Multi-stage hydroprocessing

Abstract

A process for hydroprocessing liquid petroleum and chemical streams in two or more hydroprocessing stages wherein the liquid and vapor products from the first stage are sent to a separation zone wherein a liquid phase fraction is separated from a vapor phse fraction which contains vaporized heary hydrocarbon components. The vapor phase fraction is passed to a sorption zone wherein at least a portion of the heavy hydrocarbon components is removed. Both the liquid phase fraction and the sorbed heavy hydrocarbon components are sent to at least one additional hydroprocessing stage.

What is claimed is:  
     
         1 . A two stage process for hydroprocessing a hydrocarbonaceous feedstock which process comprises: 
 (a) reacting said feedstock in a first reaction stage in the presence of a hydrogen-containing treat gas, said reaction stage containing one or more reaction zones operated at hydroprocessing conditions wherein each reaction zone contains a bed of hydroprocessing catalyst;    (b) passing the resulting product stream to a separation zone wherein a vapor phase fraction and a liquid phase fraction are produced, which vapor phase fraction containing vaporized high boiling hydrcarbon components;    (c) conducting at least a portion of said vapor phase fraction to a sorption zone wherein it is contacted with a sorption agent that is at a temperature less than that of said vapor phase fraction, thereby sorbing at least a portion of the vaporized high boiling hydrocarbon components from the vapor phase fraction;    (d) conducting said liquid phase fraction to a second reaction stage in the presence of a hydrogen-containing treat gas, said reaction stage containing one or more reaction zones operated at hydroprocessing conditions wherein each reaction zone contains a bed of hydroprocessing catalyst; and    e) collecting the hydroprocessed product stream for said second reaction stage.    
     
     
         2 . The process of  claim 1  wherein step (c) above comprises one or more of: (i) partial condensation of the vapor phase fraction, (ii) usage of a contacting device with partial condensation and reflux to achieve multiple vapor liquid equilibrium stages, (iii) contacting the vapor phase stream with a heavy liquid stream, and (iv) use of a dephlegmator.  
     
     
         3 . The process of  claim 1  wherein the contacting with the vapor phase fraction is performed in a trayed or packed device to result in multiple vapor liquid equilibrium stages.  
     
     
         4 . The process of  claim 3  wherein the sorption agent is selected from the group consisting of vaccum resid, atmospheric resid, vacuum gas oil, atmospheric gas oil, heavy atmospheric gas oil, steam cracked gas oil, deasphalted oil, light cat cycle oil, and the hydroprocessed product from first stage hydroprocessing.  
     
     
         5 . The process of  claim 4  wherein the sorption agent is the hydroprocessed product from first stage hydroprocessing.  
     
     
         6 . The process of  claim 3  wherein heavy hydrocarbon components sorbed from the vapor phase fraction are passed to the second reaction stage.  
     
     
         7 . The process of  claim 1  wherein the hydrocarbonaceous feedstream is a heavy feedstock selected from the group consisting of vacuum resid, atmospheric resid, vacuum gas oil, atmospheric gas oil, heavy atmospheric gas oil, steam cracked gas oil, desaphalted oil, and light cat cycle oil.  
     
     
         8 . The process of  claim 1  wherein the feedstock is a Fischer-Tropsch reactor product stream.