Process for the conversion of hydrocarbonaceous feedstock

Abstract

A hydrocarbonaceous feedstock is converted in a process comprising the following steps: (a) the feedstock is contacted with hydrogen under hydrotreating conditions to yield hydrotreated product; (b) the hydrotreated product is subjected to a separation treatment to separate at least hydrogen from the hydrotreated product to obtain a liquid hydrotreated product stream; (c) at least a portion of the liquid hydrotreated product stream is subjected to a stripping treatment to separate a light product from the liquid hydrotreated product stream, leaving a heavy hydrotreated product; (d) the heavy hydrotreated product is separated under reduced pressure into a least one gaseous stripped fraction and at least one liquid stripped fraction in a separation zone, wherein at least a portion of a liquid stripped fraction is reheated and recycled to the separation zone, in which process at least a portion of the liquid stripped fraction is reheated by heat exchange between at least a portion of the liquid hydrotreated product stream and/or at least a portion of the heavy hydrotreated product.

1 . A process for the conversion of a hydrocarbonaceous feedstock comprising the following steps:
 (a) the feedstock is contacted with hydrogen under hydrotreating conditions to yield hydrotreated product;   (b) the hydrotreated product is subjected to a separation treatment to separate at least hydrogen from the hydrotreated product to obtain a liquid hydrotreated product stream;   (c) at least a portion of the liquid hydrotreated product stream is subjected to a stripping treatment to separate a light product from the liquid hydrotreated product stream, leaving a heavy hydrotreated product;   (d) the heavy hydrotreated product is separated under reduced pressure into a least one gaseous stripped fraction and at least one liquid stripped fraction in a separation zone, wherein at least a portion of a liquid stripped fraction is reheated and recycled to the separation zone,   in which process at least a portion of the liquid stripped fraction is reheated by heat exchange between at least a portion of the liquid hydrotreated product stream and/or at least a portion of the heavy hydrotreated product.   
     
     
         2 . A process according to  claim 1 , in which the hydrocarbonaceous feedstock comprises sulphur compounds and the hydrotreating conditions comprise hydrodesulphurisation conditions. 
     
     
         3 . A process according to  claim 1 , in which the hydrotreating conditions comprise a temperature ranging from 250 to 480° C., a pressure from 10 to 150 bar, and a weight hourly space velocity of from 0.1 to 10 hr −1 . 
     
     
         4 . A process according to  claim 1 , in which the catalyst comprises a carrier and at least one Group VIB and a Group VIII metal. 
     
     
         5 . A process according to  claim 1 , in which the stripping is carried out with steam. 
     
     
         6 . A process according to  claim 1 , in which the stripping is conducted at a temperature ranging from 100 to 350° C. and a pressure ranging from 1 to 50 bar. 
     
     
         7 . A process according to  claim 1 , in which the separation zone in step (d) comprises a stripping section. 
     
     
         8 . A process according to  claim 7 , in which the separation zone of step (d) comprises a rectifying section, in addition to a stripping section. 
     
     
         9 . A process according to  claim 1 , in which the heat exchange with said at least portion of the liquid stripped fraction is conducted with said at least portion of the liquid hydrotreated product stream. 
     
     
         10 . A process according to  claim 1 , in which the heat exchange with said at least portion of the liquid stripped fraction is conducted with said at least portion of the heavy hydrotreated product. 
     
     
         11 . A process according to  claim 1 , in which at least 90% wt of the liquid stripped fraction is reheated by heat exchange. 
     
     
         12 . A process according to  claim 1 , in which part of the liquid stripped fraction is recovered as middle distillate product. 
     
     
         13 . A process according to  claim 1 , in which the gaseous stripped fraction is separated into at least a naphtha fraction and a water fraction. 
     
     
         14 . A process according to  claim 1 , in which the separation zone is a fractionation column wherein the conditions are a temperature of 80 to 300° C. and a pressure ranging from 0.005 to 1 bar. 
     
     
         15 . A process according to  claim 1 , in which said at least portion of the liquid stripped fraction is reheated to a temperature of from 125 to 350° C.