Integrated Vacuum Distillate Recovery Process

Abstract

A system for recovering diesel products from a feed stream comprises an atmospheric crude unit, a vacuum crude unit, and a vacuum distillate recovery unit. The atmospheric crude unit comprises a crude feed inlet line, a diesel product outlet line, an atmospheric gas oil product outlet line, and a residual product outlet line. The vacuum crude unit comprises a residual product inlet line in fluid communication with the residual product outlet line from the atmospheric crude unit, a light vacuum gas oil product outlet line, and an overhead vapor outlet line. The vacuum distillate recovery unit comprises a gas oil inlet line, an overhead product line, and a second diesel product outlet line. The gas oil inlet line is in fluid communication with the atmospheric gas oil product outlet line from the atmospheric crude unit and the light vacuum gas oil product outlet line from the vacuum crude unit.

What is claimed is: 
     
         1 . A system for recovering diesel products from a feed stream, the system comprising:
 an atmospheric crude unit, wherein the atmospheric crude unit comprises a crude feed inlet line, a diesel product outlet line, an atmospheric gas oil product outlet line, and a residual product outlet line;   a vacuum crude unit, wherein the vacuum crude unit comprises a residual product inlet line, a light vacuum gas oil product outlet line, and an overhead vapor outlet line, wherein the residual product inlet line is in fluid communication with the residual product outlet line; and   a vacuum distillate recovery unit, wherein the vacuum distillate recovery unit comprises a gas oil inlet line, an overhead product line, and a second diesel product outlet line, wherein the gas oil inlet line is in fluid communication with the atmospheric gas oil product outlet line from the atmospheric crude unit and the light vacuum gas oil product outlet line from the vacuum crude unit.   
     
     
         2 . The system of  claim 1 , further comprising: a vacuum system, wherein the vacuum system is in fluid communication with the overhead vapor outlet line from the vacuum crude unit and the overhead product line from the vacuum distillate recovery unit. 
     
     
         3 . The system of  claim 1 , further comprising: a vacuum system, wherein the vacuum system is in fluid communication with the overhead vapor outlet line from the vacuum crude unit, and wherein the overhead product line from the vacuum distillate recovery unit is in fluid communication with the vacuum crude unit. 
     
     
         4 . The system of  claim 1 , further comprising: a first vacuum system in fluid communication with the overhead vapor outlet line from the vacuum crude unit, and a second vacuum system in fluid communication with the overhead product line from the vacuum distillate recovery unit. 
     
     
         5 . The system of  claim 1 , wherein the vacuum distillate recovery unit comprises a distillation column comprising the gas oil inlet line, the overhead product line, and the second diesel product outlet line, wherein the distillation column comprises a side draw line in fluid communication with the second diesel product outlet line and a cooling circuit, wherein the cooling circuit comprises a heat exchanger configured to cool at least a portion of a fluid stream drawn from the distillation column through the side draw line and return the cooled portion of the fluid stream to the distillation column. 
     
     
         6 . The system of  claim 1 , wherein the vacuum distillate recovery unit comprises a distillation column comprising the gas oil inlet line, the overhead product line, and the second diesel product outlet line, wherein the distillation column further comprises a reboiler configured to vaporize a portion of a liquid in the lower portion of the distillation column and return a vapor to the distillation column. 
     
     
         7 . The system of  claim 6 , wherein the distillation column further comprises a light gas oil outlet line. 
     
     
         8 . The system of  claim 7 , wherein the light gas oil outlet line is located above the gas oil inlet line and below the second diesel product outlet line. 
     
     
         9 . A method of recovering diesel from a crude oil feed stream, the method comprising:
 separating a crude oil feed stream into a plurality of streams in an atmospheric crude unit, wherein the plurality of streams comprise a first diesel product stream, an atmospheric gas oil stream, and a residual product stream;   receiving the atmospheric gas oil stream and a light vacuum gas oil stream at a distillation column; and   separating the atmospheric gas oil stream and the light vacuum gas oil stream into a plurality of product streams in the distillation column, wherein the plurality of product streams comprise an overhead vapor stream, a second diesel product stream, and a medium gas oil stream.   
     
     
         10 . The method of  claim 9 , further comprising: separating the residual product stream in a vacuum crude unit into a plurality of product streams, wherein the plurality of product streams comprise the light vacuum gas oil stream. 
     
     
         11 . The method of  claim 10 , wherein the vacuum crude unit is in fluid communication with a vacuum system while separating the residual product stream. 
     
     
         12 . The method of  claim 11 , wherein the distillation column is in fluid communication with the vacuum system while separating the atmospheric gas oil stream and the light vacuum gas oil stream. 
     
     
         13 . The method of  claim 11 , wherein the distillation column is in fluid communication with a second vacuum system while separating the atmospheric gas oil stream and the light vacuum gas oil stream, wherein the vacuum system and the second vacuum system are separate vacuum systems. 
     
     
         14 . The method of  claim 9 , further comprising combining the atmospheric gas oil stream and the light vacuum gas oil stream before separating the atmospheric gas oil stream and the light vacuum gas oil stream into the plurality of product streams. 
     
     
         15 . The method of  claim 9 , wherein separating the atmospheric gas oil stream and the light vacuum gas oil stream comprises:
 introducing the atmospheric gas oil stream and the light vacuum gas oil stream into the distillation column;   removing a fluid stream from the distillation column during the separation;   passing a first portion of the fluid stream back to the distillation column;   passing a second portion of the fluid stream to a heat exchanger;   cooling the second portion of the fluid stream in the heat exchanger to create a cooled fluid;   passing the cooled fluid back to the distillation column; and   removing a third portion of the fluid stream as the second diesel product stream.   
     
     
         16 . The method of  claim 15 , wherein separating the atmospheric gas oil stream and the light vacuum gas oil stream further comprises:
 removing a second fluid stream from the distillation column during the separation, wherein the second fluid stream is removed from below the fluid stream and above a location at which the atmospheric gas oil stream and the light vacuum gas oil stream are introduced into the distillation column, wherein the second fluid stream comprises a light gas oil product stream.   
     
     
         17 . The method of  claim 16 , wherein separating the atmospheric gas oil stream and the light vacuum gas oil stream further comprises: reboiling a portion of a liquid stream in a lower portion of the distillation column during the separating. 
     
     
         18 . A method of recovering diesel, the method comprising;
 separating a crude oil feed stream into a plurality of product streams in an atmospheric crude unit, wherein the plurality of product streams comprises a first diesel product stream, an atmospheric gas oil stream, and a residual product stream;   separating the residual product stream into a plurality of second product streams in a vacuum crude unit, wherein the plurality of second product streams comprises a light vacuum gas oil and an overhead stream;   receiving the atmospheric gas oil stream and the light vacuum gas oil stream at a distillation column; and   separating the atmospheric gas oil stream and the light vacuum gas oil stream into a plurality of third product streams in the distillation column, wherein the plurality of third product streams comprises a second diesel product stream.   
     
     
         19 . The method of  claim 18 , wherein the plurality of third product streams comprises a second overhead stream, and wherein the overhead stream from the vacuum crude unit and the second overhead stream from the distillation column are in fluid communication with a vacuum system. 
     
     
         20 . The method of  claim 18 , wherein the plurality of third product streams comprises a second overhead stream, and wherein the second overhead stream is in fluid communication with the vacuum crude unit, and wherein the overhead stream from the vacuum crude unit is in fluid communication with a vacuum system.