DEFOAMING COMPOSITIONS Russian patent published in 2017 - IPC C08L31/08 C08L33/06 C04B28/02 C04B24/32 C04B40/00 C04B103/50 B01D19/04 

FIELD: fire safety.

SUBSTANCE: invention relates to defoaming composition, as well as a cement composition containing it, a method of reducing air entrainment in a cement composition and cementing of underground formation. Defoaming composition contains an ester of organic acid and block copolymer of ethylene oxide and propylene oxide and one or more esters of organic acids with polymers selected from organic acid ester and ethylene oxide polymer of given formula, organic acid ester and propylene oxide polymer presented by other formula and mixtures thereof. Cement composition includes hydraulic cement, water and defoaming composition. Method of reducing air entrainment in a cement composition involves adding defoaming composition to cement composition. Cementing of underground formation includes introduction into underground formation of said cement composition containing hydraulic cement, water and defoaming composition and further hardening of cement.

EFFECT: invention provides hydraulic insulation between casing pipe and cement and between cement and formation, which simultaneously prevents formation of fluid channels in a cement sheath, provides efficient foaming control.

18 cl, 4 dwg, 5 tbl, 6 ex