Production system for continuously producing TPEE by taking DMT as raw material

Abstract

The utility model belongs to the technical field of organic high-molecular compounds, and particularly relates to a production system for continuously producing TPEE (Thermoplastic Polyether Ether) by taking DMT (Dimethyl Terephthalate) as a raw material. The pulping system comprises a pulping system, a stirring system and a control system, wherein the pulping system is used for preparing pulp; the esterification system is connected to the rear end of the pulping system; the preshrinking kettle system is connected to the rear end of the esterification system; the final shrinking kettle system is connected to the rear end of the preshrinking kettle system, and a mixer is arranged at an outlet of the final shrinking kettle system and used for adding auxiliaries. The utility model is used for solving the technical problems of large quality difference and multiple batch numbers of products in the same batch caused by intermittent production in the existing production technology taking DMT as a raw material.

Description

Technical Field

[0001] The utility model belongs to the technical field of organic polymer compounds, and specifically relates to a production system for continuously producing TPEE using DMT as a raw material. Background Art

[0002] At present, there are two main production technologies for TPEE (thermoplastic polyester elastomer):

[0003] 1. Intermittent production of TPEE using DMT (dimethyl terephthalate) as raw material;

[0004] 2. Continuously produce TPEE using PTA (terephthalic acid) as raw material.

[0005] However, the main disadvantage of the first production technology is that it is an intermittent production process, the production process conditions vary greatly, and the time difference between the front and back discharges causes large differences in the quality of products produced in the same batch and multiple batch numbers. Therefore, the second production technology is now the mainstream technology.

[0006] However, with the progress of recycling technology for PET bottles and clothing, the output of DMT has also increased year by year, and it is imperative to use DMT as the main raw material to replace PTA. So, how to overcome the defects of the existing production technology using DMT as raw material has become an urgent problem to be solved. Utility Model Content

[0007] The technical problem to be solved by the utility model is to overcome the shortcomings of the prior art and provide a production system for continuously producing TPEE using DMT as a raw material, so as to solve the technical problem that the existing production technology using DMT as a raw material has intermittent production, resulting in large quality differences in the same batch of products and multiple batch numbers.

[0008] The utility model solves the above technical problems with the following technical solutions: A production system for continuously producing TPEE using DMT as a raw material, comprising:

[0009] A pulping system, wherein the pulping system is used to prepare pulp;

[0010] An esterification system, the esterification system being connected to the rear end of the pulping system;

[0011] A pre-shrinking kettle system, wherein the pre-shrinking kettle system is connected to the rear end of the esterification system;

[0012] The final contraction kettle system is connected to the rear end of the precontractor system. A mixer is provided at the outlet of the final contraction kettle system, and the mixer is used for adding additives.

[0013] The production system of the utility model is a continuous production system. In the process of using DMT to produce TPEE, the reaction temperature is low and the energy consumption is low during the ester exchange process. The esterification rate is high, the acidity is extremely low, and the amount of by-product tetrahydrofuran (THF) generated is also very small. Equipped with a MEOH (methanol) / THF separation system, it can ensure stable production process conditions and stable product quality.

[0014] Further: the pulping system comprises:

[0015] A slurry preparation tank, wherein the top of the slurry preparation tank is provided with a raw material injection port and an additive injection port, and the bottom of the slurry preparation tank is provided with a first slurry discharge port;

[0016] A slurry finished product tank, wherein a slurry injection port is provided on the top of the slurry finished product tank, the slurry injection port is communicated with the first slurry discharge port, and a second slurry discharge port is provided on the bottom of the slurry finished product tank.

[0017] The beneficial effects of adopting this step are as follows: the slurry is prepared according to the measurement, stirred and prepared in the slurry preparation tank, and then the prepared slurry is introduced into the slurry finished product tank for storage.

[0018] Further: the esterification system comprises an esterification reactor, the top of the esterification reactor is provided with a third slurry injection port, and the slurry injection port is connected to the second slurry discharge port;

[0019] The esterification reactor is also provided with an esterification product outlet.

[0020] The beneficial effect of adopting this step is that the slurry undergoes esterification reaction in the esterification reactor to generate PBT oligomers and the like.

[0021] Furthermore, the pre-condensation kettle system comprises a pre-condensation reactor, and the pre-condensation reactor is provided with an esterification product inlet and a prepolymer outlet, and the esterification product inlet and the esterification product outlet are connected.

[0022] The beneficial effect of adopting this step is that the esterified product enters the pre-polycondensation reaction kettle for pre-polycondensation reaction.

[0023] Further: the final polycondensation reactor system comprises a mixing tank and a final polycondensation reactor;

[0024] The mixing tank is provided with a prepolymer inlet and a mixture outlet, the prepolymer inlet is communicated with the esterification outlet, and is also connected with a polyol inlet;

[0025] The final polycondensation reactor is provided with a mixture inlet, and the mixture inlet is communicated with the mixture outlet.

[0026] The beneficial effect of adopting this step is that the prepolymer enters the final polycondensation reaction kettle for final polycondensation reaction.

[0027] Furthermore: a filter is provided between the mixing tank and the final polycondensation reactor;

[0028] The rear end of the mixer is connected to the underwater pelletizing equipment, and a filter is also arranged between the mixer and the underwater pelletizing equipment.

[0029] The beneficial effect of adopting this step is that the filter is used to filter impurities to ensure that the raw materials entering the underwater pelletizing equipment are pure and do not affect the pelletizing effect.

[0030] Furthermore: the pulping system, the esterification system, the pre-contraction kettle system and the final contraction kettle system are also connected to a BDO system;

[0031] The BDO system includes a separation circulation system and a vacuum system;

[0032] The separation circulation system comprises a separation tower and a process tower;

[0033] The bottom of the process tower is provided with a mixed gas inlet and a liquid BDO outlet, the mixed gas inlet is connected to the esterification reactor, the liquid BDO outlet is divided into two paths, one path is connected to the slurry preparation tank, and the other path is connected to the esterification reactor, and the path is also connected to a catalyst inlet, and the top of the process tower is provided with a mixed gas outlet, the mixed gas outlet is connected to the first heat exchanger, and the first heat exchanger is also provided with a first non-condensable gas outlet, a first liquid outlet and a first gas outlet, wherein the first gas outlet is connected to the process tower;

[0034] The bottom of the separation tower is provided with a mixed liquid inlet and a THF outlet, the mixed liquid inlet is connected to the first liquid outlet, the top of the separation tower is provided with a MEOH outlet, the MEOH outlet is connected to the second heat exchanger, the second heat exchanger is further provided with a second non-condensable gas outlet, a second liquid outlet and a second gas outlet, wherein the second gas outlet is connected to the separation tower;

[0035] The vacuum system comprises three vacuum jet pumps, which are connected in parallel, are respectively connected to the BDO evaporator and are respectively connected to the liquid seal tank, and the liquid seal tank then flows back to the three vacuum jet pumps respectively;

[0036] Among them, the vacuum jet pump at the front end is connected to the final polycondensation reactor, the vacuum jet pump in the middle is connected to the pre-polycondensation reactor, and the vacuum jet pump at the rear end is connected to the vacuum pump.

[0037] The beneficial effects of adopting this step are as follows: the separation circulation system separates MEOH and THF, and the vacuum system ensures that the internal spaces of the pre-polycondensation reactor and the final polycondensation reactor are in a vacuum state.

[0038] Further: a scraper condenser and a liquid seal tank are provided between the front end vacuum jet pump and the final polycondensation reactor, and between the middle vacuum jet pump and the pre-polycondensation reactor, and the scraper condenser is connected to the vacuum jet pump and the final polycondensation reactor and the vacuum jet pump and the pre-polycondensation reactor respectively;

[0039] The liquid seal tank is connected to the liquid outlet and the gas outlet of the scraper condenser.

[0040] Beneficial effects of this step: The scraper condenser and the liquid seal tank are mainly used to separate the non-condensable components in the BDO steam.

[0041] Furthermore: the bottoms of the separation tower and the process tower are both provided with heat exchangers for separating liquid working fluids.

[0042] The beneficial effects of adopting this step are: providing condensation of the working fluid, separating the liquid working fluid and the gaseous working fluid, and improving the purity of the separation product.

[0043] The beneficial effects of the utility model are:

[0044] 1. This application uses DMT as raw material and changes the original intermittent production to a continuous production system, so that the quality of the products produced is stable and the batch number is small;

[0045] 2. The present application adopts an esterification system consisting of an efficient esterification reaction tower and uses a more efficient temperature-controlled plug flow reaction technology to improve the efficiency of the esterification reaction (the esterification rate of the dibasic acid can be controlled to be no less than 99.9%), reduce the generation of by-products and the number of subsequent processing equipment, thereby reducing the number of equipment in the entire production system. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A production flow chart of a production system for continuously producing TPEE using DMT as raw material provided by the utility model;

[0048] Figure 2 This is a production flow chart of a separation circulation system in a production system for continuously producing TPEE using DMT as a raw material provided by the utility model;

[0049] Figure 3The utility model provides a production flow chart of a vacuum system in a production system for continuously producing TPEE using DMT as raw material.

[0050] Reference numerals:

[0051] 1-slurry preparation tank; 2-slurry finished product tank; 3-esterification reactor; 4-pre-polycondensation reactor; 5-mixing tank; 6-final polycondensation reactor; 7-underwater pelletizing equipment; 8-mixer; 9-separation circulation system; 10-vacuum system;

[0052] 91-process tower; 92-separation tower; 93-first heat exchanger; 94-second heat exchanger; 95-non-condensable gas outlet; 96-MEOH outlet; 97-THF outlet; 98-heat exchanger; 99-pump;

[0053] 101-BDO steam inlet; 102-vacuum pump; 103-vacuum jet pump; 104-scraper condenser; 105-liquid seal tank. DETAILED DESCRIPTION

[0054] The following embodiments of the technical solution of the utility model are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and are therefore only used as examples, and cannot be used to limit the protection scope of the utility model.

[0055] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by technicians in the field to which the utility model belongs.

[0056] Example

[0057] like Figure 1 , Figure 2 and Figure 3 As shown, the utility model provides a production system for continuously producing TPEE using DMT as a raw material, comprising:

[0058] A pulping system, wherein the pulping system is used to prepare pulp;

[0059] An esterification system, the esterification system being connected to the rear end of the pulping system;

[0060] A pre-shrinking kettle system, wherein the pre-shrinking kettle system is connected to the rear end of the esterification system;

[0061] The final contraction kettle system is connected to the rear end of the precontractor system. A mixer 8 is provided at the outlet of the final contraction kettle system. The mixer 8 is used for adding additives.

[0062] The production system of the utility model is a continuous production system. In the process of using DMT to produce TPEE, the reaction temperature is low and the energy consumption is low during the ester exchange process. The esterification rate is high, the acidity is extremely low, and the amount of by-product tetrahydrofuran (THF) generated is also very small. Equipped with a MEOH (methanol) / THF separation system, it can ensure stable production process conditions and stable product quality.

[0063] On the basis of the above technical solution, the pulping system comprises:

[0064] A slurry preparation tank 1, wherein the top of the slurry preparation tank 1 is provided with a raw material injection port and an additive injection port, and the bottom of the slurry preparation tank 1 is provided with a first slurry discharge port;

[0065] A slurry finished product tank 2 is provided with a slurry injection port on the top thereof, the slurry injection port is communicated with the first slurry discharge port, and a second slurry discharge port is provided at the bottom thereof.

[0066] The slurry is prepared according to the measurement, stirred and prepared in the slurry preparation tank, and then the prepared slurry is introduced into the slurry finished product tank for storage.

[0067] On the basis of the above technical solution, the esterification system comprises an esterification reactor 3, the top of the esterification reactor 3 is provided with a third slurry injection port, and the slurry injection port is connected to the second slurry discharge port;

[0068] The esterification reactor 3 is also provided with an esterification product outlet.

[0069] The beneficial effect of adopting this step is that the slurry undergoes esterification reaction in the esterification reactor 3 to generate PBT oligomers and the like.

[0070] On the basis of the above technical solution, the precondensation kettle system comprises a precondensation reactor 4, and the precondensation reactor 4 is provided with an esterification product inlet and a prepolymer outlet, and the esterification product inlet and the esterification product outlet are connected.

[0071] The beneficial effect of adopting this step is that the esterified product enters the pre-polycondensation reaction kettle 4 for pre-polycondensation reaction.

[0072] On the basis of the above technical solution, the final polycondensation reactor system comprises a mixing tank 5 and a final polycondensation reactor 6;

[0073] The mixing tank 5 is provided with a prepolymer inlet and a mixture outlet, the prepolymer inlet is connected to the esterification outlet, and is also connected to a polyol inlet;

[0074] The final polycondensation reactor 6 is provided with a mixture inlet, and the mixture inlet is communicated with the mixture outlet.

[0075] The beneficial effect of adopting this step is that the prepolymer enters the final polycondensation reaction kettle 6 for final polycondensation reaction.

[0076] On the basis of the above technical solution, a filter is further provided between the mixing tank 5 and the final polycondensation reactor 6;

[0077] The rear end of the mixer 8 is connected to the underwater pelletizing equipment 7 , and a filter is also provided between the mixer 8 and the underwater pelletizing equipment 7 .

[0078] The filter is used to filter impurities to ensure that the raw materials entering the underwater pelletizing equipment are pure and do not affect the pelletizing effect.

[0079] On the basis of the above technical solution, the pulping system, the esterification system, the pre-contraction kettle system and the final contraction kettle system are also connected to the BDO system;

[0080] The BDO system includes a separation circulation system 9 and a vacuum system 10;

[0081] The separation circulation system 9 includes a separation tower 92 and a process tower 91;

[0082] The bottom of the process tower 91 is provided with a mixed gas inlet and a liquid BDO outlet, the mixed gas inlet is connected to the esterification reactor 3, the liquid BDO outlet is divided into two paths, one path is connected to the slurry preparation tank 1, and the other path is connected to the esterification reactor 3, and the path is also connected to a catalyst inlet, and the top of the process tower 91 is provided with a mixed gas outlet, the mixed gas outlet is connected to the first heat exchanger 93, and the first heat exchanger 93 is also provided with a first non-condensable gas outlet, a first liquid outlet and a first gas outlet, wherein the first gas outlet is connected to the process tower;

[0083] The bottom of the separation tower 92 is provided with a mixed liquid inlet and a THF outlet 97, the mixed liquid inlet is connected to the first liquid outlet, the top of the separation tower is provided with a MEOH outlet, the MEOH outlet is connected to the second heat exchanger 94, the second heat exchanger 94 is further provided with a second non-condensable gas outlet, a second liquid outlet and a second gas outlet, wherein the second gas outlet is connected to the separation tower, and the second liquid outlet is a MEOH outlet 96;

[0084] The first non-condensable gas outlet and the second non-condensable gas outlet converge into a non-condensable gas outlet 95;

[0085] The vacuum system 10 includes three vacuum jet pumps 103, which are connected in parallel. The three vacuum jet pumps 103 are respectively connected to the BDO evaporator and the liquid seal tank 105, and the liquid seal tank 105 is then refluxed to the three vacuum jet pumps 103;

[0086] The front end of the vacuum jet pump 103 is connected to the final polycondensation reactor 6 , the middle vacuum jet pump 103 is connected to the pre-polycondensation reactor 4 , and the rear end of the vacuum jet pump 103 is connected to the vacuum pump 102 .

[0087] The separation circulation system 9 separates MEOH and THF, and the vacuum system 10 ensures that the internal spaces of the pre-polycondensation reactor 4 and the final polycondensation reactor 6 are in a vacuum state.

[0088] On the basis of the above technical solution, a scraper condenser 104 and a liquid seal tank 105 are provided between the front end of the vacuum jet pump 103 and the final polycondensation reactor 6, and between the middle vacuum jet pump 103 and the pre-polycondensation reactor 4. The scraper condenser 104 is connected to the vacuum jet pump 103 and the final polycondensation reactor 6 and the vacuum jet pump 103 and the pre-polycondensation reactor 4 respectively.

[0089] The liquid seal tank 105 is connected to the liquid outlet and the gas outlet of the scraper condenser 104 .

[0090] The scraper condenser 104 and the liquid seal tank 105 are mainly used to separate the non-condensable components in the BDO steam.

[0091] On the basis of the above technical solution, the bottoms of the separation tower 92 and the process tower 91 are both provided with heat exchangers 98 for separating liquid working fluids.

[0092] The beneficial effects of adopting this step are: providing condensation of the working fluid, separating the liquid working fluid and the gaseous working fluid, and improving the purity of the separation product.

[0093] It should be noted that the pump body used for pumping slurry, prepolymer, final polymer and other auxiliary materials in the production system belongs to the technical application well known in the art, so it is not described in detail.

[0094] Finally, the working status of this production system is explained in detail.

[0095] (1) The pulping system process is as follows: the raw material BDO is added to the slurry preparation tank 1 according to a certain metering, and then the DMT powder, flakes or blocks with a certain molar ratio are added to the slurry preparation tank 1 according to a certain number of packages. Stirring and mixing at a certain heating temperature; adding a certain amount of weighed additives. After the slurry is prepared, it is pumped to the slurry finished product tank 2 for continuous feeding. The slurry in the slurry finished product tank 2 is quantitatively and continuously pumped to the esterification reactor 3 according to a certain metering through a pump.

[0096] (2) The esterification reaction process is as follows: the slurry enters from the upper part of the esterification reactor 3, and at a certain temperature and pressure, DMT and BDO undergo esterification reaction to generate PBT oligomers and methanol. BDO undergoes cyclization at high temperature to generate THF (tetrahydrofuran) and water. Under stirring, by controlling the residence time, reaction pressure and reaction temperature, the esterification rate of the dibasic acid is controlled to be not less than 99.9%. The esterified product is quantitatively delivered to the prepolymerization reactor 4 via a delivery pump.

[0097] (3) The vapor phase BDO, MEOH and THF in the esterification reactor enter the process tower 91 for distillation. A portion of the liquid BDO in the kettle of the process tower 91 is mixed with a catalyst in a certain amount and then refluxed from the bottom of the esterification kettle to the esterification reactor 3, and a portion of the BDO is used for slurry preparation. The top of the process tower 91 is cooled by the first heat exchanger 93, and the liquid MEOH and THF are pumped to the separation tower 92 to separate MEOH and THF and collect them separately.

[0098] (4) The prepolymerization system process is that the material from the esterification reactor 3 undergoes polycondensation reaction in the pre-polycondensation reactor 4. Under stirring, a certain residence time, temperature and vacuum environment, small molecules such as BDO generated by the reaction are continuously released, and the degree of polymerization gradually increases. The evaporated small molecules enter the scraper condenser 104 through the gas phase pipeline under the suction action of the vacuum pump 102. The prepolymer is finally discharged from the outlet at the bottom of the reactor and is pumped to the final polycondensation reactor 6 by the prepolymer pump.

[0099] (5) The prepolymer from the pre-polycondensation reactor 4 is quantitatively pumped into the mixing tank 5 with a certain proportion of polyol for continuous mixing, and then pumped to the filter and the final polycondensation reactor 6. The final polycondensation reactor 6 is a parallel double-axis structure. The material forms a film on the internal disk for devolatilization, and small molecular BDO and water are continuously released under high vacuum conditions, and further polycondensation reaction occurs. The BDO vapor released by the reaction is extracted by the vacuum system 10 through the gas phase pipeline and sprayed to capture, and the non-condensable tail gas is extracted by the vacuum pump 102 group and sent to tail gas treatment.

[0100] (6) The special structure inside the final polycondensation reactor 6 provides sufficient conditions for the axial flow and radial film-forming devolatilization of the high-viscosity melt, improves the BDO release rate in the liquid phase, achieves the purpose of rapid release of BDO, and enables the polycondensation reaction to proceed smoothly under high viscosity conditions. The final polycondensation reaction is carried out under vacuum, and the vacuum degree of the final polycondensation is adjusted by automatically adjusting the opening of the BDO dilution steam regulating valve of the injection pump to control the reaction rate. The melt discharge viscosity of the final polycondensation reactor can reach a melt index of 5-30g / 10min. After the melt passes through the mixer 8 and the additives are added, it is directly sent to the underwater pelletizing equipment 7 for pelletization through the filter.

[0101] (7) Each reactor is heated by a secondary heat medium circulation system.

[0102] (8) The vacuum system 10 is mainly composed of a vacuum jet pump 103. The vacuum of the pre-polycondensation reactor 4 and the final polycondensation reactor 6 is provided by the vacuum jet pump 103. BDO steam is generated from a steam generator, enters from a BDO steam inlet, and is sent to the nozzle of the vacuum jet pump 103. The circulating cooling BDO is used as a cold medium for spraying, and can condense and absorb the condensable components in the process tail gas ejected from the nozzle, the pre-polycondensation scraper condenser 104, and the final polycondensation scraper condenser 104. The condensed BDO flows into the BDO liquid seal tank 105 by gravity, and then is extracted by a circulating pump 99, cooled by a circulating cooler, and then sent back to the spraying. The non-condensable components in the process tail gas are extracted and discharged by the vacuum pump 102.

[0103] In the above process, the slurry temperature is controlled at 50-150°C, and the slurry is transported to the esterification reactor 3 by a slurry delivery pump for esterification reaction. The reaction temperature is controlled at 190-220°C, the reaction pressure is controlled at 30-100 kPa.a, and the residence time is controlled at 80-240 minutes. The esterified product is transported to the polycondensation system by an esterification product delivery pump. MEOH, THF and BDO generated by the esterification reaction are separated by a process tower 91 and a separation tower 92.

[0104] The reaction residence time of the pre-polycondensation reactor 4 is controlled between 40 and 120 minutes, the reaction temperature is controlled between 230 and 260° C., and the reaction pressure is controlled between 800 and 1500 Pa.a.

[0105] The final polycondensation reactor 6 has a reaction residence time controlled between 80 and 190 minutes, a reaction temperature controlled between 230 and 260° C., and a reaction pressure controlled between 30 and 300 Pa.a. The melt after the reaction is completed is sent to the underwater pelletizing equipment 7 for pelletizing.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. A production system for continuously producing TPEE using DMT as raw material, characterized in that: include: A pulping system, wherein the pulping system is used to prepare pulp; An esterification system, the esterification system being connected to the rear end of the pulping system; A pre-shrinking kettle system, wherein the pre-shrinking kettle system is connected to the rear end of the esterification system; The final contraction kettle system is connected to the rear end of the precontractor system. A mixer is provided at the outlet of the final contraction kettle system, and the mixer is used for adding additives.

2. The production system for continuously producing TPEE using DMT as raw material according to claim 1, characterized in that: The pulping system comprises: A slurry preparation tank, wherein the top of the slurry preparation tank is provided with a raw material injection port and an additive injection port, and the bottom of the slurry preparation tank is provided with a first slurry discharge port; A slurry finished product tank, wherein a slurry injection port is provided on the top of the slurry finished product tank, the slurry injection port is communicated with the first slurry discharge port, and a second slurry discharge port is provided on the bottom of the slurry finished product tank.

3. The production system for continuously producing TPEE using DMT as raw material according to claim 2, characterized in that: The esterification system comprises an esterification reactor, the top of which is provided with a third slurry injection port, the slurry injection port being connected to the second slurry discharge port; The esterification reactor is also provided with an esterification product outlet.

4. The production system for continuously producing TPEE using DMT as raw material according to claim 3, characterized in that: The precondensation kettle system comprises a precondensation reactor, and the precondensation reactor is provided with an esterification product inlet and a prepolymer outlet, and the esterification product inlet and the esterification product outlet are communicated.

5. The production system for continuously producing TPEE using DMT as raw material according to claim 4, characterized in that: The final polycondensation reactor system comprises a mixing tank and a final polycondensation reactor; The mixing tank is provided with a prepolymer inlet and a mixture outlet, the prepolymer inlet is communicated with the esterification outlet, and is also connected with a polyol inlet; The final polycondensation reactor is provided with a mixture inlet, and the mixture inlet is communicated with the mixture outlet.

6. The production system for continuously producing TPEE using DMT as raw material according to claim 5, characterized in that: A filter is also provided between the mixing tank and the final polycondensation reactor; The rear end of the mixer is connected to the underwater pelletizing equipment, and a filter is also arranged between the mixer and the underwater pelletizing equipment.

7. The production system for continuously producing TPEE using DMT as raw material according to claim 6, characterized in that: The pulping system, the esterification system, the pre-contraction kettle system and the final contraction kettle system are also connected to a BDO system; The BDO system includes a separation circulation system and a vacuum system; The separation circulation system comprises a separation tower and a process tower; The bottom of the process tower is provided with a mixed gas inlet and a liquid BDO outlet, the mixed gas inlet is connected to the esterification reactor, the liquid BDO outlet is divided into two paths, one path is connected to the slurry preparation tank, and the other path is connected to the esterification reactor, and the path is also connected to a catalyst inlet, and the top of the process tower is provided with a mixed gas outlet, the mixed gas outlet is connected to the first heat exchanger, and the first heat exchanger is also provided with a first non-condensable gas outlet, a first liquid outlet and a first gas outlet, wherein the first gas outlet is connected to the process tower; The bottom of the separation tower is provided with a mixed liquid inlet and a THF outlet, the mixed liquid inlet is connected to the first liquid outlet, the top of the separation tower is provided with a MEOH outlet, the MEOH outlet is connected to the second heat exchanger, the second heat exchanger is further provided with a second non-condensable gas outlet, a second liquid outlet and a second gas outlet, wherein the second gas outlet is connected to the separation tower; The vacuum system comprises three vacuum jet pumps, which are connected in parallel, are respectively connected to the BDO evaporator and are respectively connected to the liquid seal tank, and the liquid seal tank then flows back to the three vacuum jet pumps respectively; Among them, the vacuum jet pump at the front end is connected to the final polycondensation reactor, the vacuum jet pump in the middle is connected to the pre-polycondensation reactor, and the vacuum jet pump at the rear end is connected to the vacuum pump.

8. The production system for continuously producing TPEE using DMT as raw material according to claim 7, characterized in that: A scraper condenser and a liquid seal tank are provided between the front end vacuum jet pump and the final polycondensation reactor, and between the middle vacuum jet pump and the pre-polycondensation reactor. The scraper condenser is connected to the vacuum jet pump and the final polycondensation reactor, and the vacuum jet pump and the pre-polycondensation reactor respectively. The liquid seal tank is connected to the liquid outlet and the gas outlet of the scraper condenser.

9. The production system for continuously producing TPEE using DMT as raw material according to claim 8, characterized in that: The bottoms of the separation tower and the process tower are both provided with heat exchangers for separating liquid working media.

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