Preparation technology of coated material

Abstract

The invention belongs to the field of mixtures for pore drilling or well drilling, and concretely discloses a preparation technology of a coated material. The preparation technology comprises the following steps: (1) preparation of the following raw materials: aggregates, outer layer polyol resin, inner layer polyol resin, inner layer isocyanate resin, outer layer isocyanate resin, an outer layercatalyst, an inner layer catalyst and an amine additive, wherein the hydroxyl equivalent of the polyol resin is 60-300 , and the mass part 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 discharging. The above proppant prepared by the preparation technology can naturally suspend in clearwater, and does not need to add any thickener in the fracturing process while meeting the fracturing index of conventional proppants, so the fracturing cost is reduced, the fracturing process is simplified, and the environmental pollution is reduced.

Description

technical field [0001] The invention relates to the field of a mixture used for drilling or well drilling, in particular to a preparation process of a coating material. Background technique [0002] Hydraulic fracturing is a widely used oil and gas well stimulation measure. Hydraulic fracturing is currently the main form of natural gas extraction. It requires that a large amount of water mixed with chemicals be injected into shale formations for hydraulic fracturing to release natural gas. [0003] Hydraulic fracturing technology has been relatively mature at home and abroad. Petroleum fracturing proppant is one of the essential items in the fracturing process in China. Its performance will directly affect the hydraulic fracturing effect. The apparent density is the key to evaluate the performance of proppant. One of the important indicators, the lower the apparent density, the lower its relative density relative to the fracturing fluid. When the proppant is mixed with the f...

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.

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