Integrated process for upgrading middle distillate production
First Claim
Patent Images
1. A process for hydrotreating a petroleum feedstock comprising the steps of:
- (a) catalytically hydrocracking a petroleum feedstock in the presence of hydrogen at a pressure ranging from 5 to 21 MPa;
(b) cooling and separating effluent from the hydrocracking step (a) into vapor and liquid streams;
(c) recycling the vapor stream from step (b) to the hydrocracking step (a);
(d) distilling the liquid stream from step (b) in a fractionation column into petroleum distillate streams including first and second middle distillate streams characterized by a bubble point temperature ranging from about 177°
C. to about 357°
C. and an API density at 15°
C. ranging from about 30°
to about 45°
;
(e) catalytically hydrotreating the first middle distillate stream from step (d) in the presence of hydrogen;
(f) separating effluent from the hydrotreatment step (e) into a vapor stream containing hydrogen and a liquid stream essentially free of hydrogen;
(g) recycling the hydrogen-containing vapor stream from step (f) to the hydrocracking step (a); and
(h) steam stripping the liquid stream from step (f) with the second middle distillate stream from step (d), in a side stripping column integrated with the fractionation column in distilling step (d) to return overhead vapor from the side stripping column to the fractionation column, to form an upgraded middle distillate product stream.
2 Assignments
0 Petitions
Accused Products
Abstract
An integrated middle distillate upgrading process and unit are disclosed. A middle distillate side-stream of a conventional single stage hydrocracking process is circulated to a hydrotreating stage such as an aromatics saturation reactor and/or a catalytic dewaxing reactor to effect middle distillate upgrade. The upgraded product is then finished in a fractionation stage side-stripper column. The integrated hydrotreating reactor can share the duty of existing hydrocracker stage equipment and take advantage of existing process heat to eliminate the need for much of the equipment generally required by a stand-alone hydrotreating reactor of the prior art.
-
Citations
8 Claims
-
1. A process for hydrotreating a petroleum feedstock comprising the steps of:
-
(a) catalytically hydrocracking a petroleum feedstock in the presence of hydrogen at a pressure ranging from 5 to 21 MPa; (b) cooling and separating effluent from the hydrocracking step (a) into vapor and liquid streams; (c) recycling the vapor stream from step (b) to the hydrocracking step (a); (d) distilling the liquid stream from step (b) in a fractionation column into petroleum distillate streams including first and second middle distillate streams characterized by a bubble point temperature ranging from about 177°
C. to about 357°
C. and an API density at 15°
C. ranging from about 30°
to about 45°
;(e) catalytically hydrotreating the first middle distillate stream from step (d) in the presence of hydrogen; (f) separating effluent from the hydrotreatment step (e) into a vapor stream containing hydrogen and a liquid stream essentially free of hydrogen; (g) recycling the hydrogen-containing vapor stream from step (f) to the hydrocracking step (a); and (h) steam stripping the liquid stream from step (f) with the second middle distillate stream from step (d), in a side stripping column integrated with the fractionation column in distilling step (d) to return overhead vapor from the side stripping column to the fractionation column, to form an upgraded middle distillate product stream. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
Specification