A glycol evaporator pressure control device

Abstract

This utility model discloses a pressure control device for an ethylene glycol evaporator in the field of polyester spinning. The device includes an evaporator with a heat medium inlet and outlet, and an ethylene glycol inlet and outlet. The heat medium inlet is connected to an inlet pipe, and two parallel pump-in pipes are connected to the end of the inlet pipe. Both pump-in pipes are connected to a second heat medium supply pipe, and each pump-in pipe is equipped with a heat medium pump. The outlet pipe is connected to a first and second heat medium recovery pipe in parallel. A side-connecting pipe is provided between the second heat medium recovery pipe and the second heat medium supply pipe. A temperature regulating valve is installed on the inlet pipe, and the first heat medium supply pipe is connected to the side of the pipe wall in front of the temperature regulating valve. This utility model fully utilizes the kinetic steam generated by the evaporator to maintain stable operation and repeatedly recycle it, saving heat energy wasted due to large fluctuations.

Description

Technical Field

[0001] This utility model belongs to the field of polyester spinning, and specifically relates to a pressure control device for an ethylene glycol evaporator. Background Technology

[0002] Currently, most polyester spinning equipment uses continuous spinning production. Since esterification and polycondensation are carried out in the production process using a vacuum system, multi-stage steam jet spraying devices are often used for vacuum extraction in the design and use of power steam. The problem is that most power steam generators have different outlet pressure control and heating methods, which makes vacuum extraction difficult in the polymerization process. Utility Model Content

[0003] The purpose of this invention is to provide a pressure control device for an ethylene glycol evaporator, which can make full use of the motive steam generated by the evaporator to maintain stable operation and reuse it repeatedly, reduce fluctuations in the vacuum system, and save the heat energy wasted due to large fluctuations.

[0004] The purpose of this utility model is achieved as follows: A pressure control device for an ethylene glycol evaporator includes an evaporator with a heat medium inlet and a heat medium outlet, and an ethylene glycol inlet and an ethylene glycol outlet. The heat medium inlet is connected to an inlet pipe, and the heat medium outlet is connected to a discharge pipe. Two parallel pump-in pipes are connected to the end of the inlet pipe, and the ends of both pump-in pipes are connected to a second heat medium supply pipe. Each of the two pump-in pipes is equipped with a heat medium pump. The end of the discharge pipe is connected to a first heat medium recovery pipe and a second heat medium recovery pipe in parallel. A side connecting pipe is provided between the second heat medium recovery pipe and the second heat medium supply pipe. A temperature regulating valve is provided on the inlet pipe, and the first heat medium supply pipe is connected to the side of the pipe wall in front of the temperature regulating valve.

[0005] In operation, this invention introduces hydrogenated terphenyl heat transfer oil (heat transfer medium) into the heat transfer medium inlet of the evaporator and introduces ethylene glycol into the evaporator through the ethylene glycol inlet. The liquid ethylene glycol and the hydrogenated terphenyl heat transfer oil exchange heat in the evaporator, causing the liquid ethylene glycol to evaporate into steam, which is then discharged through the ethylene glycol outlet, forming a continuous and stable power steam.

[0006] The pressure control device of this utility model for an ethylene glycol evaporator mainly monitors and adjusts the evaporator outlet pressure in real time through an evaporation pressure regulating valve. Combined with the coordinated operation of a multi-stage jet vacuum pump, condenser, and throttling valve, it ensures that the system maintains stable evaporation pressure and temperature under different loads. The core device for pressure control is the evaporator pressure regulating valve, which is installed on the evaporator outlet pipe. The evaporator pressure gauge is installed downstream of the valve, ensuring that the power steam of the multi-stage jet vacuum pump group is always maintained in a balanced state. Both the first and second heat transfer media are hydrogenated terphenyl heat transfer oil. Compared with the prior art, the beneficial effects of this utility model are: the dynamic regulation of the ethylene glycol evaporator steam in this utility model, when the following situations occur: 1. Heat load decreases → evaporation pressure drops → pressure regulating valve automatically opens wider; 2. Heat transfer medium temperature increases → evaporation pressure increases → pressure regulating valve automatically closes narrower (according to the different requirements of the multi-stage pump, the first and second heat transfer medium supply pipes are switched to ensure the heat required for evaporation). By continuously adjusting the valve opening, the evaporation pressure is maintained within a stable range of 105-150 kPa.

[0007] As a further improvement of this utility model, the ethylene glycol outlet is connected to a steam pipe, and a pressure regulating valve is installed on the steam pipe. The end of the steam pipe is connected to a multi-stage jet vacuum pump. A shut-off valve is installed on both sides of the steam pipe, before and after the pressure regulating valve. A parallel pipe is also provided on the side of the steam pipe, with both ends of the parallel pipe connected to the side of the steam pipe. The shut-off valve is also installed on the parallel pipe. The discharge volume of the power steam is adjusted by the pressure regulating valve.

[0008] As a further improvement of this utility model, a shut-off valve is provided on both sides of the inlet pipe, before and after the temperature regulating valve. A second parallel pipe is provided on the side of the inlet pipe, with both ends of the second parallel pipe connected to the side of the inlet pipe. The second parallel pipe is also equipped with a shut-off valve. The first heat medium supply pipe is connected to the inlet pipe between the temperature regulating valve and the front shut-off valve. The shut-off valves facilitate the adjustment of the opening and closing of the heat medium inlet. The first heat medium supply pipe supplies heat medium to the evaporator.

[0009] As a further improvement of this utility model, the second heat medium recovery pipe, the second heat medium supply pipe, and the two pump inlet pipes are all connected to the side of the low-level pipe via a branch pipe. The end of the low-level pipe is connected to the heat medium low-level tank, and a shut-off valve is provided on the branch pipe. The heat medium can be transferred to the heat medium low-level tank through the branch pipe.

[0010] As a further improvement of this utility model, a drain pipe is connected to the side of the inlet pipe, and a shut-off valve is provided on the drain pipe. The drain pipe can be used to drain the heat medium that enters from the second heat medium supply pipe.

[0011] As a further improvement of this utility model, the side of the second heat medium recovery pipe is connected to the high-level pipe, and the end of the high-level pipe is connected to the high-level heat medium tank. A discharge pipe is connected to the side of the steam pipe, and the end of the discharge pipe is connected to the side of the second heat medium recovery pipe. A shut-off valve is provided on the discharge pipe. The heat medium can be discharged to the high-level heat medium tank through the second heat medium recovery pipe.

[0012] As a further improvement of this invention, a pressure relief pipe is also connected to the evaporator. This pipe allows excess pressurized steam to be released into the emergency tank.

[0013] As a further improvement of this utility model, shut-off valves are provided on the pump inlet pipe, the first heat medium recovery pipe, the first heat medium supply pipe, the second heat medium supply pipe, and the second heat medium recovery pipe. The shut-off valves facilitate the control of the pipeline opening and closing.

[0014] As a further improvement of this utility model, the evaporator is provided with a vertical partition plate 1 inside, a horizontal partition plate 2 is provided on the left side of the partition plate 1 inside the evaporator, and several U-shaped heating tubes are provided on the right side of the partition plate 1 inside the evaporator. Several baffles are arranged vertically and horizontally corresponding to each heating tube inside the evaporator. The heat medium enters the evaporator and then flows from the heating tubes to above the partition plate 2. Ethylene glycol enters the right side of the partition plate 1 of the evaporator and is deflected by the baffles, allowing it to fully exchange heat with the heat medium. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model.

[0016] Figure 2 for Figure 1 A magnified view of a portion of the image.

[0017] Figure 3 for Figure 1 A magnified view of a portion of the image.

[0018] Figure 4 This is a schematic diagram of the evaporator.

[0019] The components are as follows: 1. Evaporator; 2. Heat medium inlet; 3. Heat medium outlet; 4. Ethylene glycol inlet; 5. Ethylene glycol outlet; 6. Inlet pipe; 7. Discharge pipe; 8. Pump inlet pipe; 9. Second heat medium supply pipe; 10. Heat medium pump; 11. First heat medium recovery pipe; 12. Second heat medium recovery pipe; 13. Side connecting pipe one; 14. Temperature regulating valve; 15. First heat medium supply pipe; 16. Steam pipe; 17. Pressure regulating valve; 18. Shut-off valve; 19. Parallel pipe one; 20. Parallel pipe two; 21. Branch pipe one; 22. Low-level pipe; 23. Heat medium low-level tank; 24. Drain pipe; 25. Shut-off valve; 26. High-level pipe; 27. Heat medium high-level tank; 28. Discharge pipe; 29. ​​Shut-off valve; 30. Pressure relief pipe; 31. Divider plate one; 32. Divider plate two; 33. Heating pipe; 34. Baffle plate. Detailed Implementation

[0020] like Figure 1-4 The diagram shows a pressure control device for an ethylene glycol evaporator, comprising an evaporator 1, a heat medium inlet 2 and a heat medium outlet 3, an ethylene glycol inlet 4 and an ethylene glycol outlet 5, a heat medium inlet 2 connected to an inlet pipe 6, a heat medium outlet 3 connected to a discharge pipe 7, two parallel pumping pipes 8 connected to the end of the inlet pipe 6, both ends of which are connected to a second heat medium supply pipe 9, and a heat medium pump 10 installed on each of the two pumping pipes 8, and a first heat medium recovery pipe 11 and a second heat medium recovery pipe 12 connected to the end of the discharge pipe 7, with a side connecting pipe 13 between the second heat medium recovery pipe 12 and the second heat medium supply pipe 9, a temperature regulating valve 14 installed on the inlet pipe 6, and a first heat medium supply pipe 15 connected to the side wall of the inlet pipe 6 in front of the temperature regulating valve 14. A shut-off valve 18 is installed on the pump inlet pipe 8, the first heat medium recovery pipe 11, the first heat medium supply pipe 15, the second heat medium supply pipe 9, and the second heat medium recovery pipe 12. The shut-off valve 18 facilitates the control of the pipeline opening and closing.

[0021] Ethylene glycol outlet 5 is connected to a steam pipe 16, which is equipped with a pressure regulating valve 17. The end of the steam pipe 16 is connected to a multi-stage jet vacuum pump. A shut-off valve 18 is located on both sides of the steam pipe 16, before and after the pressure regulating valve 17. A parallel pipe 19 is also located on the side of the steam pipe 16, with both ends connected to the side of the steam pipe 16. The shut-off valve 18 is also located on the parallel pipe 19. The pressure regulating valve 17 is used to adjust the discharge rate of the power steam. A shut-off valve 18 is located on both sides of the inlet pipe 6, before and after the temperature regulating valve 14. A parallel pipe 20 is located on the side of the inlet pipe 6, with both ends connected to the side of the inlet pipe 6. The shut-off valve 18 is located on the first heat medium supply pipe 15, which is connected to the inlet pipe 6 between the temperature regulating valve 14 and the front shut-off valve 18. The shut-off valve 18 facilitates the opening and closing of the heat medium inlet. The first heat medium supply pipe 15 supplies heat medium to the evaporator 1.

[0022] The second heat medium recovery pipe 12, the second heat medium supply pipe 9, and the two pump inlet pipes 8 are all connected to the side of the low-level pipe 22 via a branch pipe 21. The end of the low-level pipe 22 is connected to the heat medium low-level tank 23. A shut-off valve 18 is installed on the branch pipe 21. Heat medium can be transferred to the heat medium low-level tank 23 through the branch pipe. An vent pipe 24 is connected to the side of the inlet pipe 6. A shut-off valve 25 is installed on the vent pipe 24. Heat medium entering from the second heat medium supply pipe 9 can be vented through the vent pipe 24. The side of the second heat medium recovery pipe 12 is connected to the high-level pipe 26. The end of the high-level pipe 26 is connected to the heat medium high-level tank 27. A discharge pipe 28 is connected to the side of the steam pipe 16. The end of the discharge pipe 28 is connected to the side of the second heat medium recovery pipe 12. A shut-off valve 29 is installed on the discharge pipe 28. Heat medium can be vented to the heat medium high-level tank 27 through the second heat medium recovery pipe 12.

[0023] Evaporator 1 is also connected to a pressure relief pipe 30. Excess pressurized steam can be released to the emergency tank via the pressure relief pipe 30. Evaporator 1 has a vertical partition plate 31 inside, a horizontal partition plate 32 to the left of partition plate 31, and several U-shaped heating tubes 33 to the right of partition plate 31. Corresponding to each heating tube 33, several staggered baffles 34 are arranged inside evaporator 1. The heat transfer medium enters evaporator 1 and flows from the heating tubes 33 to above partition plate 32. Ethylene glycol enters the evaporator 1 to the right of partition plate 31 and is then deflected by the baffles 34, ensuring sufficient heat exchange with the heat transfer medium.

[0024] When this utility model is in operation, hydrogenated terphenyl heat transfer oil (heat transfer medium) is introduced into the heat transfer medium inlet 2 of the evaporator 1, and ethylene glycol is introduced into the evaporator 1 through the ethylene glycol inlet 4. The liquid ethylene glycol and the hydrogenated terphenyl heat transfer oil exchange heat in the evaporator 1, causing the liquid ethylene glycol to evaporate into steam, which is then discharged through the ethylene glycol outlet 5, forming a continuous and stable power steam.

[0025] The pressure control device of this utility model for the ethylene glycol evaporator 1 mainly monitors and adjusts the outlet pressure of evaporator 1 in real time through the evaporation pressure regulating valve 17. Combined with the coordinated operation of the multi-stage jet vacuum pump, condenser, and throttling valve, it ensures that the system maintains stable evaporation pressure and temperature under different loads. The core device for pressure control is the evaporator 1 pressure regulating valve 17, which is installed on the outlet pipe of evaporator 1. The evaporator 1 pressure gauge is installed after the valve, ensuring that the motive steam of the multi-stage jet vacuum pump group is always maintained in a balanced state. Both the first and second heat transfer media are hydrogenated terphenyl heat transfer oil. This utility model can be used for continuous polymerization and semi-continuous polymerization production. The outlet of evaporator 1 is equipped with a motive steam pressure regulating valve group and a remote pressure gauge. The heat transfer media heats the primary and secondary heat transfer media in combination to achieve stable and timely output of motive steam from evaporator 1. The significant advantages of this utility model are: low investment cost; energy saving; small fluctuations in the vacuum system; and easy control and improvement of product quality.

[0026] This utility model is not limited to the above embodiments. Based on the technical solutions disclosed in this utility model, those skilled in the art can make some substitutions and modifications to some of the technical features without creative labor, and these substitutions and modifications are all within the protection scope of this utility model.

Claims

1. A kind of ethylene glycol evaporator pressure control device, including evaporator, the hot medium import and hot medium export are provided on the evaporator, evaporator is also equipped with ethylene glycol import and ethylene glycol export, it is characterized in that, The heat medium inlet is connected to the inlet pipe, and the heat medium outlet is connected to the outlet pipe. The end of the inlet pipe is connected to two parallel pump inlet pipes, and the ends of both pump inlet pipes are connected to the second heat medium supply pipe. Each of the two pump inlet pipes is equipped with a heat medium pump. The end of the outlet pipe is connected to a first heat medium recovery pipe and a second heat medium recovery pipe in parallel. A side connecting pipe is provided between the second heat medium recovery pipe and the second heat medium supply pipe. The inlet pipe is equipped with a temperature regulating valve, and the first heat medium supply pipe is connected to the side of the pipe wall in front of the temperature regulating valve.

2. A glycol evaporator pressure control device according to claim 1, wherein, The ethylene glycol outlet is connected to a steam pipe, which is equipped with a pressure regulating valve. The end of the steam pipe is connected to a multi-stage jet vacuum pump. A shut-off valve is provided on both sides of the steam pipe, before and after the pressure regulating valve. A parallel pipe is also provided on the side of the steam pipe, with both ends of the parallel pipe connected to the side of the steam pipe. The parallel pipe is equipped with a shut-off valve.

3. A glycol evaporator pressure control device according to claim 1 or 2, wherein The inlet pipe is equipped with a shut-off valve on both the front and rear sides of the temperature regulating valve. A second parallel pipe is provided on the side of the inlet pipe, and both ends of the second parallel pipe are connected to the side of the inlet pipe. The second parallel pipe is equipped with a shut-off valve. The first heat medium supply pipe is connected to the inlet pipe between the temperature regulating valve and the front shut-off valve.

4. A glycol evaporator pressure control device according to claim 1 or 2, wherein The second heat medium recovery pipe, the second heat medium supply pipe, and the two pump inlet pipes are all connected to the side of the low-level pipe via a branch pipe. The end of the low-level pipe is connected to the heat medium low-level tank. A shut-off valve is provided on the branch pipe.

5. A glycol evaporator pressure control apparatus as defined in claim 1 or 2, wherein The inlet pipe is connected to an outlet pipe on its side, and the outlet pipe is equipped with a shut-off valve.

6. A glycol evaporator pressure control apparatus as set forth in claim 2 wherein, The side of the second heat medium recovery pipe is connected to the high-level pipe, and the end of the high-level pipe is connected to the high-level heat medium tank. The side of the steam pipe is connected to the discharge pipe, and the end of the discharge pipe is connected to the side of the second heat medium recovery pipe. A shut-off valve is provided on the discharge pipe.

7. A glycol evaporator pressure control apparatus as defined in claim 1 or 2, wherein The evaporator is also connected to a pressure relief pipe.

8. A pressure control device for an ethylene glycol evaporator according to claim 1 or 2, characterized in that, The pump inlet pipe, the first heat medium recovery pipe, the first heat medium supply pipe, the second heat medium supply pipe, and the second heat medium recovery pipe are all equipped with shut-off valves.

9. A glycol evaporator pressure control apparatus as defined in claim 1 or 2, wherein The evaporator is equipped with a vertical partition plate 1 inside, a horizontal partition plate 2 is located to the left of partition plate 1 inside the evaporator, and several U-shaped heating tubes are located to the right of partition plate 1 inside the evaporator. Several baffles are arranged vertically and horizontally corresponding to each heating tube inside the evaporator.

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