Integrated system for efficient recovery of ethylene glycol

Abstract

The application discloses a kind of efficient recovery integrated system of ethylene glycol, it is related to ethylene glycol distillation recovery technical field.In the present application, primary condenser and secondary condenser are all included at least two condensing flow channels, condensing flow channel outside is surrounded with gas phase flow channel, the outer wall of condensing flow channel is coated with nano hydrophobic coating for improving heat transfer coefficient;Condensing flow channel is equipped with the small ball of turbulence that moves with liquid flow, and the small ball of turbulence is used to thin the thermal resistance boundary layer of condensing flow channel inner wall;The collision frequency of small ball of turbulence and condensing flow channel inner wall is increased by ultrasonic for cooling liquid flowing in condensing flow channel, to improve the flow velocity of condensing liquid attached to condensing flow channel inner wall.The present application is designed by nano hydrophobic coating+ultrasonic+small ball of turbulence, which ensures that the outer wall of condensing flow channel will not reduce the heat transfer coefficient due to the existence of static condensing liquid film, so as to improve the condensing effect of each condensing flow channel.

Description

Technical Field

[0001] This invention belongs to the field of ethylene glycol distillation and recovery technology, and in particular relates to an integrated system for high-efficiency ethylene glycol recovery. Background Technology

[0002] Ethylene glycol is a core raw material in the chemical industry, widely used in polyester, antifreeze, fine chemicals, and many other fields. The stable and efficient operation of ethylene glycol purification and concentration units is crucial for ensuring product quality and production efficiency. In existing industrial ethylene glycol concentration processes, the light components collected from the top reflux tank of the ethylene glycol dehydrator, along with a small amount of demineralized water, are typically fed into the middle of the ethylene glycol concentration tower. Purification and separation are achieved using a thermosiphon reboiler at the bottom and a cooling structure at the top of the tower. High-purity ethylene glycol is pumped to the liquid-phase hydrogenation process or the dehydrator via a bottom pump. The condensate is collected in a reflux tank; a portion is returned to the top of the tower to maintain distillation balance, while the other portion is collected, cooled, and used as a mixed alcohol-ester byproduct. Uncondensed and non-condensable gases are treated using a vacuum system. This process is currently the mainstream ethylene glycol concentration and purification solution in the industry, characterized by its maturity and strong adaptability.

[0003] However, during long-term continuous industrial operation, the existing condensation heat exchange system of the ethylene glycol concentration tower has significant technical defects, restricting the operating efficiency and production economy of the unit. Firstly, traditional condensation heat exchange equipment relies solely on static fluid heat exchange, making it prone to scale buildup on the inner wall of the condenser tubes. Simultaneously, a stable thermal resistance boundary layer easily forms, reducing the heat transfer coefficient of the tube wall and causing a continuous decline in the heat exchange efficiency of the cooler. The condensation effect of the gas phase at the top of the tower is unstable, easily leading to insufficient condensation and incomplete separation of light components, directly affecting the purity of the ethylene glycol product and the recovery rate of by-products. Secondly, existing equipment lacks an online self-cleaning function. Scale buildup on the tube walls increases fluid flow resistance, causing the circulating pump to operate at high load for extended periods, resulting in continuously increasing energy consumption. Thirdly, traditional descaling maintenance methods require shutdown for chemical acid washing or high-pressure water jet cleaning. This not only interrupts the continuous production process and reduces the unit's operating capacity, but chemical cleaning also easily causes equipment corrosion and media residues, posing environmental and production safety hazards and failing to meet the long-cycle, high-efficiency, and low-energy-consumption industrial production requirements of ethylene glycol units.

[0004] Therefore, there is an urgent need to develop a composite, high-efficiency anti-scaling and enhanced heat exchange structure adapted to the operating conditions of ethylene glycol concentration towers. This structure should integrate the advantages of multiple technologies, including ultrasonic vibration, fluid turbulence, mechanical scraping, and nano-hydrophobic modification, to solve the technical problems of heat exchange efficiency degradation, easy scaling, and cumbersome maintenance in existing equipment. This would enable long-term stable operation of the condensation heat exchange system, online real-time descaling, and extended equipment lifespan, ensuring efficient, continuous, and low-cost production of ethylene glycol concentration and purification processes. Summary of the Invention

[0005] The purpose of this invention is to provide an integrated system for the efficient recovery of ethylene glycol. Through the specific structural design of the reflux device, primary condenser, secondary condenser, ultrasonic emission channel, ultrasonic generator, ball limiting assembly, lower filter plate, upper filter plate, storage cylinder and suspension component, the problems in the background art mentioned above are solved.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: The present invention is an integrated system for high-efficiency recovery of ethylene glycol, including an ethylene glycol concentration tower. The bottom of the ethylene glycol concentration tower is equipped with a thermosiphon reboiler, and a reflux device is provided on one side of the top of the ethylene glycol concentration tower. A primary condenser and a secondary condenser are respectively provided above the reflux device. The reflux device is used to receive the condensate from each condenser and partially return it to the ethylene glycol concentration tower. The condensation temperature of the primary condenser is controlled at 55.3℃, and the condensation temperature of the secondary condenser is controlled at -10℃. The primary condenser is used to receive and condense the top gas phase of the ethylene glycol concentration tower.

[0007] Both the primary and secondary condensers include at least two condensation channels. A gas phase channel is provided around the outside of the condensation channels, and the outer wall of the condensation channels is coated with a nano-hydrophobic coating to improve the heat transfer coefficient. The condensation channels are provided with turbulence-inducing balls that move with the liquid flow and slightly vibrate their tube walls. The coolant flowing in the condensation channels is subjected to ultrasound to increase the collision frequency between the turbulence-inducing balls and the inner surface of the condensation channels, thereby increasing the flow rate of the condensate adhering to the outer wall of the condensation channels.

[0008] The present invention is further configured such that both the primary condenser and the secondary condenser include a condenser cylinder, the condenser cylinder is arranged vertically and its circumferential side is connected to a gas phase inlet pipe, the gas phase inlet pipe is set close to the bottom of the condenser cylinder, and the gas phase inlet pipe of the primary condenser is connected to the top of the ethylene glycol concentration tower through a gas phase pipe.

[0009] The present invention is further configured such that the reflux device includes a horizontally arranged reflux cylinder, two condensate collection pipes are connected to the top of the reflux cylinder, a reflux pipe is connected to the bottom of the reflux cylinder, the reflux pipe is connected to the top of the ethylene glycol concentration tower, a branch pipe for connecting a light component cooler is connected to the bottom of the reflux cylinder, a flow regulating valve is fixedly installed on the branch pipe, and a collection hood connected to the condensate collection pipe is installed at the bottom of the condensate cylinder.

[0010] The present invention is further configured such that a support plate is fixed on the inner wall of the condenser cylinder near the bottom, a hollow lower guide section is installed on the top of the support plate, an upper guide section with a hollow structure is provided inside the condenser cylinder near the top, and a condenser inlet pipe and a condenser outlet pipe are respectively installed on the circumferential side of the condenser cylinder. The condenser inlet pipe is connected to the lower guide section, and the condenser outlet pipe is connected to the upper guide section.

[0011] The present invention is further configured such that an ultrasonic emission channel corresponding to the lower guide section and the upper guide section is fixedly installed on the inner wall of the condenser cylinder, the lower guide section and the upper guide section are respectively connected to the corresponding ultrasonic emission channel, an ultrasonic generator corresponding to the ultrasonic emission channel is installed on the circumferential side of the condenser cylinder, and an annular groove coaxial with the upper guide section is provided at the top of the upper guide section.

[0012] The present invention is further configured such that the condensation channel is connected between the lower guide section and the upper guide section, the top of the upper guide section is provided with an installation port communicating with its inner cavity, the installation port is provided one-to-one with the condensation channel, and the installation port is coaxial with the corresponding condensation channel, the diameter of the installation port is the same as the inner diameter of the condensation channel, and the gas phase channel is provided between the condensation channel, the lower guide section, the upper guide section and the condensation cylinder.

[0013] The present invention is further configured such that a small ball limiting assembly is provided inside the condenser cylinder, the small ball limiting assembly includes a flow collector hood two installed on the top of the condenser cylinder, the gas phase inlet pipe of the secondary condenser is connected to the flow collector hood two of the primary condenser through a gas phase pipe two, and the flow collector hood two of the secondary condenser is connected to the vacuum system of the ethylene glycol concentration tower through a gas phase pipe three.

[0014] The present invention is further configured such that a support disk II is fixedly installed at the bottom of the flow collector II, and both the support disk I and the support disk II are provided with a plurality of flow holes arranged in a circumferential array. A sealing ring that cooperates with the annular groove is fixed at the bottom of the support disk II. The flow holes on the support disk I are located on the outer side of the lower flow guide, and the flow holes on the support disk II are located on the outer side of the sealing ring. A plurality of sealing plugs located on the inner side of the sealing ring are fixed at the bottom of the support disk II, and the sealing plugs are tightly fitted with the corresponding mounting ports.

[0015] The invention is further configured such that a support rod is fixed at the bottom of the sealing plug within the condensation channel, and a lower filter plate and an upper filter plate are fixed on the support rod respectively. The diameters of the lower filter plate and the upper filter plate are the same as the inner diameter of the condensation channel. A turbulence ball is located between the lower filter plate and the upper filter plate. The turbulence ball is made of wear-resistant and elastic polymer material, and its density is the same as that of the coolant.

[0016] The invention is further configured such that a storage cylinder is fixed to the top of the lower filter plate of the first-stage condenser, and a suspension component is provided at the top of the storage cylinder. The suspension component consists of a cleaning ring and a limiting ring that are fixedly connected. The outer diameter of the cleaning ring is the same as the inner diameter of the condenser flow channel, and the outer diameter of the limiting ring is the same as the inner diameter of the storage cylinder. The cleaning ring is provided with a cleaning surface, an upper inclined surface, and a lower inclined surface, respectively. The upper inclined surface and the lower inclined surface are used for the rebound motion of the turbulent turbulent spheres.

[0017] The present invention has the following beneficial effects: 1. The present invention coats the outer wall of the condensation channel with a nano-hydrophobic coating and places turbulence-inducing balls within the condensation channel, which are confined between the upper and lower filter plates. The coolant flowing in the condensation channel is subjected to ultrasound to increase the collision frequency between the turbulence-inducing balls and the inner surface of the condensation channel, thereby increasing the flow rate of the condensate adhering to the outer wall of the condensation channel. This ensures that the heat transfer coefficient of each condensation channel will not be reduced due to the presence of a static condensate film, thus improving the condensation effect of each condensation channel.

[0018] 2. In this invention, ultrasonic energy can be transferred to cooling water or refrigerant, causing micro-vibrations in the cooling water or refrigerant circulating through each condensation channel. This effectively prevents the formation of scale on the inner wall of the condensation channel. At the same time, the scale loosened by ultrasonic waves can be carried away by the cooling water in time. The "ultrasonic + small ball" design realizes online real-time descaling, which can effectively reduce the formation of scale on the inner wall of the condensation channel and ensure the heat exchange and condensation effect of each condensation channel.

[0019] 3. In the continuous circulation of cooling water, the suspended parts in each condensation channel of the first-stage condenser are in a state of suspension motion. The scale removal surface on the suspended parts can dynamically clean the pipe wall of the condensation channel. The turbulent small balls will collide with the upper or lower inclined surface, thereby increasing the movement amplitude of the turbulent small balls and the suspended parts, which can further improve the condensation effect of each condensation channel. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of an integrated system for efficient ethylene glycol recovery according to the present invention.

[0022] Figure 2 for Figure 1 A structural side view.

[0023] Figure 3 for Figure 1 The front view of the structure.

[0024] Figure 4 This is a schematic diagram of the structure of the primary or secondary condenser in this invention.

[0025] Figure 5 for Figure 4 The front view of the structure.

[0026] Figure 6This is a diagram showing the internal structure of the first-stage condenser in this invention.

[0027] Figure 7 This is a cross-sectional view of the condenser cylinder in this invention.

[0028] Figure 8 This is a schematic diagram of the structure of the ball limiting assembly on the first-stage condenser in this invention.

[0029] Figure 9 for Figure 8 A structural diagram viewed from below.

[0030] Figure 10 This is a schematic diagram of the suspension component in this invention.

[0031] The attached diagram lists the components represented by each number as follows:

[0032] 1. Ethylene glycol concentration tower; 2. Thermosiphon reboiler; 3. Reflux device; 4. Primary condenser; 5. Secondary condenser; 6. Condensation channel; 7. Condensation cylinder; 8. Gas phase inlet pipe; 9. Gas phase pipe one; 10. Reflux cylinder; 11. Reflux pipeline; 12. Diverter pipeline; 13. Flow regulating valve; 14. Flow collector one; 15. Support plate one; 16. Lower guide section; 17. Upper guide section; 18. Condensation inlet pipe; 19. Condensation outlet pipe; 20. 21. Ultrasonic emission channel; 22. Ultrasonic generator; 23. Annular groove; 24. Mounting port; 25. Small ball limiting assembly; 26. Second flow collector; 27. Second gas phase pipe; 28. Second support plate; 29. ​​Flow passage; 30. Sealing ring; 31. Sealing plug; 32. Support rod; 33. Lower filter plate; 34. Upper filter plate; 35. Storage cylinder; 36. Suspension component; 37. Scaling ring; 38. Limiting ring; 39. Scaling surface; 40. Upper inclined surface; 51. Lower inclined surface. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Example 1, please refer to Figures 1 to 10 This invention relates to an integrated system for efficient ethylene glycol recovery, comprising an ethylene glycol concentration tower 1, a thermosiphon reboiler 2 at the bottom of the tower, and a reflux device 3 on one side of the top of the tower. Above the reflux device 3 are a primary condenser 4 and a secondary condenser 5, with the secondary condenser 5 located at the rear end of the primary condenser 4. The reflux device 3 is used to receive the condensate from each condenser and partially return it to the ethylene glycol concentration tower 1.

[0035] The condensing temperature of the primary condenser 4 is controlled at 55.3℃, and the condensing temperature of the secondary condenser 5 is controlled at -10℃. The primary condenser 4 is used to receive and condense the overhead vapor phase of the ethylene glycol concentration tower 1. Specifically, the bottom of the ethylene glycol concentration tower 1 is heated with 1.7 MPaG saturated steam, and the bottom temperature is controlled at 148℃ to obtain high-purity ethylene glycol product with a concentration ≥99%. The overhead vapor phase is sequentially condensed by primary condensation with circulating water at 55.3℃ and secondary condensation with cryogenic liquid at -10℃. The condensate collected by the reflux device 3 mainly consists of light components, including demineralized water, light alcohols, and esters. The data collected during the operation of the ethylene glycol concentration tower 1 are shown in the table below:

[0036] Table 1. Data collected during the operation of the ethylene glycol concentration tower.

[0037] 2025.04.15-13:00 2.826 3546.673 4.707 129.22 148.53 1.515 1.667 2025.04.15-14:00 2.835 3467.388 4.707 128.88 148.17 1210 1.513 2025.04.15-15:00 2.815 3587.539 4.806 129.18 148.695 1.538 1.292 2025.04.15-16:00 2.827 3560.387 4.88 129.32 148.47 1.444 1.330 2025.04.15-17:00 2.819 3627.348 4.841 129.38 148.695 1.485 1.396 2025.04.15-18:00 2.81 3607.857 4.816 128.87 148.56 1.081 1.403 2025.04.15-19:00 2.813 3566.817 4.904 129.04 148.47 1.352 1.586 2025.04.15-20:00 2.821 3558.963 4.805 129.12 148.5 1.354 1.500 2025.04.15-21:00 2.799 3587.56 4.704 129.17 148.455 1.357 1.493 2025.04.15-22:00 2.806 3552.347 4.816 129.28 148.44 1.356 1.497 2025.04.15-23:00 2.807 3589.951 4.836 129.11 148.56 1.357 1.441 2025.04.16-00:00 2.809 3572.156 4.846 129.05 148.56 1.353 1.42 2025.04.16-01:00 2.801 3660.598 4.812 129.17 148.665 1.361 1.422 2025.04.16-02:00 2.806 3539.845 4.946 128.89 148.41 1.363 1.434 2025.04.16-03:00 2.803 3624.35 4.89 128.97 148.56 1.358 1.421

[0038] The light components and a small amount of demineralized water collected from the top reflux tank of the ethylene glycol dehydrator are fed into the middle of ethylene glycol concentration tower 1. The collected light components and a small amount of demineralized water serve as the concentrate feed. The concentrate feed gradually flows downward along the trays inside ethylene glycol concentration tower 1. The downward-flowing concentrate feed comes into contact with the rising steam generated in the bottom of the tower. The steam continuously "evaporates" the residual light components in the liquid concentrate feed and carries them to the top of the tower, making the ethylene glycol concentration in the liquid flowing to the bottom of the tower increasingly higher. Meanwhile, the condensate returning from the top of the tower to ethylene glycol concentration tower 1 comes into contact with the rising gas phase, allowing the light components to continuously concentrate upward and finally be collected from the top of the tower. This process achieves the concentrated production of ethylene glycol.

[0039] Both the primary condenser 4 and the secondary condenser 5 include at least two condensation channels 6. The inner cavity of the condensation channel 6 is used for the continuous flow of cooling water or refrigerant from bottom to top. The outer side of the condensation channel 6 is surrounded by a gas phase flow channel, which ensures that the gas phase entering the gas phase flow channel from the bottom can fully contact the outer wall of each condensation channel 6 to achieve condensation. The outer wall of the condensation channel 6 is coated with a nano-hydrophobic coating to improve the heat transfer coefficient, that is, a nano-hydrophobic coating is uniformly coated on the outer wall of each condensation channel 6.

[0040] The condensation channel 6 is equipped with small turbulence balls that move with the liquid flow and slightly vibrate its wall. The cooling water or refrigerant flowing in the condensation channel 6 can increase the collision frequency between the turbulence balls and the inner wall of the condensation channel 6 through ultrasonic action. The ultrasonic power density can be controlled between 0.5-1.5 W / cm³. 2 This increases the flow rate of the condensate adhering to the outer wall of the condensation channel 6, ensuring that the heat transfer coefficient of each condensation channel 6 is not reduced due to the presence of a static condensate film, thus improving the condensation effect of each condensation channel 6.

[0041] In this embodiment of the invention, as Figure 4 and Figure 7 As shown, both the primary condenser 4 and the secondary condenser 5 include a condenser body 7. The condenser body 7 is arranged vertically and its circumferential side is connected to a gas phase inlet pipe 8. The gas phase inlet pipe 8 is set close to the bottom of the condenser body 7. The gas phase inlet pipe 8 of the primary condenser 4 is connected to the top of the ethylene glycol concentration tower 1 through a gas phase pipe 9. The setting of the gas phase pipe 9 can ensure that the gas phase at the top of the ethylene glycol concentration tower 1 enters the gas phase flow channel inside the condenser body 7 along the gas phase pipe 9 and the gas phase inlet pipe 8.

[0042] In this embodiment of the invention, as Figures 1 to 3 As shown, the reflux device 3 includes a horizontally arranged reflux cylinder 10. The top of the reflux cylinder 10 is connected to two condensate collection pipes, and the bottom of the reflux cylinder 10 is connected to a reflux pipe 11. The reflux pipe 11 is connected to the top of the ethylene glycol concentration tower 1. It should be noted that the shape of the reflux pipe 11 can be adapted to meet the actual production process requirements. At the same time, a check valve can be installed on the reflux pipe 11 or not, depending on the actual production process requirements.

[0043] The bottom of the reflux cylinder 10 is connected to a diversion pipe 12 for connecting to the light component cooler. Through the position design of the entire reflux device 3, it can be ensured that part of the condensate in the reflux cylinder 10 flows by gravity along the reflux pipe 11 to the ethylene glycol concentration tower 1, while part of the condensate flows by gravity along the diversion pipe 12 to the light component cooler. The mixed alcohol ester obtained in the light component cooler is transported to the storage tank for storage. A flow regulating valve 13 is fixedly installed on the diversion pipe 12. The flow regulating valve 13 can be used to adjust the condensate flow rate of the diversion pipe 12, and thus the condensate reflux ratio can be adjusted according to process requirements. The bottom of the condenser cylinder 7 is equipped with a flow collecting hood 14 connected to the condensate collection pipe. The condensate in the condenser cylinder 7 is collected at the flow collecting hood 14 and enters the reflux cylinder 10 along the condensate collection pipe.

[0044] In this embodiment of the invention, as Figure 7 As shown, a support plate 15 is fixed to the inner wall of the condenser cylinder 7 near the bottom. A hollow lower guide section 16 is installed on the top of the support plate 15. A hollow upper guide section 17 is provided inside the condenser cylinder 7 near the top. A condenser inlet pipe 18 and a condenser outlet pipe 19 are respectively installed on the circumferential sides of the condenser cylinder 7. The condenser inlet pipe 18 is connected to the lower guide section 16, and the condenser outlet pipe 19 is connected to the upper guide section 17. It should be noted that the primary condenser 4 and the secondary condenser 5 are respectively equipped with a circulating condensation system installed on the external frame. Each circulating condensation system is connected to the corresponding condenser inlet pipe 18 and condenser outlet pipe 19 to realize the circulation of cooling water or refrigerant between the condenser inlet pipe 18 and the condenser outlet pipe 19. The circulating condensation system is a conventional device in the prior art, so it will not be described in detail here.

[0045] In this embodiment of the invention, as Figure 5 and Figure 7 As shown, ultrasonic emission channels 20 corresponding to the lower guide section 16 and the upper guide section 17 are fixedly installed on the inner wall of the condenser cylinder 7. The lower guide section 16 and the upper guide section 17 are respectively connected to the corresponding ultrasonic emission channels 20. Ultrasonic generators 21 corresponding to the ultrasonic emission channels 20 are installed on the circumferential side of the condenser cylinder 7. The top of the upper guide section 17 is provided with an annular groove 22 coaxial with it. By setting an ultrasonic emission channel 20 and an ultrasonic generator 21 at the positions of the lower guide section 16 and the upper guide section 17 respectively, cooling water or coolant enters the lower guide section 16 through the condenser inlet pipe 18, then flows from bottom to top through each condenser channel 6 into the upper guide section 17, and then flows out through the condenser outlet pipe 19. During the circulation of cooling water or coolant, through the upper and lower distribution... Two ultrasonic generators 21 and an ultrasonic transmission channel 20 are used to ultrasonically treat the cooling water or coolant. The ultrasonic vibration of the cooling water or coolant causes micro-vibration in each condensation channel 6, which can accelerate the downward flow of condensate adhering to the outer wall of the condensation channel 6 to a certain extent, thereby improving the condensation effect of each condensation channel 6 on the top gas phase. The ultrasonic energy can be transferred to the cooling water or coolant, causing micro-vibration in the cooling water or coolant circulating through each condensation channel, which can effectively prevent the formation of scale on the inner wall of the condensation channel. At the same time, the scale loosened by the ultrasonic waves can be carried away by the cooling water in time. The "ultrasonic + small ball" design realizes online real-time descaling, which can effectively reduce the formation of scale on the inner wall of the condensation channel and ensure the heat exchange and condensation effect of each condensation channel.

[0046] In this embodiment of the invention, as Figure 7 As shown, the condensation channel 6 is connected between the lower guide section 16 and the upper guide section 17. The top of the upper guide section 17 is provided with an installation port 23 that communicates with its inner cavity. The installation port 23 is provided in a one-to-one correspondence with the condensation channel 6, and the installation port 23 is coaxial with the corresponding condensation channel 6. The diameter of the installation port 23 is the same as the inner diameter of the condensation channel 6. The gas phase channel is located between the condensation channel 6, the lower guide section 16, the upper guide section 17 and the condensation cylinder 7.

[0047] Example 2, based on Example 1, such as Figure 6 and Figure 8As shown, a small ball limiting assembly 24 is provided inside the condenser body 7. The small ball limiting assembly 24 includes a flow collector 25 installed on the top of the condenser body 7. The gas phase inlet pipe 8 of the secondary condenser 5 is connected to the flow collector 25 of the primary condenser 4 through a gas phase pipe 26. The gas phase pipe 26 ensures that the gas phase flowing out of the flow collector 25 of the primary condenser 4 enters the condenser body 7 of the secondary condenser 5 along the gas phase inlet pipe 8 of the secondary condenser 5. The combined action of the primary condenser 4 and the secondary condenser 5 can improve the condensation effect of the gas phase at the top of the column, thereby improving the concentration effect of ethylene glycol. The flow collector 25 of the secondary condenser 5 is connected to the vacuum system of the ethylene glycol concentration tower through a gas phase pipe 3. The uncondensed gas phase flows into the vacuum system of the ethylene glycol concentration tower through the gas phase pipe 3.

[0048] In this embodiment of the invention, as Figure 9 As shown, a support plate 27 is fixedly installed at the bottom of the flow collector 25. Both the support plate 15 and the support plate 27 are provided with a number of flow holes 28 arranged in a circumferential array. The flow holes 28 on the support plate 27 are used for gas phase passage, while the flow holes 28 on the support plate 15 are used for condensate passage. That is, the condensate generated after condensation in the condenser cylinder 7 is collected into the flow collector 14 through the lower flow holes 28, while the uncondensed gas phase enters the flow collector 25 through the upper flow holes 28. A sealing ring 29 that cooperates with the annular groove 22 is fixed at the bottom of the support plate 27 to increase the airtightness of the flow collector 25 and the top of the condenser cylinder 7.

[0049] The flow passage hole 28 on the support plate 15 is located outside the lower guide section 16, and the flow passage hole 28 on the support plate 27 is located outside the sealing ring 29. Several sealing plugs 30 located inside the sealing ring 29 are fixed at the bottom of the support plate 27. The sealing plugs 30 are tightly fitted with the corresponding mounting ports 23. That is, after the flow collector 25 is sealed on the top of the condenser cylinder 7, each sealing plug 30 is tightly fitted in the corresponding mounting port 23 on the top of the condenser cylinder 7 to ensure that the cooling water or coolant flowing from each condenser channel 6 into the upper guide section 17 cannot flow out along the mounting port 23, but can only flow out along the condensate outlet pipe 19.

[0050] In this embodiment of the invention, as Figure 9As shown, a support rod 31 is fixed at the bottom of the sealing plug 30 and located inside the condensation channel 6. A lower filter plate 32 and an upper filter plate 33 are fixed on the support rod 31 respectively. The lower filter plate 32 and the upper filter plate 33 must block the turbulence ball and ensure that the pressure drop when the cooling water or coolant passes through is as small as possible. The diameter of the lower filter plate 32 and the upper filter plate 33 is the same as the inner diameter of the condensation channel 6 to ensure that the lower filter plate 32 and the upper filter plate 33 can be assembled into the condensation channel 6. The turbulence ball is located between the lower filter plate 32 and the upper filter plate 33, so that the turbulence ball can only be between the lower filter plate 32 and the upper filter plate 33. The ball between the lower filter plate 32 and the upper filter plate 33 will jump and rotate under the action of the rising water flow. The turbulence ball is made of wear-resistant and elastic polymer material, and the density of the turbulence ball is the same as that of the coolant. The turbulence ball acts as a "turbulence component" to stir the originally stable laminar fluid to form turbulence, and thins the thermal resistance boundary layer on the surface of the pipe wall.

[0051] Under the induction of ultrasonic vibration, the turbulence-inducing spheres will generate slight collisions with the inner wall of the tube, which can promptly scrape off the deposits loosened by the ultrasonic waves and carry them away with the liquid flow. Due to the turbulence effect of the turbulence-inducing spheres and the disruption of the thermal resistance boundary layer by the ultrasonic waves, the heat transfer coefficient is higher than that of a purely static fluid. The ultrasonic waves used in this application have a frequency of 28-40kHz. This frequency band has strong cavitation force and can induce resonance in the spheres, enhancing the collision effect.

[0052] Traditional condensers require periodic shutdowns for chemical acid washing or high-pressure water jet cleaning. This design utilizes "ultrasound + small balls" to achieve online real-time descaling, effectively reducing the adhesion of calcium carbonate crystals to the inner wall of the condenser tubes. Scale-free tube walls mean low flow resistance, eliminating the need for the circulating pump to operate under overload to overcome the pressure drop caused by scaling. The density of the turbulence-inducing small balls in this application should be slightly greater than or close to that of the cooling water or coolant, including a density consistent with the cooling water or coolant. If the turbulence-inducing small balls are too heavy, the flowing cooling water or coolant cannot propel them into suspension; if they are too light, they will all be compressed at the upper filter plate 33, failing to create effective turbulence. Therefore, the turbulence-inducing small balls in this application can be made of wear-resistant and elastic polymer materials, such as Teflon or special sponge rubber.

[0053] Example 3, based on Examples 1 and 2, as follows: Figures 8 to 10As shown, a storage cylinder 34 is fixed to the top of the lower filter plate 32 of the first-stage condenser 4. Several strip-shaped flow ports are arranged in a circumferential array on the periphery of the storage cylinder 34. The diameter of the turbulence-inducing balls is larger than the width of the strip-shaped flow ports to ensure that the turbulence-inducing balls placed inside the storage cylinder 34 cannot leak out along the strip-shaped flow ports. A suspension element 35 is provided at the top of the storage cylinder 34. The suspension element 35 consists of a cleaning ring 36 and a limiting ring 37 fixedly connected. The outer diameter of the cleaning ring 36 is the same as the inner diameter of the condenser flow channel 6, and the outer diameter of the limiting ring 37 is the same as the inner diameter of the storage cylinder 34. The cleaning ring 36 is provided with cleaning surfaces 38, ... The upper inclined surface 39 and the lower inclined surface 40 are used to control the rebound motion of the turbulent turbulent spheres. During the continuous circulation of cooling water, the suspended components 35 in each condensation channel 6 of the first-stage condenser 4 are in a suspended state. The cleaning surface 38 on the suspended components 35 can dynamically clean the pipe walls of the condensation channel 6. The turbulent spheres will collide with the upper inclined surface 39 or the lower inclined surface 40, thereby increasing the motion amplitude of the turbulent spheres and the suspended components 35, which can further improve the condensation effect of each condensation channel 6. It should be noted that there is a set matching relationship between the effective density of the suspended component 35 and the design flow velocity. For example, when the upward flow velocity of the coolant reaches 0.8-1.2 m / s, the sum of the buoyancy force and the fluid lift force on the suspended component 35 is equal to its own weight.

[0054] After placing a certain number of turbulence-inducing balls into each storage cylinder 34, the entire ball limiting assembly 24 is then installed into the condenser cylinder 7. At this time, the turbulence-inducing balls in each storage cylinder 34 are confined between the lower filter plate 32 and the upper filter plate 33. During the ethylene glycol concentration process, cooling water or refrigerant flows through each condenser channel 6 in the condenser cylinder 7. Under the impact of the liquid flow on the turbulence-inducing balls and the action of ultrasound, the turbulence-inducing balls in each condenser channel 6 collide with the pipe wall to achieve micro-vibration. During the condensation process, the turbulence-inducing balls in each condenser channel 6 are in a suspended state, which can effectively prevent the turbulence-inducing balls from continuously accumulating at the bottom of the upper filter plate 33 and affecting the flow performance.

[0055] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0056] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An integrated system for high-efficiency recovery of ethylene glycol, comprising an ethylene glycol concentration tower (1), wherein the bottom of the ethylene glycol concentration tower (1) is equipped with a thermosiphon reboiler (2), and a reflux device (3) is provided on one side of the top of the ethylene glycol concentration tower (1); characterized in that, The reflux device (3) is equipped with a primary condenser (4) and a secondary condenser (5) above it. The reflux device (3) is used to receive the condensate from each condenser and partially reflux it back to the ethylene glycol concentration tower (1). The condensing temperature of the primary condenser (4) is controlled at 55.3℃, and the condensing temperature of the secondary condenser (5) is controlled at -10℃. The primary condenser (4) is used to receive and condense the top gas phase of the ethylene glycol concentration tower (1). The primary condenser (4) and the secondary condenser (5) each include at least two condensation channels (6), and the outer side of the condensation channels (6) is surrounded by a gas phase channel. The outer wall of the condensation channels (6) is coated with a nano-hydrophobic coating to improve the heat transfer coefficient. The condensation channel (6) is provided with a turbulence ball that moves with the liquid flow and slightly vibrates its wall. The coolant flowing in the condensation channel (6) increases the collision frequency between the turbulence ball and the inner wall of the condensation channel (6) by ultrasound, so as to increase the flow rate of the condensate adhering to the outer wall of the condensation channel (6).

2. The integrated system for high-efficiency ethylene glycol recovery according to claim 1, characterized in that, Both the primary condenser (4) and the secondary condenser (5) include a condenser body (7). The condenser body (7) is arranged vertically and its circumferential side is connected to a gas inlet pipe (8). The gas inlet pipe (8) is set close to the bottom of the condenser body (7). The gas inlet pipe (8) of the primary condenser (4) is connected to the top of the ethylene glycol concentration tower (1) through a gas inlet pipe (9).

3. The integrated system for high-efficiency ethylene glycol recovery according to claim 2, characterized in that, The reflux device (3) includes a horizontally arranged reflux cylinder (10). The top of the reflux cylinder (10) is connected to two condensate collection pipes, and the bottom of the reflux cylinder (10) is connected to a reflux pipe (11). The reflux pipe (11) is connected to the top of the ethylene glycol concentration tower (1). The bottom of the reflux cylinder (10) is connected to a branch pipe (12) for connecting to the light component cooler. A flow regulating valve (13) is fixedly installed on the branch pipe (12). The bottom of the condensate cylinder (7) is equipped with a flow collection hood (14) connected to the condensate collection pipe.

4. The integrated system for high-efficiency ethylene glycol recovery according to claim 2, characterized in that, A support plate (15) is fixed on the inner wall of the condenser cylinder (7) near the bottom. A hollow lower guide section (16) is installed on the top of the support plate (15). A hollow upper guide section (17) is provided inside the condenser cylinder (7) near the top. A condenser inlet pipe (18) and a condenser outlet pipe (19) are respectively installed on the circumferential side of the condenser cylinder (7). The condenser inlet pipe (18) is connected to the lower guide section (16), and the condenser outlet pipe (19) is connected to the upper guide section (17).

5. The integrated system for high-efficiency ethylene glycol recovery according to claim 4, characterized in that, An ultrasonic emission channel (20) corresponding to the lower guide section (16) and the upper guide section (17) is fixedly installed on the inner wall of the condenser cylinder (7). The lower guide section (16) and the upper guide section (17) are respectively connected to the corresponding ultrasonic emission channel (20). An ultrasonic generator (21) corresponding to the ultrasonic emission channel (20) is installed on the circumferential side of the condenser cylinder (7). An annular groove (22) coaxial with the upper guide section (17) is provided on the top of the upper guide section (17).

6. The integrated system for high-efficiency ethylene glycol recovery according to claim 5, characterized in that, The condensation channel (6) is connected between the lower guide section (16) and the upper guide section (17). The top of the upper guide section (17) is provided with an installation port (23) that communicates with its inner cavity. The installation port (23) is provided one-to-one with the condensation channel (6), and the installation port (23) is coaxial with the corresponding condensation channel (6). The diameter of the installation port (23) is the same as the inner diameter of the condensation channel (6). The gas phase channel is located between the condensation channel (6), the lower guide section (16), the upper guide section (17) and the condensation cylinder (7).

7. The integrated system for high-efficiency ethylene glycol recovery according to claim 6, characterized in that, The condenser cylinder (7) is provided with a small ball limiting assembly (24). The small ball limiting assembly (24) includes a flow collector hood two (25) installed on the top of the condenser cylinder (7). The gas phase inlet pipe (8) of the secondary condenser (5) is connected to the flow collector hood two (25) of the primary condenser (4) through a gas phase pipe two (26). The flow collector hood two (25) of the secondary condenser (5) is connected to the vacuum system of the ethylene glycol concentration tower through a gas phase pipe three.

8. The integrated system for high-efficiency ethylene glycol recovery according to claim 7, characterized in that, The bottom of the flow collector shroud 2 (25) is fixedly installed with a support plate 2 (27). Both the support plate 1 (15) and the support plate 2 (27) are provided with a number of flow holes (28) arranged in a circumferential array. The bottom of the support plate 2 (27) is fixed with a sealing ring (29) that cooperates with the annular groove (22). The flow hole (28) on the first support plate (15) is located outside the lower guide part (16), and the flow hole (28) on the second support plate (27) is located outside the sealing ring (29). Several sealing plugs (30) located inside the sealing ring (29) are fixed at the bottom of the second support plate (27). The sealing plugs (30) are tightly fitted with the corresponding mounting ports (23).

9. The integrated system for high-efficiency ethylene glycol recovery according to claim 8, characterized in that, The bottom of the sealing plug (30) is fixed with a support rod (31) located in the condensation channel (6). The support rod (31) is fixed with a lower filter plate (32) and an upper filter plate (33). The diameters of the lower filter plate (32) and the upper filter plate (33) are the same as the inner diameter of the condensation channel (6). The turbulence ball is located between the lower filter plate (32) and the upper filter plate (33). The turbulence ball is made of wear-resistant and elastic polymer material, and the density of the turbulence ball is the same as that of the coolant.

10. The integrated system for high-efficiency ethylene glycol recovery according to claim 9, characterized in that, The first-stage condenser (4) has a storage cylinder (34) fixed on the top of the lower filter plate (32). The storage cylinder (34) has a suspension element (35) on the top. The suspension element (35) consists of a cleaning ring (36) and a limiting ring (37) that are fixedly connected. The outer diameter of the cleaning ring (36) is the same as the inner diameter of the condensation channel (6). The outer diameter of the limiting ring (37) is the same as the inner diameter of the storage cylinder (34). The cleaning ring (36) is provided with a cleaning surface (38), an upper inclined surface (39) and a lower inclined surface (40). The upper inclined surface (39) and the lower inclined surface (40) are used for the rebound motion of the turbulent turbulent balls.

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