Anti-high temperature shearing agent for solid-free drilling fluid and preparation method thereof

Abstract

The invention discloses a high temperature resistant rheological modifier for a solid-free drilling fluid and a preparation method of the high temperature resistant rheological modifier. According to the rheological modifier, three monomers with different functional groups are polymerized under the condition of a redox system through the reasonable molecular design, molecular chains of a correspondingly generated polymer is fully extended and mutually act in the space to form a space net structure, other assistants mutually matched with the polymer are also used, so that the prepared rheological modifier has the shearing dilutability similar to that of a biopolymer and effectively resists high temperature and salinity, the highest tolerable temperature is up to 170 DEG C, and the rheological modifier is an efficient rheological modifier suitable for fresh water and saline water solid-free drilling fluid system; in addition, the preparation method of the rheological modifier is simple and feasible, the cost is also lower than that of the foreign like product, and the rheological modifier is quite favorable for market popularization and application.

Description

technical field [0001] The invention relates to the technical field of oil, natural gas and coalbed methane drilling operations, in particular to a high-temperature anti-shearing agent for solid-free drilling fluid and a preparation method thereof. Background technique [0002] With the development of the petroleum industry, the number of deep and ultra-deep wells is increasing, which poses new challenges to the temperature and salt resistance of drilling fluids, especially at present more and more deep horizontal wells exceeding 4000m or even 5000m. For hole purification, sand carrying and effective reservoir protection, solid-free drilling fluid with fine particles and less solid phase is often used. The cutting agent is the core treatment agent of solid-free drilling fluid. [0003] At present, the most commonly used cutting agent for drilling fluids is biopolymers, such as xanthan gum, but biopolymers have relatively poor temperature resistance in clear water, and the h...

AI Technical Summary

Problems solved by technology

[0003] At present, the most commonly used cutting agent for drilling fluids is biopolymers, such as xanthan gum, but biopolymers have relatively poor temperature resistance in clear water, and the highest temperature resistance in brine systems does not exceed 148 °C, and under high temperature conditions, The biopolymer will be hydrolyzed and the molecular chain will be broken, resulting in a significant decline in the performance of the treatment agent

Foreign countries have carried out a lot of research on drilling fluid anti-high temperature shearing agents, especially in the aspect of replacing xanthan gum. Although many companies claim that they can replace xanthan gum in the high temperature field, they really achieve similar rheological properties to xanthan gum. There are still very few treatment agents, especially the field application reports are even less

There are few domestic reports on the development of high-temperature anti-shearing agents, mainly based on natural polymers, through chemical modification to improve their temperature resistance, but on the one hand, the goal of reducing costs has not been achieved through chemical modification, on the other hand , the temperature resistance of natural polymers after modification is still limited, and a bottleneck has been encountered

[0004] Therefore, there is an urgent need to develop a shear thinning agent that not only has the shear thinning properties similar to biopolymers, but also can effectively resist high temperature and salt, so as to meet the needs of deep well drilling fluids and solve the problem of high temperature and easy hydrolysis of current biopolymer treatment agents. and the problem of poor temperature resistance

Images