High-temperature-resistant saturated brine drilling fluid and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant saturated brine drilling fluid and a preparation method thereof. The drilling fluid contains 100 parts by weight of water, 2-5 parts by weight of salt resistant soil, 1-3 parts by weight of sepiolite, 10-15 parts by weight of a high temperature and salt resistant fluid loss agent, 1-2 parts of a high temperature and salt resistant diluent, 0.5-2 parts by weight of a high temperature resistant stabilizer, and 35 parts by weight of sodium chloride. The preparation method of the drilling fluid comprises the following steps: respectively adding the salt resistant oil and sepiolite to water, stirring for 20min, ageing for 24h, sequentially adding the high temperature and salt resistant fluid loss agent, the high temperature and salt resistant diluent, the high temperature resistant stabilizer and sodium chloride, and stirring under a speed of 8000r/min to obtain the drilling fluid. The materials of the drilling fluid are convenient to use, can be directly mixed with water, and is stirred for drilling. The drilling fluid has the advantages of good rheological property, strong inhibition performance, realization of the salt resistance saturation in the high temperature environment, realization of the HTHP fluid loss of below 35mL, and benefiting for the hole wall stability and the drill safety.

Description

technical field [0001] The invention relates to the field of deep continental scientific drilling, the field of geological drilling, deep oil and gas drilling, high-temperature geothermal drilling, and high-temperature-resistant brine drilling fluid for future hot-dry rock drilling and a preparation method thereof. Background technique [0002] In deep and ultra-deep well drilling, high temperature, high pressure, high pollution and other "three high" complex environments are recognized worldwide problems in deep drilling in the future, among which high temperature resistant and anti-pollution drilling fluid (drilling mud) technology is one of the core technologies. The deep continental scientific drilling wells that will be implemented in the future in my country will be more than 10,000 meters deep, and the bottom hole temperature may be as high as 350°C. The performance of the mud in a high-temperature and high-pressure environment will cause extremely serious damage. In ...

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Problems solved by technology

[0006] The technical problem to be solved by the present invention is that current high temperature resistant drilling fluids are usually only suitable for high temperatures around 200°C and cannot meet the requirements of higher temperature environments

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