Patent EA-004090-B1 (EA)
Title: Mineral acid enhanced thermal treatment for viscosity reduction of oils (ecb-0002)
Inventor: VARADARAJ RAMESH
IPC: C09K8/58
Filed: 2001-04-05
Abstract: 1. A method for decreasing the viscosity of crude oils and residuum comprising the steps of (a) contacting the crude oil or crude oil residuum with an effective amount of an acid consisting essentially of acid; (b) heating said crude oil or crude oil residuum and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said crude oil or residuum. 2. In a thermal visbreaking method for reducing the viscosity of crude oils and residuum by thermally treating the oils and residuum wherein the improvement comprises contacting the crude oil or residuum with an effective amount of an acid consisting essentially of acid and heating said crude oil or residuum and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said crude oil or residuum. 3. A crude oil or crude oil residuum having decreased viscosity prepared by (a) contacting the crude oil or residuum with an effective amount of an acid consisting essentially of acid, (b) heating said crude oil or residuum and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said crude oil or residuum. 4. The method of claim 1 wherein said acid is selected from the group consisting of mineral acids, organic acids, and mixtures thereof. 5. The method of claim 1 wherein said acid is a mineral acid. 6. The method of claim 4 wherein said acid is selected from the group consisting of sulfuric acid, hydrochloric acid, perchloric acid, acetic acid, para-toluene sulfonic acid, alkyl toluene sulfonic acids, mono di and trialkyl phosphoric acids, organic mono and di carboxylic acids, C3 to C16 organic carboxylic acids, succinic acid and mixtures thereof. 7. The method of claim 5 wherein said acid is sulfuric acid. 8. The method of claim 6 wherein said acid is acetic acid. 9. The method of claim 1 wherein said step (b) is conducted at temperatures of about 250 degree C to about 450 degree C. 10. The method of claim 1 wherein said step (b) is conducted at pressures of about 30 psi to about 300 psi. 11. The method of claim1 wherein said step (b) is conducted for times of about 0.15 hours to about 6 hours. 12. The method of claim 1 wherein said method step (b) further includes an inert gas purge. 13. The method of claim 1 wherein the amount of said acid utilized is about 10 ppm to about 1000 ppm based on the amount of crude oil or crude oil residuum. 14. The method of claim 1 wherein said method is conducted in an inert environment. 15. A method for preparing a water-in-oil emulsion comprising the steps of: (a) contacting said oil with acid; (b) heating said oil and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said oil; and (c) adding water and mixing until said water-in-oil emulsion is formed. 16. The method of claim 15, wherein said acid comprises at least one of mineral acid, organic acid, mixtures of at least two mineral acids, mixtures of at least two organic acids or mixtures of at least one mineral acid and at least one organic acid. 17. The method of claim 15, wherein said acid is added to said oil at a treat rate of about 10 to 1000 part per million. 18. The method of claim 15, wherein said step of heating said oil is at a temperature of about 250 degree C to about 450 degree C. 19. The method of claim 15, wherein said step of heating said oil is at a pressure of about 30 psi to about 300 psi. 20. The method of claim 15, wherein said step of heating said oil is conducted for times of about 0.15 hours to about 6 hours. 21. The method of claim 15, wherein said method further comprises the addition of solid particles to said oil prior to said step of adding water and mixing to form said emulsion. 22. The method of claim 21, wherein said solid particles are added at a treat rate of about 0.05wt% to about 0.25wt% based upon the weight of said oil. 23. A method for recovering hydrocarbons from a subterranean formation, said method comprising the steps of: (a) preparing a water-in-oil emulsion by (1) contacting said oil with acid; (2) heating said oil and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said oil; and (3) adding water and mixing to form said water-in-oil emulsion; (b) injecting said emulsion into said subterranean formation; and (c) recovering hydrocarbons from said subterranean formation using said emulsion. 24. The method of claim 23, wherein said acid comprises at least one of mineral acid, organic acid, mixtures of at least two mineral acids, mixtures of at least two organic acids or mixtures of at least one mineral acid and at least one organic acid. 25. The method of claim 23, wherein said acid is added to said oil at a treat rate of about 10 to 1000 part per million. 26. The method of claim 23, wherein said step of heating said oil is at a temperature of about 250 degree C to about 450 degree C. 27. The method of claim 23, wherein said step of heating said oil is at a pressure of about 30 psi to about 300 psi. 28. The method of claim 23, wherein said step of heating said oil is conducted for times of about 0.15 hours to about 6 hours. 29. The method of claim 23, wherein said method further comprises the addition of solid particles to said oil prior to said step of adding water and mixing to form said emulsion. 30. The method of claim 29, wherein said solid particles are added at a treat rate of about 0.05wt% to about 0.25wt% based upon the weight of said oil. 31. The method of claim 23, wherein said water-in-oil emulsion is used as a drive fluid to displace hydrocarbons in said subterranean formation. 32. The method of claim 23, wherein said water-in-oil emulsion is used as a barrier fluid to divert the flow of hydrocarbons in said subterranean formation. 33. A water-in-oil emulsion made by the process of: (a) contacting said oil with acid: (b) heating said oil and said acid at a temperature and for a time and at a pressure sufficient to decrease the viscosity of said oil; and (c) adding water and mixing until said water-in-oil emulsion is formed. 34. The emulsion of claim 33, further comprising the addition of solid particles to said oil prior to said step of adding water and mixing to form said emulsion.