Industrial continuous dewatering vacuum system and method of operation

Abstract

The application relates to the field of continuous dehydration systems, and discloses an industrial continuous dehydration vacuum system and a working method. The system comprises a front-stage vacuum circuit and a rear-stage vacuum circuit. Two liquid ring vacuum pumps are connected in series. The front-stage vacuum pump adopts conventional water as sealing liquid, and the rear-stage vacuum pump adopts a high-boiling-point liquid dissolved in water as working liquid. The front-stage vacuum pump provides negative pressure, and a heating source is used to remove a small amount of water in the working liquid in time, so that the vacuum degree of a production device is ensured. Meanwhile, an automatic control process scheme is adopted, so that the purpose of continuous and stable dehydration under various vacuum conditions is achieved. The continuous dehydration vacuum system provided by the application is reliable in operation, has strong adaptability to the change of water vapor content in extracted gas, produces a small amount of waste water, can meet various vacuum working conditions and continuous operation.

Description

Technical Field

[0001] This invention relates to the field of continuous dehydration system technology, specifically to an industrial continuous dehydration vacuum system and its operating method. Background Technology

[0002] In industrial production, especially in chemical and pharmaceutical manufacturing, excess moisture needs to be removed. Vacuum systems are often used to lower the evaporation pressure, thereby reducing the temperature during dehydration and protecting the product from high temperatures. This is particularly crucial for the continuous production of easily polymerizable or high-boiling-point products. Controlling the moisture content, reducing temperature to prevent polymerization, and balancing dehydration efficiency with energy conservation are all essential. Therefore, the selection of a vacuum pump is critical. Since water in the product exists as water vapor under high vacuum and is difficult to completely remove, it inevitably enters the vacuum system, negatively impacting its operation. Currently, there are generally five types of dehydration vacuum systems: water ring vacuum pumps, water jet vacuum pumps, Roots water ring units, steam jet pumps, and reciprocating vacuum pumps.

[0003] However, each of the above dehydration vacuum systems has its own drawbacks:

[0004] 1. Conventional water ring vacuum pumps use water as the sealing fluid. The ultimate vacuum is limited by the saturated vapor pressure of water and can generally only reach 2000 Pa (absolute pressure), which cannot meet the vacuum requirements of various working conditions.

[0005] 2. Water jet vacuum pumps consume a lot of water, have low efficiency, and can only achieve a vacuum level of 8000pa (absolute pressure), which cannot meet the vacuum requirements of various working conditions.

[0006] 3. Although the Roots water ring vacuum unit can achieve various vacuum conditions, the equipment is relatively complex and difficult to maintain. It also has requirements on the water vapor content in the pumped gas and has poor adaptability to fluctuations in water vapor content during the dehydration process, making it difficult to ensure continuous operation.

[0007] 4. Although steam jet pumps can achieve various vacuum conditions, they produce a large amount of wastewater, which can easily cause environmental problems.

[0008] 5. Although reciprocating vacuum pumps can achieve various vacuum conditions, they have many vulnerable parts and a high failure rate. They also have requirements on the water vapor content in the pumped gas and are not very adaptable to fluctuations in water vapor content during the dehydration process, making it difficult to ensure continuous operation. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides an industrial continuous dehydration vacuum system and its operating method, which is reliable in operation, highly adaptable to changes in the water vapor content of the pumped gas, generates little wastewater, and can meet various vacuum conditions and continuous operation requirements.

[0010] This invention employs two liquid ring vacuum pumps connected in series. The first-stage vacuum pump uses conventional water as the sealing fluid, while the second-stage vacuum pump uses a high-boiling-point liquid that is soluble in water as the working fluid. The negative pressure provided by the first-stage vacuum pump, combined with a heating source, allows for the timely removal of small amounts of water from the working fluid, ensuring the vacuum level of the production unit. Simultaneously, an automated control process is employed to achieve continuous and stable dehydration under various vacuum conditions.

[0011] To achieve the above objectives, the present invention is implemented through the following technical solution: an industrial continuous dehydration vacuum system, comprising a pre-stage vacuum circuit and a post-stage vacuum circuit;

[0012] The pre-vacuum circuit includes:

[0013] The fore-vacuum pump is used to create an initial vacuum, provide negative pressure for the subsequent buffer tank, and remove moisture and non-condensable gases from the subsequent buffer tank in a timely manner.

[0014] A pre-stage buffer tank, which is connected to the outlet of the pre-stage vacuum pump, is used to stabilize the pumped liquid and discharge non-condensable gases.

[0015] The inlet of the pre-stage heat exchanger is connected to the pre-stage buffer tank, and the outlet is connected to the pre-stage vacuum pump. It is used to cool the hot liquid discharged by the pre-stage vacuum pump.

[0016] The subsequent vacuum circuit includes:

[0017] A post-vacuum pump is used to further improve the vacuum level based on the pre-vacuum pump, and the inlet end of the post-vacuum pump is connected to the production device.

[0018] A post-stage buffer tank is connected to the outlet of the post-stage vacuum pump to stabilize the pumped liquid and discharge moisture and non-condensable gases. The post-stage buffer tank is connected to the inlet of the pre-stage vacuum pump.

[0019] The downstream heat exchanger has its inlet connected to the downstream buffer tank and its outlet connected to the downstream vacuum pump, and is used to cool the hot liquid discharged by the downstream vacuum pump.

[0020] Preferably, the pre-buffer tank is connected to a vent pipe for discharging the gas inside the pre-buffer tank.

[0021] Preferably, the pre-stage buffer tank is equipped with a drain control valve and a pre-stage level gauge, and the drain control valve and the pre-stage level gauge are linked for control.

[0022] Preferably, the pre-buffer tank is provided with a tap water inlet, and a tap water inlet valve is provided on the tap water inlet pipeline.

[0023] Preferably, the pre-heat exchanger is provided with a cooling water inlet and a cooling water outlet, a cooling water inlet valve is provided on the cooling water inlet pipe, and a cooling water return valve is provided on the cooling water outlet pipe.

[0024] Preferably, a pre-stage liquid supply valve is provided on the pipeline connecting the pre-stage vacuum pump and the pre-stage heat exchanger, a pre-stage venting valve is provided on the pipeline connecting the pre-stage vacuum pump and the pre-stage buffer tank, and a pre-stage inlet valve is provided on the pipeline connecting the pre-stage vacuum pump and the post-stage buffer tank.

[0025] Preferably, the downstream buffer tank is connected to a working fluid inlet, a working fluid inlet control valve is installed on the working fluid inlet pipeline, and a downstream level gauge is installed in the downstream buffer tank. The working fluid inlet control valve is linked to the downstream level gauge for control.

[0026] Preferably, the downstream buffer tank is provided with a heating source pipeline, the downstream buffer tank is provided with a downstream thermometer, the inlet of the heating source pipeline of the downstream buffer tank is provided with a heating source inlet control valve, the outlet of the heating source pipeline of the downstream buffer tank is provided with a heating source return valve, and the heating source inlet control valve is linked to the downstream thermometer for control.

[0027] Preferably, the downstream heat exchanger is provided with a low-temperature water inlet and a low-temperature water outlet, a low-temperature water inlet valve is provided on the low-temperature water inlet pipe, and a low-temperature water return valve is provided on the low-temperature water outlet pipe.

[0028] Preferably, a downstream inlet control valve is provided on the pipeline connecting the downstream vacuum pump and the production device, and a vacuum gauge is provided on the production device. The downstream inlet control valve and the vacuum gauge are linked for control.

[0029] Preferably, a post-stage exhaust valve is provided on the pipeline connecting the post-stage vacuum pump and the post-stage buffer tank.

[0030] Preferably, a downstream circulation pump is provided between the downstream vacuum pump and the downstream heat exchanger, and a downstream liquid supply valve is provided on the pipeline connecting the downstream circulation pump and the downstream heat exchanger.

[0031] This invention provides a method for operating the above-described continuous dehydration vacuum system, comprising the following steps:

[0032] S1. Open the working fluid inlet control valve, add working fluid to the downstream buffer tank, and set the working fluid inlet control valve and the downstream buffer tank level gauge to be linked control. At the same time, set the interlock value of the downstream level gauge to automatically replenish the working fluid.

[0033] S2. Open the heating source return valve and set the heating source inlet control valve and the downstream thermometer to be linked for control. At the same time, set the interlock value of the downstream thermometer to automatically control the temperature and remove the moisture in the downstream buffer tank.

[0034] S3. Open the tap water inlet valve and add tap water to the upstream buffer tank. When the upstream level gauge shows 20-80%, close the tap water inlet valve and set the drain control valve and the upstream level gauge to be linked. At the same time, set the interlock value of the upstream level gauge to automatically drain the water and ensure the stability of the upstream buffer tank level.

[0035] S4. Open the pre-stage inlet valve, pre-stage exhaust valve, pre-stage supply valve, cooling water inlet valve, and cooling water return valve in sequence, and then start the pre-stage vacuum pump.

[0036] S5. Set the downstream inlet control valve and the vacuum gauge of the production unit to be linked for control, and set the interlock value of the vacuum gauge of the production unit to obtain a stable vacuum in the production unit.

[0037] S6. Open the downstream exhaust valve, downstream supply valve, cryogenic water inlet valve, and cryogenic water return valve in sequence, and then open the downstream circulation pump and downstream vacuum pump in sequence.

[0038] Preferably, in step S1, during the operation of the vacuum system, the working fluid will be lost. To replenish the lost working fluid, the working fluid inlet control valve and the downstream level gauge are interlocked to automatically replenish the working fluid and ensure the stability of the downstream buffer tank level.

[0039] Preferably, in step S2, during the operation of the vacuum system, a small amount of water vapor will enter the downstream vacuum pump and the downstream buffer tank in the production device, and be converted into liquid water, affecting the stability of the vacuum degree of the production device. The heating source inlet control valve and the downstream thermometer are interlocked to automatically control the temperature and remove the water in the downstream buffer tank.

[0040] Preferably, in step S3, during the operation of the vacuum system, the water removed from the downstream buffer tank will enter the upstream buffer tank through the upstream vacuum pump, causing the liquid level in the upstream buffer tank to rise. The drain control valve is interlocked with the upstream liquid level gauge to automatically drain the water and ensure the stability of the liquid level in the upstream buffer tank.

[0041] Preferably, in step S5, during the operation of the vacuum system, in order to obtain a stable vacuum in the production unit, the downstream inlet control valve and the vacuum gauge of the production unit are interlocked. If a higher vacuum is required, the opening of the downstream inlet control valve is automatically increased; conversely, if a lower vacuum is required, the opening of the downstream inlet control valve is automatically decreased.

[0042] This invention provides an industrial continuous dehydration vacuum system and its operating method. It offers the following advantages:

[0043] 1. Compared with conventional water ring vacuum pumps, the vacuum level can reach 100 Pa (absolute pressure) because the post-stage vacuum pump uses a high-boiling-point liquid that is soluble in water as the working fluid, which is far superior to the 2000 Pa (absolute pressure) of water ring vacuum pumps.

[0044] 2. Compared with water jet vacuum pumps, it consumes less water and achieves superior vacuum. Water only needs to be added during the first run; no further additions are required. Furthermore, the vacuum level can reach 100 Pa (absolute pressure), far exceeding the 8000 Pa (absolute pressure) of water jet vacuum pumps.

[0045] 3. Compared with Roots water ring vacuum units, the equipment is simpler and easier to maintain. It also has no requirements on the water vapor content in the pumped gas and is more adaptable to fluctuations in water vapor content during the dehydration process, ensuring continuous operation.

[0046] 4. Compared with steam jet pumps, the amount of wastewater generated is smaller. Apart from uncondensed water vapor in the production unit, the main component is a small amount of evaporated high-boiling-point liquid.

[0047] 5. Compared with reciprocating vacuum pumps, it can meet various vacuum conditions, has fewer vulnerable parts and a lower failure rate. It also has no requirements on the water vapor content in the pumped gas and is more adaptable to fluctuations in water vapor content during the dehydration process, ensuring continuous operation. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the system structure of the present invention.

[0049] The components are as follows: 1. Post-stage inlet control valve; 2. Post-stage vacuum pump; 3. Post-stage vent valve; 4. Post-stage buffer tank; 5. Post-stage heat exchanger; 6. Post-stage supply valve; 7. Post-stage circulating pump; 8. Heating source inlet control valve; 9. Heating source return valve; 10. Post-stage thermometer; 11. Working fluid inlet control valve; 12. Post-stage level gauge; 13. Cryogenic water inlet valve; 14. Cryogenic water return valve; 15. Pre-stage inlet valve; 16. Pre-stage vacuum pump; 17. Pre-stage vent valve; 18. Pre-stage buffer tank; 19. Pre-stage heat exchanger; 20. Pre-stage supply valve; 21. Cooling water inlet valve; 22. Cooling water return valve; 23. Vent pipeline; 24. Sewage control valve; 25. Pre-stage level gauge; 26. Tap water inlet valve; 27. Production unit vacuum gauge. Detailed Implementation

[0050] The technical solutions in 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.

[0051] Please see the appendix Figure 1 This invention provides an industrial continuous dehydration vacuum system, including a front-stage vacuum circuit and a rear-stage vacuum circuit.

[0052] The pre-vacuum circuit includes: a pre-vacuum pump 16, a pre-buffer tank 18, a pre-heat exchanger 19, a venting pipeline 23, a pre-level gauge 25, and pipelines connecting the above equipment, as well as a pre-inlet valve 15, a pre-venting valve 17, a pre-supply valve 20, a cooling water inlet valve 21, a cooling water return valve 22, a drain control valve 24, and a tap water inlet valve 26.

[0053] Among them, the pre-stage inlet valve 15 is installed on the pipeline at the inlet of the pre-stage vacuum pump 16, the pre-stage exhaust valve 17 is installed on the pipeline between the pre-stage vacuum pump 16 and the pre-stage buffer tank 18, the pre-stage supply valve 20 is installed on the pipeline between the pre-stage vacuum pump 16 and the pre-stage heat exchanger 19, the cooling water inlet valve 21 is installed on the pipeline between the cooling water inlet pipe and the pre-stage heat exchanger 19, the cooling water return valve 22 is installed on the pipeline between the cooling water return pipe and the pre-stage heat exchanger 19, the drain control valve 24 is installed on the pipeline between the drain pipe and the pre-stage buffer tank 18, the tap water inlet valve 26 is installed on the pipeline between the tap water inlet pipe and the pre-stage buffer tank 18, and the vent pipe 23 is connected to the pre-stage buffer tank 18.

[0054] The downstream vacuum circuit includes: downstream vacuum pump 2, downstream buffer tank 4, downstream heat exchanger 5, downstream circulation pump 7, downstream thermometer 10, downstream level gauge 12, production unit vacuum gauge 27, as well as pipelines connecting the above equipment and downstream inlet control valve 1, downstream exhaust valve 3, downstream supply valve 6, heating source inlet control valve 8, heating source return valve 9, working fluid inlet control valve 11, cryogenic water inlet valve 13, and cryogenic water return valve 14.

[0055] Among them, the downstream inlet control valve 1 is installed on the pipeline between the production unit and the downstream vacuum pump 2; the downstream exhaust valve 3 is installed on the pipeline between the downstream vacuum pump 2 and the downstream buffer tank 4; the downstream supply valve 6 is installed on the pipeline between the downstream heat exchanger 5 and the downstream circulating pump 7; the heating source inlet control valve 8 is installed on the pipeline between the heating source inlet pipe and the downstream buffer tank 4; the heating source return valve 9 is installed on the pipeline between the heating source return pipe and the downstream buffer tank 4; the working fluid inlet control valve 11 is installed on the pipeline between the working fluid inlet pipe and the downstream buffer tank 4; the cryogenic water inlet valve 13 is installed on the pipeline between the cryogenic water inlet pipe and the downstream heat exchanger 5; and the cryogenic water return valve 14 is installed on the pipeline between the cryogenic water return pipe and the downstream heat exchanger 5.

[0056] Specifically, the downstream inlet control valve 1 refers to the automated control valve that connects the production device requiring vacuum to the downstream vacuum pump 2.

[0057] Specifically, the post-stage vacuum pump 2 refers to the liquid ring vacuum pump located between the post-stage inlet control valve 1 and the post-stage exhaust liquid valve 3.

[0058] Specifically, the post-stage exhaust valve 3 refers to the valve located between the post-stage vacuum pump 2 and the post-stage buffer tank 4.

[0059] Specifically, the downstream buffer tank 4 refers to the container located between the downstream vacuum pump 2 and the downstream heat exchanger 5.

[0060] Specifically, the downstream heat exchanger 5 refers to the heat exchange equipment located between the downstream buffer tank 4 and the downstream liquid supply valve 6.

[0061] Specifically, the downstream liquid supply valve 6 refers to the valve located between the downstream heat exchanger 5 and the downstream circulating pump 7.

[0062] Specifically, the downstream circulation pump 7 refers to the liquid transfer pump located between the downstream liquid supply valve 6 and the downstream vacuum pump 2.

[0063] Specifically, the heating source inlet control valve 8 refers to the automated control valve used for heating the liquid in the downstream buffer tank 4 and controlling the flow rate of the heating source to regulate the evaporation of water, and it is connected to the downstream buffer tank 4.

[0064] Specifically, the heating source return valve 9 refers to the heating source flow circuit valve used for heating the liquid in the downstream buffer tank 4 and adjusting the flow rate after water evaporation, and is connected to the downstream buffer tank 4.

[0065] Specifically, the downstream thermometer 10 refers to a metering instrument used to automatically detect the liquid temperature inside the downstream buffer tank 4, and is connected to the downstream buffer tank 4.

[0066] Specifically, the working fluid inlet control valve 11 refers to the automated control valve used to add working fluid into the downstream buffer tank 4.

[0067] Specifically, the downstream level gauge 12 refers to a metering instrument used to automatically detect the liquid level in the downstream buffer tank 4, and is connected to the downstream buffer tank 4.

[0068] Specifically, the low-temperature water inlet valve 13 is a valve used to regulate the low-temperature water inlet flow rate of the downstream heat exchanger 5, and is connected to the downstream heat exchanger 5.

[0069] Specifically, the low-temperature water return valve 14 is a valve used to regulate the low-temperature water return flow of the downstream heat exchanger 5, and is connected to the downstream heat exchanger 5.

[0070] Specifically, the pre-stage inlet valve 15 refers to the valve used to control the opening and closing of the pipeline between the downstream buffer tank 4 and the pre-stage vacuum pump 16.

[0071] Specifically, the foreground vacuum pump 16 refers to the liquid ring vacuum pump located between the foreground inlet valve 15 and the foreground exhaust valve 17.

[0072] Specifically, the pre-stage exhaust valve 17 refers to the valve located in the pipeline between the pre-stage vacuum pump 16 and the pre-stage buffer tank 18.

[0073] Specifically, the forestage buffer tank 18 refers to the vacuum container located between the forestage exhaust valve 17 and the forestage heat exchanger 19.

[0074] Specifically, the fore-stage heat exchanger 19 refers to the heat exchange equipment located between the fore-stage buffer tank 18 and the fore-stage liquid supply valve 20.

[0075] Specifically, the fore-stage liquid supply valve 20 refers to the valve located between the fore-stage heat exchanger 19 and the fore-stage vacuum pump 16.

[0076] Specifically, the cooling water inlet valve 21 is a valve used to regulate the cooling water inlet flow of the pre-heat exchanger 19, and is connected to the pre-heat exchanger 19.

[0077] Specifically, the cooling water return valve 22 is a valve used to regulate the cooling water return flow of the pre-heat exchanger 19, and is connected to the pre-heat exchanger 19.

[0078] Specifically, the vent pipe 23 refers to the pipe that discharges the gas in the pre-buffer tank 18, and is connected to the pre-buffer tank 18.

[0079] Specifically, the drain control valve 24 is an automated control valve that regulates the liquid level in the pre-buffer tank 18 and is connected to the pre-buffer tank 18.

[0080] Specifically, the fore-stage level gauge 25 refers to a metering instrument used to automatically detect the liquid level in the fore-stage buffer tank 18, and is connected to the fore-stage buffer tank 18.

[0081] Specifically, the tap water inlet valve 26 is a valve used to control the addition of tap water to the pre-buffer tank 18, and is connected to the pre-buffer tank 18.

[0082] Specifically, the vacuum gauge 27 for the production unit refers to a measuring instrument used to automatically detect the vacuum level of the production unit, which is connected to the production unit.

[0083] As a preferred embodiment of the present invention, both the forestage vacuum pump 16 and the poststage vacuum pump 2 are liquid ring vacuum pumps.

[0084] As a preferred embodiment of the present invention, the forestage vacuum pump 16 and the poststage vacuum pump 2 are used in series.

[0085] As a preferred embodiment of the present invention, a pre-stage heat exchanger 19 is provided between the pre-stage vacuum pump 16 and the pre-stage buffer tank 18.

[0086] As a preferred embodiment of the present invention, a downstream heat exchanger 5 is provided between the downstream vacuum pump 2 and the downstream buffer tank 4.

[0087] As a preferred embodiment of the present invention, the pre-buffer tank 18 is equipped with a pre-level level gauge 25, which is interlocked with the drain control valve 24 according to the set level.

[0088] As a preferred embodiment of the present invention, a vacuum gauge 27 for the production device and a downstream inlet control valve 1 are provided between the production device and the downstream vacuum pump 2. The vacuum gauge 27 for the production device and the downstream inlet control valve 1 are interlocked and controlled according to the set vacuum level.

[0089] As a preferred embodiment of the present invention, the downstream buffer tank 4 is equipped with a downstream thermometer 10, which is interlocked with the heating source inlet control valve 8 according to the set temperature.

[0090] As a preferred embodiment of the present invention, the downstream buffer tank 4 is equipped with a downstream level gauge 12, which is interlocked with the working fluid inlet control valve 11 according to the set level.

[0091] As a preferred embodiment of the present invention, the heating source refers to steam, heat transfer oil, or electric heating, preferably steam.

[0092] As a preferred embodiment of the present invention, the low-temperature water is cold water with a temperature lower than room temperature, or an aqueous solution of ethylene glycol, or salt water.

[0093] The working fluid mentioned in this invention refers to a high-boiling-point liquid that is soluble in water. Preferably, it is an alcohol with a boiling point exceeding 200°C at atmospheric pressure (101325 Pa).

[0094] The liquid ring vacuum pump described in this invention refers to a multi-bladed rotor eccentrically mounted inside a pump casing. When the rotor rotates, it throws liquid toward the pump casing and forms a liquid ring concentric with the pump casing. The liquid ring and the rotor blades together form a rotary variable displacement vacuum pump with periodically changing volume.

[0095] The higher vacuum level mentioned in this invention refers to a vacuum level that is closer to absolute vacuum (0 Pa) than the actual vacuum level. Conversely, the lower vacuum level mentioned in this invention refers to a vacuum level that is further away from absolute vacuum (0 Pa) than the actual vacuum level. For example, a vacuum level of 5 Pa is higher than a vacuum level of 10 Pa.

[0096] This invention also discloses a method for operating an industrial continuous dehydration vacuum system, comprising the following steps:

[0097] Step 1: Open the working fluid inlet control valve 11, add tripropylene glycol to the downstream buffer tank 4, and interlock the working fluid inlet control valve 11 with the downstream level gauge 12. At the same time, set the value of the downstream level gauge 12 to 50%.

[0098] Step 2: Open the heating source return valve 9, and set the heating source inlet control valve 8 and the downstream thermometer 10 to interlock. At the same time, set the interlock value of the downstream thermometer 10 to 120℃.

[0099] Step 3: Open the tap water inlet valve 26, add tap water to the pre-stage buffer tank 18, and when the pre-stage level gauge 25 shows 30%, close the tap water inlet valve 26; and set the drain control valve 24 and the pre-stage level gauge 25 to interlock, and set the value of the pre-stage level gauge 25 to 50%.

[0100] Step 4: Open the pre-stage inlet valve 15, pre-stage exhaust valve 17, pre-stage supply valve 20, cooling water inlet valve 21, and cooling water return valve 22 in sequence, and then start the pre-stage vacuum pump 16.

[0101] Step 5: Set the downstream inlet control valve 1 and the vacuum gauge 27 of the production unit to interlock, and set the interlock value of the vacuum gauge 27 of the production unit to 300pa.

[0102] Step 6: Open the downstream exhaust valve 3, the downstream supply valve 6, the cryogenic water inlet valve 13, and the cryogenic water return valve 14 in sequence, and then open the downstream circulation pump 7 and the downstream vacuum pump 2 in sequence.

[0103] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An industrial continuous dehydration vacuum system, characterized in that, Includes a pre-stage vacuum circuit and a post-stage vacuum circuit; The pre-vacuum circuit includes: The fore-stage vacuum pump (16) is used to create an initial vacuum, provide negative pressure for the subsequent buffer tank (4), and remove moisture and non-condensable gases from the subsequent buffer tank (4) in a timely manner. A pre-stage buffer tank (18) is connected to the outlet of a pre-stage vacuum pump (16) for stabilizing the pumped liquid and discharging non-condensable gases. The inlet of the pre-stage heat exchanger (19) is connected to the pre-stage buffer tank (18), and the outlet is connected to the pre-stage vacuum pump (16) to cool the hot liquid discharged by the pre-stage vacuum pump (16). The subsequent vacuum circuit includes: A post-stage vacuum pump (2) is used to further improve the vacuum level based on the pre-stage vacuum pump (16), and the inlet end of the post-stage vacuum pump (2) is connected to the production device. The downstream buffer tank (4) is connected to the outlet of the downstream vacuum pump (2) to stabilize the pumped liquid and discharge water and non-condensable gas. The downstream buffer tank (4) is connected to the inlet of the upstream vacuum pump (16). The downstream heat exchanger (5) has its inlet connected to the downstream buffer tank (4) and its outlet connected to the downstream vacuum pump (2), and is used to cool the hot liquid discharged by the downstream vacuum pump (2).

2. The industrial continuous dehydration vacuum system according to claim 1, characterized in that, The pre-buffer tank (18) is connected to a vent pipe (23) for discharging gas from the pre-buffer tank (18); the pre-buffer tank (18) is equipped with a drain control valve (24) and a pre-buffer level gauge (25), which are linked for control; the pre-buffer tank (18) is equipped with a tap water inlet, and a tap water inlet valve (26) is installed on the tap water inlet pipe.

3. The industrial continuous dehydration vacuum system according to claim 1, characterized in that, The pre-heat exchanger (19) is provided with a cooling water inlet and a cooling water outlet. A cooling water inlet valve (21) is provided on the cooling water inlet pipe, and a cooling water return valve (22) is provided on the cooling water outlet pipe.

4. The industrial continuous dehydration vacuum system according to claim 1, characterized in that, A pre-stage liquid supply valve (20) is provided on the pipeline connecting the pre-stage vacuum pump (16) and the pre-stage heat exchanger (19). A pre-stage exhaust valve (17) is provided on the pipeline connecting the pre-stage vacuum pump (16) and the pre-stage buffer tank (18). A pre-stage inlet valve (15) is provided on the pipeline connecting the pre-stage vacuum pump (16) and the post-stage buffer tank (4).

5. The industrial continuous dehydration vacuum system according to claim 1, characterized in that, The downstream buffer tank (4) is connected to a working fluid inlet. A working fluid inlet control valve (11) is installed on the working fluid inlet pipeline. A downstream level gauge (12) is installed on the downstream buffer tank (4). The working fluid inlet control valve (11) and the downstream level gauge (12) are linked for control. The downstream buffer tank (4) is equipped with a heating source pipeline. A downstream thermometer (10) is installed on the downstream buffer tank (4). A heating source inlet control valve (8) is installed at the inlet of the heating source pipeline of the downstream buffer tank (4). A heating source return valve (9) is installed at the outlet of the heating source pipeline of the downstream buffer tank (4). The heating source inlet control valve (8) and the downstream thermometer (10) are linked for control.

6. The industrial continuous dehydration vacuum system according to claim 1, characterized in that, The downstream heat exchanger (5) is provided with a low-temperature water inlet and a low-temperature water outlet. A low-temperature water inlet valve (13) is provided on the low-temperature water inlet pipe, and a low-temperature water return valve (14) is provided on the low-temperature water outlet pipe.

7. An industrial continuous dehydration vacuum system according to claim 1, characterized in that, A downstream inlet control valve (1) is provided on the pipeline connecting the downstream vacuum pump (2) and the production device. The production device is equipped with a vacuum gauge. The downstream inlet control valve (1) is linked to the vacuum gauge for control. A downstream exhaust valve (3) is provided on the pipeline connecting the downstream vacuum pump (2) and the downstream buffer tank (4).

8. An industrial continuous dehydration vacuum system according to claim 1, characterized in that, A downstream circulation pump (7) is provided between the downstream vacuum pump (2) and the downstream heat exchanger (5), and a downstream liquid supply valve (6) is provided on the pipeline connecting the downstream circulation pump (7) and the downstream heat exchanger (5).

9. A method of operating an industrial continuous dehydration vacuum system according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Open the working fluid inlet control valve (11), add working fluid to the downstream buffer tank (4), and set the working fluid inlet control valve (11) and the downstream buffer tank (4) level gauge to be linked control. At the same time, set the interlock value of the downstream level gauge (12) to automatically replenish the working fluid. S2. Open the heating source return valve (9) and set the heating source inlet control valve (8) and the downstream thermometer (10) to be linked for control. At the same time, set the interlock value of the downstream thermometer (10) to automatically control the temperature and remove the moisture in the downstream buffer tank (4). S3. Open the tap water inlet valve (26), add tap water to the front buffer tank (18), and set the drain control valve (24) and the front level gauge (25) to be linked control. At the same time, set the interlock value of the front level gauge (25) to automatically drain the sewage and ensure the stability of the liquid level in the front buffer tank (18). S4. Open the pre-stage inlet valve (15), pre-stage exhaust valve (17), pre-stage supply valve (20), cooling water inlet valve (21), and cooling water return valve (22) in sequence, and then start the pre-stage vacuum pump (16). S5. Set the downstream inlet control valve (1) and the vacuum gauge (27) of the production device to be linked for control, and set the interlock value of the vacuum gauge (27) of the production device to obtain a stable vacuum of the production device. S6. Open the downstream exhaust valve (3), downstream supply valve (6), cryogenic water inlet valve (13), and cryogenic water return valve (14) in sequence, and then open the downstream circulation pump (7) and downstream vacuum pump (2) in sequence.

10. The working method according to claim 9, characterized in that, The working fluid is a high-boiling-point liquid that is soluble in water; the heating source refers to heating via steam, heat transfer oil, or electricity.

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