ANTIFOAMING AGENT COMPOSITION AND METHODS FOR PRODUCTION AND USE THEREOF Russian patent published in 2013 - IPC C09K8/35 C09K8/42 C09K8/58 C09K8/60 

FIELD: chemistry.

SUBSTANCE: invention relates to use of antifoaming agents in well operations. The antifoaming agent composition for well applications contains: from about 40 vol. % to about 80 vol. % distilled water and/or other types of water, from about 10 vol. % to about 30 vol. % organosilicon antifoaming agent containing 60.0 wt % water, 7.0-13.0 wt % polydimethylsiloxane and optionally 5.0 wt % methyl cellulose, and from about 10 vol. % to about 30 vol. % active organosilicon antifoaming agent containing more than 60.0 wt % water, 7.0-13.0 wt % polydimethylsiloxane, 1-5 wt % hydroxyethyl cellulose, 1-5 wt % spent amorphous silicon dioxide, 1-5 wt % mono- and diglycerides C₁₄-C₁₈, where the composition is stable at temperature of up to about 232°C. The method involves adding an effective amount of said antifoaming agent composition to a foamed fluid medium, where its amount is sufficient for complete defoaming of the foamed fluid medium, wherein the antifoaming agent composition allows repetition of foaming-defoaming cycles. The inventions are developed in subclaims.

EFFECT: universality of the antifoaming agent, efficiency of the antifoaming agent at low concentrations while preserving the capacity for foamed systems for re-foaming or multiple foaming, defoaming and re-foaming cycles.

20 cl, 2 tbl, 1 ex