Off-Spec Crude Oil Upgrading

Abstract

Included are processes and systems for upgrading off-spec crude oil. The processes and systems use a separator to take a sharp cut of a blend of off-spec crude oil and natural gas liquids (NGL) or butanes, so as to recover a valuable crude oil product from the separator. The processes and systems can be performed and located on an oil production site.

What is claimed is: 
     
         1 . An off-spec crude oil upgrading process comprising:
 combining a first stream comprising an off-spec crude oil that does not meet a pipeline specification with a second stream comprising natural gas liquids (NGL) or butane to yield a blend of i) the off-spec crude oil and ii) the NGL or butane; and   separating the blend into i) an overhead stream comprising C 3 − hydrocarbons and light compounds and ii) a bottom stream comprising a crude oil product comprising the NGL or butane.   
     
     
         2 . The process of  claim 1 , wherein combining the first stream and the second stream and separating the blend are performed at an oil-production site. 
     
     
         3 . The process of  claim 2 , wherein combining the first stream and the second stream and separating the blend are performed upstream of a pipeline. 
     
     
         4 . The process of  claim 1 , further comprising sending the crude oil product to a pipeline. 
     
     
         5 . The process of  claim 1 , wherein the blend is formed outside of and upstream of a separator. 
     
     
         6 . The process of  claim 1 , wherein the blend is formed inside a separator. 
     
     
         7 . The process of  claim 6 , further comprising:
 feeding the first stream and the second stream separately to the separator; and   recovering the overhead stream and the bottom stream from the separator.   
     
     
         8 . The process of  claim 1 , wherein the off-spec crude oil has a Reid Vapor Pressure (RVP) greater than about 10 pounds per square inch (psi). 
     
     
         9 . The process of  claim 1 , wherein the crude oil product has a Reid Vapor Pressure (RVP) of about 8 pounds per square inch absolute (psia) to about 25 psia. 
     
     
         10 . The process of  claim 1 , wherein separating the blend is performed in a distillation column. 
     
     
         11 . The process of  claim 10 , wherein the distillation column is configured to take a sharp cut such that C 3 − hydrocarbons and light compounds flow in the overhead stream and compounds of C 4  hydrocarbons and heavier are recovered in the bottom stream, wherein the sharp cut is i) less than about 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 weight percent (wt %) butane contained in reject vapors based on a total weight of the reject vapors, ii) less than about 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.1, or 0.01 wt % propane contained in the crude oil product based on a total weight of the crude oil product, iii) less than about 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 wt % butane contained in the reject vapors based on a total weight of the blend, iv) less than about 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 wt % propane contained in the crude oil product based on a total weight of the blend, or v) combinations thereof. 
     
     
         12 . The process of  claim 1 , wherein less than about 0.1 weight percent (wt %) butane is contained in reject vapors recovered from the overhead stream based on a total weight of the reject vapors, wherein less than about 10 wt % propane is contained in the crude oil product based on a total weight of the crude oil product, wherein less than about 0.1 wt % butane is contained in the reject vapors based on a total weight of the blend, wherein less than about 10 wt % propane is contained in the crude oil product based on a total weight of the blend. 
     
     
         13 . An off-spec crude oil upgrading process comprising:
 combining an off-spec crude oil with natural gas liquids (NGL) or butane to yield a blend comprising i) the off-spec crude oil and ii) the NGL or butane, wherein the off-spec crude oil has a Reid Vapor Pressure (RVP) of greater than about 10 pounds per square inch (psi); and   controlling an amount of C 4  hydrocarbons recovered from an overhead stream of a separator such that a crude oil product produced by the separator has a RVP of about 8 pounds per square inch absolute (psia) to about 25 psia.   
     
     
         14 . The process of  claim 13 , wherein the blend is formed outside of and upstream of the separator, and wherein the process further comprises feeding the blend to the separator. 
     
     
         15 . The process of  claim 13 , wherein the blend is formed inside the separator, and wherein the process further comprises:
 feeding the off-spec crude oil to the separator separately from feeding the NGL or butane to the separator;   recovering the overhead stream and a bottom stream comprising the crude oil product from the separator.   
     
     
         16 . The process of  claim 13 , wherein combining a first stream and a second stream and separating the blend are performed at an oil-production site. 
     
     
         17 . The process of  claim 16 , wherein combining the first stream and the second stream and separating the blend are performed upstream of a pipeline. 
     
     
         18 . An off-spec crude oil upgrading system comprising:
 a blend comprising i) an off-spec crude oil and ii) natural gas liquids (NGL) or butane; and   a separator configured to separate the blend into i) an overhead stream comprising C 3 − hydrocarbons and light compounds and ii) a bottom stream comprising a crude oil product comprising the NGL or butane.   
     
     
         19 . The system of  claim 18 , wherein the separator is located at an oil-production site where the off-spec crude oil is produced. 
     
     
         20 . The system of  claim 18 , wherein the blend is formed outside of and upstream of the separator. 
     
     
         21 . The system of  claim 18 , wherein the blend is formed inside the separator.