclosed by the invention has the characteristics of high-temperature resistance, safety and environmental friendliness.

Description

technical field [0001] The invention relates to a supramolecular multiple copolymer type clean fracturing fluid, which belongs to the technical field of oil field fracturing. Background technique [0002] At present, domestic oilfield hydraulic fracturing construction basically adopts polymer fracturing fluid technology, that is, guar gum and its derivatives used in water-based polymer fracturing fluid. It has been used in fracturing fluids for many years because of its good rheology control properties. It has many advantages such as good shear resistance, good thermal stability, and strong ability to control fluid loss, and is widely used at home and abroad. However, like many other water-based fracturing fluids, hydroxypropyl guar gum (HPGF) still has inevitable defects: first, it cannot quickly swell and hydrate, and the dissolution rate is slow, so it is difficult to solve the problem of construction scale and rapid gel breaking and return. The contradiction between th...

AI Technical Summary

Problems solved by technology

However, like many other water-based fracturing fluids, hydroxypropyl guar gum (HPGF) still has inevitable defects: first, it cannot quickly swell and hydrate, and the dissolution rate is slow, so it is difficult to solve the problem of construction scale and rapid gel breaking and return. The contradiction between the performance requirements of the fracturing fluid is eliminated; the second is that the vegetable glue fracturing fluid often has a lot of residue after the gel is broken, which is easy to block the filling layer of the fracture, causing secondary damage and affecting the fracturing effect; the third is that the plant glue Natural polymers such as gelatin cellulose have poor temperature resistance and are easy to biodegrade. They can only be prepared and used immediately, and the raw materials depend on imports, which largely limits their application.

However, the disadvantage of this clean fracturing fluid is that it has poor high temperature resistance, and generally can only meet the well construction requirements below 80°C.

The filtration loss in the formation is serious, and the cost is high, which also limits its wide application

Some clean fracturing fluids can withstand 150°C for a short time, but the stability becomes poor after long-term shearing

In addition, there are also the defects of large dosage and high cost, so it is difficult to popularize

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