# US 2020/0399437 A1 · Apparatus and method for mixing recycling material into a polyester melt > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0399437 A1 - Document ID: US20200399437A1 - Status: Published application - Kind: A1 - Application number: 16/969,813 - Filed: 2019-02-19 - Published: 2020-12-24 - Earliest claimed: 2018-02-20 - Assignees: Uhde Inventa-Fischer GmbH; thyssenkrupp AG - Applicants: Uhde Inventa-Fischer GmbH; thyssenkrupp AG - Inventors: Alexander PAWELSKI; Martin HITTORFF; Heinrich KOCH; Christopher HESS - Web page: https://patentgrep.com/patent/US20200399437A1 ## CPC - C08J 11/04: of polymers - C08J 11/24: containing hydroxyl groups - B01F 35/80: Forming a predetermined ratio of the substances to be mixed (controlling ratio of two or more flows of fluid or fluent material G05D11/02) - B01F 35/92: for heating the outside of the receptacle, e.g. heated jackets or burners - B01J 19/0013: {Controlling the temperature of the process} - B01J 19/06: Solidifying liquids (making microcapsules B01J13/02) - B01J 19/245: {placed in series} - C08G 63/183: Terephthalic acids - C08G 63/78: Preparation processes - B01F 2035/99: {Heating} - B01F 2101/2805: {Mixing plastics, polymer material ingredients, monomers or oligomers} - B01J 2219/0004: Processes in series - B01J 2219/00087: with heat exchange elements outside the reactor - C08J 2367/02: Polyesters derived from dicarboxylic acids and dihydroxy compounds; (C08J2367/06 takes precedence) - Y02W 30/62: Plastics recycling; Rubber recycling - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - B01F: MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING (mixing paints B44D3/06) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT ## Abstract Apparatuses and processes may be utilized for mixing used polyester into a polyester melt. In some processes an intermediate product stream is branched off from an intermediate stage in a virgin polyester production process. The intermediate product stream is then mixed with recycled polyester flakes in a dynamic mixer, where not more than 60% of a melting energy required to melt all the recycled polyester flakes is generated and/or supplied in the dynamic mixer. The mixture produced in this way is fed into a subsequent stage downstream of the intermediate stage and converted up to the desired degree of polycondensation. In this way, it is possible to physically reutilize used polyester or polyester waste. ## Claims ### Claim at position 1 1-17. (canceled) ### Claim 18 A process for producing polyester using recycled polyester flakes, the process comprising: branching off an intermediate product stream from an intermediate stage in a virgin polyester production process; mixing the intermediate product stream with recycled polyester flakes in a dynamic mixer to form a mixture, wherein not more than 60% of a melting energy required to melt the recycled polyester flakes is generated and/or supplied; feeding the mixture into a downstream stage downstream of the intermediate stage and/or recycling the mixture into a reaction stage from which the intermediate product stream was taken; and converting the mixture up to a desired level of polycondensation. ### Claim 19 (depends on 18) The process of claim 18 wherein upon entry into the dynamic mixer the recycled polyester flakes have an average temperature of 0 to 200° C. ### Claim 20 (depends on 18) The process of claim 18 comprising supplying the intermediate product stream with at least 40% of the melting energy prior to the mixing, wherein the intermediate product stream transfers less than 40% of the melting energy to the recycled polyester flakes during a dwell time in the dynamic mixer. ### Claim 21 (depends on 18) The process of claim 18 comprising supplying the mixture with at least 40% of the melting energy after the mixing. ### Claim 22 (depends on 18) The process of claim 18 wherein a dwell time of the intermediate product stream and the recycled polyester flakes in the dynamic mixer is not more than 60 seconds. ### Claim 23 (depends on 18) The process of claim 18 wherein the mixing is performed at an absolute pressure of 3 to 100 mbar. ### Claim 24 (depends on 18) The process of claim 18 comprising filtering the mixture prior to attainment of the desired level of polycondensation. ### Claim 25 (depends on 18) The process of claim 18 wherein at least one of: the desired level of polycondensation is 100 to 200, or the mixture converted up to the desired level of polycondensation has an intrinsic viscosity measured according to ASTM D-4603-03 of 0.6 to 0.9 dL/g. ### Claim 26 (depends on 18) The process of claim 18 wherein 10% to 100% of an overall stream is branched off as the intermediate product stream at the intermediate stage. ### Claim 27 (depends on 18) The process of claim 18 wherein the intermediate product stream contains a diol. ### Claim 28 (depends on 18) The process of claim 18 wherein the mixture contains 5% to 60% by weight recycled polyester flakes. ### Claim 29 (depends on 18) The process of claim 18 comprising mixing the intermediate product stream and the recycled polyester flakes in the dynamic mixer with an additive selected from a group consisting of catalysts, stabilizers, dyes, flatting agents, optical brighteners, or mixtures thereof, wherein the additive is used in a proportion of not more than 5% by weight based on a resulting mixture. ### Claim 30 An apparatus for producing polyester using recycled polyester flakes, the apparatus comprising: an apparatus for producing virgin polyester having multiple successive reaction vessels; and a dynamic mixer with a first inlet, a second inlet, and an outlet, wherein the first inlet is connected to a first reaction vessel of the multiple successive reaction vessels, wherein the second inlet is connected to an apparatus for dosage of bulk material, wherein the outlet is connected downstream to a second reaction vessel of the multiple successive reaction vessels. ### Claim 31 (depends on 30) The apparatus of claim 30 comprising an apparatus for comminution of recycled polyester that is connected upstream of the apparatus for dosage of bulk material. ### Claim 32 (depends on 30) The apparatus of claim 30 comprising: a first heat exchanger disposed between the apparatus for comminution of recycled polyester and the apparatus for dosage of bulk material; and a second heat exchanger disposed between the first reaction vessel and the dynamic mixer. ### Claim 33 (depends on 30) The apparatus of claim 30 comprising an apparatus for generating a reduced pressure that is connected to the dynamic mixer.