A kind of water base drilling fluid and preparation method thereof

Abstract

The invention discloses a water-based drilling fluid and a preparation method thereof. The water-based drilling fluid includes base slurry and modified epoxy asphalt fluid. The modified epoxy asphalt fluid includes modified epoxy asphalt particles, water, stable dispersant and stabilizer. The modified epoxy asphalt particles include epoxy asphalt The core formed and the shell formed by the modifier, in terms of parts by mass, the core is 7 to 9 parts, and the shell is 1 to 3 parts; the modifier includes polymerized sulfur and free sulfur, and the polymerized sulfur in the modifier The weight ratio to free sulfur is 3:7~7:3. The modified epoxy asphalt fluid is added to the water-based drilling fluid of the present invention, wherein the asphalt particles are a mixture of high-elastic polymeric sulfur and free sulfur coated with a layer of epoxy asphalt, which not only has a small particle size, but also has a certain Elastic deformation ability, and excellent high temperature resistance. The drilling fluid has good rheological properties and high temperature and high pressure fluid loss reduction effect when used at high temperature.

Description

technical field

[0001] The invention belongs to the technical field of petroleum drilling and production, and in particular relates to a water-based drilling fluid and a preparation method thereof. Background technique

[0002] With the development of petroleum exploration and development, the drilling depth continues to deepen, the formations encountered become more and more complex, and the number of special craft wells such as directional wells and horizontal wells is gradually increasing. This makes drilling engineering put forward higher requirements on the performance of drilling fluid, especially the ability to resist high temperature. As an important drilling fluid treatment agent, asphalt products have good comprehensive effects such as anti-slumping, lubrication, reducing fluid loss and high temperature stability. However, the general softening point bitumen cannot meet the high-temperature operation requirements in deep wells due to excessive softening or even fl...