Abstract Hydrocarbon products from viscous tar sands are recovered by continuously injecting a hot solvent containing relatively large amounts of aromatics into the formation. Alternatively, steam and solvent are cyclically and continuously injected into the formation to recover the values. The last stimulation is by steam so that solvent is recovered. A third alternative is to continuously inject a mixture of steam and solvent vapors and liquid into the formation. In all cases, the solvent, except perhaps for startup, is produced at the site, as in a conventional topping unit, which alternatively is combined with a conventional visbreaking or reforming unit to increase the volume and/or aromaticity of the solvent produced.
IN A PROCESS FOR RECOVERING HYDROCARBONS FROM A SUBTERRANEAN DEPOSIT OF HYDROCARBONS HAVING HIGH VISCOSITIES AND INCLUDING TAR SANDS, OIL AND TAR DEPOSITS BY STIMULATION THROUGH THE INJECTION OF A SOLVENT INTO THE DEPOSIT, THE IMPROVEMENT WHICH COMPRISES: A. PRODUCING A SOLVENT FROM THE RECOVERED HYDROCARBONS CLOSE TO THE RECOVERY AREA, B. HEATING THE PRODUCED SOLVENT TO AN ELEVATED INJECTION TEMPERATURE OF FROM ABOUT 200* TO ABOUT 650*F, C. INJECTING THE HEATED SOLVENT INTO THE DEPOSIT TO DEMULSIFY HYDROCARBON-WATER EMULSIONS AND CUT RELATIVELY HEAVY HYDROCARBONS, AND D. RECOVERING AT LEAST A PORTION OF THE STIMULATED HYDROCAR-
Claim 2
Dependent Claim
96 words
IN A PROCESS FOR RECOVERING HYDROCARBONS FROM A SUBTERRANEAN DEPOSIT OF HYDROCARBONS HAVING HIGH VISCOSITIES AND INCLUDING TAR SANDS, OIL AND TAR DEPOSITS BY STIMULATION THROUGH THE INJECTION OF A SOLVENT INTO THE DEPOSIT, THE IMPROVEMENT WHICH COMPRISES: A. PRODUCING A SOLVENT FROM THE RECOVERED HYDROCARBONS CLOSE TO THE RECOVERY AREA, B. HEATING THE PRODUCED SOLVENT TO AN ELEVATED INJECTION TEMPERATURE OF FROM ABOUT 200* TO ABOUT 650*F, C. INJECTING THE HEATED SOLVENT INTO THE DEPOSIT TO DEMULSIFY HYDROCARBON-WATER EMULSIONS AND CUT RELATIVELY HEAVY HYDROCARBONS, AND D. RECOVERING AT LEAST A PORTION OF THE STIMULATED HYDROCAR-
Claim 3
Dependent Claim
20 words
The improvement claimed in claim 1 wherein the solvent has a high aromatic content for the solubilization of deposit asphaltenes.
Claim 4
Dependent Claim
20 words
The improvement claimed in claim 2 wherein the solvent is depentanized naptha having a maximum end point of about 800*F.
Claim 5
Dependent Claim
21 words
The improvement claimed in claim 3 wherein the solvent has a boiling point range of from about 200* to about 500*F.