US-12617923-B2 - Chemical recycling of colored plastics mixtures

Abstract

A method of recycling plastic waste by feeding a quantity of a PET-containing reclaimer colored plastic-containing mixture and/or MRF colored plastic-containing mixture separated from the plastic waste to a chemical recycling facility; and depolymerizing in the chemical recycling facility at least a portion of the PET-containing reclaimer colored plastic-containing mixture and/or MRF colored plastic-containing mixture, and further feeding at least a portion of the quantity of colored plastic-containing mixture to at least one density separation stage before depolymerizing, thereby producing a PET-enriched stream that is fed into a solvolysis facility within the chemical recycling facility, and wherein the solvolysis facility is a methanolysis facility.

Inventors

• Bruce Roger DeBruin
• Michael Paul Ekart
• Anne-Martine Sherbeck Jackson
• Nathan Mitchell West
• Zhufang Liu

Assignees

• EASTMAN CHEMICAL COMPANY

Dates

Publication Date

20260505

Application Date

20210413

Claims (9)

1. 1 . A method of recycling a plastic waste comprising: (a) feeding a quantity of a PET-containing reclaimer colored plastic-containing mixture and/or MRF colored plastic-containing mixture separated from said plastic waste to a chemical recycling facility; and (b) depolymerizing in said chemical recycling facility at least a portion of said PET-containing reclaimer colored plastic-containing mixture and/or MRF colored plastic-containing mixture, further comprising feeding at least a portion of said quantity of colored plastic-containing mixture to at least one density separation stage before said depolymerizing (b), thereby producing a PET-enriched stream that is fed into a solvolysis facility within said chemical recycling facility, wherein the solvolysis facility is a methanolysis facility.
2. 2 . The method of claim 1 , wherein said quantity of colored plastic-containing mixture comprises at least 1 and/or not more than 99.9 weight percent PET on a dry basis.
3. 3 . The method of claim 1 , wherein said quantity of colored plastic-containing mixture comprises at least 1 weight percent non-clear PET on a dry basis.
4. 4 . The method of claim 1 , wherein said quantity of colored plastic-containing mixture comprises not more than 10 weight percent halogens on a dry basis.
5. 5 . The method of claim 1 , wherein said quantity of colored plastic-containing mixture comprises at least 1 weight percent and/or not more than 90 weight percent polyolefins on a dry basis.
6. 6 . The method of claim 1 , wherein said quantity of colored plastic-containing mixture comprises at least 0.1 weight percent non-clear PET and/or other colored plastic material on a dry plastic basis.
7. 7 . The method of claim 1 , wherein said quantity of colored plastic-containing mixture further comprises at least 0.1 weight percent PVC, nylon, and/or copolyesters on a dry basis.
8. 8 . The method of claim 1 , wherein said quantity of colored plastic-containing mixture is fed directly to a solvolysis facility within said chemical recycling facility without undergoing a preprocessing and/or separation process.
9. 9 . The method of claim 1 , wherein said at leas one density separation stage comprises at least two density separation stages.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S) This application is a national stage filing under 35 USC § 371 of International Application Number PCT/US2021/026975, filed on Apr. 13, 2021 which claims the benefit of the filing date to U.S. Provisional Application No. 63/008,914, filed on Apr. 13, 2020, the entire disclosures of which are incorporated by reference herein. BACKGROUND Waste materials, especially non-biodegradable waste materials, can negatively impact the environment when disposed of in landfills after a single use. Thus, from an environmental standpoint, it is desirable to recycle as much waste material as possible. However, there still exist streams of low value waste that are nearly impossible or economically unfeasible to recycle with conventional recycling technologies. In addition, some conventional recycling processes produce waste streams that are themselves not economically feasible to recover or recycle, resulting in additional waste streams that must be disposed of or otherwise handled. For example, plastic reclaimer facilities and municipal recycling facilities can produce significant amounts of waste plastics that are undesirable or unusable by consumers and mechanical recycling facilities. In particular, such facilities can produce quantities of colored plastic-containing mixtures that are undesirable or unusable in their mixture form but may contain some amount of otherwise desirable or usable PET and other plastics. However, these colored plastic-containing mixtures are typically disposed of in landfills and/or incinerators. Thus, a need exists for a large-scale facility capable of chemically recycling a variety of plastic-containing waste materials recovered from such sources, particularly otherwise undesirable or unusable colored plastic-containing mixtures from a plastic reclaimer facility and/or municipal recycling facility, in an economically viable manner. SUMMARY In one aspect, the present technology concerns a method of recycling a plastic waste. Generally, the method comprises: (a) feeding a quantity of PET-containing reclaimer colored plastic-containing mixture and/or MRF colored plastic-containing mixture separated from said plastic waste to a chemical recycling facility; and (b) depolymerizing in the chemical recycling facility the at least a portion of the PET-containing reclaimer colored plastic-containing mixture and/or MRF colored plastic-containing mixture. In one aspect, the present technology concerns the use of a PET-containing colored plastic-containing mixture as a feedstock to a chemical recycling facility. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block flow diagram illustrating the main steps of a process and facility for chemically recycling waste plastic according to embodiments of the present technology; FIG. 2 is a block flow diagram illustrating a separation process and zone for separating mixed plastic waste according to embodiments of the present technology; FIG. 3 is a block flow diagram illustrating the main steps of a process and facility for PET solvolysis according to embodiments of the present technology; FIG. 4 is a block flow diagram illustrating typical rPET products and co-products derived from a PET reclaimer facility; FIG. 5 is a block flow diagram illustrating the main steps of a PET reclaimer process, and the resulting products and co-products produced therefrom; FIG. 6 is a block flow diagram illustrating an exemplary liquification zone of the chemical recycling facility shown in FIG. 1 according to embodiments of the present technology; FIG. 7 is a block flow diagram illustrating the main steps of a pyrolysis process and facility for converting waste plastic into a pyrolyzed product streams according to embodiments of the present technology; FIG. 8A is a block flow diagram illustrating the main steps of an integrated pyrolysis process and facility and a cracking process and facility according to embodiments of the present technology; FIG. 8B is a schematic diagram of a cracking furnace according to embodiments of the present technology; FIG. 9 is a schematic diagram of a POx reactor according to embodiments of the present technology; and FIG. 10 is a schematic diagram illustrating various definitions of the term “separation efficiency” as used herein. DETAILED DESCRIPTION We have discovered new methods and systems for using one or more PET-containing materials from various sources as a feedstock to a chemical recycling facility, and in particular a solvolysis facility. More particularly, we have discovered that PET-containing materials used as feedstock for chemical recycling or solvolysis may include colored plastic-containing mixtures derived from plastic reclaimer facilities and/or municipal recycling facilities. While these colored plastic-containing mixtures are generally considered undesirable or unusable by mechanical recycling facilities, the methods and systems described herein are capable of using such colored plastic-con