Patent EA-004505-B1 (EA)
Title: Method of generating gas bubbles in oleaginous liquids, oil base well drilling and servicing fluid and method of drilling a well
Inventor: MORGAN JULIE B M A
IPC: B01F23/00
Filed: 2001-04-04
Abstract: 1. A method of generating gas bubbles in oleaginous liquids which comprises adding a silicone oil to the oleaginous liquid and thereafter subjecting the oleaginous liquid to mechanical forces in the presence of a gas. 2. The method of claim 1 wherein the oleaginous liquid is selected from the group consisting of petroleum oils or fractions thereof, alpha olefins, internal olefins, oligomers of unsaturated hydrocarbons, carboxylic acid esters, phosphoric acid esters, ethers, polyalkylene glycols, diglymes, acetals, and mixtures thereof. 3. The method of claim 1 or 2 wherein the gas is selected from the group consisting of air, nitrogen, carbon dioxide, and mixtures thereof. 4. The method of any one of claims 1-3 wherein the mechanical forces are selected from the group consisting of mixing the silicone oil-containing oleaginous liquid wherein a vortex is created, pumping the silicone oil-containing oleaginous liquid wherein the liquid is subjected to a pressure of at least 3447.5 kPa, or in a combination of mixing and pumping thereof. 5. The method of any one of claims 1-4 wherein the silicone oil is a polydimethylsiloxane oil having a nominal viscosity at 25 degree C of about 0.5 mm<2>c to about 2500000 mm<2>c. 6. The method of any one of claims 1-4 wherein the silicone oil is selected from the group consisting of a polydimethylsiloxane, polydialkylsiloxane, polydiphenylsiloxane, poly(dimethyl/diphenylsiloxane copolymer and polymethylalkylsiloxane. 7. An oil base well drilling and servicing fluid comprising an oleaginous liquid, a silicone oil and microbubbles. 8. The fluid of claim 7 wherein the silicone oil is selected from the group consisting of a polydimethylsiloxane, polydialkylsiloxane, polydiphenylsiloxane, poly(dimethyl/diphenylsiloxane copolymer and polymethylalkylsiloxane. 9. The fluid of claim 7 wherein the silicone oil is a polydimethylsiloxane oil having a nominal viscosity at 25 degree C of about 0.5 mm<2>c to about 2500000 mm<2>c. 10. The fluid of any one of claims 7-9 wherein the oleaginous liquid is selected from the group consisting of petroleum oils or fractions thereof, alpha olefins, internal olefins, oligomers of unsaturated hydrocarbons, carboxylic acid esters, phosphoric acid esters, ethers, polyalkylene glycols, diglymes, acetals, and mixtures thereof. 11. The fluid of any one of claims 7-9 wherein the microbubbles are generated by subjecting the silicone oil-containing oleaginous liquid to mechanical forces. 12. The fluid of claim 11 wherein the mechanical forces are selected from the group consisting of mixing the silicone oil-containing oleaginous liquid wherein a vortex is created, pumping the silicone oil-containing oleaginous liquid wherein the liquid is subjected to a pressure of at least 3447.5 kPa, or in a combination of mixing and pumping thereof. 13. The fluid of any one of claims 7-12 wherein comprising a viscosifier such that the fluid has a low shear rate viscosity as measured with a Brookfield Viscometer at 0.5 rpm of at least about 20 Paxc. 14. The fluid of claim 11 wherein the viscosifier is selected from the group consisting of as organophilic clays, colloidal fumed silicas, resins, polymers, dimer acids, fatty amine salts of anionic polysaccharides, fatty acid salts of cationic polysaccharides, oil-dispersible/soluble latex-type products, and mixtures thereof. 15. The fluid of claim 13 or 14 wherein having a low shear rate viscosity as measured with a Brookfield Viscometer at 0.5 rpm of at least about 40 Paxc. 16. The fluid of any one of claims 7-15 wherein the fluid contains from about 5% to about 25% by volume of the microbubbles. 17. The fluid of any one of claims 7-15 wherein the fluid contains at least 25% by volume of the microbubbles. 18. The fluid of any one of claims 7-17 wherein the fluid recirculating. 19. The fluid of any one of claims 7-18 wherein the microbubbles prevent loss of excess fluid into the formation. 20. The fluid of any one of claims 7-18 wherein the microbubbles effectively seal the formation. 21. A method of drilling or servicing a well in a subsurface formation comprising circulating the fluid in the well for drilling or servicing the wherein the fluid of any one of claims 7-20 is used as the fluid for drilling or servicing.