Vacuum automatic dehydration system

Abstract

The utility model relates to a vacuum automatic dehydration system which comprises a vacuum condenser, a dehydration tank and a Roots water ring vacuum unit, a first stop valve is arranged on a gas phase outlet pipeline of the vacuum condenser, and a second stop valve is arranged on a gas phase outlet pipeline of the dehydration tank. According to the technical scheme, a condensate tank is arranged below the vacuum condenser, the height difference between the condensate tank and the vacuum condenser is at least 10 m, a submerged pipe is arranged at the bottom of the vacuum condenser, an overflow pipe is arranged on the upper portion of the side wall of the condensate tank, a bypass branch is connected between the inlet side of the first stop valve and the outlet side of the second stop valve, and a third stop valve is arranged on the bypass branch. A pressure gauge and a nitrogen pressure supplementing pipeline are arranged at the top of the dehydration tank, a fourth stop valve is arranged on the nitrogen pressure supplementing pipeline, a liquid level meter is arranged on the lower portion of the side wall of the dehydration tank, and a drainage pipe is arranged at the bottom of the dehydration tank and provided with a fifth stop valve. The system solves the problem of manual drainage, is high in dehydration efficiency, avoids the failure of the vacuum unit, and reduces the equipment failure rate and the labor intensity of workers.

Description

Technical Field

[0001] The utility model relates to the technical field of polyether polyol production equipment, in particular to a vacuum automatic dehydration system. Background Art

[0002] Polyether polyols are an important chemical raw material, typically produced through a ring-opening polymerization reaction between an initiator and an epoxide in the presence of a catalyst. They exhibit good solubility, low viscosity, and excellent flexibility and elasticity, making them primarily used in industries such as polyurethane foam, adhesives, and coatings. Vacuum dehydration is a crucial step in the synthesis of polyether polyols, used to remove moisture from the reaction and neutralization steps, thereby ensuring product quality. Vacuum dehydration currently utilizes a Roots water ring vacuum unit to extract the reaction gases, which are then condensed in a vacuum condenser and dehydration tank before being exhausted through the Roots water ring vacuum unit.

[0003] However, the following problems exist during the working process: if the water is not drained manually during operation, it will enter the vacuum unit and cause the vacuum unit to malfunction, which increases the equipment failure rate and labor intensity, and is not conducive to stable production. Utility Model Content

[0004] The purpose of this utility model is to provide a vacuum automatic dehydration system with reasonable configuration and reliable use, solve the problem of manual drainage, ensure the continuous dehydration process, timely discharge, high dehydration efficiency, avoid malfunction of the vacuum unit, reduce equipment failure rate and staff labor intensity.

[0005] The technical solution of the utility model is:

[0006] A vacuum automatic dehydration system comprises a vacuum condenser, a dehydration tank connected to the gas phase outlet pipeline of the vacuum condenser, and a Roots water ring vacuum unit connected to the gas phase outlet pipeline of the dehydration tank. The gas phase outlet pipeline of the vacuum condenser is provided with a first shut-off valve, and the gas phase outlet pipeline of the dehydration tank is provided with a second shut-off valve. The technical key points are: a condensate tank with a height difference of at least 10 meters is provided below the vacuum condenser, a submerged pipe inserted into the condensate tank is provided at the bottom of the vacuum condenser, and a liquid tank is provided on the side wall of the condensate tank. An overflow pipe is provided in the dehydration tank, a bypass branch is connected between the inlet side of the first shut-off valve and the outlet side of the second shut-off valve, and a third shut-off valve is provided on the bypass branch, a pressure gauge and a nitrogen pressure-compensating pipeline are provided on the top of the dehydration tank, a fourth shut-off valve which is activated according to the feedback information of the pressure gauge is provided on the nitrogen pressure-compensating pipeline, a liquid level gauge is provided on the lower part of the side wall of the dehydration tank, a drain pipe is provided at the bottom of the dehydration tank, and a fifth shut-off valve which is activated according to the feedback information of the liquid level gauge is provided on the drain pipe, and the lower ends of the overflow pipe and the drain pipe are respectively inserted into the sewage collection ditch.

[0007] The above-mentioned vacuum automatic dehydration system has a partition opposite to the gas direction in the dehydration tank, and the gas rises to the top of the dehydration tank through the lower edge of the partition. The top of the dehydration tank is equipped with a demisting mesh layer.

[0008] In the above-mentioned vacuum automatic dehydration system, the outer periphery of the demisting net layer is fixedly connected to the inner wall of the dehydration tank, and a vibrator is fixed on the upper edge of the demisting net layer, which causes the droplets to fall quickly through periodic vibration.

[0009] The beneficial effects of the utility model are:

[0010] 1. Under the action of the Roots water ring vacuum unit, the vacuum gas phase enters the vacuum condenser, the high-temperature gas is cooled and separated, and the separated liquid enters the condensate tank smoothly under vacuum state. A minimum height difference is set between the vacuum condenser and the condensate tank, and the pressure remains stable during the gas-liquid separation process.

[0011] 2. A dehydration tank is set before entering the vacuum unit to prevent water from entering the Roots water ring vacuum unit. By setting a pressure gauge, liquid level gauge, nitrogen pressure-compensating pipeline and corresponding shut-off valve group, the shut-off valve group can be switched on and off according to the set conditions to achieve automatic vacuum drainage, thereby reducing the equipment failure rate, reducing the labor intensity of the staff, and ensuring the stable operation of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the structural composition of the present utility model.

[0013] In the figure: 1. Vacuum condenser, 2. Gas phase outlet pipeline, 3. Bypass branch, 4. Third shut-off valve, 5. Second shut-off valve, 6. Gas phase outlet pipeline, 7. Fourth shut-off valve, 8. Nitrogen pressure boosting pipeline, 9. Roots water ring vacuum unit, 10. Dehydration tank, 11. Liquid level gauge, 12. Fifth shut-off valve, 13. Partition, 14. Pressure gauge, 15. Demisting mesh layer, 16. Vibrator, 17. First shut-off valve, 18. Submerged pipe, 19. Condensate tank, 20. Overflow pipe, 21. Drain pipe. DETAILED DESCRIPTION

[0014] The utility model is described in detail below with reference to the accompanying drawings.

[0015] like Figure 1 As shown, the vacuum automatic dehydration system includes a vacuum condenser 1, a dehydration tank 10 connected to the gas phase outlet pipeline 2 of the vacuum condenser 1, and a Roots water ring vacuum unit 9 connected to the gas phase outlet pipeline 6 of the dehydration tank 10. The gas phase outlet pipeline 2 of the vacuum condenser 1 is provided with a first shut-off valve 17, and the gas phase outlet pipeline 6 of the dehydration tank 10 is provided with a second shut-off valve 5.

[0016] Below the vacuum condenser 1 is a condensate tank 19, 12 meters above sea level. A submerged pipe 18 is installed at the bottom of the vacuum condenser 1, inserted into the condensate tank 19. An overflow pipe 20 is installed on the upper sidewall of the condensate tank 19. A bypass branch 3 is connected between the inlet of the first shut-off valve 17 and the outlet of the second shut-off valve 5, and a third shut-off valve 4 is installed on the bypass branch 3. A pressure gauge 14 and a nitrogen pressure-compensating line 8 are installed on the top of the dehydration tank 10. A fourth shut-off valve 7 is installed on the nitrogen pressure-compensating line 8, which operates based on feedback from the pressure gauge. A liquid level gauge 11 is installed on the lower sidewall of the dehydration tank 10. A drain pipe 21 is installed at the bottom of the dehydration tank 10, and a fifth shut-off valve 12 is installed on the drain pipe 21, which operates based on feedback from the liquid level gauge. The lower ends of the overflow pipe 20 and drain pipe 21 are respectively inserted into the sewage collection ditch.

[0017] In this embodiment, to enhance gas-liquid separation and improve separation efficiency, a partition 13 is installed within the dehydration tank 10, facing the direction of the gas. Gas passes through the lower edge of partition 13 and rises to the top of the dehydration tank 10. A demisting mesh layer 15 is built into the top of the dehydration tank 10. The outer periphery of the demisting mesh layer 15 is fixedly connected to the inner wall of the dehydration tank 10, and a vibrator 16 is fixed to the upper edge of the demisting mesh layer 15. This periodic vibration causes liquid droplets to fall rapidly.

[0018] Working principle:

[0019] During operation, the gas phase pipe at the top of the reactor is connected to the vacuum condenser 1. Under the action of the Roots water ring vacuum unit 9, the vacuum gas phase enters the vacuum condenser 1. The vacuum condenser 1 is cooled with circulating water. During the production process, the vacuum gas at a temperature of 100-120°C is cooled and separated. After cooling and separation, the gas phase enters the dehydration tank 10, and the liquid phase enters the condensate tank 19. The condensate is controlled by continuous water injection and overflow to ensure stable operation of the vacuum system pressure at -97±2Kpa. The overflow liquid enters the sewage treatment system after passing through the sewage collection ditch.

[0020] The gas phase is intercepted and separated in the dehydration tank 10 by the partition 13 and the demisting mesh layer 15 before entering the Roots water ring vacuum unit 9. When the liquid level in the dehydration tank 10 reaches the upper limit of 30%, the first shut-off valve 17 and the second shut-off valve 5 are closed, and the third shut-off valve 4 and the fourth shut-off valve 7 are opened. When the pressure meets the requirement of 30kPa, the fourth shut-off valve 7 is closed and the fifth shut-off valve 12 is opened for automatic drainage. When the liquid level in the dehydration tank 10 reaches 0% and the pressure is less than 5kPa, the fifth shut-off valve 12 and the third shut-off valve 4 are closed, and the first shut-off valve 17 and the second shut-off valve 5 are opened, returning to the initial dehydration state.

[0021] The above embodiments of the present invention are described in detail. However, the above contents are only preferred embodiments of the present invention and should not be considered as limiting the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A vacuum automatic dehydration system comprising a vacuum condenser, a dehydration tank connected to a gas phase outlet pipeline of the vacuum condenser, and a Roots water ring vacuum unit connected to the gas phase outlet pipeline of the dehydration tank, wherein a first shut-off valve is provided on the gas phase outlet pipeline of the vacuum condenser, and a second shut-off valve is provided on the gas phase outlet pipeline of the dehydration tank, characterized in that: A condensate tank with a height difference of at least 10 meters is provided below the vacuum condenser, a submerged pipe inserted into the condensate tank is provided at the bottom of the vacuum condenser, an overflow pipe is provided on the upper part of the side wall of the condensate tank, a bypass branch is connected between the inlet side of the first shut-off valve and the outlet side of the second shut-off valve, and a third shut-off valve is provided on the bypass branch, a pressure gauge and a nitrogen pressure-compensating pipeline are provided on the top of the dehydration tank, a fourth shut-off valve is provided on the nitrogen pressure-compensating pipeline and is actuated according to feedback information from the pressure gauge, a liquid level gauge is provided on the lower part of the side wall of the dehydration tank, a drain pipe is provided at the bottom of the dehydration tank and a fifth shut-off valve is provided on the drain pipe and is actuated according to feedback information from the liquid level gauge, and the lower ends of the overflow pipe and the drain pipe are respectively inserted into the sewage collection ditch.

2. The vacuum automatic dehydration system according to claim 1, characterized in that: The dehydration tank is provided with a partition opposite to the direction of gas. The gas rises to the top of the dehydration tank through the lower edge of the partition. The top of the dehydration tank is built with a demisting net layer.

3. The vacuum automatic dehydration system according to claim 1, characterized in that: The outer periphery of the demisting net layer is connected and fixed to the inner wall of the dehydration tank, and a vibrator is fixed on the upper edge of the demisting net layer.

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