Removel Of Hydrocarbons From Particulate Solids

Abstract

A process and composition for removing heavy oil and bitumen from oil sands is disclosed. The composition comprises an emulsion of d-limonene and water, with an anionic surfactant as an emulsifying agent. The emulsion is contacted with an oil sand slurry until the aqueous and hydrocarbon phases separate. The process may take place at temperatures less than about 80° C.

What is claimed is: 
     
         1 . A process for removing heavy oil or bitumen from oil sands and reducing the density of the heavy oil or bitumen, comprising the steps of contacting the oil sands with an aqueous emulsion of a monocyclic terpene to form a mixture, agitating the mixture, allowing the aqueous and hydrocarbon phases to separate, and recovering the hydrocarbon phase having an API density of at least about 22 degrees. 
     
     
         2 . The process of  claim 1  wherein the monocyclic terpene comprises d-limonene. 
     
     
         3 . The process of  claim 1  or  2  wherein the emulsion further comprises an emulsifying agent. 
     
     
         4 . The process of  claim 3  wherein the emulsifying agent comprises an anionic surfactant. 
     
     
         5 . The process of  claim 4  wherein the anionic surfactant comprises an alkyl aryl sulfonate. 
     
     
         6 . The process of  claim 5  wherein the emulsion further comprises a defoaming agent. 
     
     
         7 . The process of  claim 3  wherein the emulsion is a oil-in-water emulsion. 
     
     
         8 . The process of  claim 2  wherein the emulsion comprises about 40% d-limonene by volume and the mixture comprises at least about 4% emulsion by volume. 
     
     
         9 . The process of  claim 8  wherein the process is operated at a temperature of greater than 20° C. and less than about 80° C. 
     
     
         10 . The process of  claim 9  wherein the process is operated at a temperature greater than about 40° C. and less than about 60° C. 
     
     
         11 . A composition for cleaning heavy oil or bitumen from solid particles, comprising an emulsion of d-limonene and water, stabilized by an emulsifying agent comprising an anionic surfactant. 
     
     
         12 . The composition of  claim 11  wherein the anionic surfactant is an alkyl aryl sulfonate. 
     
     
         13 . The composition of  claim 12  comprising about 40% d-limonene, less than about 1% alkyl aryl sulfonate, and about 60% water or an aqueous solution. 
     
     
         14 . The composition of  claim 13  wherein the aqueous solution comprises a solution of sodium bicarbonate. 
     
     
         15 . A plant for processing feedstock comprising oil sand or contaminated soil to separate hydrocarbons from solid particles, comprising:
 (a) a feed hopper for feeding feedstock into a mixing vessel;   (b) an inlet for adding a composition according to  claim 11 ,  12 ,  13  or  14  to the mixing vessel to form a slurry;   (c) means for agitating the slurry until the emulsion breaks;   (d) an oil skimmer for recovering hydrocarbons;   (e) means for recovering the solids, substantially free of hydrocarbons.   
     
     
         16 . The plant of  claim 15  further comprising at least one recovery tower for receiving the slurry from the mixing vessel and which comprises the oil skimmer. 
     
     
         17 . The plant of  claim 16  further comprising means for recovering the aqueous phase and recycling the aqueous phase into the mixing vessel. 
     
     
         18 . A hydrocarbon product comprising a monocyclic terpene and a heavy oil or bitumen, said product resulting from the process of any one of  claims 1  to  10 . 
     
     
         19 . The hydrocarbon product of  claim 18  wherein the product has an API density of at least about 22 degrees.