Patent ID: 9255220
Filing Date: 2016-02-09
CPC Classification: B01D,C09K

Claim Text:
1. A method comprising: adding an effective amount of a defoamer composition to a foamed fluid, where the amount is sufficient to result in a clean break of the foamed fluid, where the defoamer composition includes, on a volume basis: between about 40 vol. % and about 80 vol. % distilled water and/or other waters, between about 10 vol. % and about 30 vol. % of a silicone anti-foam agent including 60.0 wt. % of water, 7.0-13.0 wt. % of a first polydimethylsiloxane, and optionally 5.0 wt. % of methylcellulose, and between about 10 vol. % and about 30 vol. % of an active silicone anti-foam agent including 70.0 wt. %-90.0 wt. % water, 7.0 wt. %-13.0 wt. % of a second polydimethylsiloxane, 1.0 wt. %-5.0 wt. % hydroxyethyl cellulose, 1.0 wt. %-5.0 wt. % of treated amorphous silica, and <1.0 wt. % of C where the composition is stable at temperatures up to about 450° F. and is effective at concentration of less than or equal to 500 ppm in all recyclable foamed fluids including recyclable foamed drilling fluids, recyclable foamed completion fluids, recyclable foamed fracturing fluids, recyclable foamed stimulating fluids, and foaming cements used in downhole applications.