Reactive polymer for well drilling plugging and preparation method thereof

Abstract

The invention discloses a reactive polymer for well drilling plugging and a preparation method thereof. The polymer is mainly prepared by polymerizing the following raw materials in percentage by mass: 59-85% of first raw material, 14-40% of second raw material, 0.01-0.5% of initiator and 0.01-0.5% of reducer. The first raw material is one or mixture of more than two of acrylamide, acrylic acid and sodium acrylate. The second raw material is one or mixture of more than two of vinyl acetate, hydroxyethyl methacrylate and 2-hydroxyethyl acrylate. The method comprises the following steps: 1. preparing the raw materials and a solvent water; 2. after dissolving the first raw material, adding the second raw material; 3. adding the initiator, and continuously introducing nitrogen into the mixed solution to remove oxygen in the mixed solution; 4. in a nitrogen atmosphere, adding a reducer, heating the mixed solution to 20-40 DEG C, and carrying out polymerization reaction to obtain a jelly; and 5. drying the jelly, and pulverizing to obtain the polymer.

Description

technical field [0001] The invention relates to a polymer, in particular to a reactive polymer for oil and gas field drilling and plugging, and a preparation method of the polymer. Background technique [0002] Lost circulation is a complex problem in drilling operations. It causes drilling fluid to leak from the wellbore into the lost channel, which not only consumes a lot of mud and plugging materials, but also may cause well collapse, pipe sticking, blowout, and even lead to the scrapping of the wellbore, etc. Major accidents cause huge economic losses. Therefore, the plugging material is an indispensable substance in the process of leak prevention and plugging in drilling operations, and its performance will directly affect the success rate of plugging construction. [0003] In the 1960s, the country began to apply the plugging material to deal with lost circulation, and carried out some basic research work. During the entire period before the 1970s, high-viscosity dri...

AI Technical Summary

Problems solved by technology

During the entire period before the 1970s, high-viscosity drilling fluid plus bridge plugging materials (sawdust, mica, straw, mud balls, bricks, etc.) and cement plugs were mainly used. The plugging materials and methods were single, often resulting in Failure of lost circulation treatment

However, these existing lost circulation plugging materials usually have components separated from each other, unable to provide synergistic effect, and expansion plugging agent has small water expansion, and the plugging agent is not easy to stay stably under external force. Medium technical problems in the leakage layer, which may easily lead to poor plugging effect and repeated leakage after plugging

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