Rectifying tower vacuum pump stage changing device

Abstract

The utility model relates to the technical field of chemical separation equipment, in particular to a rectifying tower vacuum pump stage changing device which comprises a rectifying tower, a condensing system, a reboiling system and a stage changing vacuum system, and the condensing system is used for collecting gasified materials at the top of the rectifying tower and condensing the gasified materials into a liquid phase through a condenser. The reboiling system is used for collecting liquid at the bottom of the rectifying tower and heating the liquid to a boiling state through a reboiler. And the stage-changing vacuum system is used for providing vacuum states with different vacuum degrees for the rectifying tower. The method has the effect of adapting to different material characteristics and process conditions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical separation equipment, and in particular to a rectifying column vacuum pump switching device. BACKGROUND

[0002] In the chemical separation process, the rectifying column is a commonly used device. In order to improve the separation efficiency, vacuum technology is widely used in the rectification process. However, the current common vacuum pumps, such as water ring vacuum pumps, steam jet pumps, etc., have problems such as high energy consumption and poor stability. The existing rectifying column vacuum solution usually adopts a single vacuum pump system. Due to the changes in material characteristics and process conditions during long-term operation, performance degradation and energy consumption increase often occur. CONTENT OF THE UTILITY MODEL

[0003] In order to adapt to different material characteristics and process conditions, the present application provides a rectifying column vacuum pump switching device.

[0004] The rectifying column vacuum pump switching device provided by the present application adopts the following technical scheme:

[0005] A rectifying column vacuum pump switching device, comprising a rectifying column, the top of the rectifying column is provided with a gas phase outlet, the bottom of the rectifying column is provided with a liquid phase outlet, the sidewall of the rectifying column is provided with a first reflux port near the top, the sidewall of the rectifying column is provided with a second reflux port near the bottom, the sidewall of the rectifying column is provided with a raw material inlet near the center, the liquid phase outlet is connected with a tower kettle product pipe, and the tower kettle product pipe is provided with a tower kettle product valve; a condensing system, the condensing system is used for collecting the gasification of the top of the rectifying column, condensing the collected gasification into liquid phase, and sending part of the liquid phase back to the rectifying column through the first reflux port, and collecting the remaining part of the liquid phase as the tower top product; a reboiling system, the reboiling system is used for collecting the liquid state of the bottom of the rectifying column, heating the collected liquid state to boiling, and sending the high-temperature liquid state back to the rectifying column through the second reflux port; a switching vacuum system, the switching vacuum system is connected with the gas phase outlet and is used for providing different vacuum degrees of vacuum state to the rectifying column.

[0006] By using the above technical scheme, the reboiling system is used to heat at the bottom of the rectifying column, the raw material is vaporized after being heated at the bottom of the rectifying column and rises and is condensed by the condensing system, part of the condensed liquid phase is collected, and part of the condensed liquid phase is refluxed to the top of the rectifying column. The rising gasification and the refluxed liquid phase product form sufficient gas-liquid exchange, the low-boiling-point product is concentrated at the upper part of the tower, the temperature is lower, and the pressure is lower, and the high-boiling-point product is concentrated at the bottom of the tower, the temperature is higher, and the pressure is greater, so that the rectification separation is realized.

[0007] Optionally, the control device is further provided, and the high liquid level sensor and the low liquid level sensor are arranged on the side wall of the rectifying tower, and the control device is connected with the high liquid level sensor, the low liquid level sensor and the tower kettle product valve.

[0008] By using the above technical scheme, the liquid level of the tower kettle can be effectively monitored and automatically controlled, so that the liquid level is prevented from being too high or too low, and the stable operation of the rectification process is ensured.

[0009] Optionally, the condensing system comprises a condenser and a condensing circulating pump, the condenser has a condensing inlet, a condensing outlet, a cooling medium inlet and a cooling medium outlet, the condensing inlet of the condenser is connected with the gas phase outlet through a gas phase circulating outflow pipe, the condensing outlet of the condenser is connected with the first reflux port through a first circulating reflux pipe, the condensing circulating pump is arranged at the first circulating reflux pipe, a tower top product pipe is arranged downstream of the condensing circulating pump, and a tower top product valve is arranged on the tower top product pipe.

[0010] By using the above technical scheme, the gasification of the top of the rectifying tower can be effectively condensed, and part of the gasification is sent back to the rectifying tower, so that the separation efficiency is improved.

[0011] Optionally, a pressure sensor is arranged at the top of the rectifying tower, and the pressure sensor and the tower top product valve are connected with the control device.

[0012] By using the above technical scheme, the collection of the tower top product can be automatically controlled according to the pressure of the tower top, so that the quality and yield of the tower top product are ensured.

[0013] Optionally, the reboiling system comprises a reboiler and a reboiling circulating pump, the reboiler has a reboiling inlet, a reboiling outlet, a heat exchange medium inlet and a heat exchange medium outlet, the reboiling inlet of the reboiler is connected with the liquid phase outlet through a liquid phase circulating outflow pipe, the reboiling outlet of the reboiler is connected with the second reflux port through a second circulating reflux pipe, and the reboiling circulating pump is arranged at the liquid phase circulating outflow pipe.

[0014] By using the above technical scheme, the liquid at the bottom of the rectifying tower can be effectively heated and circulated, so that the separation efficiency is improved.

[0015] Optionally, a temperature sensor is arranged at the top of the rectifying tower, and the temperature sensor and the reboiling circulating pump are connected with the control device.

[0016] By using the above technical scheme, the working state of the reboiling system can be automatically controlled according to the temperature of the tower top, so that the stable operation of the rectification process is ensured.

[0017] Optionally, the step-change vacuum system comprises a first vacuum pump, a second vacuum pump, a first communication pipe and a second communication pipe, the gas phase outlet is provided with a vacuum generating pipe, the first vacuum pump and the second vacuum pump are sequentially arranged in the vacuum generating pipe along the flow direction of the gas, a first control valve and a second control valve are sequentially arranged between the first vacuum pump and the second vacuum pump along the flow direction of the gas, one end of the first communication pipe is connected with the upstream of the first vacuum pump, the other end is connected between the first control valve and the second control valve, the first communication pipe is provided with a first communication valve, one end of the second communication pipe is connected with the downstream of the second vacuum pump, the other end is connected between the first control valve and the second control valve, the second communication pipe is provided with a second communication valve, and the first vacuum pump, the second vacuum pump, the first control valve, the second control valve, the first communication valve and the second communication valve are signal connected with the control device.

[0018] By adopting the above technical scheme, different vacuum pumps can be switched for rectification operation, the first vacuum pump and the second vacuum pump can be different vacuum pumps, so as to be independently operated or jointly operated in series, so as to provide different vacuum degrees for the rectification tower, adapt to different process conditions and material characteristics, improve the separation efficiency and prolong the service life.

[0019] Optionally, the step-change vacuum system further comprises a tail gas treatment device, and the tail gas treatment device is arranged in the vacuum generating pipe and located downstream of the second vacuum pump.

[0020] By adopting the above technical scheme, the uncondensed gas in the tower extracted by the vacuum pump during operation can be effectively treated.

[0021] Optionally, the raw material inlet is provided with a raw material pipe, the raw material pipe is provided with a raw material valve, and the raw material valve is signal connected with the control device.

[0022] By adopting the above technical scheme, the entering of the raw material can be controlled, and stable operation of the rectification process can be ensured.

[0023] Optionally, the rectification tower is internally provided with a plurality of layers of trays.

[0024] By adopting the above technical scheme, the gas-liquid contact area is improved, and the separation efficiency is further improved.

[0025] In summary, the present application has at least one of the following beneficial technical effects:

[0026] 1. The step-change vacuum system adopted by the present application can provide different vacuum degrees for the rectification tower, so as to adapt to different process conditions and material characteristics, improve the separation efficiency, reduce the energy consumption and prolong the service life.

[0027] 2. The application realizes automatic control through the signal connection of the control device with each sensor and valve, reduces manual operation, improves operation stability, and reduces maintenance cost. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a structural schematic diagram of the rectifying tower vacuum pump grade changing device provided by the application.

[0029] The following table shows the meanings of the reference numerals in the drawings: 1 - rectifying tower; 101 - gas phase outlet; 102 - first reflux port; 103 - raw material inlet; 104 - second reflux port; 105 - liquid phase outlet; 106 - tray; 2 - raw material pipe; 201 - raw material valve; 3 - tower kettle product pipe; 301 - tower kettle product valve; 4 - condenser; 5 - gas phase circulation outlet pipe; 6 - first circulation reflux pipe; 601 - condensation circulation pump; 602 - tower top product pipe; 603 - tower top product valve; 7 - reboiler; 8 - liquid phase circulation outlet pipe; 801 - reboiling circulation pump; 9 - second circulation reflux pipe; 10 - vacuum generation pipe; 1001 - first vacuum pump; 1002 - first control valve; 1003 - second control valve; 1004 - second vacuum pump; 1005 - tail gas treatment device; 11 - first communication pipe; 1101 - first communication valve; 12 - second communication pipe; 1201 - second communication valve; 13 - high liquid level sensor; 14 - low liquid level sensor; 15 - pressure sensor; 16 - temperature sensor. DETAILED DESCRIPTION

[0030] The following will be described in detail in combination with the accompanying drawings. Figure 1 The application will be further described in detail.

[0031] The application discloses a rectifying tower vacuum pump grade changing device.

[0032] As shown in the drawings, the rectifying tower vacuum pump grade changing device comprises a rectifying tower 1, a condensation system, a reboiling system, and a grade changing vacuum system. Figure 1

[0033] As shown in the drawings, the rectifying tower vacuum pump grade changing device comprises a rectifying tower 1, a condensation system, a reboiling system, and a grade changing vacuum system. Figure 1 ​As shown, specifically, the distillation column 1 has a gas phase outlet 101 at the top for discharging vaporized material. A liquid phase outlet 105 is located at the bottom, connected to a bottom product pipe 3. A bottom product valve 301 is installed on the bottom product pipe 3 to discharge liquid as the bottom product. A first reflux port 102 is located near the top of the side wall to receive liquid returned from the condensation system; a second reflux port 104 is located near the bottom of the side wall to receive liquid returned from the reboiling system. A raw material inlet 103 is located near the center of the side wall, connected to a raw material pipe 2. A raw material valve 201 is installed on the raw material pipe 2 for adding the raw material to be separated. The distillation column 1 has several trays 106 inside, increasing the gas-liquid contact area and thus improving separation efficiency.

[0034] The condensation system collects the vapors at the top of distillation column 1 and condenses them into a liquid phase via condenser 4. The condensed liquid phase is returned to the first reflux port 102 of distillation column 1 via the first reflux pipe 6, while the remaining portion is collected as the top product. A condensation circulation pump 601 is located at the first reflux pipe 6 to provide circulation power.

[0035] like Figure 1 As shown, specifically, the condensation system includes a condenser 4 and a condensation circulation pump 601. The condenser 4 has a condensation inlet, a condensation outlet, a cooling medium inlet, and a cooling medium outlet. The cooling medium inlet and outlet are used to circulate and supply low-temperature cooling medium to the condenser 4. The condensation inlet of the condenser 4 is connected to the gas phase outlet 101 through a gas phase circulation outlet pipe 5, and the condensation outlet of the condenser 4 is connected to the first return port 102 through a first circulation return pipe 6. The condensation circulation pump 601 is located at the first circulation return pipe 6, and a top product pipe 602 is located downstream of the condensation circulation pump 601. A top product valve 603 is installed on the top product pipe 602.

[0036] The reboiling system is used to collect the liquid at the bottom of distillation column 1 and heat it to boiling point through reboiler 7. The high-temperature liquid is then returned to the second reflux port 104 of distillation column 1 through the second circulation reflux pipe 9. The reboiling circulation pump 801 is located at the liquid phase circulation outlet pipe 8 to provide power for the circulation of the liquid.

[0037] like Figure 1 As shown, specifically, the reboiling system includes a reboiler 7 and a reboiling circulation pump 801. The reboiler 7 has a reboiling inlet, a reboiling outlet, a heat exchange medium inlet, and a heat exchange medium outlet. The heat exchange medium inlet and outlet are used to circulate and supply high-temperature heat exchange medium to the reboiler 7. The reboiling inlet of the reboiler 7 is connected to the liquid phase outlet 105 through a liquid phase circulation outlet pipe 8, and the reboiling outlet of the reboiler 7 is connected to the second reflux port 104 through a second circulation reflux pipe 9. The reboiling circulation pump 801 is located at the liquid phase circulation outlet pipe 8.

[0038] The stage-changing vacuum system is connected with the gas phase outlet 101. The stage-changing vacuum system comprises a first vacuum pump 1001, a second vacuum pump 1004, and a plurality of control valves and communication valves. By opening and closing the control valves and communication valves, different vacuum pumps can be switched to work, thereby providing the rectifying tower 1 with vacuum states of different vacuum degrees. This design enables the device to adapt to different process conditions and material characteristics, improves the separation efficiency, and reduces energy consumption. Among them, the first vacuum pump 1001 and the second vacuum pump 1004 can be different vacuum pumps. For example, the first vacuum pump 1001 can be a water ring vacuum pump, and the second vacuum pump 1004 can be a steam jet pump, so as to fully utilize the advantages of the two types of vacuum pumps.

[0039] As shown in Figure 1 , specifically, the stage-changing vacuum system comprises the first vacuum pump 1001, the second vacuum pump 1004, a first communication pipe 11, a second communication pipe 12, and a tail gas treatment device 1005. The gas phase outlet 101 is provided with a vacuum generating pipe 10. The first vacuum pump 1001, the second vacuum pump 1004, and the tail gas treatment device 1005 are sequentially arranged in the vacuum generating pipe 10 along the flow direction of the gas. The first control valve 1002 and the second control valve 1003 are sequentially arranged between the first vacuum pump 1001 and the second vacuum pump 1004 along the flow direction of the gas. One end of the first communication pipe 11 is connected with the upstream of the first vacuum pump 1001, and the other end is connected with the space between the first control valve 1002 and the second control valve 1003. The first communication pipe 11 is provided with a first communication valve 1101. One end of the second communication pipe 12 is connected with the downstream of the second vacuum pump 1004, and the other end is connected with the space between the first control valve 1002 and the second control valve 1003. The second communication pipe 12 is provided with a second communication valve 1201.

[0040] In order to realize automatic control, the rectifying tower vacuum pump stage-changing device further comprises a control device.

[0041] As shown in Figure 1 , the rectifying tower 1 is provided with a high liquid level sensor 13 and a low liquid level sensor 14 at the sidewall. The high liquid level sensor 13, the low liquid level sensor 14, the raw material valve 201, and the tower kettle product valve 301 are simultaneously signal-connected with the control device. The high liquid level sensor 13 and the low liquid level sensor 14 work simultaneously to determine the liquid level height in the rectifying tower 1. By transmitting the detection signals to the control device, the control device can realize effective monitoring of the liquid level in the rectifying tower 1, and automatically control the opening of the raw material valve 201 to provide raw materials into the rectifying tower 1, or the opening of the tower kettle product valve 301 to discharge the tower kettle product from the rectifying tower 1, so as to prevent the liquid level from being too high or too low, and ensure the stable operation of the rectification process.

[0042] As shown in Figure 1As shown, the rectifying tower 1 is provided with a pressure sensor 15, and the pressure sensor 15 and the tower top product valve 603 are connected to the control device. The pressure sensor 15 can determine the pressure at the top of the rectifying tower 1. When the pressure at the top is low, it proves that the vacuum degree at the top is high, so that the separation precision is high, and the purity of the gasification product at the top is higher. The collection of the gasification product at the high vacuum degree at the top can ensure the quality of the tower top product.

[0043] As shown in the figure, Figure 1 The rectifying tower 1 is provided with a temperature sensor 16, and the temperature sensor 16 and the reboiling circulating pump 801 are connected to the control device. The temperature sensor 16 can determine the temperature at the top of the rectifying tower 1. The vacuum can reduce the boiling point of different components in the raw material. By controlling the reboiling circulating pump 801 to heat the liquid at the bottom of the tower, and using the high-temperature gasification product after heating and gasification, the temperature at the top of the tower can be maintained at the boiling point of the component with the lowest boiling point, so as to improve the purity of the gasification product at the top of the tower.

[0044] As shown in the figure, Figure 1 The first vacuum pump 1001, the second vacuum pump 1004, the first control valve 1002, the second control valve 1003, the first communication valve 1101 and the second communication valve 1201 are connected to the control device. The control device can detect the temperature and pressure in the rectifying tower 1 in real time, and determine whether the vacuum pump needs to be switched according to the temperature, pressure, process conditions and material characteristics. When the first vacuum pump 1001 needs to work, the control device controls the first control valve 1002 and the second communication valve 1201 to open, and the second control valve 1003 and the first communication valve 1101 to close. When the communication valve and the control valve are in the corresponding on-off state, the control device controls the first vacuum pump 1001 to start. When the second vacuum pump 1004 needs to work, the control device controls the second control valve 1003 and the first communication valve 1101 to open, and the first control valve 1002 and the second communication valve 1201 to close. When the communication valve and the control valve are in the corresponding on-off state, the control device controls the second vacuum pump 1004 to start. When the first vacuum pump 1001 and the second vacuum pump 1004 need to work together, the control device controls the first control valve 1002 and the second control valve 1003 to open, and the first communication valve 1101 and the second communication valve 1201 to close. When the communication valve and the control valve are in the corresponding on-off state, the control device controls the first vacuum pump 1001 and the second vacuum pump 1004 to start.

[0045] The above are preferred embodiments of the present application, which do not limit the protection scope of the present application. Therefore, any equivalent changes made on the basis of the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A vacuum pump changeover device for a rectification column, characterized by, The application relates to a distillation tower (1) and a condensing system, a reboiling system and a stage-changing vacuum system. The distillation tower (1) is provided with a gas phase outlet (101) at the top, a liquid phase outlet (105) at the bottom, a first reflux port (102) at the side wall near the top, a second reflux port (104) at the side wall near the bottom, and a raw material inlet (103) at the side wall near the center; the liquid phase outlet (105) is connected with a tower kettle product pipe (3) which is provided with a tower kettle product valve (301). The condensing system is used for collecting the vaporized material at the top of the distillation tower (1), condensing the collected vaporized material into liquid phase, sending part of the liquid phase back to the distillation tower (1) through the first reflux port (102), and collecting the remaining part of the liquid phase as tower top product. The reboiling system is used for collecting the liquid material at the bottom of the distillation tower (1), heating the collected liquid material to boiling, and sending the high-temperature liquid material back to the distillation tower (1) through the second reflux port (104). The stage-changing vacuum system is connected with the gas phase outlet (101) and used for providing different vacuum degrees to the distillation tower (1).

2. The rectifier vacuum pump exchanger of claim 1, wherein, The control device is connected with the high liquid level sensor (13), the low liquid level sensor (14) and the tower kettle product valve (301).

3. The rectifier vacuum pump exchanger of claim 2, wherein, The condensing system comprises a condenser (4) and a condensing circulating pump (601); the condenser (4) is provided with a condensing inlet, a condensing outlet, a cooling medium inlet and a cooling medium outlet; the condensing inlet of the condenser (4) is connected with the gas phase outlet (101) through a gas phase circulating outflow pipe (5); the condensing outlet of the condenser (4) is connected with the first reflux port (102) through a first circulating reflux pipe (6); the condensing circulating pump (601) is arranged at the first circulating reflux pipe (6); a tower top product pipe (602) is arranged downstream of the condensing circulating pump (601); and a tower top product valve (603) is arranged on the tower top product pipe (602).

4. The rectifier vacuum pump exchanger of claim 3, wherein, The distillation tower (1) is provided with a pressure sensor (15) at the top; the pressure sensor (15) and the tower top product valve (603) are connected with the control device.

5. The rectifier vacuum pump exchanger of claim 2, wherein, The reboiling system comprises a reboiler (7) and a reboiling circulating pump (801); the reboiler (7) is provided with a reboiling inlet, a reboiling outlet, a heat exchange medium inlet and a heat exchange medium outlet; the reboiling inlet of the reboiler (7) is connected with the liquid phase outlet (105) through a liquid phase circulating outflow pipe (8); the reboiling outlet of the reboiler (7) is connected with the second reflux port (104) through a second circulating reflux pipe (9); and the reboiling circulating pump (801) is arranged at the liquid phase circulating outflow pipe (8).

6. The rectifier vacuum pump exchanger of claim 5, wherein, The rectification tower (1) is provided with a temperature sensor (16) at the top, and the temperature sensor (16) and the reboiling circulating pump (801) are both signal connected with the control device.

7. The rectifier vacuum pump exchanger of claim 2, wherein, The stage-changing vacuum system comprises a first vacuum pump (1001), a second vacuum pump (1004), a first communication pipe (11) and a second communication pipe (12), the gas phase outlet (101) is provided with a vacuum generating pipe (10), the first vacuum pump (1001) and the second vacuum pump (1004) are sequentially arranged in the vacuum generating pipe (10) along the flow direction of the gas, a first control valve (1002) and a second control valve (1003) are sequentially arranged between the first vacuum pump (1001) and the second vacuum pump (1004) along the flow direction of the gas, one end of the first communication pipe (11) is connected with the upstream of the first vacuum pump (1001), the other end is connected between the first control valve (1002) and the second control valve (1003), the first communication pipe (11) is provided with a first communication valve (1101), one end of the second communication pipe (12) is connected with the downstream of the second vacuum pump (1004), the other end is connected between the first control valve (1002) and the second control valve (1003), the second communication pipe (12) is provided with a second communication valve (1201), and the first vacuum pump (1001), the second vacuum pump (1004), the first control valve (1002), the second control valve (1003), the first communication valve (1101) and the second communication valve (1201) are all signal connected with the control device.

8. The rectifier vacuum pump exchanger of claim 7, wherein, The stage-changing vacuum system further comprises a tail gas treatment device (1005), which is arranged in the vacuum generating pipe (10) and located downstream of the second vacuum pump (1004).

9. The rectifier vacuum pump exchanger of claim 2, wherein, The raw material inlet (103) is provided with a raw material pipe (2), the raw material pipe (2) is provided with a raw material valve (201), and the raw material valve (201) is signal connected with the control device.

10. The rectifier vacuum pump exchanger of claim 1, wherein, The rectification tower (1) is internally provided with a plurality of layers of tower plates (106). The rectification tower (1) is internally provided with a plurality of layers of tower plates (106).

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