US 12,325,832 B2
Method of producing pyrolysis products from a mixed plastics stream and integration of the same in a refinery
Omer Refa Koseoglu, Dhahran (SA); and Gerard De Nazelle, Dhahran (SA)
Assigned to Saudi Arabian Oil Company, Dhahran (SA)
Filed by Saudi Arabian Oil Company, Dhahran (SA)
Filed on Jun. 23, 2021, as Appl. No. 17/355,718.
Prior Publication US 2023/0013013 A1, Jan. 19, 2023
Int. Cl. C10G 65/06 (2006.01); C10G 1/10 (2006.01); C10G 7/06 (2006.01); C10G 35/00 (2006.01); C10G 45/08 (2006.01); C10G 45/36 (2006.01); C10G 65/16 (2006.01)
CPC C10G 65/16 (2013.01) [C10G 1/10 (2013.01); C10G 7/06 (2013.01); C10G 35/00 (2013.01); C10G 45/08 (2013.01); C10G 45/36 (2013.01); C10G 65/06 (2013.01); C10G 2300/1003 (2013.01); C10G 2300/301 (2013.01); C10G 2300/4006 (2013.01); C10G 2300/4056 (2013.01); C10G 2400/04 (2013.01); C10G 2400/06 (2013.01); C10G 2400/30 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method of producing pyrolysis products from a mixed plastics stream, the method comprising:
(a) conducting pyrolysis of a plastic feedstock to produce a stream of plastic pyrolysis oil;
(b) feeding the plastic pyrolysis oil to a first fractionator to separate the plastic pyrolysis oil into a distillate fraction including naphtha and diesel boiling in the range of 36 to 370° C. and a vacuum gas oil fraction comprising hydrocarbons boiling above 370° C.; and
(c) feeding the distillate fraction to a three step hydrotreating operation, the three step hydrotreating operation comprising:
i. feeding the distillate fraction comprising naphtha and diesel boiling in the range of 36 to 370° C. to a first hydrotreating unit configured and operated to remove di-olefins by hydrogenation from the distillate fraction to produce a first product stream of dediolefinized plastic pyrolysis distillate representing all the effluent from the first hydrotreating unit, wherein the first hydrotreating unit is operated at a temperature of 150 to 210° C. and the first product stream of dediolefinized plastic pyrolysis distillate comprises less than 1 wt. % di-olefins;
ii. feeding the first product stream directly and entirely and without additional hydrocarbons to a second hydrotreating unit configured and operated to remove mono-olefins by hydrogenation from the first product stream to produce a second product stream of deolefinized plastic pyrolysis distillate, wherein the second hydrotreating unit is operated at a temperature of 300 to 330° C. and the second product stream of deolefinized plastic pyrolysis distillate comprises less than 1 wt. % olefins; and
iii. feeding the second product stream to a third hydrotreating unit configured and operated to remove sulfur by hydrodesulfurization and nitrogen by hydrodenitrogenation from the second product stream to produce a third product stream of clean plastic pyrolysis distillate, wherein the third hydrotreating unit is operated at a temperature of 330 to 420° C.