Process for producing middle distillates

Abstract

The present invention relates to a process for producing middle distillates from a feedstock comprising a residual hydrocarbonaceous feedstock and a hydrogen deficient feedstock. The residual hydrocarbonaceous feedstock is deasphalted to obtain a deasphalted product of which at least 50 wt % has a boiling point above 550° C. and an asphaltic product. The deasphalted product is combined with the hydrogen deficient feedstock to produce a mixed deasphalted product, which is hydrodemetallized. The hydrodemetallized product is hydrotreated and hydrocracked. The hydrocracked product is subjected to a separation treatment to produce at least a middle distillate fraction.

1 . A process for producing middle distillates from a feedstock comprising a residual hydrocarbonaceous feedstock and a hydrogen deficient feedstock, comprising the steps of:
 (a) deasphalting the residual hydrocarbonaceous feedstock to obtain a deasphalted product of which at least 50 wt % has a boiling point above 550° C. and an asphaltic product;   (b) combining the deasphalted product with the hydrogen deficient feedstock to produce a mixed deasphalted product, wherein the hydrogen deficient feedstock has a hydrogen (H) content of at least 6 wt % to at most 11.3 wt %;   (c) hydrodemetallizing at least part of the mixed deasphalted product from step (b) to produce a hydrodemetallized product;   (d) hydrotreating at least part of the hydrodemetallized product from step (c) to produce a hydrotreated product;   (e) hydrocracking at least part of the hydrotreated product from step (d) to produce a hydrocracked product; and   (f) subjecting at least part of the hydrocracked product from step (e) to a separation treatment to produce at least a middle distillate fraction.   
     
     
         2 . The process according to  claim 1 , wherein the amount of hydrogen deficient feedstock comprises up to about 50 wt % of the mixed deasphalted product. 
     
     
         3 . The process according to  claim 1 , wherein the mixed deasphalted product has a hydrogen content less than at least 0.1 wt % of the deasphalted product via the addition of the hydrogen deficient feedstock. 
     
     
         4 . The process according to  claim 1 , wherein at least a portion of the hydrogen deficient feedstock includes a portion of renewable origin. 
     
     
         5 . The process according to  claim 1 , wherein the hydrogen deficient feedstock comprises slurry oil from a fluid catalytic cracker (FCC) unit. 
     
     
         6 . A process according to  claim 4 , wherein the hydrogen deficient feedstock comprises tall oil pitch from the distillation of crude tall oil. 
     
     
         7 . A process according to  claim 1 , wherein the middle distillate fraction in produced step (f) contain less than 10 ppmwt of sulphur. 
     
     
         8 . A process according to  claim 1 , wherein the separation treatment in step (f) produces a heavy residual fraction of which 80 wt % has a boiling point above 370° C. 
     
     
         9 . A process according to  claim 1 , wherein in the separation treatment in step (f) also produces a fuel gas fraction having a portion of renewable origin. 
     
     
         10 . A process according to  claim 1 , wherein at least part of the asphaltic product as obtained in step (a) is subjected to a gasification step (h) to obtain hydrogen having a portion of renewable origin and carbon monoxide.