High-temperature-resistant and high-salt-resistant hydrophobic blocking agent and preparation method thereof

Abstract

The invention relates to the technical field of well drilling, in particular to a high-temperature-resistant and high-salt-resistant hydrophobic blocking agent and a preparation method thereof. The high-temperature-resistant and high-salt-resistant hydrophobic blocking agent is prepared from 5 to 10 parts by mass of modified SiO2, 2 to 5 parts by mass of lauryl sodium sulfate, 10 to 20 parts by mass of acrylamide, 10 to 20 parts by mass of methacryloyloxyethyl trimethyl ammonium chloride, 2 to 6 parts by mass of octadecyl methacrylate, 0.2 to 0.5 part by mass of an initiator and a proper amount of acetone and water. According to the SiO2 graft polymer prepared through polymerization, the blocking effect is achieved through SiO2, the surface of SiO2 is hydrophobic through a long-chain alkyl chain and an ester group, and then the surface of a mud cake or a stratum pore is hydrophobic while tiny pores in the mud cake and pores in the stratum are blocked, so that invasion of water molecules is more effectively prevented, the compactness of the mud cake is improved, and the water permeability of the mud cake is improved. The filtrate loss is reduced, the filtrate loss reduction performance of the drilling fluid at high temperature and high salt is enhanced, formation pores and cracks are blocked, and the effect of efficiently stabilizing a well wall is achieved.

Description

technical field [0001] The invention relates to the technical field of drilling, in particular to a high-temperature and high-salt hydrophobic plugging agent and a preparation method thereof. Background technique [0002] With the current rapid expansion and increase of my country's demand for oil and natural gas, the degree of dependence on crude oil and natural gas has increased year by year, and new replacement oil and gas resources are urgently needed. According to the results of the second national oil and gas resource evaluation, my country's oil and gas (shale gas, oil shale, deep layers, etc.) resources have great potential for development. The efficient development of these oil and gas resources has important practical significance for improving my country's energy security level. One of the powerful measures to alleviate the pressure of my country's energy dependence on foreign countries is also a major guarantee for maintaining national energy security. The effici...

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Problems solved by technology

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