Purification tank for decoloring regenerated DMT
By using a hydrogen peroxide collector and release tube in the regenerated DMT purification tank, combined with the design of a heater, the problem of dye removal in the regenerated DMT purification process was solved, the purity was improved and condensation or sublimation was avoided, and a highly efficient oxidative decolorization effect was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-10
- Publication Date
- 2026-03-13
AI Technical Summary
Existing purification methods for regenerated DMT are difficult to effectively remove dyes, resulting in low purity and a tendency for localized clumping and sublimation.
Hydrogen peroxide is used to decolorize the regenerated DMT after distillation. By setting up a hydrogen peroxide collector and release pipe, combined with bottom and side heaters, uniform heating and mixing are ensured. A vapor release plate is used to heat the mixed liquid to the optimal oxidation temperature.
It improves the purity of regenerated DMT, avoids localized coagulation or sublimation, enhances oxidation efficiency, and achieves effective removal of staining substances.
Smart Images
Figure CN121648855A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of polyester chemical recycling technology, specifically to a purification tank for regenerating DMT. Background Technology
[0002] Polyethylene terephthalate (PET) is commonly used in textiles, plastic bottles, and food packaging. However, with the widespread use of PET, the pollution problem caused by waste PET is becoming increasingly serious. Currently, there are physical and chemical recycling methods for waste polyester textiles. Compared to physical methods, chemical recycling produces recycled polyester of higher quality with better product performance. However, chemical recycling also generates more byproducts and oligomers, resulting in lower purity of the recovered DMT. Furthermore, most PET products contain dyes added during production, and these dyes are carried into the final product after depolymerization. Therefore, achieving effective decolorization of chemically recycled waste polyester is a pressing issue in polyester recycling.
[0003] In existing technologies, DMT regeneration primarily employs physical methods such as filter cotton for filtration and purification. However, DMT is a unique material; above 141°C, it is a highly fluid liquid but also exhibits sublimation. Below 140°C, it rapidly solidifies and condenses into lumps. Therefore, existing DMT purification methods are ineffective at removing staining substances and are prone to localized clumping and sublimation, all of which negatively impact the purification quality. Summary of the Invention
[0004] In view of the above problems, this application provides a purification vessel for decolorizing regenerated DMT to solve the technical problem that regenerated DMT is not easy to decolorize.
[0005] To achieve the above objectives, this application provides a purification tank for decolorizing regenerated DMT. The purification tank is connected to the discharge pipe of a distillation vessel via a pipeline, and the distillation vessel is connected to the DMT discharge pipe of an ester exchange vessel. The distillation vessel is used to distill the regenerated DMT, and the purification tank is used to inject hydrogen peroxide to decolorize the distilled regenerated DMT. The purification tank includes:
[0006] The tank body is provided with a DMT feed pipe and a hydrogen peroxide feed pipe at the top, and a bottom heater and a side heater are provided inside the tank body; the bottom heater and the side heater are used to heat the regenerated DMT at the bottom and sides of the tank body to keep the regenerated DMT in a liquid state;
[0007] A heating and mixing device is located in the middle of the tank and is used to mix and heat the immiscible regenerated DMT and hydrogen peroxide, so that the dyeing material attached to the regenerated DMT is oxidized and decolorized; the heating and mixing device includes: a stirring shaft, a hydrogen peroxide collector, a hydrogen peroxide release pipe and a vapor release plate.
[0008] The hydrogen peroxide collector is a hollow float-type structure. It floats on the surface of the mixed solution of regenerated DMT and hydrogen peroxide within the tank and is hinged to the stirring shaft via a first hinge, allowing the collector to rotate synchronously with the shaft to collect the hydrogen peroxide solution on the upper layer of the mixed solution. The collector includes multiple sub-collectors, each with a hydrogen peroxide inlet and connected in series via flexible pipes. The sub-collector closest to the stirring shaft is hinged to it via the first hinge, and adjacent sub-collectors are sequentially hinged via second hinges, allowing each sub-collector to adaptively swing up and down as the horizontal angle of the liquid surface changes.
[0009] The stirring shaft is arranged along the central axis of the tank, and a plurality of first stirring blades and a plurality of second stirring blades corresponding to the first stirring blades are spaced apart along the axial direction; each first stirring blade and the corresponding second stirring blade are spirally coiled around the outer periphery of the stirring shaft along the axial direction, and the front end of the first stirring blade is coiled at more than 90 degrees to face the back of the second stirring blade.
[0010] The hydrogen peroxide release pipe is mounted on the stirring shaft and rotates synchronously with it. It is located between the front end of the first stirring blade and the back of the second stirring blade. The hydrogen peroxide release pipe is connected to the hydrogen peroxide collector via a pipe. A high-pressure water pump is installed inside the hydrogen peroxide release pipe, and multiple hydrogen peroxide release holes are provided on its surface. The high-pressure water pump is used to increase the collected hydrogen peroxide solution to form a high-pressure jet that is sprayed out from the hydrogen peroxide release holes, so as to mix the hydrogen peroxide solution with the regenerated DMT.
[0011] The vapor release plate is fixedly installed on the back of the second stirring blade and is used to release high-temperature vapor to heat the mixed liquid at the location of the hydrogen peroxide release pipe, so that the mixed liquid reaches the optimal oxidation temperature.
[0012] Furthermore, the stirring spindle has a first channel and a second channel arranged along its axis inside; the bottom of the first channel is connected to the hydrogen peroxide release pipe, and the top of the first channel is connected to the hydrogen peroxide collector via a hose; the bottom of the second channel is connected to the vapor release plate, and the top of the second channel is connected to the vapor input pipe via a rotary joint.
[0013] Furthermore, the optimal oxidation temperature is higher than the volatilization temperature of the regenerated DMT and lower than the boiling point temperature of the hydrogen peroxide.
[0014] Furthermore, the back of the second stirring blade is provided with multiple steam release plates at radial intervals, and each steam release plate is provided with multiple steam release holes; the steam release plates are spiral plate-shaped structures with the same spiral parameters as the back of the second stirring blade.
[0015] Furthermore, the bottom of the stirring spindle is connected to a stirring motor via a transmission assembly, and the rotational speed of the stirring spindle is less than 100 revolutions per minute.
[0016] Furthermore, the tank is a double-walled insulated tank.
[0017] Furthermore, a DMT discharge pipe is provided at the bottom of the tank.
[0018] Furthermore, the lower surface of the second stirring blade, away from the stirring main shaft, is provided with a side wing, which extends downward along the axial direction.
[0019] Unlike existing technologies, the above-mentioned technical solution uses hydrogen peroxide to decolorize the regenerated DMT after distillation, which can effectively oxidize the staining substances attached to the regenerated DMT and improve the purity of the regenerated DMT. In this technical solution, a hydrogen peroxide collector and a hydrogen peroxide release pipe are provided. These collect the hydrogen peroxide solution located on the upper layer of the mixed solution and remix it back into the mixed solution in the middle of the tank, ensuring thorough mixing of the immiscible regenerated DMT and hydrogen peroxide solution, thus improving the oxidation efficiency of the oxidation contact area of the regenerated DMT. Furthermore, in this embodiment, bottom heaters and side heaters are provided at the bottom and sides of the tank to uniformly heat the regenerated DMT inside the tank, preventing local condensation or sublimation. In this embodiment, a vapor release plate is provided on the back of the second stirring blade to heat the mixed liquid at the location of the hydrogen peroxide release pipe, bringing the mixed liquid to the optimal oxidation temperature. Therefore, while preventing DMT condensation or sublimation, the purification effect of the regenerated DMT can be further improved.
[0020] The above description of the invention is merely an overview of the technical solution of this application. In order to enable those skilled in the art to better understand the technical solution of this application and to implement it based on the description and drawings, and to make the above-mentioned objectives and other objectives, features and advantages of this application easier to understand, the following description is provided in conjunction with the specific embodiments and drawings of this application. Attached Figure Description
[0021] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of specific embodiments of the present invention and other related contents, and should not be considered as limitations on this application.
[0022] In the accompanying drawings of the instruction manual:
[0023] Figure 1 This is a schematic diagram of the recycling equipment for regenerated DMT as described in a specific embodiment;
[0024] Figure 2 This is a schematic diagram of the purification tank used to purify regenerated DMT according to a specific embodiment;
[0025] Figure 3 for Figure 2 A magnified view of part A in the middle;
[0026] Figure 4 for Figure 2 A magnified view of part B in the middle section;
[0027] The reference numerals used in the above figures are explained as follows:
[0028] 1. Alcohololysis vessel; 2. Filter; 3. Ester exchange vessel; 4. Distillation vessel; 5. Purification tank; 6. Recovery device;
[0029] 51. Tank body; 52. DMT feed pipe; 53. DMT discharge pipe; 54. Stirring shaft; 541. Hydrogen peroxide collector; 542. First stirring blade; 543. Hydrogen peroxide release pipe; 544. Second stirring blade; 545. Vapor release plate; 546. Side wing plate; 547. Stirring motor;
[0030] 5410, Sub-collector; 5411, Hydrogen peroxide inlet port; 5412, Hoses; 5413, First hinge; 5414, Mounting base; 5415, Second hinge;
[0031] 5431, hydrogen peroxide release port; 5451, vapor release port;
[0032] 55. Bottom heater; 56. Side heater; 57. Hydrogen peroxide feed pipe; Detailed Implementation
[0033] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.
[0034] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.
[0035] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.
[0036] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.
[0037] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.
[0038] Without further limitations, the use of terms such as “comprising,” “including,” “having,” or other similar open-ended expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.
[0039] As understood in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.
[0040] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0041] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0042] Please see Figures 1 to 4 This embodiment provides a purification tank for decolorizing regenerated DMT. This purification tank is used to purify regenerated DMT obtained from waste PET recycling, thereby decolorizing the regenerated DMT and improving its purity.
[0043] The recycled DMT is obtained through a chemical recycling method, such as... Figure 1 As shown, waste PET undergoes depolymerization in an alcoholysis reactor 1, followed by filtration in a filter 2, then transesterification in an ester exchange reactor 3, and finally distillation in a distillation reactor 4. The resulting regenerated DMT is then sent to a purification tank 5 for purification to remove any dyeing substances adhering to the regenerated DMT. The ester exchange reactor 3 includes a DMT outlet and other product outlets. The DMT outlet is connected to the distillation reactor 4, while the other product outlets are connected to a recovery device 6, which recovers methanol and other substances remaining after the ester exchange.
[0044] like Figure 2 As shown, in this embodiment, the purification tank for decolorizing regenerated DMT uses hydrogen peroxide to oxidize the dyeing material attached to the regenerated DMT, thereby removing the dyeing material attached to the regenerated DMT through oxidation and improving the purity of the regenerated DMT.
[0045] The purification tank for regenerating DMT and decolorizing includes a tank body 51 and a heating and mixing device disposed within the tank body 51. A DMT inlet pipe 52 and a hydrogen peroxide inlet pipe 57 are disposed at the top of the tank body 51. A bottom heater 55 and a side heater 56 are disposed inside the tank body 51; a DMT outlet pipe 53 is disposed at the bottom of the tank body 51. The bottom heater 55 and the side heater 56 are used to heat the regenerated DMT at the bottom and sides of the tank body 51 to keep the regenerated DMT in a liquid state. To reduce heat loss from the tank body 51, the tank body 51 is a double-layered insulated tank.
[0046] A heating and mixing device is located in the middle of the tank 51. The heating and mixing device is used to mix and heat the immiscible regenerated DMT and hydrogen peroxide, so that the dyeing material attached to the regenerated DMT is oxidized and decolorized. The heating and mixing device includes: a stirring shaft 54, a hydrogen peroxide collector 541, a hydrogen peroxide release pipe 543, and a vapor release plate 545.
[0047] The hydrogen peroxide collector 541 is a hollow float-type structure. It floats on the surface of the mixed solution of regenerated DMT and hydrogen peroxide within the tank 51 and is hinged to the stirring shaft 54 via a first hinge 5413. This allows the hydrogen peroxide collector 541 to rotate synchronously with the stirring shaft 54 to collect the hydrogen peroxide solution located on the upper layer of the mixed solution. The hydrogen peroxide collector includes multiple sub-collectors 5410, each equipped with a hydrogen peroxide inlet 5411 and connected in series via flexible pipes. The sub-collector 5410 closest to the stirring shaft 54 is hinged to the stirring shaft 54 via the first hinge 5413, and adjacent sub-collectors 5410 are sequentially hinged via second hinges 5415, allowing each sub-collector 5410 to adaptively swing up and down as the horizontal angle of the liquid surface changes. Because the liquid level is lowest in the middle of the tank during stirring, the height of the sub-collectors closest to the stirring shaft is also the lowest. Therefore, the hydrogen peroxide solution collected in each sub-collector flows to the sub-collector closest to the stirring shaft under the influence of gravity, and then flows through hose 5142 to the hydrogen peroxide release pipe. Figure 2 As shown, the first hinge is fixedly mounted on the stirring shaft via an annular mounting base 5414. The stirring shaft 54 rotates circumferentially in the clockwise direction indicated by arrow W, therefore each sub-collector also rotates clockwise around the direction indicated by arrow W. Furthermore, during rotation, the hydrogen peroxide collector 541 and each sub-collector 5410 therein can oscillate around the first hinge 5413 and the second hinge 5415 in the vertical direction indicated by arrow H. Figure 2 and Figure 3As shown, each pair of adjacent sub-collectors 5410 is hinged to each other by a second hinge 5415. The second hinge 5415 allows each hinged sub-collector 5410 to swing only in the vertical direction indicated by arrow H, so that each sub-collector 5410 can adapt to the horizontal angle of the liquid surface at its position and can rotate together with the stirring shaft 54, so that each sub-collector 5410 is in the optimal collection posture.
[0048] like Figure 2 and Figure 4 As shown, the stirring shaft 54 is arranged along the central axis of the tank 51, and a plurality of first stirring blades 542 and a plurality of second stirring blades 544 corresponding one-to-one with the first stirring blades 542 are arranged at intervals along the axial direction. Each first stirring blade 542 and the corresponding second stirring blade 544 are spirally coiled around the outer periphery of the stirring shaft 54 along the axial direction, and the front end of the first stirring blade 542 is coiled at more than 90 degrees to face the back of the second stirring blade 544. A side wing 546 is provided on the lower surface of the second stirring blade 544 away from the outer side of the stirring shaft 54, and the side wing 546 extends downward along the axial direction. The bottom of the stirring shaft 54 is connected to the stirring motor 547 through a transmission assembly, and the rotation speed of the stirring shaft 54 is less than 100 rpm. The transmission assembly can be a drive shaft assembly, a chain drive assembly, etc. Preferably, the rotation speed of the stirring shaft 54 is 60-80 rpm.
[0049] The hydrogen peroxide release pipe 543 is mounted on the stirring shaft 54 and rotates synchronously with it. It is located between the front end of the first stirring blade 542 and the back of the second stirring blade 544. The hydrogen peroxide release pipe 543 is connected to the hydrogen peroxide collector 541 via a pipe. A high-pressure water pump is installed inside the hydrogen peroxide release pipe 543, and multiple hydrogen peroxide release holes 5431 are provided on its surface. The high-pressure water pump is used to increase the collected hydrogen peroxide solution, forming a high-pressure jet that is ejected from the hydrogen peroxide release holes 5431, thereby mixing the hydrogen peroxide solution with the regenerated DMT. The vapor release plate 545 is fixedly mounted on the back of the second stirring blade 544 and is used to release high-temperature vapor to heat the mixed liquid at the location of the hydrogen peroxide release pipe 543, bringing the mixed liquid to the optimal oxidation temperature. The optimal oxidation temperature is higher than the volatilization temperature of the regenerated DMT and lower than the boiling point temperature of hydrogen peroxide. Specifically, the boiling point of hydrogen peroxide is 150.2 degrees Celsius, and the optimal oxidation temperature is 144-149 degrees Celsius. At the optimal oxidation temperature, part of the regenerated DMT at the location of the vapor release sheet 545 will be vaporized into a gaseous state. In this state, the hydrogen peroxide solution comes into contact with the partially vaporized regenerated DMT, thereby increasing the oxidation contact area and the oxidation effect on the dyeing material.
[0050] In this embodiment, the hydrogen peroxide release tube 543 is positioned between the front end of the first stirring blade 542 and the back of the second stirring blade 544 to ensure that the released hydrogen peroxide solution mixes better with the regenerated DMT. Furthermore, the vapor release plate 545 is fixedly positioned on the back of the second stirring blade 544 to ensure that the regenerated DMT at that location is already at its optimal reaction temperature before the hydrogen peroxide solution is released, thus allowing the hydrogen peroxide solution to oxidize the dyeing material adhering to the regenerated DMT with optimal efficiency as soon as it is released.
[0051] In this embodiment, tank 51 is a container for the oxidation reaction of regenerated DMT and hydrogen peroxide. A DMT inlet pipe 52 and a hydrogen peroxide inlet pipe 57 are provided at the top of tank 51. The DMT inlet pipe 52 is connected to the distillation vessel 4, and the distilled regenerated DMT is injected into tank 51 through the DMT inlet pipe 52. The temperature of the regenerated DMT is greater than 140 degrees Celsius, and the regenerated DMT is in a flowable liquid state. The hydrogen peroxide inlet pipe 57 is used to add hydrogen peroxide solution into tank 51. The hydrogen peroxide solution and the regenerated DMT are mixed and oxidized within tank 51. To maintain the regenerated DMT in a flowable liquid state, this embodiment includes a bottom heater 55 and a side heater 56, which can be PTC heaters. When the stirring shaft 54 rotates, the mixed solution in the middle of tank 51 is agitated by the stirring shaft 54 and moved towards the bottom of tank 51, then from the bottom outwards, and upwards along the outer wall of tank 51. Therefore, the mixed solution flows through the bottom heater 55 and the side heater 56 for heating, thereby maintaining the temperature of the mixed solution above 140 degrees Celsius and below 150 degrees Celsius. The bottom heater 55 and the side heater 56 reduce localized overheating and sublimation of the regenerated DMT.
[0052] Since regenerated DMT and hydrogen peroxide are immiscible, some hydrogen peroxide solution will separate and float to the top of the mixed solution. In this embodiment, each sub-collector 5410 in the hydrogen peroxide collector 541 floats on the surface of the mixed solution and rotates with the stirring shaft 54, thus collecting the upper layer of hydrogen peroxide solution and transporting it through a pipeline to the hydrogen peroxide release pipe 543. Then, it is pressurized by a high-pressure water pump, thereby forming a high-pressure jet that is injected into the mixed solution from the hydrogen peroxide release hole 5431, so that the hydrogen peroxide solution can again oxidize the dyeing material on the surface of the regenerated DMT.
[0053] Therefore, in related technologies, hydrogen peroxide cannot be used to decolorize regenerated DMT. In this embodiment, a hydrogen peroxide collector 541, a hydrogen peroxide release pipe 543, and a vapor release plate 545 are provided on the stirring shaft 54 of the tank 51. This effectively collects the stratified hydrogen peroxide solution inside the tank 51 and remixes it with the regenerated DMT in the middle of the tank 51 through the hydrogen peroxide release pipe 543 in a high-pressure jet manner, allowing it to undergo an oxidation reaction with the dyeing material.
[0054] In this embodiment, the hydrogen peroxide solution collected by the hydrogen peroxide collector 541 and the high-temperature steam used by the vapor release plate 545 are both transported through the interior of the stirring shaft 54, thus reducing the need for additional external piping. The stirring shaft 54 has a first channel and a second channel arranged along its axis inside. The bottom of the first channel communicates with the hydrogen peroxide release pipe 543, and the top of the first channel is connected to the hydrogen peroxide collector 541 via a flexible hose 5412. The bottom of the second channel is connected to the vapor release plate 545, and the top of the second channel is connected to the vapor input pipe via a rotary joint.
[0055] like Figure 4 As shown, in this embodiment, the back of the second stirring blade 544 is provided with multiple vapor release plates 545 arranged radially at intervals, and each vapor release plate 545 is provided with multiple vapor release holes 5451; the vapor release plate 545 is a spiral plate-shaped structure with the same spiral parameters as the back of the second stirring blade 544. That is, the spiral curvature of the vapor release plate 545 is the same as that of the back of the second stirring blade 544, so that the vapor release plate 545 can be completely fitted and fixed to the back of the second stirring blade 544.
[0056] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.
Claims
1. A purification vessel for regenerating and decolorizing DMT, characterized in that, The purification tank is connected to the discharge pipe of the distillation vessel via a pipeline, and the distillation vessel is connected to the DMT discharge pipe of the transesterification vessel; the distillation vessel is used to distill the regenerated DMT, and the purification tank is used to inject hydrogen peroxide to decolorize the distilled regenerated DMT; the purification tank includes: The tank body is provided with a DMT feed pipe and a hydrogen peroxide feed pipe at the top, and a bottom heater and a side heater are provided inside the tank body; the bottom heater and the side heater are used to heat the regenerated DMT at the bottom and sides of the tank body to keep the regenerated DMT in a liquid state; A heating and mixing device is located in the middle of the tank and is used to mix and heat the immiscible regenerated DMT and hydrogen peroxide, so that the dyeing material attached to the regenerated DMT is oxidized and decolorized; the heating and mixing device includes: a stirring shaft, a hydrogen peroxide collector, a hydrogen peroxide release pipe and a vapor release plate. The hydrogen peroxide collector is a hollow float-type structure. It floats on the surface of the mixed solution of regenerated DMT and hydrogen peroxide within the tank and is hinged to the stirring shaft via a first hinge, allowing the collector to rotate synchronously with the shaft to collect the hydrogen peroxide solution on the upper layer of the mixed solution. The collector includes multiple sub-collectors, each with a hydrogen peroxide inlet and connected in series via flexible pipes. The sub-collector closest to the stirring shaft is hinged to it via the first hinge, and adjacent sub-collectors are sequentially hinged via second hinges, allowing each sub-collector to adaptively swing up and down as the horizontal angle of the liquid surface changes. The stirring shaft is arranged along the central axis of the tank, and a plurality of first stirring blades and a plurality of second stirring blades corresponding to the first stirring blades are spaced apart along the axial direction; each first stirring blade and the corresponding second stirring blade are spirally coiled around the outer periphery of the stirring shaft along the axial direction, and the front end of the first stirring blade is coiled at more than 90 degrees to face the back of the second stirring blade. The hydrogen peroxide release pipe is mounted on the stirring shaft and rotates synchronously with it. It is located between the front end of the first stirring blade and the back of the second stirring blade. The hydrogen peroxide release pipe is connected to the hydrogen peroxide collector via a pipe. A high-pressure water pump is installed inside the hydrogen peroxide release pipe, and multiple hydrogen peroxide release holes are provided on its surface. The high-pressure water pump is used to increase the collected hydrogen peroxide solution to form a high-pressure jet that is sprayed out from the hydrogen peroxide release holes, so as to mix the hydrogen peroxide solution with the regenerated DMT. The vapor release plate is fixedly installed on the back of the second stirring blade and is used to release high-temperature vapor to heat the mixed liquid at the location of the hydrogen peroxide release pipe, so that the mixed liquid reaches the optimal oxidation temperature.
2. The purification vessel for regenerating DMT decolorization according to claim 1, characterized in that, The stirring spindle has a first channel and a second channel arranged along its axis inside; the bottom of the first channel is connected to the hydrogen peroxide release pipe, and the top of the first channel is connected to the hydrogen peroxide collector through a hose; the bottom of the second channel is connected to the vapor release plate, and the top of the second channel is connected to the vapor input pipe through a rotary joint.
3. The purification vessel for regenerating DMT and decolorizing according to claim 1, characterized in that, The optimal oxidation temperature is higher than the volatilization temperature of the regenerated DMT and lower than the boiling point temperature of the hydrogen peroxide.
4. The purification vessel for regenerating DMT decolorization according to claim 1, characterized in that, The back of the second stirring blade is provided with multiple steam release plates arranged radially at intervals, and each steam release plate is provided with multiple steam release holes; the steam release plate is a spiral plate structure with the same spiral parameters as the back of the second stirring blade.
5. The purification vessel for regenerating DMT decolorization according to claim 1, characterized in that, The bottom of the stirring spindle is connected to the stirring motor via a transmission assembly, and the rotation speed of the stirring spindle is less than 100 revolutions per minute.
6. The purification vessel for regenerating DMT decolorization according to claim 1, characterized in that, The tank is a double-walled insulated tank.
7. The purification vessel for regenerating DMT decolorization according to claim 1, characterized in that, The bottom of the tank is equipped with a DMT discharge pipe.
8. The purification vessel for regenerating DMT decolorization according to claim 1, characterized in that, The second stirring blade has a side wing on its lower surface on the outer side away from the stirring main shaft, and the side wing extends downward along the axial direction.