Coated sand for sand prevention in oil well and preparation method of coated sand

Abstract

The invention discloses coated sand for sand prevention in an oil well and a preparation method of coated sand. The coated sand comprises A-type coated sand and B-type coated sand and is characterized in that the A-type coated sand is obtained by wrapping quartz sand with organosilicon-modified epoxy resin, a ketimine curing agent and external isolating agent hydroxy methyl cellulose in sequence; B-type coated sand is obtained by wrapping the surface of the quartz sand with cycloaliphatic epoxide resin, an amine curing agent and external isolating agent hydroxy methyl cellulose in sequence. The coated sand disclosed by the invention comprises the A-type coated sand and B-type coated sand, and a co-synergistic effect is generated after the A-type coated sand and the B-type coated sand are mixed, so that the requirements for low-temperature curing and high-temperature mining are met simultaneously. The coated sand disclosed by the invention meets the actual application requirements, gives consideration to low-temperature curing (a minimum temperature of 40 DEG C) to form higher strength, simultaneously is good in permeability, can stably work in a high temperature-resistant environment (about 280 DEG C), is wide in research and development scope of application, can be suitable for not only heavy oil wells, but also middle and low-temperature oil wells and water wells and is lower in comprehensive cost.

Description

technical field [0001] The invention belongs to the technical field of chemical sand control in petroleum exploitation, and in particular relates to coated sand for oil well sand control and a preparation method thereof. Background technique [0002] my country's unconsolidated sandstone has a large distribution range and large reserves, and its output occupies a major position. Sand production in oil wells is extremely harmful, mainly manifested as: severe abrasion of the ground and downhole equipment, and even sand jams; drastic increase in maintenance workload such as sand flushing, inspection of pumps, and ground tank cleaning; sand buried in oil layers or wellbore sand plugging will cause oil wells to stop production ; When the sand production is serious, it will also cause the well wall or even the oil layer to collapse and damage the casing or even cause the oil well to be scrapped. These hazards have not only increased the production cost of crude oil, but also incr...

AI Technical Summary

Problems solved by technology

The sand control of this kind of oil wells currently adopts mechanical sand control with poor prognosis. Once the secondary sand control measures are blocked by fine sand, the casing pipe needs to be pulled out and replaced again. increased cost of

In the production of heavy oil wells, the artificial formation formed by sand control must meet the requirements of steam huff and puff thermal recovery, while the current chemical sand control cannot be used because it cannot meet the requirements of low-temperature solidification and high-temperature production. The defects of poor permeability, insufficient curing strength at low well temperature, and poor temperature resistance exist in the application of single-component coated sand and double-component coated sand.

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