# US 2023/0265348 A1 · Method for pyrolysis of waste material in an industrial process > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0265348 A1 - Document ID: US20230265348A1 - Status: Published application - Kind: A1 - Application number: 18/016,296 - Filed: 2021-07-12 - Published: 2023-08-24 - Earliest claimed: 2020-07-17 - Assignees: CCT International, Inc. - Applicants: Cct International - Inventors: Rik VAN MEIRHAEGHE; Johannes Dingenis VAN DER ENDT; Dries PARMENTIER - Web page: https://patentgrep.com/patent/US20230265348A1 ## CPC - C10B 47/44: with conveyor-screws - B29C 48/1472: {at the die nozzle exit zone} - C10B 7/10: with conveyor-screws - C10B 47/32: in ovens with mechanical conveying means - C10B 53/07: {of solid raw materials consisting} of synthetic polymeric materials, e.g. tyres (recovery or working-up of waste materials of organic macromolecular compounds or compositions based thereon by dry-heat treatment for obtaining partially depolymerised materials C08J11/10; production of liquid hydrocarbon mixtures from rubber or rubber waste C10G1/10) - C10B 57/08: Non-mechanical pretreatment of the charge (C10L9/00 takes precedence), {e.g. desulfurization} - C10B 57/10: Drying - C10B 47/34: with rotary scraping devices - Y02P 20/143: the feedstock being recycled material, e.g. plastics - C10B: DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS (cracking oils C10G; underground gasification of minerals E21B43/295) - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A method for pyrolysis of a mass of waste material, includes: providing a screw arrangement adapted to supply heat to the mass by mechanical shear; providing a reactor after the screw arrangement, adapted to supply heat to the mass in the absence of oxygen by heating the reactor wall; heating the mass to an exit temperature and increasing the pressure to an exit pressure in the screw arrangement; thermally degrading the mass in the reactor. The mass is brought into an extreme condition at the exit temperature and exit pressure by the screw arrangement, such that during the pressure drop pyrolysis occurs, thereby forming gaseous hydrocarbons within the connecting element. ## Claims ### Claim at position 1 1-15. (canceled) ### Claim 16 A method for pyrolysis of a mass of waste material, comprising: providing a screw arrangement adapted to supply heat to said mass by mechanical shear; providing a connecting element, connected to the exit of said screw arrangement; providing a reactor after said connecting element, adapted to supply heat to said mass in the absence of oxygen by heating the reactor wall with an external heat source; heating said mass in said screw arrangement to an exit temperature, wherein said mass is at least partially melted; transporting said mass through said connecting element; thermally degrading said mass in said reactor wherein carbon-carbon bonds in said mass are broken by pyrolysis and volatile hydrocarbons are formed, wherein said method further comprises: increasing the pressure of said mass through said screw arrangement, to an exit pressure; expanding said mass in said connecting element, with a pressure drop from said exit pressure to a lower pressure; wherein said mass is brought into an extreme condition at said exit temperature and exit pressure by said screw arrangement, such that during said pressure drop pyrolysis occurs, thereby forming gaseous hydrocarbons within said connecting element. ### Claim 17 (depends on 16) The method according to claim 16, wherein increasing said pressure through said screw arrangement is such that during said heating in said screw arrangement pyrolysis of said mass is avoided, or such that at most 1% mass percentage of the hydrocarbons present in said mass at the entrance of said screw arrangement is converted into gaseous hydrocarbons during said heating in said screw arrangement. ### Claim 18 (depends on 17) The method according to claim 17, wherein said gaseous hydrocarbons released during said heating in said screw arrangement, leave said screw arrangement via one or more outlet ports on said screw arrangement. ### Claim 19 (depends on 16) The method according to claim 16, wherein said method comprises: evacuating water vapor, being released from said mass during said heating in said screw arrangement, via a first outlet port on said screw arrangement; evacuating gases comprising halogens, being released from said mass during said heating in said screw arrangement, via a second outlet port on said screw arrangement; evacuating gaseous hydrocarbons, being released from said mass during said heating in said screw arrangement, via a third outlet port on said screw arrangement. ### Claim 20 (depends on 16) The method according to claim 16, wherein said connecting element provides a direct connection between said screw arrangement and said reactor, and said pressure drop is from said exit pressure to a reactor pressure lower than said exit pressure, or said connecting element provides a connection between said screw arrangement and a buffer tank placed between said screw arrangement and said reactor and said pressure drop is from said exit pressure to a pressure in said buffer tank lower than said exit pressure. ### Claim 21 (depends on 20) The method according to claim 20, wherein said method comprises: transporting said mass through said connecting element, wherein said gaseous hydrocarbons formed during said pressure drop, are carried by said mass flowing towards said reactor or towards said buffer tank. ### Claim 22 (depends on 16) The method according to claim 16, wherein said gaseous hydrocarbons formed in said connecting element during said pressure drop, occur as gas bubbles present within said melted mass. ### Claim 23 (depends on 16) The method according to claim 16, wherein the pressure difference between said exit pressure and said lower pressure causes said mass to flow, thereby transporting said mass through said connecting element. ### Claim 24 (depends on 16) The method according to claim 16, wherein said waste material consists for at least 80% of its mass percentage of PolyEthylene and/or PolyPropylene, and said exit temperature is higher than 330° C. ### Claim 25 (depends on 16) The method according to claim 16, wherein said reactor comprises a reservoir adapted to be filled to a filling level with said mass, wherein inside said reservoir a mixing arrangement is present adapted to mix said mass inside said reservoir, or no said mixing arrangement is present; no arrangement is present for transporting said mass through said reservoir. ### Claim 26 (depends on 25) The method according to claim 25, wherein said reactor is operated alternately in continuous mode and in batch mode, wherein in said continuous mode, mass is continuously fed into said reactor during said thermal degradation, and in said batch mode, no mass is fed into said reactor during said thermal degradation. ### Claim 27 (depends on 16) The method according to claim 16, wherein during said thermal degradation said reactor wall is heated such that inside said reactor a pyrolysis temperature prevails higher than said exit temperature, 50° C. to 150° C. higher than said exit temperature, and wherein said pyrolysis temperature in said reactor is higher during said batch mode than during said continuous mode, 60° C. to 100° C. higher. ### Claim 28 A system for pyrolysis of a mass of waste material, comprising: a screw arrangement adapted to: supply heat to said mass, at least in part by mechanical shear, so that said mass present in said screw arrangement is heated to an exit temperature, wherein said mass is at least partly melted, and to increase the pressure of said mass, to an exit pressure at the exit of said screw arrangement; a connecting element connected to the exit of said screw arrangement; a reactor placed after said connecting element, adapted to supply heat to said mass in the absence of oxygen by heating the reactor wall with an external heat source, so that said mass present in said reactor thermally degrades, whereby carbon-carbon bonds in said mass are broken by pyrolysis and volatile hydrocarbons are formed, wherein said screw arrangement is adapted to bring said mass in an extreme condition at said exit pressure and said exit temperature, such that during an expansion of said mass in said connecting element pyrolysis occurs, thereby forming gaseous hydrocarbons in said connecting element; said screw arrangement comprises three different outlet ports, adapted to evacuate water vapor, gases comprising halogens, and gaseous hydrocarbons from said screw arrangement; said connecting element comprises a closed wall and is adapted to transport said mass comprising gaseous hydrocarbons formed during said expansion, by allowing said mass to flow through said connecting element in presence of said exit pressure. ### Claim 29 (depends on 28) The system according to claim 28, wherein said connecting element comprises one or more pipes, and wherein the inner surface of said one or more pipes is provided with a coating having anti-sticking properties, said coating being adapted to reduce sticking of said mass to said inner surface. ### Claim 30 (depends on 28) The system according to claim 28, wherein said system comprises a measurement adapted to detect gaseous hydrocarbons being released from said mass in said screw arrangement.