CN217594244U

CN217594244U - Adsorber and empty purification system that adsorbs that divides

Info

Publication number: CN217594244U
Application number: CN202221571391.9U
Authority: CN
Inventors: 王鹏; 彭辉; 司莉粉; 李静静; 杨马强
Original assignee: Kaifeng Huanghe Air Separation Group Co ltd
Current assignee: Kaifeng Huanghe Air Separation Group Co ltd
Priority date: 2022-06-22
Filing date: 2022-06-22
Publication date: 2022-10-18
Anticipated expiration: 2032-06-22

Abstract

The utility model relates to an adsorber and empty purification system that adsorbs that divides, including a jar body, be provided with the outlet duct on jar body top, be provided with the intake pipe on jar body bottom, the outlet duct that is located jar internal side on be provided with the shrouding, be provided with down the shrouding in the internal chamber of jar of below of upper sealing plate, upper sealing plate inscription circle diameter and lower shrouding circumcircle diameter all reduce gradually along the direction of intake pipe to outlet duct, be provided with two at least annular filter screens and by upper sealing plate, lower shrouding and two adjacent annular filter screens enclose the inclosed filter chamber that closes and form between upper sealing plate and the lower shrouding, the top of filter chamber be provided with the filler inlet pipe, the top of filter chamber be provided with the filler discharging pipe. The low adsorber dead zone is reduced. The utility model relates to a rationally, convenient to use, extensive market prospect has.

Description

Adsorber and empty purification system that adsorbs that divides

Technical Field

The utility model relates to an empty processing equipment field that divides, concretely relates to adsorber and empty absorption purification system that divides.

Background

Molecular sieve adsorbers are effective in purifying air and have been widely used in air separation plants in recent years. The molecular sieve adsorber is used for removing moisture, carbon dioxide, acetylene and other hydrocarbons in the air so as to ensure the safe operation of the air separation plant. In the adsorption purification cycle, when the molecular sieve is saturated, the adsorption capacity is lost. At this time, the molecular sieve needs to be desorbed and regenerated, and the adsorbate is desorbed from the adsorbent to recover the adsorption capacity of the molecular sieve and ensure the reuse of the molecular sieve adsorber. In the temperature swing adsorption molecular sieve adsorption purification device, the molecular sieve is generally adsorbed at normal temperature and desorbed and regenerated at 200-320 ℃.

Most of the existing air separation purification systems utilize an adsorber to purify compressed air. The air separation adsorber generally adopts a vertical axial bed adsorber, a horizontal adsorber or a vertical radial bed adsorber. In the conventional vertical radial flow adsorber, the dead zone area of a catalyst is large, and the performance of the adsorber is not stable enough. The internal structure of the vertical adsorber is optimally designed and applied to an air separation adsorption purification system, so that the stability of the air separation purification system taking the vertical radial bed adsorber as a core device is improved.

Disclosure of Invention

The utility model provides a to prior art not enough, the utility model provides a can reduce empty purification system that adsorbs that divides in low adsorber blind spot for overcome defect among the prior art.

The utility model adopts the technical proposal that: the utility model provides an adsorber, is applied to empty purification system that adsorbs of dividing, includes a jar body, is provided with the outlet duct on jar body top, is provided with the intake pipe on jar body bottom, the outlet duct that is located jar internal side on be provided with the shrouding, be provided with down the shrouding in the jar body inner chamber of the below of going up the shrouding, go up shrouding inscription circle diameter and down the external circle diameter of shrouding and all reduce gradually along the direction of intake pipe to outlet duct, go up and be provided with two at least annular filter screens and by last shrouding, down shrouding and two inclosed filter chambers that adjacent annular filter screen encloses and close and form down between shrouding, the top of filter chamber be provided with the filler inlet pipe, the top of filter chamber be provided with the filler discharging pipe.

Preferably, the number of the filter cavities is two, the two filter cavities are of annular structures, an activated alumina layer is arranged in one of the filter cavities positioned on the outer side, and a molecular sieve layer is arranged in one of the filter cavities positioned on the inner side.

Preferably, the tank body between the air inlet pipe and the lower sealing plate is provided with an air deflector, the air deflector is of a bucket-shaped structure, the diameter of an outer circle of the air deflector is gradually increased along with the increase of the height of the air deflector, a connecting rod is arranged between the air deflector and the air inlet pipe, an air guide cone is arranged on the lower sealing plate, and the air guide cone is located on the inner side of the annular filter screen closest to the central axis of the tank body.

Preferably, be located and be provided with first strengthening rib on the annular filter screen that is closest to jar body axis, the quantity of first strengthening rib adopts a plurality of, and the annular filter screen that is located the most distant from jar body axis between two adjacent first strengthening ribs sets up the second strengthening rib, equally divide on first strengthening rib and the second strengthening rib and do not be provided with the third strengthening rib, and first strengthening rib and second strengthening rib all adopt annular structure, and the third strengthening rib adopts rod-like structure.

The utility model provides an empty purification system that adsorbs that divides, includes feed gas conveyer pipe, purification gas conveyer pipe, exhaust emission pipe and desorption gas conveyer pipe, still includes as above the adsorber, two the adsorber on intake pipe and feed gas conveyer pipe between equally divide do not be linked together through first conveyer pipe, two the adsorber on divide equally between outlet duct and the purification gas conveyer pipe do not be linked together through the second conveyer pipe, two the adsorber on divide equally between outlet duct and the desorption gas conveyer pipe do not be linked together through the third conveyer pipe, two the adsorber on intake pipe and the exhaust emission pipe between equally divide and do not be linked together through the fourth conveyer pipe, be provided with on the desorption gas conveyer pipe along being close to third conveyer pipe and having set gradually electric heater and compressor unit in the direction of keeping away from the third conveyer pipe.

Preferably, purify gas delivery pipe and exhaust emission pipe on equally divide and do not be provided with online chromatograph, be provided with temperature sensor on the desorption gas delivery pipe between third conveyer pipe and the electric heater, equally divide on first conveyer pipe, second conveyer pipe, third conveyer pipe and the fourth conveyer pipe and do not be provided with the stop valve.

Preferably, the two air outlet pipes on the adsorbers are communicated through a pressure balance pipe, the pressure balance pipe is provided with an adjusting valve, and the pressure balance pipes on two sides of the adjusting valve are respectively provided with a pressure sensor.

The utility model has the advantages that: at first, the utility model discloses a be provided with down the shrouding in the jar body inner chamber of the below of last shrouding, go up shrouding inscription circle diameter and down the external circle diameter of shrouding and all reduce gradually along the direction of intake pipe to outlet duct, go up and be provided with two at least annular filter screens and by last shrouding, lower shrouding and two inclosed annular filter screens enclose the inclosed filter chamber that closes and form down between the shrouding and the lower shrouding, reduced the adsorber blind spot.

Secondly, the utility model is arranged on a line chromatograph at a purified gas conveying pipe, so as to feed back the gas component parameters after the adsorption of the adsorber under the working state, and the gas component data is convenient for the worker to judge whether the switching of the adsorber under the standby state needs to be carried out or not; the exhaust gas discharge pipe is provided with a gas component parameter which is convenient for feeding back the gas component parameter released by the absorber in the desorption state, and the personnel can conveniently judge whether the desorption process is finished or not through the gas component parameter.

Finally, the utility model discloses be provided with temperature sensor on the desorption gas conveyer pipe between third conveyer pipe and the electric heater and be convenient for the feedback through the desorption gas temperature parameter after the electric heater heating, be convenient for the staff according to the parameter adjustment electric heater's of temperature sensor feedback power.

The utility model has the advantages of simple structure, convenient operation, design benefit has improved work efficiency greatly, has fine social and economic benefits, is the product of easily using widely.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a partially enlarged schematic view of detail a of fig. 1.

Fig. 3 is a schematic structural diagram of the present invention.

Detailed Description

Example 1: as shown in fig. 1-2, an adsorber is applied to empty absorption purification system that divides, including a jar body 1, be provided with outlet duct 2 on 1 top of jar body, be provided with intake pipe 3 on 1 bottom of jar body, be located and be provided with shrouding 4 on the outlet duct 2 of 1 inboard of jar body, be provided with down shrouding 5 in 1 inner chamber of the jar body of the below of last shrouding 4, go up shrouding 4 inscription circle diameter and down 5 circumscribed circle diameters of shrouding all reduce along intake pipe 3 to outlet duct 2's direction gradually, go up and be provided with two at least annular filter screens 6 between shrouding 4 and the lower shrouding 5 and by last shrouding 4, the inclosed rose chamber that closes and form down shrouding 5 and two adjacent annular filter screens 6, the top of rose chamber be provided with filler inlet pipe 7, the top of rose chamber be provided with filler discharging pipe 8. The annular filter screen 6 adopts an annular net structure. The outer end of the filler feeding pipe 7 and the outer end of the filler discharging pipe 8 are respectively provided with a connecting flange 33, a sealing cover 34 is arranged on the connecting flange 33, a sealing gasket 35 is arranged between the sealing cover 34 and the connecting flange 33, and the sealing cover 34 and the connecting flange 33 are fixed through bolts 36.

The filter cavity adopts one or two annular structure cavities, and when the number of the filter cavities is one, the filler in the filter cavity adopts a molecular sieve; when the number of the filter cavities is two, one filter cavity positioned at the outer side is filled with an active alumina layer 9 or a molecular sieve layer 10, and when one filter cavity positioned at the outer side is filled with the active alumina layer 9, one filter cavity positioned at the inner side is filled with the molecular sieve layer 10; when the outer filtering cavity is filled with the molecular sieve layer 10, the inner filtering cavity is filled with the active alumina layer 9.

Preferably, the outer one of the filter cavities is filled with an active alumina layer 9, and the inner one of the filter cavities is filled with a molecular sieve layer 10.

In addition, the number of the filter cavities in this embodiment may also be an even number, and the activated alumina layer 9 and the molecular sieve layer 10 are sequentially and alternately distributed in the inner cavity of the tank body 1 between the upper seal plate 4 and the lower seal plate 5 along the direction from the central axis of the tank body 1 to the central axis of the tank body 1. Intake pipe 3 and the jar body 1 between the shrouding 5 down be provided with aviation baffle 11, aviation baffle 11 adopt the bucket structure, the diameter of aviation baffle 11 circumcircle along with the increase of aviation baffle 11 height and grow gradually, be provided with connecting rod 12 between aviation baffle 11 and the intake pipe 3, be provided with air guide vertebra 13 on the shrouding 5 down, air guide vertebra 13 adopts circular cone structure, air guide vertebra 13 is located the inboard of the annular filter screen 6 that is closest to jar body 1 axis.

Every the quantity of the filler inlet pipe 7 and the filler outlet pipe 8 that the filter chamber communicates all adopt a plurality of, a plurality of filler inlet pipe 7 and a plurality of filler outlet pipe 8 all adopt the star configuration to distribute in the outside of 1 axis of jar body. The filling and emptying of the active alumina layer 9 and the molecular sieve layer 10 are convenient, and the volume of the cavity is reduced.

Known by the prior art, the active alumina filler that constitutes active alumina layer 9 adopts amorphous form, the molecular sieve filler that constitutes molecular sieve layer 10 adopts amorphous form or graininess usually, the structural strength of annular filter screen 6 is lower relatively in addition, in order to improve the structural strength of the annular filter screen 6 that is closest to jar body 1 axis and the structural strength of the annular filter screen 6 that is furthest from jar body 1 axis, this product utilization be in lie in be provided with first strengthening rib 14 on the annular filter screen 6 that is closest to jar body 1 axis, the quantity of first strengthening rib 14 adopts a plurality of, lie in between two adjacent first strengthening ribs 14 and set up second strengthening rib 15 on the annular filter screen 6 that is furthest from jar body 1 axis, equally divide on first strengthening rib 14 and the second strengthening rib 15 and do not be provided with third strengthening rib 16, first strengthening rib 14 and second strengthening rib 15 all adopt annular structure, third strengthening rib 16 adopts shaft-like structure. A first reinforcing rib 14 and a third reinforcing rib 16 are arranged on the annular filter screen 6 closest to the central axis of the tank body 1 and positioned on the inner side of the annular filter screen 6; a second reinforcing rib 15 and a third reinforcing rib 16 are arranged on the annular filter screen 6 which is farthest away from the central axis of the tank body 1 and positioned on the outer side of the annular filter screen 6; first through cavities are arranged between the first reinforcing ribs 14 and the corresponding third reinforcing ribs 16, and second through cavities are arranged between the second reinforcing ribs 15 and the corresponding third reinforcing ribs 16.

In the using method of the embodiment, as shown in fig. 1 to fig. 2, when the activated alumina layer 9 is filled, the sealing cover 34 on the corresponding filler feeding pipe 7 on the filter cavity corresponding to the activated alumina layer 9 is opened, and simultaneously the activated alumina filler is fed to the plurality of filler feeding pipes 7 communicated with the filter cavity corresponding to the activated alumina layer 9 until the activated alumina filler in the plurality of filler feeding pipes 7 is located at the preset height, and then the corresponding sealing washer 35, the sealing cover 34 and the bolt 36 are sequentially installed. When the molecular sieve layer 10 is filled, the sealing covers 34 on the corresponding filler feeding pipes 7 on the filter cavity corresponding to the molecular sieve layer 10 are opened, and the corresponding filler feeding pipes 7 are simultaneously filled with the molecular sieve filler to a preset height.

Through this embodiment, realized utilizing active alumina layer 9 to adsorb earlier the vapor component of the compressed air after the water cooling system cooling, then utilize the carbon dioxide component among the molecular sieve layer 10 absorption compressed air, because the vapor component who contains in the compressed air is higher relatively after the water cooling system cooling, utilize active alumina layer 9 to adsorb earlier and then adsorb again through molecular sieve layer 10 and reduced the absorption coincidence of molecular sieve 10, and for the adsorbent layer of prior art's columnar structure, active alumina layer 9 and the molecular sieve 10 of this product all adopt the loop configuration, and go up shrouding 4 inscribed circle diameter and 5 external circle diameters of shrouding down and all reduce along intake pipe 3 to the direction of outlet duct 2 gradually, the dead zone of adsorbent layer obviously reduces.

In addition, the bottom of a part of the cavity for loading the molecular sieve layer of the existing adsorber is generally horizontal, and because the bottom of the part of the cavity is in a horizontal state, when the adsorbent needs to be replaced, the adsorbent at the bottom is generally not easy to empty to form a barrier to influence the use of the newly replaced adsorbent. The last 4 inscription circle diameters of shrouding of this product and 5 circumscribed circle diameters of shrouding down all reduce along 3 to the direction of outlet duct 2 of intake pipe gradually, the loading and the uninstallation of the adsorbent of being convenient for more.

Example 2: as shown in fig. 1 to fig. 3, an empty space division of dividing of design on the basis of embodiment 1 adsorbs purification system, including feed gas conveyer pipe 17, purification gas conveyer pipe 18, exhaust emission pipe 19 and desorption gas conveyer pipe 20, still include two adsorbers as embodiment 1, two the adsorber on intake pipe 3 and feed gas conveyer pipe 17 between equally divide and be linked together through first conveyer pipe 21 respectively, two the adsorber on the outlet duct 2 and purify gas conveyer pipe 18 between equally divide and be linked together through second conveyer pipe 22 respectively, two the adsorber on equally divide between outlet duct 2 and the desorption gas conveyer pipe 20 and be linked together through third conveyer pipe 23 respectively, two the adsorber on intake pipe 3 and exhaust emission pipe 19 between equally divide and be linked together through fourth conveyer pipe 24 respectively, be provided with on the desorption gas conveyer pipe 20 along being close to third conveyer pipe 23 to keeping away from third conveyer pipe 23 on the direction and set gradually electric heater 25 and compressor unit 26.

The purified gas delivery pipe 18 and the waste gas discharge pipe 19 are respectively provided with an online chromatograph 27, and a temperature sensor 28 is arranged on the desorption gas delivery pipe 20 between the third delivery pipe 23 and the electric heater 25.

The first delivery pipe 21, the second delivery pipe 22, the third delivery pipe 23, and the fourth delivery pipe 24 are each provided with a shut-off valve 29. The two air outlet pipes 2 on the adsorbers are communicated through a pressure balance pipe 30, the pressure balance pipe 30 is provided with a regulating valve 31, and the pressure balance pipes 30 on the two sides of the regulating valve 31 are respectively provided with a pressure sensor 32. The number of the pressure sensors 32 is two.

The method of use of this example is as follows: compressed air cooled by the precooling system at the upstream is conveyed to a raw material gas conveying pipe 17, the compressed air is conveyed to the adsorbers in a working state, the compressed air is conveyed to the corresponding air inlet pipe 3 through the corresponding first conveying pipe 21 in the process, then passes through the air deflector 11, is deflected and then enters a gap between the inner wall of the tank body 1 and the annular filter screen 6 at the outermost side along the inner wall of the tank body 1, then sequentially passes through an activated alumina layer 9 to adsorb water vapor components and a molecular sieve layer 10 to absorb the water vapor components and carbon dioxide components, and then is conveyed to a purified gas conveying pipe 18 through an air outlet pipe 2 and a corresponding second conveying pipe 22 and then is conveyed to a downstream air separation rectification system, and in the process, the gas component indexes are fed back through an online chromatograph 27 on the purified gas conveying pipe 18.

After the gas component index fed back by the on-line chromatograph 27 reaches the range of the system switching required to be preset, firstly, the regulating valve 31 is opened until the numerical values fed back by the two pressure sensors 32 on the two sides of the regulating valve 31 are equal, and at the moment, the pressure in the adsorber in the standby state is equal to the pressure in the adsorber in the state to be switched; the control valve 31 is then closed, the shut-off valve 29 on the respective first feed line 21 and the shut-off valve 29 on the respective second feed line 22 of the adsorber in the belt change-over state are then closed, and the shut-off valve 29 on the respective first feed line 21 and the corresponding shut-off valve 29 on the second feed line 22 of the adsorber in the standby state are simultaneously opened to complete the system change-over.

The adsorber originally in the standby state is in the working state at this time, the adsorber originally in the to-be-switched state is in the to-be-desorbed state at present, then the electric heater 25, the compressor unit 26, the stop valve 29 on the third delivery pipe 23 corresponding to the adsorber in the to-be-desorbed state and the stop valve 29 on the corresponding fourth delivery pipe 24 are opened, the desorbed gas is pressurized by the compressor unit 26, then is heated by the electric heater 25, and then enters the inner cavity of the annular filter screen 6 at the innermost side through the third delivery pipe 23 and the gas outlet pipe 2 on the adsorber in the to-be-desorbed state after the temperature is fed back by the temperature sensor 28, after being guided by the air guide cone 13, the gas passes through the molecular sieve layer 10, the activated alumina layer 9 and a gap between the annular filter screen 6 on the outermost side and the tank body 1 in sequence, and then is conveyed to the exhaust gas discharge pipe 19 to be discharged to the atmosphere through the air inlet pipe 3 and the fourth delivery pipe 24 in sequence, gas components are continuously fed back through the online chromatograph 27 on the exhaust gas discharge pipe 19 in the period, when the parameters fed back by the online chromatograph 27 on the exhaust gas discharge pipe 19 reach a preset range, the desorption process is completed, the electric heater 25, the compressor unit 26, the stop valve 29 on the third delivery pipe 23 corresponding to the adsorber to be in the desorption state and the stop valve 29 on the corresponding fourth delivery pipe 24 are closed, and the adsorber to be in the desorption state is converted into the standby state again.

By comparing the embodiment 2 with the embodiment 1, the embodiment 2 provides an air separation adsorption purification system based on the embodiment 1, compared with the traditional air adsorption purification system, the product is communicated through the air outlet pipes 2 on the two adsorbers through the pressure balance pipe 30, the pressure balance pipe 30 is provided with the regulating valve 31, and the pressure balance pipes 30 on both sides of the regulating valve 31 are respectively provided with the pressure sensors 32. The number of the pressure sensors 32 is two, so that pressure fluctuation generated during system switching is reduced, and the air separation adsorption purification system provided by the embodiment is convenient for feeding back gas component parameters adsorbed by the adsorbers in the working state after the purified gas conveying pipe 18 is installed on the line chromatograph 27, and is convenient for providing the gas component parameters for workers to judge whether the switching of the adsorbers in the standby state is needed or not; the exhaust gas discharge pipe 19 is provided with a gas component parameter which is convenient for feeding back the gas component parameter released by the adsorber in the desorption state and is convenient for personnel to judge whether the desorption process is finished or not. Meanwhile, a temperature sensor 28 is arranged on the desorption gas delivery pipe 20 between the third delivery pipe 23 and the electric heater 25, so that the desorption gas temperature parameter heated by the electric heater 25 can be fed back conveniently, and a worker can adjust the power of the electric heater 25 according to the parameter fed back by the temperature sensor 28 conveniently.

The utility model discloses an adsorber and empty branch that satisfy in empty technological equipment field worker needs of dividing adsorbs purification system, make the utility model discloses extensive market prospect has.

Claims

1. The utility model provides an adsorber is applied to empty purification system that adsorbs that divides, includes a jar body (1), is provided with outlet duct (2) on jar body (1) top, is provided with intake pipe (3) on jar body (1) bottom, its characterized in that: lie in jar body (1) inboard outlet duct (2) on be provided with shrouding (4), be provided with down shrouding (5) in jar body (1) inner chamber of the below of going up shrouding (4), go up shrouding (4) inscription circle diameter and down shrouding (5) external circle diameter all reduce along intake pipe (3) to the direction of outlet duct (2) gradually, go up shrouding (4) and down be provided with between shrouding (5) two at least annular filter screen (6) and by last shrouding (4), shrouding (5) and two adjacent annular filter screen (6) enclose the inclosed filter chamber that forms down, the top of filter chamber be provided with filler inlet pipe (7), the top of filter chamber be provided with filler discharging pipe (8).

2. The adsorber of claim 1 wherein: the number of the filter cavities is two, the two filter cavities are of annular structures, an activated alumina layer (9) is arranged in one of the filter cavities positioned on the outer side, and a molecular sieve layer (10) is arranged in one of the filter cavities positioned on the inner side.

3. The adsorber of claim 1 wherein: the air inlet pipe (3) and the tank body (1) between the lower sealing plates (5) are provided with air deflectors (11), the air deflectors (11) are of a bucket-shaped structure, the diameter of the circumscribed circle of the air deflectors (11) is gradually increased along with the increase of the height of the air deflectors (11), connecting rods (12) are arranged between the air deflectors (11) and the air inlet pipe (3), air guide cones (13) are arranged on the lower sealing plates (5), and the air guide cones (13) are located on the inner sides of the annular filter screens (6) which are closest to the central axis of the tank body (1).

4. The adsorber of claim 1 wherein: be located closest to jar body (1) axis annular filter screen (6) on be provided with first strengthening rib (14), the quantity of first strengthening rib (14) adopts a plurality of, be located the annular filter screen (6) of keeping away from jar body (1) axis furthest between two adjacent first strengthening ribs (14) on set up second strengthening rib (15), equally divide on first strengthening rib (14) and second strengthening rib (15) and do not be provided with third strengthening rib (16), annular structure is all adopted in first strengthening rib (14) and second strengthening rib (15), rod-shaped structure is adopted in third strengthening rib (16).

5. The utility model provides an empty purification system that adsorbs that divides, includes feed gas conveyer pipe (17), purifies gas conveyer pipe (18), exhaust emission pipe (19) and desorption gas conveyer pipe (20), its characterized in that: the adsorber comprises an adsorber according to any one of claims 1 to 4, wherein the air inlet pipes (3) of the two adsorbers are respectively communicated with a feed gas conveying pipe (17) through first conveying pipes (21), the air outlet pipes (2) of the two adsorbers are respectively communicated with a purified gas conveying pipe (18) through second conveying pipes (22), the air outlet pipes (2) of the two adsorbers are respectively communicated with a desorbed gas conveying pipe (20) through third conveying pipes (23), the air inlet pipes (3) of the two adsorbers are respectively communicated with a waste gas discharging pipe (19) through fourth conveying pipes (24), and the desorbed gas conveying pipes (20) are sequentially provided with electric heaters (25) and compressor units (26) along the direction from being close to the third conveying pipes (23) to being far away from the third conveying pipes (23).

6. The air separation adsorption purification system according to claim 5, characterized in that: the device is characterized in that an online chromatograph (27) is respectively arranged on the purified gas delivery pipe (18) and the waste gas discharge pipe (19), a temperature sensor (28) is arranged on the desorption gas delivery pipe (20) between the third delivery pipe (23) and the electric heater (25), and stop valves (29) are respectively arranged on the first delivery pipe (21), the second delivery pipe (22), the third delivery pipe (23) and the fourth delivery pipe (24).

7. The air separation adsorption purification system according to claim 5, characterized in that: the two air outlet pipes (2) on the adsorbers are communicated through pressure balance pipes (30), the pressure balance pipes (30) are provided with regulating valves (31), and the pressure balance pipes (30) on two sides of each regulating valve (31) are respectively provided with a pressure sensor (32).