Preparation method of coated proppant

Abstract

The invention belongs to the field of mixtures for hole drilling or well drilling, and concretely discloses a preparation method of a coated proppant. The preparation method comprises the following steps: (1) preparation of the following raw materials: aggregates, polyol resin, epoxy resin, an epoxy resin curing agent, isocyanate resin, a catalyst and an amine additive, wherein the hydroxyl equivalent of the polyol resin is 60-300, and the mass of the isocyanate resin is 2 / 5 to 4 / 5 of the amount of the polyol resin; (2) heating; (3) sand mixing; (4) primary coating; (5) secondary coating; and(6) sand production. The proppant prepared by the preparation method can naturally suspend in clear water, and can meet the fracturing index requirement of conventional proppants without adding any thickener in the fracturing process, so the fracturing cost is reduced, the fracturing process is simplified, and the pollution to the environment is reduced.

Description

technical field [0001] The invention relates to the field of mixtures used for drilling or well drilling, in particular to a method for preparing a film-coated proppant. Background technique [0002] In order to develop deep oil and gas wells and increase production, hydraulic fracturing technology is widely used. Hydraulic fracturing technology is a technology that uses high-pressure pumps on the ground to continuously inject high-viscosity fracturing fluid into the oil well through the wellbore to form a high pressure in the lower part of the oil well. With the continuous injection of fracturing fluid, the pressure also continues to rise. When the tensile strength and formation stress of the formation rock near the wellbore wall are less than the pressure formed by the fracturing fluid, fractures will occur in the formation near the bottom of the well. When the fracturing fluid carrying proppant continues to be injected, the fractures in the rock formation will extend for...

AI Technical Summary

Problems solved by technology

[0005] The effect of the polyurethane resin used in the proppant coating is to increase the hardness of the proppant and reduce the fracture rate of the proppant, but this kind of proppant only meets the requirements of strength and hardness, and is still not self-suspending

During construction, it is still necessary to prepare a viscoelastic carrier fluid. This construction method makes fracturing costly, seriously damages the reservoir, and pollutes the environment.

Images