Process for PVC-containing mixed plastic waste pyrolysis
AssigneeUop LLC
InventorsPing Sun, Jeffrey Tyska, Joseph A. Montalbano
Life of this patent
Estimating the term…
Abstract
A process for pyrolysis of a mixed plastic stream that contains polyvinyl chloride (PVC) is provided in which the chloride from PVC is removed from an initial melting reactor that heats the mixed plastic stream to a sufficient temperature to produce HCl but at a low enough temperature to avoid production of organochlorides. Chloride is primarily removed in a vapor stream from the initial melting reactor, while additional chloride removal may be removed downstream from the melting reactor by the use of sorbent addition to the pyrolysis reactor and by subsequent adsorbent beds.
Claims18
A process for producing a pyrolysis oil out of a mixed plastic waste stream comprising
- a. sending the mixed plastic waste stream comprising at least two types of plastic including chlorine-containing plastics and other plastics to a melting reactor to produce a first vapor stream and a first liquid stream;
- b. sending said first liquid stream to a pyrolysis reactor to be heated to produce a product comprising vapor, liquid, and solid particles;
- c. withdrawing a second vapor stream, a second liquid stream, and a residue stream comprising the solid particles from said pyrolysis reactor;
- d. circulating a part of the second liquid stream to said melting reactor and sending a part of the second liquid stream to be heated and returned to said pyrolysis reactor as a heated second liquid stream;
- and
- e. cooling and separating the second vapor stream into a third vapor stream and a third liquid stream and then passing the third liquid stream through an adsorbent bed to remove residual chloride to produce said pyrolysis oil.
A process for pyrolysis of a mixed plastic waste stream comprising:
- a. sending the mixed plastic waste stream to a melting reactor to produce a first vapor stream and a first liquid stream;
- b. sending the first liquid stream to a pyrolysis reactor to be heated to produce a product comprising vapor, liquid, and solid particles, wherein the solid particles move in a downward direction within said pyrolysis reactor;
- c. withdrawing a second vapor stream, a second liquid stream, and a residue stream comprising the solid particles from said pyrolysis reactor, wherein a mass ratio between said second vapor stream and said residue stream is 2.3 to 9;
- d. cooling and separating said second vapor stream into a third vapor stream and a third liquid stream and then treating said third liquid stream in at least one adsorbent bed to remove chlorine containing impurities;
- e. mixing a portion of the second liquid stream with the mixed plastic waste stream in the melting reactor providing temperatures needed to produce the first vapor stream;
- and
- f. sending a portion of the second liquid stream to an external heater to produce a heated stream and sending the heated stream back to mix with the first liquid stream before said mixed stream enters said pyrolysis reactor.
A process for pyrolysis of a mixed plastic waste stream comprising:
- a. sending the mixed plastic waste stream to a melting reactor to produce a first vapor stream and a first liquid stream;
- b. sending the first liquid stream to a pyrolysis reactor to be heated to produce a product comprising vapor, liquid, and solid particles, wherein the solid particles move in a downward direction within said pyrolysis reactor;
- c. withdrawing a second vapor stream, a second liquid stream, and a residue stream comprising the solid particles from said pyrolysis reactor;
- d. sending a portion of said second liquid stream to a heat exchanger and recycled to said pyrolysis reactor and sending a second portion of said second liquid stream to said melting reactor;
- and
- e. cooling and separating said second vapor stream into a third vapor stream and a third liquid stream and then treating said third liquid stream in at least one adsorbent bed to remove chlorine containing impurities.
Dependencies are inferred from the claim text.