Preparation method of temperature and salt tolerance inverse emulsion drag reducing agent

Abstract

The invention relates to a preparation method of a temperature and salt tolerance inverse emulsion drag reducing agent. Meanwhile, by feeding a third monomer and an initiator separately to control change of the polymerization temperature, the phenomenon that due to implosion and chain transfer which occur in the polymerization process, the molecular weight is low is prevented. A large number of sulfonic acid groups are introduced through high temperature modification, the residual monomer content is greatly decreased, better temperature and salt tolerance performance is achieved, and damage to underground strata and underground water is reduced. By using a compound emulsifier polyisobutylene succinic anhydride copolymer diethanolamine salt and methyl glucose sesquistearate, the effect of long-term storage stability of an inverse emulsion under the conditions of high molecular weight and the large number of sulfonic acid groups is achieved. Finally, the drag reducing agent of an anionic modified acrylamide inverse emulsion which has the molecular weight being not less than 15,000,000 and the tolerable temperature reaching up to 200 DEG C and still keeps the high drag reduction efficiency under the hypersalinity condition, the residual monomer content is far below 0.01%, the emulsion system is stable, and no delamination occurs after placing is performed for 12 months.

Description

technical field [0001] The invention belongs to the technical field of oil field chemistry, and in particular relates to a preparation method of a temperature-resistant and salt-resistant inverse emulsion drag reducer. Background technique [0002] The slick water system can greatly reduce the friction and pressure of fracturing construction, reduce the load of fracturing construction equipment, effectively increase the net pressure of construction, and greatly improve the effect of fracturing reconstruction. One of the most commonly used liquids. 98.0% to 99.5% of slick water fracturing fluid is sand mixing water, and additives generally account for 0.5% to 2.0% of the total volume of slick water, including drag reducers, surfactants, scale inhibitors, clay stabilizers and fungicides, etc. . The drag reducer is the most important additive in the slick water system, so the synthesis of the drag reducer is the key to the slick water system. The addition of the drag reducer ...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problem that current drag reducing agent products are applied to fracturing flowback fluid containing divalent metal ions, karst cave water, underground produced water, etc., the drag reducing effect is not good, and the drag reducing function of the drag reducing agent is reduced at high temperature, the present invention The purpose is to provide a method for preparing a temperature-resistant and salt-resistant inverse emulsion drag reducer. A modified polyacrylamide emulsion type drag reducer is synthesized by inverse emulsion polymerization. By introducing a third monomer and a modification process , so that the inverse emulsion drag reducer has good temperature and salt resistance