Chemically enhanced thermal recovery of heavy oil

Abstract

Described herein are methods for removing heavy oils from underground reservoirs. The methods involve the use of chemical compositions in combination with steam techniques for the efficient removal of heavy oils.

1 - 18 . (canceled) 
   
   
       19 . A process for removing heavy oil from an underground heavy oil reservoir, comprising:
 injecting into the reservoir (i) steam, (ii) a mixture comprising an ionic surfactant and a nonionic surfactant, wherein the anionic surfactant is selected from the group consisting of a sulfosuccinate, an alkyl naphthalene sulfonate, an olefinic sulfonate, a fatty acid sulfonate, a sulfo carboxylate, a phosphono carboxylate, a thiosulfate, or any combination thereof, and (iii) an alcohol; and   removing the oil from the reservoir.   
   
   
       20 - 25 . (canceled) 
   
   
       26 . A process for removing heavy oil from an underground heavy oil reservoir, comprising:
 injecting into the reservoir (i) steam, (ii) a mixture comprising an ionic surfactant and a nonionic surfactant, wherein the nonionic surfactant is selected from the group consisting of an amine oxide; a phosphine oxide; a sugar alkylate; an acetylenic surfactant; an alkyl polyglucoside, or any combination thereof, and (iii) an alcohol; and   removing the oil from the reservoir.