Upgrading heavy hydrocarbon oils

Abstract

A process using supercritical water-oil emulsion to upgrade a heavy hydrocarbon feedstock into an upgraded hydrocarbon product or syncrude with highly desirable properties (low sulfur content, low metals content, lower density (higher API), lower viscosity, lower residuum content, etc.) is disclosed. The process does not require external supply of hydrogen nor does it use externally supplied catalysts.

1 . A process for upgrading hydrocarbons comprising:
 (a) mixing hydrocarbons with a fluid comprising water in a mixing zone to form an emulsion;   (b) heating the emulsion to a temperature higher than the critical temperature of water;   (c) reacting the emulsion in a reaction zone under supercritical water conditions in the absence of externally added hydrogen and externally supplied catalyst for a residence time sufficient to allow upgrading reactions to occur;   (d) withdrawing a single-phase reaction product from the reaction zone; and   (e) separating the reaction product into gas, effluent water, and upgraded hydrocarbon phases.   
   
   
       2 . A process according to  claim 1 , wherein the hydrocarbons are heavy hydrocarbons selected from the group consisting of whole heavy petroleum crude oil, tar sand bitumen, heavy hydrocarbon fractions obtained from crude petroleum oils, heavy vacuum gas oils, vacuum residuum, petroleum tar, coal tar and their mixtures. 
   
   
       3 . A process according to  claim 1 , wherein the emulsion has oil to water ratio of from 10:1 to 1:5. 
   
   
       4 . A process according to  claim 1 , wherein the conditions in the mixing zone include a temperature higher than the critical temperature of water and a pressure greater than the critical pressure of water. 
   
   
       5 . A process according to  claim 1 , wherein the supercritical water conditions include a temperature from 374° C. to 1000° C., a pressure from 3,205 psia to 10,000 psia an oil/water volume ratio from 1:0.1 to 1:10 and where the residence time is from 1 minute to 6 hours. 
   
   
       6 . A process according to  claim 1 , wherein the supercritical water conditions include a temperature from 374° C. to 600° C., a pressure from 3,205 psia to 7,200 psia, an oil/water volume ratio from 1:0.5 to 1:3 and where the residence time is from 8 minutes to 2 hours. 
   
   
       7 . A process according to  claim 1 , wherein the supercritical water conditions include a temperature from 374° C. to 400° C., a pressure from 3,205 psia to 4,000 psia, an oil/water volume ratio from 1:1 to 1:2 and where the residence time is from 10 to 40 minutes. 
   
   
       8 . A process according to  claim 1 , wherein the mixture in the reaction zone is reacted in the absence of any catalyst or promoter. 
   
   
       9 . A process according to  claim 1 , wherein the water is drinking water, treated wastewater, untreated wastewater, river water, lake water, seawater, produced water or their mixtures. 
   
   
       10 . A process according to  claim 1 , wherein a surfactant or emulsifier is added to the mixing zone in step (a) 
   
   
       11 . A process according to  claim 1 , wherein an oil-water emulsion is formed using a micro-channel mixer in step (a) 
   
   
       12 . A process according to  claim 1 , wherein an oil-water emulsion is water-in-oil 
   
   
       13 . A process according to  claim 1 , wherein an oil-water emulsion is oil-in-water