Supercritical hydrocarbon conversion process

Abstract

Supercritical conversion of hydrocarbons boiling above 538° C. (1000° F.) with a solvating hydrocarbon at a weight ratio of solvating hydrocarbon to high-boiling hydrocarbons of at least 2:1 and at conditions above the critical temperature and pressure of the high-boiling hydrocarbons-solvent mixture, in the presence of hot fluidized solids. The hydrocarbons are supplied to a reaction zone at a temperature below that of the hot solids supplied thereto, whereby the resulting hydrocarbons-solids suspension has a thermal equilibrium temperature corresponding to the reaction temperature. The conversion has high rates of sulfur, nitrogen and metals removal, nearly complete conversion to lower molecular weight products, high naphtha and distillate selectivity, and low coke formation. The supercritical conversion can replace crude distillation, vacuum distillation, solvent deasphalting, coking, hydrocracking, hydrotreating, and/or fluid catalytic cracking, and/or used in parallel with such unit operations for debottlenecking or increasing capacity.

1 . A method for converting heavy hydrocarbons to lower boiling hydrocarbons, comprising: 
 mixing a heavy hydrocarbon feed comprising one or more asphaltenes and having a normal boiling point above 538° C. (1000° F.) and one or more solvating hydrocarbons having a normal boiling point below 538° C. (1000° F.), at a weight ratio of the solvating hydrocarbons to the one or more asphaltenes of at least 2:1 to provide a feed mixture;    introducing the feed mixture into a reaction zone containing hot particulate solids to form a reaction mixture;    depositing coke onto the solids and producing a suspension comprising converted hydrocarbons having normal boiling points below 538° C. (1000° F.), the particulate solids, and the one or more solvating hydrocarbons; and    separating the particulate solids from the suspension to produce a solids-lean effluent stream.    
   
   
       2 . The method of  claim 1  further comprising partially condensing the solids-lean effluent stream to an effluent stream essentially free of solids and hydrocarbons boiling above 538° C. (1000° F.) and an effluent stream comprising a slurry mixture of liquid hydrocarbons and solids.  
   
   
       3 . The method of  claim 2 , further comprising separating the effluent stream essentially free of solids and hydrocarbons boiling above 538° C. (1000° F.) into solvent and one or more product streams comprising converted hydrocarbons having normal boiling points below 538° C. (1000° F.).  
   
   
       4 . The method of  claim 3  further comprising recycling at least a portion of the solvent as the solvating hydrocarbons in the feed mixture to the reaction zone.  
   
   
       5 . The method of  claim 4 , further comprising recycling at least a portion of the slurry mixture of liquid hydrocarbons and solids to the reaction zone.  
   
   
       6 . The method of  claim 4 , further comprising recycling at least a portion of the slurry mixture of liquid hydrocarbons and solids to a regeneration zone, regenerating the solids to remove coke and form hot regenerated particulate solids, and recirculating the regenerated particulate solids to the reaction zone.  
   
   
       7 . The method of  claim 6 , wherein the solids regeneration comprises combusting the coke in the presence of an oxygen-containing gas.  
   
   
       8 . The method of  claim 2 , wherein the condensed liquid hydrocarbons comprise less than 10 weight percent of the one or more asphaltenes provided in the feed mixture to the reaction zone.  
   
   
       9 . The method of  claim 6 , wherein the hot particulate solids recirculated to the reaction zone have a particle size distribution substantially between 25 and 350 microns.  
   
   
       10 . The method of  claim 6 , wherein the hot particulate solids are maintained in a transport hydrodynamic regime in the reaction and regeneration zones.  
   
   
       11 . The method of  claim 6 , wherein the hot particulate solids comprise refractory oxides.  
   
   
       12 . The method of  claim 11 , wherein the refractory oxides are selected from SiO2, Al2O3, AlPO4, TiO2, ZrO2, Cr2O3, and mixtures thereof.  
   
   
       13 . The method of  claim 2 , further comprising recovering the solvating hydrocarbons from the effluent stream essentially free of solids and hydrocarbons boiling above 538° C. (1000° F.) and recycling the solvating hydrocarbons to the reaction zone.  
   
   
       14 . The method of  claim 1 , wherein the weight ratio of solvating hydrocarbons to heavy hydrocarbons in the heavy hydrocarbon feed mixture is from 2:1 to 10:1.  
   
   
       15 . The method of  claim 1 , wherein the solvating hydrocarbons comprise light naphtha, heavy naphtha, distillates, gas oils, or combinations thereof.  
   
   
       16 . The method of  claim 1 , wherein the reaction mixture is maintained in a single phase.  
   
   
       17 . The method of  claim 1 , wherein the reaction mixture is maintained at a temperature and pressure outside a retrograde regime of its fluid phase.  
   
   
       18 . The method of  claim 1 , wherein the heavy hydrocarbon feed consists essentially of one or more asphaltenes.  
   
   
       19 . A method for converting heavy hydrocarbons to lower boiling hydrocarbons, comprising: 
 mixing a heavy hydrocarbon feed comprising one or more asphaltenes and having a normal boiling point above 538° C. (1000° F.) and one or more solvating hydrocarbons having a normal boiling point below 538° C. (1000° F.), at a weight ratio of the solvating hydrocarbons to the one or more asphaltenes of at least 2:1 to provide a feed mixture;    introducing the feed mixture into a reaction zone containing hot particulate solids to form a reaction mixture;    depositing coke onto the solids and producing a suspension comprising converted hydrocarbons having normal boiling points below 538° C. (1000° F.), the particulate solids, and the one or more solvating hydrocarbons;    separating the particulate solids from the suspension to produce a solids-lean effluent stream;    condensing the solids-lean effluent stream to an effluent stream essentially free of solids and hydrocarbons boiling above 538° C. (1000° F.) and an effluent stream comprising a slurry mixture of liquid hydrocarbons and solids; and    separating the effluent stream essentially free of solids and hydrocarbons boiling above 538° C. (1000° F.) into solvent and one or more product streams comprising converted hydrocarbons having normal boiling points below 538° C. (1000° F.);    
   
   
       20 . A method for converting heavy hydrocarbons to lower boiling hydrocarbons, comprising: 
 mixing a heavy hydrocarbon feed consisting essentially one or more asphaltenes having a normal boiling point above 538° C. (1000° F.) and one or more solvating hydrocarbons having a normal boiling point below 538° C. (1000° F.), at a weight ratio of the solvating hydrocarbons to the one or more asphaltenes of at least 2:1 to provide a feed mixture;    introducing the feed mixture into a reaction zone containing hot particulate solids to form a reaction mixture;    depositing coke onto the solids and producing a suspension comprising converted hydrocarbons having normal boiling points below 538° C. (1000° F.), the particulate solids, and the one or more solvating hydrocarbons;    separating the particulate solids from the suspension to produce a solids-lean effluent stream;    condensing the solids-lean effluent stream to an effluent stream essentially free of solids and hydrocarbons boiling above 538° C. (1000° F.) and an effluent stream comprising a slurry mixture of liquid hydrocarbons and solids; and    separating the effluent stream essentially free of solids and hydrocarbons boiling above 538° C. (1000° F.) into solvent and one or more product streams comprising converted hydrocarbons having normal boiling points below 538° C. (1000° F.).