Preparation method of salt-tolerant soluble drag reducer

Abstract

The invention discloses a preparation method of a salt-tolerant soluble drag reducer. The preparation method comprises the following steps: (1) dissolving sorbitan mo-nooleate in white oil, performingpreparation to form a continuous phase; (2) sequentially dissolving acrylic acid, 2-acrylamido-2-methylpropane sulfonic acid, acrylamide and sorbitan mo-nooleate polyoxyethylene ether in deionized water, adjusting the pH value of a system to be 7.5-9 by a sodium hydroxide adjusting system, and performing preparation to form a dispersion phase; and (3) in a mixing state, dripping the dispersion phase into the continuous phase, after finish of dripping, pumping in nitrogen, then adding an initiator, and performing a thermostatic reaction at 30-40 DEG C. The polymer drag reducer prepared throughinverse emulsion polymerization is good in drag reducing effect, excellent in salt tolerance and high in dissolution speed, restrictions of low dissolution speed, high adding amount and low drag reducing rate are broken through, and significance is achieved on lowering the fracturing construction cost and saving fresh water resource.

Description

technical field [0001] The invention belongs to the technical field of drag reducers, and in particular relates to a preparation method of a salt-tolerant instant drag reducer. Background technique [0002] In recent years, with the discovery of shale gas reservoirs and people's emphasis on shale gas exploitation, the drag-reducing water fracturing technology for mining unconventional reservoirs with ultra-low porosity and ultra-low permeability has been popularized and applied. Drag reducer is the core additive in the drag reducing water fracturing fluid system, and its performance determines the application range of the entire system. At present, emulsion polyacrylamide is mainly used in foreign countries. There are not many domestic suppliers of drag reducer, and drag reducer with good performance Most rely on foreign imports, increasing mining costs. [0003] The drag reducer prepared by inverse emulsion polymerization has the characteristics of high relative molecular ...

AI Technical Summary

Problems solved by technology

[0004] The current relative molecular mass is greater than 1000×10 4 , The drag reduction rate is greater than 70% and the inverse emulsion polymer drag reducer with good salt resistance is less; although some literature reports in the prior art, there are poor drag reduction effect, poor salt tolerance, and high dosage , the disadvantage of poor economy