CN210951349U

CN210951349U - Activated carbon adsorption catalytic combustion equipment

Info

Publication number: CN210951349U
Application number: CN201921468316.8U
Authority: CN
Inventors: 王小兵
Original assignee: Shandong Hanyuan Environmental Protection Technology Co ltd
Current assignee: Shandong Hanyuan Environmental Protection Technology Co ltd
Priority date: 2019-09-04
Filing date: 2019-09-04
Publication date: 2020-07-07
Anticipated expiration: 2029-09-04

Abstract

The utility model relates to the technical field of waste gas treatment accessories, in particular to an activated carbon adsorption catalytic combustion device which can desorb activated carbon adsorbents without stopping the device, thereby ensuring the whole working process and improving the practicability; the service life of the activated carbon adsorbent can be effectively prolonged, the treatment effect on waste gas can be effectively improved, and the use reliability can be improved; including adsorption tank, catalytic combustion device, desorption fan, tonifying cold fan, rose box, four group's pillars, three first ventilation pipes of group and two sets of baffles, be provided with the working chamber in the adsorption tank, two sets of baffles separate into three absorption cavities with the working chamber to all be provided with the active carbon adsorbent in three absorption cavities of group, still include second intercommunication tuber pipe, exhaust fan, air inlet pipeline, first blast valve, third intercommunication tuber pipe, second blast valve, fourth intercommunication tuber pipe, third blast valve, baffle and glass fiber filter equipment.

Description

Activated carbon adsorption catalytic combustion equipment

Technical Field

The utility model relates to a technical field of exhaust-gas treatment auxiliary device especially relates to an active carbon adsorption catalytic combustion equipment.

Background

As is well known, an activated carbon adsorption catalytic combustion apparatus is an auxiliary device for treating exhaust gas by means of activated carbon adsorption and catalytic combustion to improve environmental protection, and is widely used in the fields of industrial production and environmental protection; the existing activated carbon adsorption catalytic combustion equipment comprises an adsorption box, a catalytic combustion device, a desorption fan and an air supplement cooler, wherein a working cavity is arranged in the adsorption box, an activated carbon adsorbent is arranged in the working cavity, an air inlet pipeline is arranged at one end of the adsorption box, an exhaust pipeline and a desorption pipeline are arranged at the top end of the adsorption box, an exhaust fan is arranged at the exhaust pipeline, the input end of the air supplement cooler is communicated with the output end of the desorption pipeline, the output end of the air supplement cooler is communicated with the input end of the catalytic combustion device, the input end of the desorption fan is communicated with the output end of the catalytic combustion device, and the output end of the desorption fan is communicated with the adsorption box; when the existing activated carbon adsorption catalytic combustion equipment is used, waste gas enters a working cavity through an air inlet pipeline, impurities in the waste gas are adsorbed through an activated carbon adsorbent, purified gas is discharged from an exhaust pipeline, when the impurities adsorbed by the activated carbon are more, an exhaust fan is turned off, hot gas generated by combustion of a catalytic combustion device is blown into the working cavity through a desorption fan to desorb the activated carbon adsorbent, and the desorbed impurities are pumped into the catalytic combustion device by a supplementary cooling fan to be combusted; the existing activated carbon adsorption catalytic combustion equipment is found to be low in practicability because the equipment needs to be shut down when desorbing an activated carbon adsorbent, so that the whole working process is influenced; and the waste gas is treated by the activated carbon adsorbent, the treatment load of the activated carbon adsorbent is large, the service life of the activated carbon is influenced, the treatment effect of the waste gas is influenced, and the use reliability is low.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides a desorption treatment of the activated carbon adsorbent without shutdown, which ensures the whole working process and improves the practicability; and the service life of the activated carbon adsorbent can be effectively prolonged, the waste gas treatment effect can be effectively improved, and the use reliability of the activated carbon adsorption catalytic combustion equipment can be improved.

The utility model discloses an activated carbon adsorption catalytic combustion device, which comprises an adsorption box, a catalytic combustion device, a desorption fan and a supplemental cooling fan, wherein a working cavity is arranged inside the adsorption box; the bottom ends of the four groups of struts are respectively connected with the left front side, the right front side, the left rear side and the right rear side of the top end of the filter box, the top ends of the four groups of struts are respectively connected with the left front side, the right front side, the left rear side and the right rear side of the bottom end of the adsorption box, two groups of clapboards are arranged inside the working cavity, the working cavity is divided into three groups of adsorption cavities by the two groups of clapboards, activated carbon adsorption bodies are arranged in the three groups of adsorption cavities, a second communicated air pipe is arranged at the top end of the adsorption box, the second communicated air pipe is communicated with the three groups of adsorption cavities, an exhaust fan is arranged at the output end of the second communicated air pipe, a placing cavity is arranged inside the filter box, an air inlet pipeline is arranged at the left end of the filter box in a communicated manner, and the bottom ends of the three groups of first communicated air pipes extend into the placing cavity from the top end, the top ends of the three groups of first connecting ventilation pipes respectively extend into the three groups of adsorption cavities from the bottom ends of the adsorption boxes, first air valves are arranged on the three groups of first connecting ventilation pipes, three groups of third communicating air pipes are arranged at the top ends of the adsorption boxes, the three groups of third communicating air pipes are respectively communicated with the three groups of adsorption cavities, second air valves are arranged on the three groups of third communicating air pipes, the output ends of the three groups of third communicating air pipes are communicated with the output end of the air supplementing fan, the output end of the air supplementing fan is communicated with the input end of the catalytic combustion device, three groups of fourth communicating air pipes are communicated with the bottom end of the adsorption box, the bottom ends of the three groups of fourth communicating air pipes are communicated with the output end of the desorption fan, the input end of the desorption fan is communicated with the output end of the catalytic combustion device, and the three groups of fourth communicating air pipes are; the top of placing the chamber is vertical to be provided with two sets of baffles, two sets of baffles will place the top in chamber and separate into three group and filter the cavity to all be provided with glass fiber filter equipment in three group filter the cavity, the bottom of three first ventilation pipes of group communicates with each other with three group filter the cavity respectively.

The utility model discloses an active carbon adsorption catalytic combustion equipment, glass fiber filter equipment includes outline and interior frame, and the inside of outline is provided with multilayer glass fiber and hinders the lacquer net, and the bottom of outline is provided with the supporting network, and glass fiber hinders the bottom of lacquer net and pastes tightly with the top of supporting network, interior frame is located the inside of outline and is located multiunit glass fiber and hinders the top of lacquer net, and the bottom of interior frame is provided with presses the net, the bottom that presses the net and multilayer glass fiber hinder the top of lacquer net and paste tightly, connect through the hasp between interior frame and the outline.

The utility model discloses an active carbon adsorption catalytic combustion equipment, the front end of rose box is provided with three maintenance mouths of group, three maintenance mouths of group communicate with each other with three group's filtration cavities respectively to three maintenance mouths of group are respectively just to three glass fiber filter equipment of group, and go out at three maintenance mouths of group and all are provided with the switch door.

The utility model discloses an active carbon adsorption catalytic combustion equipment, multilayer glass fiber hinders the density from the lower and become dense gradually of lacquer net.

The utility model discloses an active carbon adsorption catalytic combustion equipment, be provided with left branch brace bar and right branch brace bar on the left side wall and the right side wall of filtration cavity respectively, the left side and the right side of outline bottom contact with the top of left branch brace bar and right branch brace bar respectively, and the top of left branch brace bar and right branch brace bar all is provided with multiunit semicircle positioning groove, the bottom of outline is provided with multiunit semicircle reference column, multiunit semicircle reference column is located multiunit semicircle positioning groove respectively.

The utility model discloses an active carbon adsorption catalytic combustion equipment still includes fifth intercommunication tuber pipe, the one end of fifth intercommunication tuber pipe and the input intercommunication of benefit air-cooler, the other end and the first ventilation pipe intercommunication of fifth intercommunication tuber pipe to be provided with the fourth blast gate on fifth intercommunication tuber pipe.

The utility model discloses an active carbon adsorption catalytic combustion equipment, exhaust fan's output is provided with the emission chimney.

The utility model discloses an active carbon adsorption catalytic combustion equipment, the front end bottom of rose box is provided with three groups and collects the drawer, three groups are collected the drawer and are located three groups glass fiber filter equipment respectively under.

Compared with the prior art, the beneficial effects of the utility model are that: waste gas enters the placing cavity through the air inlet pipeline, the glass fiber filtering device is used for primarily filtering the waste gas to filter out larger dust and a part of paint mist in the waste gas, then the waste gas enters the working cavity through the first connecting ventilation pipe, and the waste gas is treated through the activated carbon adsorbent, so that the treatment load of the activated carbon adsorbent is reduced, the service life of the activated carbon adsorbent is effectively prolonged, the treatment effect of the waste gas is improved, and the use reliability is improved; when needing to carry out desorption to the active carbon adsorption body, close this active carbon adsorption body place and adsorb the first blast valve on the first ventilation pipe of cavity intercommunication, waste gas no longer gets into this absorption cavity, open third blast valve and the second blast valve that this group adsorbs the cavity intercommunication, the high-temperature gas that catalytic combustion device burning produced gets into the absorption cavity through fourth intercommunication tuber pipe and carries out desorption to the active carbon adsorption body, the impurity that the desorption got off gets into catalytic combustion device through third intercommunication tuber pipe and burns, generate vapor and carbon dioxide, need not the shut down and can carry out desorption to the active carbon adsorption body and handle, guarantee the process of whole work, and the high practicality is improved.

Drawings

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

FIG. 2 is a schematic structural view of the filtering box of the present invention;

fig. 3 is a schematic view of a part of an enlarged structure at a in fig. 2 according to the present invention;

FIG. 4 is a perspective view of the left support bar of the present invention;

in the drawings, the reference numbers: 1. an adsorption tank; 2. a catalytic combustion device; 3. a desorption fan; 4. supplementing a cold air blower; 5. a filter box; 6. a pillar; 7. a first connecting ventilation pipe; 8. a partition plate; 9. an activated carbon adsorbent; 10. a second communicating air pipe; 11. an exhaust fan; 12. an air inlet pipeline; 13. a third communicating air pipe; 14. a second air valve; 15. a fourth communicating air pipe; 16. a third air valve; 17. a baffle plate; 18. a glass fiber filter device; 19. an outer frame; 20. an inner frame; 21. a glass fiber paint barrier web; 22. a support net; 23. pressing the net; 24. opening and closing the door; 25. a left support bar; 26. a semicircular positioning groove; 27. a semicircular positioning column; 28. a fifth communicating air pipe; 29. a fourth air valve; 30. discharging a chimney; 31. a collection drawer; 32. a first air valve.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

As shown in fig. 1 to 4, the activated carbon adsorption catalytic combustion apparatus of the present invention includes an adsorption tank 1, a catalytic combustion device 2, a desorption fan 3, and a cooling air supplement fan 4, wherein a working chamber is disposed inside the adsorption tank 1; the device also comprises a filter box 5, four groups of struts 6 and three groups of first connecting ventilation pipes 7, wherein the bottom ends of the four groups of struts 6 are respectively connected with the left front side, the right front side, the left rear side and the right rear side of the top end of the filter box 5, the top ends of the four groups of struts 6 are respectively connected with the left front side, the right front side, the left rear side and the right rear side of the bottom end of the adsorption box 1, two groups of partition plates 8 are arranged inside the working cavity, the working cavity is divided into three groups of adsorption cavities by the two groups of partition plates 8, active carbon adsorption bodies 9 are respectively arranged in the three groups of adsorption cavities, a second connecting ventilation pipe 10 is arranged at the top end of the adsorption box 1, the second connecting ventilation pipe 10 is communicated with the three groups of adsorption cavities, an exhaust fan 11 is arranged at the output end of the second connecting ventilation pipe 10, a placing cavity is arranged inside the filter box 5, an air inlet pipeline 12 is communicated with the left end of the filter box 5, the top ends of the three groups of first connecting and ventilating pipes 7 respectively extend into the three groups of adsorption chambers from the bottom end of the adsorption box 1, the three groups of first connecting ventilation pipes 7 are all provided with first air valves 32, the top end of the adsorption box 1 is provided with three groups of third connecting air pipes 13, the three groups of third connecting air pipes 13 are respectively communicated with the three groups of adsorption chambers, the three groups of third communicating air pipes 13 are provided with second air valves 14, the output ends of the three groups of third communicating air pipes 13 are communicated with the output end of the air supplementing fan 4, the output end of the air supplementing fan 4 is communicated with the input end of the catalytic combustion device 2, the bottom end of the adsorption box 1 is provided with three groups of fourth communicating air pipes 15 in a communicating manner, the bottom ends of the three groups of fourth communicating air pipes 15 are communicated with the output end of the desorption fan 3, the input end of the desorption fan 3 is communicated with the output end of the catalytic combustion device 2, and the three groups of fourth communicating air pipes 15 are provided with third air valves 16; two groups of baffles 17 are vertically arranged at the top of the placing cavity, the two groups of baffles 17 divide the top of the placing cavity into three groups of filtering cavities, glass fiber filtering devices 18 are arranged in the three groups of filtering cavities, and the bottom ends of the three groups of first connecting and ventilating pipes 7 are respectively communicated with the three groups of filtering cavities; waste gas enters the placing cavity through the air inlet pipeline, the glass fiber filtering device is used for primarily filtering the waste gas to filter out larger dust and a part of paint mist in the waste gas, then the waste gas enters the working cavity through the first connecting ventilation pipe, and the waste gas is treated through the activated carbon adsorbent, so that the treatment load of the activated carbon adsorbent is reduced, the service life of the activated carbon adsorbent is effectively prolonged, the treatment effect of the waste gas is improved, and the use reliability is improved; when needing to carry out desorption to the active carbon adsorption body, close this active carbon adsorption body place and adsorb the first blast valve on the first ventilation pipe of cavity intercommunication, waste gas no longer gets into this absorption cavity, open third blast valve and the second blast valve that this group adsorbs the cavity intercommunication, the high-temperature gas that catalytic combustion device burning produced gets into the absorption cavity through fourth intercommunication tuber pipe and carries out desorption to the active carbon adsorption body, the impurity that the desorption got off gets into catalytic combustion device through third intercommunication tuber pipe and burns, generate vapor and carbon dioxide, need not the shut down and can carry out desorption to the active carbon adsorption body and handle, guarantee the process of whole work, and the high practicality is improved.

The utility model discloses an active carbon adsorption catalytic combustion equipment, glass fiber filter equipment 18 includes outline 19 and interior frame 20, the inside of outline 19 is provided with multilayer glass fiber and hinders lacquer net 21, the bottom of outline 19 is provided with supporting net 22, glass fiber hinders the bottom of lacquer net 21 and supports the top of net 22 and pastes tightly, interior frame 20 is located the inside of outline 19 and is located the top that multiunit glass fiber hinders lacquer net 21, the bottom of interior frame 20 is provided with pressing net 23, the bottom of pressing net 23 and multilayer glass fiber hinder the top of lacquer net 21 and paste tightly, connect through the hasp between interior frame 20 and the outline 19; the glass fiber paint resisting net is clamped tightly through the supporting net and the pressing net, the glass fiber paint resisting net is convenient to disassemble and assemble, and the use reliability is improved.

The utility model discloses an active carbon adsorption catalytic combustion equipment, the front end of rose box 5 is provided with three groups of service ports, three groups of service ports are respectively communicated with three groups of filtering cavities, and three groups of service ports are respectively over against three groups of glass fiber filtering devices 18, and the three groups of service ports are all provided with switch doors 24; the glass fiber filtering device is convenient to replace through the maintenance port.

In the activated carbon adsorption catalytic combustion equipment, the density of the multilayer glass fiber paint resisting net 21 becomes denser gradually from bottom to top; the filtering effect on the paint mist is ensured.

The utility model discloses an active carbon adsorption catalytic combustion equipment, be provided with left support bar 25 and right support bar on the left side wall and the right side wall of filtration cavity respectively, the left side and the right side of 19 bottoms of outline frames contact with the top of left support bar 25 and right support bar respectively, the top of left support bar 25 and right support bar all is provided with multiunit semicircle positioning groove 26, the bottom of outline frames 19 is provided with multiunit semicircle positioning column 27, multiunit semicircle positioning column 27 is located multiunit semicircle positioning groove 26 respectively; support the outer frame through left branch brace and right branch brace to fix a position the outer frame through the cooperation of multiunit semicircle constant head tank and multiunit semicircle reference column.

The utility model discloses an active carbon adsorption catalytic combustion equipment still includes fifth intercommunication tuber pipe 28, and one end and the input of tonifying cold wind machine 4 of fifth intercommunication tuber pipe 28 communicate, and the other end and the first ventilation pipe 7 of fifth intercommunication tuber pipe 28 communicate to be provided with fourth blast gate 29 on fifth intercommunication tuber pipe 28; after catalytic combustion, opening a fourth air valve, and discharging waste gas generated by combustion into a second communicating air pipe through a fifth communicating air pipe.

The utility model discloses an active carbon adsorption catalytic combustion equipment, exhaust fan 11's output is provided with discharges chimney 30.

In the activated carbon adsorption catalytic combustion equipment of the utility model, three groups of collection drawers 31 are arranged at the bottom of the front end of the filter box 5, and the three groups of collection drawers 31 are respectively positioned under three groups of glass fiber filtering devices 18; the paint mist filtered by the glass fiber filtering device can be collected through the collecting drawer and then uniformly treated.

The utility model discloses an active carbon adsorption catalytic combustion equipment, it is at the during operation, and waste gas gets into through the air-supply line and places the intracavity, carries out prefilter to waste gas through glass fiber filter equipment, filters great dust and a part of coating cloud in the waste gas, then the waste gas gets into the work intracavity through first ventilation pipe, handles waste gas through the active carbon adsorbent, has alleviateed the processing load of active carbon adsorbent to the life of active carbon adsorbent is effectively prolonged and the treatment effect to waste gas, improves the reliability of use; when the activated carbon adsorbent needs to be desorbed, the first air valve on the first connecting air pipe communicated with the adsorption cavity where the activated carbon adsorbent is located is closed, waste gas does not enter the adsorption cavity any more, the third air valve and the second air valve communicated with the group of adsorption cavities are opened, high-temperature gas generated by combustion of the catalytic combustion device enters the adsorption cavity through the fourth connecting air pipe to desorb the activated carbon adsorbent, desorbed impurities enter the catalytic combustion device through the third connecting air pipe to be combusted to generate water vapor and carbon dioxide, after catalytic combustion, the fourth air valve is opened, waste gas generated by combustion is discharged into the second connecting air pipe through the fifth connecting air pipe, desorption treatment can be performed on the activated carbon adsorbent without stopping the machine, the whole working process is ensured, the practicability is improved, and the glass fiber paint blocking net is clamped through the support net and the press net, the convenient lacquer net that hinders to glass fiber carries out the dismouting, changes glass fiber filter equipment through the maintenance mouth convenience, supports the outer frame through left branch stay and right branch stay to fix a position the outer frame through the cooperation of multiunit semicircle constant head tank and multiunit semicircle reference column, can filter down the coating cloud that comes to glass fiber filter equipment through collecting the drawer and collect, then unified processing.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. An activated carbon adsorption catalytic combustion device comprises an adsorption box (1), a catalytic combustion device (2), a desorption fan (3) and a cooling air supplement fan (4), wherein a working cavity is arranged inside the adsorption box (1); it is characterized by further comprising a filter box (5), four groups of struts (6) and three groups of first connecting ventilation pipes (7), wherein the bottom ends of the four groups of struts (6) are respectively connected with the left front side, the right front side, the left rear side and the right rear side of the top end of the filter box (5), the top ends of the four groups of struts (6) are respectively connected with the left front side, the right front side, the left rear side and the right rear side of the bottom end of the adsorption box (1), two groups of partition plates (8) are arranged in the working cavity, the working cavity is divided into three groups of adsorption cavities by the two groups of partition plates (8), active carbon adsorption bodies (9) are arranged in the three groups of adsorption cavities, a second connecting air pipe (10) is arranged at the top end of the adsorption box (1), the second connecting air pipe (10) is communicated with the three groups of adsorption cavities, an exhaust fan (11) is arranged at the output end of the second connecting air pipe (10), a placing cavity is arranged, the left end of the filter box (5) is communicated with an air inlet pipeline (12), the bottom ends of the three groups of first connecting ventilation pipes (7) extend into the placing cavity from the top end of the filter box (5), the top ends of the three groups of first connecting ventilation pipes (7) extend into the three groups of adsorption cavities from the bottom end of the adsorption box (1) respectively, first air valves (32) are arranged on the three groups of first connecting ventilation pipes (7), three groups of third connecting air pipes (13) are arranged on the top end of the adsorption box (1), the three groups of third connecting air pipes (13) are communicated with the three groups of adsorption cavities respectively, second air valves (14) are arranged on the three groups of third connecting air pipes (13), the output ends of the three groups of third connecting air pipes (13) are communicated with the output end of the supplementary cooling fan (4), the output end of the supplementary cooling fan (4) is communicated with the input end of the catalytic combustion device (2), and the bottom end of the adsorption box (1) is communicated with three groups of fourth connecting air pipes (15, the bottom ends of the three groups of fourth communicating air pipes (15) are all communicated with the output end of the desorption fan (3), the input end of the desorption fan (3) is communicated with the output end of the catalytic combustion device (2), and the three groups of fourth communicating air pipes (15) are all provided with third air valves (16); the vertical two sets of baffles (17) that are provided with in top of placing the chamber, two sets of baffles (17) will place the top in chamber and separate into three groups and filter the cavity to all be provided with glass fiber filter equipment (18) in three groups filter the cavity, the bottom of three first ventilation pipes of group (7) communicates with each other with three groups of filter the cavity respectively.

2. The activated carbon adsorption catalytic combustion device according to claim 1, wherein the glass fiber filtering device (18) comprises an outer frame (19) and an inner frame (20), a plurality of layers of glass fiber paint-blocking nets (21) are arranged inside the outer frame (19), a supporting net (22) is arranged at the bottom end of the outer frame (19), the bottom end of each glass fiber paint-blocking net (21) is tightly attached to the top end of the supporting net (22), the inner frame (20) is arranged inside the outer frame (19) and at the top ends of the groups of glass fiber paint-blocking nets (21), a pressing net (23) is arranged at the bottom end of the inner frame (20), the bottom end of the pressing net (23) is tightly attached to the top ends of the plurality of layers of glass fiber paint-blocking nets (21), and the inner frame (20) is connected with the outer frame (19) through a lock catch.

3. The activated carbon adsorption catalytic combustion device according to claim 2, characterized in that the front end of the filter box (5) is provided with three sets of maintenance ports, the three sets of maintenance ports are respectively communicated with the three sets of filter chambers, the three sets of maintenance ports are respectively opposite to the three sets of glass fiber filter devices (18), and the three sets of maintenance ports are respectively provided with an opening and closing door (24).

4. An activated carbon adsorption catalytic combustion device according to claim 3, characterized in that the density of the multilayer glass fiber paint barrier net (21) becomes gradually denser from bottom to top.

5. The activated carbon adsorption catalytic combustion equipment of claim 4, wherein the left side wall and the right side wall of the filtering chamber are respectively provided with a left support bar (25) and a right support bar, the left side and the right side of the bottom end of the outer frame (19) are respectively contacted with the top ends of the left support bar (25) and the right support bar, the top ends of the left support bar (25) and the right support bar are respectively provided with a plurality of sets of semicircular positioning grooves (26), the bottom end of the outer frame (19) is provided with a plurality of sets of semicircular positioning columns (27), and the plurality of sets of semicircular positioning columns (27) are respectively located in the plurality of sets of semicircular positioning grooves (26).

6. The activated carbon adsorption catalytic combustion device according to claim 5, further comprising a fifth communicating air duct (28), wherein one end of the fifth communicating air duct (28) is communicated with the input end of the cool-supplementing air blower (4), the other end of the fifth communicating air duct (28) is communicated with the first communicating air duct (7), and a fourth air valve (29) is arranged on the fifth communicating air duct (28).

7. Activated carbon adsorption catalytic combustion device according to claim 6, characterized in that the output of the exhaust fan (11) is provided with a discharge chimney (30).

8. The activated carbon adsorption catalytic combustion device of claim 7, characterized in that the bottom of the front end of the filter box (5) is provided with three sets of collection drawers (31), and the three sets of collection drawers (31) are respectively positioned right below the three sets of glass fiber filtering devices (18).