US 11,939,527 B1
Circular economy for plastic waste to polyethylene via refinery FCC feed pretreater and FCC units
Hye-Kyung Timken, Albany, CA (US); and Cameron McCord, San Ramon, CA (US)
Assigned to Chevron U.S.A. Inc., San Ramon, CA (US)
Filed by Chevron U.S.A. Inc., San Ramon, CA (US)
Filed on Oct. 30, 2022, as Appl. No. 18/051,003.
Application 18/051,003 is a continuation of application No. 17/131,928, filed on Dec. 23, 2020, granted, now 11,566,182.
Claims priority of provisional application 63/002,053, filed on Mar. 30, 2020.
This patent is subject to a terminal disclaimer.
Int. Cl. C10B 53/07 (2006.01); C10G 9/36 (2006.01); C10G 51/02 (2006.01); C10G 51/04 (2006.01); C10G 57/02 (2006.01); C10G 73/02 (2006.01)
CPC C10B 53/07 (2013.01) [C10G 9/36 (2013.01); C10G 51/023 (2013.01); C10G 57/02 (2013.01); C10G 73/02 (2013.01); C10G 2300/1003 (2013.01); C10G 2400/04 (2013.01); C10G 2400/06 (2013.01); C10G 2400/20 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A continuous process for converting waste plastic into recycle for ethylene production comprising:
(a) selecting waste plastics containing polyethylene and/or polypropylene wherein the waste plastics selected contain less than 5 wt % polyethylene terephthalate and polyvinyl chloride;
(b) passing the waste plastics from (a) through a pyrolysis reactor to thermally crack at least a portion of the polyethylene and/or polypropylene to produce a pyrolyzed effluent;
(c) separating the pyrolyzed effluent into offgas, char, and a pyrolysis oil, wherein the pyrolysis oil comprises naphtha and diesel fraction and a heavy fraction comprising hydrocarbons boiling at a temperature higher than 700° F. the heavy fraction optionally comprising wax;
(d) passing the pyrolysis oil from (c) to a refinery FCC feed pretreater unit to obtain a pretreated pyrolysis oil;
(e) passing a FCC feed stream comprising vacuum gas oil (VGO) to a refinery FCC unit;
(f) passing the pretreated pyrolysis oil from (d) to the refinery FCC unit, wherein a flow of the pretreated pyrolysis oil to the refinery FCC unit is up to but no more than 20 volume % of total hydrocarbon flow to the refinery FCC unit;
(g) recovering a gasoline fraction from the refinery FCC unit and passing the recovered gasoline fraction to a gasoline pool;
(h) recovering a liquid petroleum gas C3 olefin/paraffin mixture fraction from the refinery FCC unit; and
(i) passing the liquid petroleum gas C3 olefin/paraffin mixture fraction to a steam cracker for ethylene production.