CEMENT COMPOSITIONS AND METHODS Russian patent published in 2023 - IPC E21B33/138 E21B33/14 C09K8/467 

FIELD: cement systems

SUBSTANCE: group of inventions relates to cement systems that are in contact with drilling fluids in an underground well. The method of cementing an underground well includes obtaining a cement slurry containing water, hydraulic cement and oil-absorbing material particles. In this case, the particles are present in a sufficient amount to interact with the non-aqueous component of the drilling fluid in order to change the properties of the drilling fluid in the underground well. The cement slurry is placed in an underground well. After the cement slurry is placed in the subterranean well, the oil-absorbing material particles are brought into contact with the non-aqueous drilling fluid component, thereby allowing the non-aqueous drilling fluid component to resist the flow of the drilling fluid. Moreover, these oil-absorbing particles can be oblong, fibrous, cylindrical or asymmetric. The aspect ratio of the particles is from 1.1 to 2000 before swelling and from 2.2 to 3500 after swelling.

EFFECT: improvement of the zonal isolation by reducing the fluidity of the drilling fluid.

20 cl, 7 dwg, 6 tbl, 3 ex