Rheological stabilizer for synthetic base drilling fluid and preparation method thereof

Abstract

The invention discloses a rheological stabilizer for a synthetic base drilling fluid and a preparation method thereof. The method comprises the following steps: in the inert atmosphere, an allyl monomer is subject to copolymerization to obtain the rheological stabilizer under the condition that both an organic solvent and an initiator exist; the allyl monomer is at least one of the unsaturated fatty acid with carboxyl, long carbon chain acrylamide and phenethylene compound. The rheological stabilizer is suitable for preparing a deepwater synthetic base drilling fluid; after the stabilizer is added, the shearing force of a drilling fluid system is less influenced by temperature change. The rheological stabilizer can solve the problems of high ECD (Equivalent Circulating Density) value, circulation loss, difficulty in pressure control and the like, which are caused by great difference between the rheology behaviors of the conventional synthetic base drilling fluid under low-temperature and high-temperature conditions, so as to better adapt to deepwater drilling requirements. The rheological stabilizer provided by the invention has excellent compatibility with other additive for drilling fluids.

Description

technical field [0001] The invention relates to a rheological stabilizer for synthetic base drilling fluid and a preparation method thereof. Background technique [0002] The temperature changes significantly during deepwater drilling, and the rheology of the drilling fluid is greatly affected by the temperature, especially the viscosity under dynamic shear force and low shear rate is difficult to control, resulting in lost circulation and high equivalent circulating density (ECD). A series of problems such as difficult pressure control are becoming the challenges faced by deepwater drilling. Synthetic-based drilling fluid has become a common drilling fluid system for offshore oil and gas drilling because of its high rate of penetration and good wall stability. However, the viscosity and shear force of this drilling fluid are significantly affected by temperature, so lost circulation is prone to occur. , especially when the drilling fluid is left standing for a long time. ...

AI Technical Summary

Problems solved by technology

Synthetic-based drilling fluid has become a common drilling fluid system for offshore oil and gas drilling because of its high rate of penetration and good wall stability. However, the viscosity and shear force of this drilling fluid are significantly affected by temperature, so lost circulation is prone to occur. , especially when the drilling fluid is left standing for a long time

[0003] In summary, it is necessary to provide a rheological stabilizer for synthetic-based drilling fluids, so that the dynamic shear force of the synthetic-based drilling fluid system will not be affected by temperature changes, so as to solve the problem of rheological problems caused by conventional synthetic-based drilling fluids during deepwater drilling. The large difference between low temperature and high temperature causes technical problems such as high ECD value, lost circulation and pressure control

Images