High-pressure-bearing free-crosslinking supermolecule composite gel leaking plugging agent and preparation method thereof

Abstract

The invention provides a high-pressure-bearing free-crosslinking supermolecule composite gel leaking plugging agent and a preparation method thereof. The gel leaking plugging agent is prepared from the following ingredients in parts by weight: 83 to 90 parts of nonionic monomers, 2 to 4 parts of anionic monomers, 7 to 10 parts of cationic monomers, 1 to 3 parts of biological polysaccharide and 0.001 to 0.005 part of initiating agents. The preparation method comprises the steps that the anionic monomers are put into a three-neck round-bottom flask containing water; the pH is regulated; then, the nonionic monomers are added; after uniform stirring is performed, the initiating agents are added; heating reaction is performed under the sealed condition; then, the cationic monomers are added; reaction is continuously performed; cutting up, drying and pulverization are performed to obtain white solid powder; the biological polysaccharide and the white solid powder are uniformly mixed to obtain the target product. The high-pressure-bearing free-crosslinking supermolecule composite gel leaking plugging agent has the advantages that the leaking plugging agent prepared after dissolution in water forms a continuous space net rack structure; the pressure bearing capability and the intensity of the leaking plugging agent are improved; repeated loss cannot easily occur.

Description

technical field [0001] The invention belongs to the technical field of petroleum exploitation, and in particular relates to a high-pressure non-crosslinked supramolecular composite gel plugging agent and a preparation method thereof. Background technique [0002] Gel plugging agent is a high-performance drilling plugging agent developed in recent years. Compared with traditional plugging agents, gel plugging agent has strong continuity and strong deformability, and can well match formation fractures, porosity and even Lost layers such as karst caves have strong retention capacity. At present, the gel plugging agent is mainly composed of a water-soluble polymer compounded crosslinking agent, and can also be compounded with cement slurry and bridge plug particles. However, the cross-linked gel plugging agent itself also has certain disadvantages: on the one hand, the cross-linking agent has limited cross-linking effect on the gel plugging polymer, and it is difficult to form ...

AI Technical Summary

Problems solved by technology

However, the cross-linked gel plugging agent itself also has certain disadvantages: on the one hand, the cross-linking agent has limited cross-linking effect on the gel plugging polymer, and it is difficult to form a continuous space network structure, which leads to gel plugging The strength of the agent is not high, and the pressure bearing capacity is low; on the other hand, the crosslinking effect of the crosslinking agent on the gel polymer is easily affected by external conditions such as temperature, pH value and other factors, which makes it difficult to control during on-site construction. Gelling time and gelling strength of gel plugging agent