Purifying device for removing tail gas of fuming cupboard

Abstract

The invention belongs to the technical field of tail gas purification, and particularly relates to a purification device for removing tail gas of a fuming cupboard, which comprises a base, and further comprises a purification pipeline fixedly arranged at the upper end of the base, a humidity sensor, a gas flow rate sensor, a condensation dehumidification mechanism, a filtration adsorption mechanism, a water scraping cleaning mechanism, a condensation contact duration conversion mechanism and a flow rate and humidity feedback regulation mechanism are arranged at a gas inlet of the purification pipeline. According to the device, tail gas of the fuming cupboard can be effectively purified, moisture in the tail gas is effectively separated and removed before activated carbon is used for adsorption and purification, the problem that the adsorption efficiency of the activated carbon is greatly influenced due to the fact that the humidity of the tail gas is too high is solved, and the tail gas can be dehumidified when the tail gas is dehumidified. And water scraping cleaning is conducted on the condensation pipe at intervals, liquid drops formed on the condensation pipe are effectively scraped away, and the retention time of the tail gas in the condensation dehumidification mechanism can be automatically adjusted based on the humidity of the tail gas.

Description

Technical Field

[0001] The invention belongs to the technical field of tail gas purification, and in particular relates to a purification device for removing tail gas from a fume hood. Background Art

[0002] Fume hood exhaust refers to the gas discharged through the ventilation system after experiments, chemical operations or other processes involving the production of gaseous substances in the fume hood. During the experiment, exhaust with complex components, such as acid gas, is often produced. If it is not treated or treated improperly, it will not only harm the health of the experimenter, but also pollute the environment. Therefore, it is essential to purify the fume hood exhaust. For example, the patent with patent announcement number CN111888919B proposes a purification device for removing laboratory fume hood exhaust.

[0003] For large and complex chemical industry operations, the exhaust gas from the fume hoods is complex and diverse, and most of them are equipped with absorption towers to purify the exhaust gas. However, for small chemical industrial manufacturers, the amount of exhaust gas generated in the experiment is small, and the exhaust gas concentration is small. More often, activated carbon adsorption devices are used to complete the purification of the exhaust gas. Activated carbon has a highly developed pore structure, and these pores provide a huge specific surface area. When the exhaust gas passes through the activated carbon bed, harmful gas molecules (such as organic vapor, some inorganic small molecules, etc.) are adsorbed to the pore surface of the activated carbon under the action of van der Waals force. For organic solvent vapors such as benzene, toluene, and xylene that are common in the exhaust gas of chemical manufacturers' fume hoods, activated carbon can effectively adsorb them. However, activated carbon is sensitive to humidity. When the exhaust gas humidity is high, the adsorption efficiency may be reduced. When the exhaust gas humidity is high, water molecules and harmful gases Water molecules will compete for the adsorption sites on the surface of activated carbon. Water molecules are polar molecules and may have an advantage in number. The active sites on the surface of activated carbon are preferentially occupied by water molecules because water molecules can form hydrogen bonds and other interactions with certain functional groups on the surface of activated carbon (such as oxygen-containing functional groups). Harmful gas molecules (such as organic vapors) are mostly non-polar molecules and are at a disadvantage when competing with water molecules for adsorption sites. A large amount of water vapor condenses in the pores of activated carbon. Since water vapor is easily liquefied under low temperature or high humidity conditions, when the water vapor in the exhaust gas enters the pores of activated carbon, liquid water will be formed in the pores. These liquid water may block some pores, making it impossible for harmful gas molecules to enter the pores and be adsorbed, which will greatly affect the service life of the activated carbon. Failure to replace the activated carbon in time will lead to the re-release of pollutants, affecting the quality of exhaust gas purification treatment. Summary of the invention

[0004] The object of the present invention is to provide a purification device for removing exhaust gas from a fume hood in view of the above problems.

[0005] To achieve the above object, the present invention adopts the following technical solution: a purification device for removing exhaust gas from a fume hood, comprising a base, and also comprising: A purification pipeline is fixedly installed at the upper end of the base, and a humidity sensor and a gas flow rate sensor are installed at the air inlet of the purification pipeline; A condensation and dehumidification mechanism is installed on the purification pipeline; A filtering and adsorption mechanism is installed on the purification pipeline and is located at the rear side of the condensation and dehumidification mechanism; A water scraping and cleaning mechanism is fixedly mounted on the top of the condensation and dehumidification mechanism; A condensation contact time conversion mechanism, arranged on a side wall of the condensation and dehumidification mechanism; A flow rate and humidity feedback adjustment mechanism is fixedly mounted on the upper end of the base; A cleaning frequency control mechanism is fixedly mounted on the upper end of the base and is electrically connected to the wiper cleaning mechanism; A replacement prompt mechanism is fixedly mounted on the upper end of the base and is transmission-connected to the cleaning frequency control mechanism; A PLC controller is fixedly mounted on the upper end of the base, and the PLC controller is respectively electrically connected to the condensation and dehumidification mechanism, the wiper cleaning mechanism, the condensation contact time conversion mechanism, the flow rate and humidity feedback adjustment mechanism, the cleaning frequency control mechanism and the replacement prompt mechanism.

[0006] In the above-mentioned purification device for removing exhaust gas from a fume hood, the condensation and dehumidification mechanism includes a dehumidification shell fixedly connected to the purification pipe, a plurality of condensation tubes are evenly fixedly inserted on the top of the dehumidification shell, and a plurality of water receiving cylinders arranged corresponding to the positions of the condensation tubes are integrally connected to the bottom of the dehumidification shell.

[0007] In the above-mentioned purification device for removing exhaust gas from a fume hood, the filtering and adsorption mechanism includes two sealed shells that are symmetrically fixed and connected to the purification pipe, and an adsorption frame is detachably fixedly connected between the two sealed shells by bolts, and an activated carbon adsorption plate is fixedly installed on the inner wall of the adsorption frame.

[0008] In the above-mentioned purification device for removing exhaust gas from a fume hood, the wiper cleaning mechanism includes a U-shaped fixing plate fixedly mounted on the upper end of the dehumidification shell, and two reciprocating screws are symmetrically rotatably connected to the U-shaped fixing plate and the opposite side of the dehumidification shell. A bidirectional motor drive assembly for driving the two reciprocating screws to rotate synchronously is fixedly mounted on the upper end of the U-shaped fixing plate, and the two reciprocating screws are externally threadedly sleeved with the same lifting plate, and the lower end of the lifting plate is fixedly connected with multiple cleaning scraper rings through multiple lifting rods, and the cleaning scraper rings are sleeved on the outside of the condenser tube, and a through hole for the lifting rod to extend through is opened on the top of the dehumidification shell.

[0009] In the above-mentioned purification device for removing exhaust gas from a fume hood, the condensation contact time conversion mechanism includes a plurality of linear motors symmetrically fixedly connected to the outer wall of a dehumidification shell, the movable ends of the plurality of linear motors on the same side are fixedly connected to the same adjustment plate, a plurality of air guide plates are fixedly connected to the side of the adjustment plate close to the dehumidification shell, one end of the air guide plate away from the adjustment plate extends into the dehumidification shell, the air guide plate is sealed and movably connected to the dehumidification shell, and the plurality of air guide plates are located in the dehumidification shell to form a serpentine air guide channel.

[0010] In the above-mentioned purification device for removing exhaust gas from a fume hood, the flow rate and humidity feedback adjustment mechanism includes a feedback shell, the inner wall of the feedback shell is symmetrically fixedly connected to a plurality of first guide slide bars and a second guide slide bar arranged side by side, the plurality of first guide slide bars are externally slidably sleeved with the same first feedback plate, the lower end of the first feedback plate is fixedly connected to a first thrust permanent magnet plate, the bottom of the inner wall of the feedback shell is fixedly provided with a first thrust electromagnetic plate arranged opposite to the first thrust permanent magnet plate, the first feedback plate and the feedback shell are fixedly connected on one side opposite to each other with a plurality of first compensation springs sleeved on the outside of the first guide slide bar, and a flow rate feedback electromagnetic plate is fixedly provided on one side of the inner wall of the feedback shell. Resistance rod, one side of the first feedback plate is fixedly connected with a flow velocity feedback conductive contact electrically in contact with the flow velocity feedback resistance rod, multiple second guide slide bars are externally slidably sleeved with the same second feedback plate, the lower end of the second feedback plate is fixedly connected with a second thrust permanent magnet plate, the bottom of the inner wall of the feedback shell is fixedly provided with a second thrust electromagnetic plate arranged opposite to the second thrust permanent magnet plate, the second feedback plate and the feedback shell have a plurality of second compensation springs sleeved outside the second guide slide bar fixedly connected on the opposite side, a humidity feedback resistance rod is fixedly installed on one side of the inner wall of the feedback shell, and one side of the second feedback plate is fixedly connected with a humidity feedback conductive contact electrically in contact with the humidity feedback resistance rod.

[0011] In the above-mentioned purification device for removing exhaust gas from a fume hood, the cleaning frequency control mechanism includes a control shell, the inner wall of the control shell is rotatably connected to a reciprocating screw, the outer wall of the control shell is fixedly provided with a servo motor for driving the reciprocating screw to rotate, the rod wall of the reciprocating screw is threadedly sleeved with a starting plate, and one side of the inner wall of the control shell is fixedly provided with a starting switch arranged opposite to the starting plate.

[0012] In the above-mentioned purification device for removing exhaust gas from a fume hood, the replacement reminder mechanism includes a reduction gear box and a reminder round shell, one end of the reciprocating screw rod penetrates and extends out of the control shell, and is fixedly connected to the input end of the reduction gear box, a transmission shaft is rotatably connected to the center of the inner wall of the reminder round shell, the transmission shaft is fixedly connected to the output end of the reduction gear box, one end of the transmission shaft located in the reminder round shell is fixedly connected to an extension rod, and a pressing round head is fixedly connected to the rod wall of the end of the extension rod away from the transmission shaft, and a reminder switch corresponding to the position of the pressing round head is fixedly installed on the inner wall of the reminder round shell.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. Through the condensation and dehumidification mechanism, filtration and adsorption mechanism, and replacement reminder mechanism, the exhaust gas from the fume hood can be effectively purified, and the moisture in the exhaust gas can be effectively separated and removed before the activated carbon is used for adsorption evolution, thereby avoiding the problem that the exhaust humidity is too high and the adsorption efficiency of the activated carbon is too greatly affected, ensuring the adsorption and purification quality of the activated carbon, and being able to automatically calculate the adsorption saturation of the activated carbon based on the flow rate and humidity of the exhaust gas, and when the activated carbon is close to the saturation threshold, the staff is promptly reminded to make corresponding replacement treatments to avoid the problem that the saturated activated carbon cannot meet the purification needs and will instead cause the pollutants to be released again.

[0014] 2. By setting up the wiper cleaning mechanism, flow rate and humidity feedback adjustment mechanism, and cleaning frequency control mechanism, the condenser can be wiped and cleaned at intervals when dehumidifying the exhaust gas, and the droplets formed on the condenser can be effectively scraped off to avoid the adhesion of water droplets to form an insulating layer, thereby affecting the effective removal of moisture in the subsequent exhaust gas. The exhaust gas throughput can be determined based on the exhaust gas flow rate, and the frequency of cleaning and scraping can be automatically adjusted in combination with the humidity of the exhaust gas. The greater the exhaust gas flow rate and the greater the exhaust gas humidity, the higher the frequency of cleaning and scraping will be, thereby ensuring the timeliness of cleaning.

[0015] 3. Through the condensation contact time conversion mechanism, flow rate and humidity feedback adjustment mechanism, the residence time of the exhaust gas in the condensation and dehumidification mechanism can be automatically adjusted based on the humidity of the exhaust gas. The higher the exhaust gas humidity, the longer the residence time. Prolonging the contact time can give the water vapor in the exhaust gas more opportunities to contact the surface of the condenser tube with lower temperature, so that more water vapor can be condensed into liquid water and removed, and avoid the problem of unnecessary increase in system resistance due to the use of a longer residence time when the exhaust gas humidity is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a partial three-dimensional structural schematic diagram of the present invention; Figure 2It is a front view cross-sectional structural schematic diagram of the present invention; Figure 3 It is a cross-sectional structural schematic diagram of the condensation and dehumidification mechanism of the present invention; Figure 4 It is a three-dimensional cross-sectional structural schematic diagram of the filtering and adsorption mechanism of the present invention; Figure 5 It is a structural schematic diagram of the wiper cleaning mechanism of the present invention; Figure 6 It is a schematic diagram of a top view and cross-section structure of the condensation contact time conversion mechanism of the present invention; Figure 7 It is a cross-sectional structural schematic diagram of the flow rate and humidity feedback regulating mechanism of the present invention; Figure 8 It is a cross-sectional structural schematic diagram of the cleaning frequency control mechanism and the replacement prompt mechanism of the present invention.

[0017] In the figure: 1 base, 2 condensation dehumidification mechanism, 21 dehumidification shell, 22 condensation pipe, 23 water receiving cylinder, 3 filtering adsorption mechanism, 31 sealing shell, 32 adsorption frame, 33 activated carbon adsorption plate, 4 wiper cleaning mechanism, 41 U-shaped fixing plate, 42 reciprocating screw, 43 bidirectional motor drive assembly, 44 lifting plate, 45 lifting rod, 46 cleaning scraper ring, 5 condensation contact time conversion mechanism, 51 linear motor, 52 adjustment plate, 53 air guide plate, 6 flow rate and humidity feedback adjustment mechanism, 61 feedback shell, 62 first guide slide bar, 63 second guide slide bar, 64 first feedback plate, 65 first thrust permanent magnet plate, 66 first thrust electromagnetic plate, 67 first Compensation spring, 68 flow rate feedback resistor rod, 69 flow rate feedback conductive contact, 610 second feedback plate, 611 second thrust permanent magnet plate, 612 second thrust electromagnetic plate, 613 second compensation spring, 614 humidity feedback resistor rod, 615 humidity feedback conductive contact, 7 cleaning frequency control mechanism, 71 control shell, 72 reciprocating screw rod, 73 servo motor, 74 start plate, 75 start switch, 8 replacement prompt mechanism, 81 reduction gear box, 82 prompt round shell, 83 transmission shaft, 84 extension rod, 85 press round head, 86 prompt switch, 9 purification pipeline, 10 humidity sensor, 11 gas flow rate sensor, 12 PLC controller. Implementation

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0019] like Figure 1-Figure 8 As shown, a purification device for removing exhaust gas from a fume hood includes a base 1 and also includes: The purification pipeline 9 is fixedly installed at the upper end of the base 1, and a humidity sensor 10 and a gas flow rate sensor 11 are installed at the air inlet of the purification pipeline 9; The condensation and dehumidification mechanism 2 is installed on the purification pipe 9. The condensation and dehumidification mechanism 2 includes a dehumidification shell 21 fixedly connected to the purification pipe 9. A plurality of condensation tubes 22 are evenly fixedly inserted on the top of the dehumidification shell 21. A plurality of water receiving cylinders 23 corresponding to the positions of the condensation tubes 22 are integrally connected to the bottom of the dehumidification shell 21. The moisture contained in the exhaust gas can be effectively eliminated to avoid the problem that excessive moisture in the exhaust gas has an excessive impact on the adsorption performance of the activated carbon adsorption plate 33.

[0020] The filtering and adsorption mechanism 3 is installed on the purification pipe 9 and is located on the rear side of the condensation and dehumidification mechanism 2. The filtering and adsorption mechanism 3 includes two sealed shells 31 that are symmetrically fixed and connected to the purification pipe 9. An adsorption frame 32 is detachably fixedly connected between the two sealed shells 31 by bolts. An activated carbon adsorption plate 33 is fixedly installed on the inner wall of the adsorption frame 32, which can effectively purify the exhaust gas from the fume hood.

[0021] The wiper and cleaning mechanism 4 is fixedly mounted on the top of the condensation and dehumidification mechanism 2. The wiper and cleaning mechanism 4 includes a U-shaped fixing plate 41 fixedly mounted on the upper end of the dehumidification shell 21. The U-shaped fixing plate 41 and the dehumidification shell 21 are symmetrically rotatably connected with two reciprocating screws 42 on opposite sides. A bidirectional motor drive assembly 43 for driving the two reciprocating screws 42 to rotate synchronously is fixedly mounted on the upper end of the U-shaped fixing plate 41. The two reciprocating screws 42 are externally threadedly sleeved with the same lifting plate 44. The lower end of the lifting plate 44 is fixedly connected with multiple cleaning scraper rings 46 through multiple lifting rods 45. The cleaning scraper ring 46 is sleeved on the outside of the condenser tube 22. A through hole for the lifting rod 45 to extend through is opened on the top of the dehumidification shell 21. When the exhaust gas is dehumidified, the condenser tube 22 can be wiped and cleaned at intervals to effectively scrape off the droplets formed on the condenser tube 22 to avoid the problem of water droplets adhering to form an insulation layer, which further affects the effective removal of moisture in the subsequent exhaust gas.

[0022] The condensation contact time conversion mechanism 5 is installed on the side wall of the condensation and dehumidification mechanism 2. The condensation contact time conversion mechanism 5 includes multiple linear motors 51 symmetrically fixedly connected to the outer wall of the dehumidification shell 21. The moving ends of the multiple linear motors 51 on the same side are fixedly connected to the same adjustment plate 52. The side of the adjustment plate 52 close to the dehumidification shell 21 is fixedly connected to multiple air guide plates 53. The end of the air guide plate 53 away from the adjustment plate 52 extends into the dehumidification shell 21. The air guide plate 53 is sealed and movably connected to the dehumidification shell 21. The multiple air guide plates 53 are located in the dehumidification shell 21 to form a serpentine air guide channel, which can automatically adjust the air guide channel in the dehumidification shell 21 based on the humidity of the exhaust gas, adjust the contact time of the exhaust gas with the condenser 22, and ensure better dehumidification.

[0023] The flow rate and humidity feedback regulating mechanism 6 is fixedly installed on the upper end of the base 1. The flow rate and humidity feedback regulating mechanism 6 includes a feedback shell 61. The inner wall of the feedback shell 61 is symmetrically fixedly connected with a plurality of first guide slide bars 62 and a second guide slide bar 63 arranged side by side. The plurality of first guide slide bars 62 are externally slidably sleeved with the same first feedback plate 64. The lower end of the first feedback plate 64 is fixedly connected with a first thrust permanent magnet plate 65. A first thrust electromagnetic plate 66 arranged opposite to the first thrust permanent magnet plate 65 is fixedly installed at the bottom of the inner wall of the feedback shell 61. A plurality of first compensation springs 67 sleeved outside the first guide slide bar 62 are fixedly connected to the opposite side of the first feedback plate 64 and the feedback shell 61. A flow rate feedback resistor rod 68 is fixedly installed on one side of the inner wall of the feedback shell 61. One side of the feed plate 64 is fixedly connected with a flow velocity feedback conductive contact 69 which is in electrical contact with the flow velocity feedback resistor rod 68; a plurality of second guide slide bars 63 are slidably sleeved with the same second feedback plate 610; a second thrust permanent magnet plate 611 is fixedly connected to the lower end of the second feedback plate 610; a second thrust electromagnetic plate 612 which is arranged opposite to the second thrust permanent magnet plate 611 is fixedly installed at the bottom of the inner wall of the feedback shell 61; a plurality of second compensation springs 613 which are sleeved outside the second guide slide bar 63 are fixedly connected to the opposite side of the second feedback plate 610 and the feedback shell 61; a humidity feedback resistor rod 614 is fixedly installed on one side of the inner wall of the feedback shell 61; a humidity feedback conductive contact 615 which is in electrical contact with the humidity feedback resistor rod 614 is fixedly connected to one side of the second feedback plate 610.

[0024] The cleaning frequency control mechanism 7 is fixedly mounted on the upper end of the base 1 and is electrically connected to the wiper cleaning mechanism 4. The cleaning frequency control mechanism 7 includes a control shell 71. The inner wall of the control shell 71 is rotatably connected to a reciprocating screw 72. A servo motor 73 for driving the reciprocating screw 72 to rotate is fixedly mounted on the outer wall of the control shell 71. A starting plate 74 is threadedly sleeved on the rod wall of the reciprocating screw 72. A starting switch 75 arranged opposite to the starting plate 74 is fixedly mounted on one side of the inner wall of the control shell 71. The cleaning frequency of the condenser 22 can be automatically adjusted based on the flow rate and humidity of the exhaust gas to ensure timely cleaning.

[0025] The replacement prompt mechanism 8 is fixedly mounted on the upper end of the base 1 and is transmission-connected to the cleaning frequency control mechanism 7. The replacement prompt mechanism 8 includes a reduction gear box 81 and a prompt round shell 82. One end of the reciprocating screw 72 extends through the control shell 71 and is fixedly connected to the input end of the reduction gear box 81. A transmission shaft 83 is rotatably connected to the center of the inner wall of the prompt round shell 82. The transmission shaft 83 is fixedly connected to the output end of the reduction gear box 81. An extension rod 84 is fixedly connected to one end of the transmission shaft 83 located in the prompt round shell 82. A pressing round head 85 is fixedly connected to the rod wall at one end of the extension rod 84 away from the transmission shaft 83. A prompt switch 86 corresponding to the position of the pressing round head 85 is fixedly mounted on the inner wall of the prompt round shell 82.

[0026] The PLC controller 12 is fixedly mounted on the upper end of the base 1, and is electrically connected to the condensation and dehumidification mechanism 2, the wiper and cleaning mechanism 4, the condensation contact time conversion mechanism 5, the flow rate and humidity feedback adjustment mechanism 6, the cleaning frequency control mechanism 7 and the replacement reminder mechanism 8 respectively.

[0027] The operating principle of the present invention is described as follows: the exhaust gas from the fume hood is sent into the purification pipeline 9, and the exhaust gas first enters the dehumidification shell 21. The moisture in the exhaust gas is liquefied into small water droplets when passing through the condenser 22, and then the exhaust gas is dehumidified. The dehumidified exhaust gas then enters the sealing shell 31 and the adsorption frame 32, and the exhaust gas is purified by the activated carbon adsorption plate 33; The humidity and circulation speed of the exhaust gas are monitored in real time at the air inlet of the purification pipeline 9 through the gas flow rate sensor 11 and the humidity sensor 10. The PLC controller 12 controls the power supply device to supply power to the first thrust electromagnetic plate 66 and the second thrust electromagnetic plate 612 based on the monitoring values ​​fed back by the gas flow rate sensor 11 and the humidity sensor 10. The first thrust electromagnetic plate 66 and the second thrust electromagnetic plate 612 are energized to generate the same magnetism as the first thrust permanent magnet plate 65 and the second thrust permanent magnet plate 611, respectively, thereby driving the first feedback plate 64 and the second feedback plate 610 to move up along the first guide slide bar 62 and the second guide slide bar 63, respectively. Specifically, when the gas flow rate sensor 11 detects that the gas flow rate of the exhaust gas is greater, the PLC controller 12 controls the power supply device to supply a greater current to the first thrust electromagnetic plate 66, thereby causing the first feedback plate 64 to overcome the elastic force of the first compensation spring 67 and slide a greater distance, and simultaneously driving the flow rate feedback conductive contact 69 to slide a greater distance on the flow rate feedback resistor rod 68, so that the access resistance value of the flow rate feedback resistor rod 68 is smaller; When the humidity sensor 10 detects that the humidity of the exhaust gas is greater, the PLC controller 12 controls the power supply device to supply a greater current to the second thrust electromagnetic plate 612, thereby causing the humidity feedback conductive contact 615 to slide a greater distance on the humidity feedback resistor rod 614, so that the access resistance value of the humidity feedback resistor rod 614 is smaller; When the humidity sensor 10 detects that the humidity of the exhaust gas is greater, the PLC controller 12 synchronously controls the linear motor 51 to drive the adjustment plate 52 to move a greater distance, so that the two adjustment plates 52 bring the multiple air guide plates 53 located on both sides closer to each other, thereby lengthening the distance that the exhaust gas moves in the dehumidification shell 21, and increasing the contact time between the exhaust gas and the condenser 22, so that the water vapor in the exhaust gas has more opportunities to contact the surface of the condenser 22 with a lower temperature, so that more water vapor can be condensed into liquid water and removed; During the exhaust gas purification process, the PLC controller 12 synchronously controls the servo motor 73 to operate, and the servo motor 73 drives the reciprocating screw 72 to rotate. The threaded sleeve effect of the reciprocating screw 72 and the start plate 74 makes the start plate 74 reciprocate in the control shell 71 until the start plate 74 presses on the start switch 75, indicating that the water droplets accumulated on the condenser 22 have reached the level that needs to be cleaned. At this time, the PLC controller 12 controls the bidirectional motor drive component 43 to work, and the bidirectional motor drive component 43 drives the two reciprocating screws 42 to rotate. The threaded sleeve effect of the reciprocating screw 42 and the lifting plate 44 makes the lifting plate 44 cooperate with the lifting rod 45 to drive the cleaning scraper 46 to move up and down back and forth, and the cleaning scraper 46 is used to scrape off the water droplets attached to the condenser 22, so that the water droplets fall into the water receiving tube 23; When the reciprocating screw 72 rotates, it drives the input end of the reduction gear box 81 to rotate, and then drives the transmission shaft 83 to rotate slowly through the reduction gear box 81 until the transmission shaft 83 rotates one circle. At this time, the extension rod 84 drives the pressing round head 85 to press the prompt switch 86, indicating that the use of the activated carbon adsorption plate 33 is close to saturation. The PLC controller 12 transmits a wireless signal to the receiving terminal of the staff to remind the staff to replace the activated carbon adsorption plate 33 in time to ensure the purification quality of the exhaust gas; The velocity feedback conductive contact 69 and the velocity feedback resistor rod 68 are connected in series to the power supply circuit of the servo motor 73, and the humidity feedback conductive contact 615 and the humidity feedback resistor rod 614 are also connected in series to the power supply circuit of the servo motor 73. The servo motor 73 is a DC motor. The greater the gas velocity of the exhaust gas, the smaller the access resistance of the velocity feedback resistor rod 68. The greater the humidity of the exhaust gas, the smaller the access resistance of the humidity feedback resistor rod 614. The synchronization will increase the power supply current of the servo motor 73, thereby increasing the speed of the servo motor 73, shortening the interval time of the start plate 74 pressing the start switch 75, and increasing the cleaning frequency of the condenser 22. The increase in the exhaust gas velocity will cause more exhaust gas to contact the condenser 22 per unit time, so that more water is removed and left on the condenser 22. The greater the humidity, the more water droplets will be formed on the condenser 22 per unit time. Increasing the cleaning frequency makes the cleaning of the condenser 22 more timely and self-regulating. At the same time, the interval time of pressing the round head 85 on the reminder switch 86 will be shortened, so that the reminder interval time for replacing the activated carbon adsorption plate 33 is shorter. The increase in the gas flow rate of the exhaust gas will make the activated carbon adsorption plate 33 have more exhaust gas to absorb per unit time, making the saturation speed of the activated carbon adsorption plate 33 faster. The greater the humidity in the exhaust gas means that even after dehumidification by the condensation and dehumidification mechanism 2, more moisture will not be intercepted and filtered. The moisture will affect the adsorption quality of the activated carbon adsorption plate 33, making the activated carbon adsorption plate 33 reach a faster speed at which it can no longer absorb. The self-adjustment of the corresponding reminder interval time can make the replacement of the activated carbon adsorption plate 33 more timely.

[0028] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A purification device for removing exhaust gas from a fume hood, comprising a base (1), characterized in that: Also includes: A purification duct (9) is fixedly mounted on the upper end of the base (1), and a humidity sensor (10) and a gas flow rate sensor (11) are mounted at the air inlet of the purification duct (9); a condensation and dehumidification mechanism (2) is mounted on the purification duct (9); a filtering and adsorption mechanism (3) is mounted on the purification duct (9) and is located at the rear side of the condensation and dehumidification mechanism (2); a water scraping and cleaning mechanism (4) is fixedly mounted on the top of the condensation and dehumidification mechanism (2); a condensation contact time conversion mechanism (5) is mounted on the side wall of the condensation and dehumidification mechanism (2); and a flow rate and humidity feedback adjustment mechanism (6) is fixedly mounted on the base ( 1); a cleaning frequency control mechanism (7) fixedly mounted on the upper end of the base (1) and electrically connected to the wiper cleaning mechanism (4); a replacement prompting mechanism (8) fixedly mounted on the upper end of the base (1) and transmission-connected to the cleaning frequency control mechanism (7); a PLC controller (12) fixedly mounted on the upper end of the base (1), the PLC controller (12) being electrically connected to the condensation and dehumidification mechanism (2), the wiper cleaning mechanism (4), the condensation contact time conversion mechanism (5), the flow rate and humidity feedback adjustment mechanism (6), the cleaning frequency control mechanism (7) and the replacement prompting mechanism (8), respectively.

2. A purification device for removing exhaust gas from a fume hood according to claim 1, characterized in that: The condensation and dehumidification mechanism (2) comprises a dehumidification shell (21) fixedly connected to the purification pipe (9), a plurality of condensation tubes (22) are evenly and fixedly inserted on the top of the dehumidification shell (21), and a plurality of water receiving cylinders (23) arranged corresponding to the positions of the condensation tubes (22) are integrally connected to the bottom of the dehumidification shell (21).

3. A purification device for removing exhaust gas from a fume hood according to claim 1, characterized in that: The filtering and adsorption mechanism (3) comprises two sealing shells (31) which are symmetrically fixed and connected to the purification pipe (9); an adsorption frame (32) is detachably fixedly connected between the two sealing shells (31) by bolts; an activated carbon adsorption plate (33) is fixedly mounted on the inner wall of the adsorption frame (32).

4. A purification device for removing exhaust gas from a fume hood according to claim 2, characterized in that: The wiper cleaning mechanism (4) comprises a U-shaped fixing plate (41) fixedly mounted on the upper end of the dehumidification shell (21); two reciprocating screws (42) are symmetrically rotatably connected to the U-shaped fixing plate (41) and the dehumidification shell (21) on opposite sides; a bidirectional motor drive assembly (43) for driving the two reciprocating screws (42) to rotate synchronously is fixedly mounted on the upper end of the U-shaped fixing plate (41); the two reciprocating screws (42) are externally threadedly sleeved with a same lifting plate (44); the lower end of the lifting plate (44) is fixedly connected to a plurality of cleaning scraper rings (46) via a plurality of lifting rods (45); the cleaning scraper rings (46) are sleeved outside the condensation tube (22); and a through hole for the lifting rods (45) to penetrate and extend is opened at the top of the dehumidification shell (21).

5. A purification device for removing exhaust gas from a fume hood according to claim 2, characterized in that: The condensation contact time conversion mechanism (5) comprises a plurality of linear motors (51) symmetrically fixedly connected to the outer wall of the dehumidification shell (21); the movable ends of the plurality of linear motors (51) located on the same side are fixedly connected to the same adjustment plate (52); a plurality of air guide plates (53) are fixedly connected to a side of the adjustment plate (52) close to the dehumidification shell (21); an end of the air guide plate (53) away from the adjustment plate (52) extends through the dehumidification shell (21); the air guide plate (53) is sealingly and movably connected to the dehumidification shell (21); and the plurality of air guide plates (53) are located in the dehumidification shell (21) to form a serpentine air guide channel.

6. A purification device for removing exhaust gas from a fume hood according to claim 1, characterized in that: The flow rate and humidity feedback adjustment mechanism (6) comprises a feedback shell (61), the inner wall of the feedback shell (61) is symmetrically fixedly connected to a plurality of first guide slide bars (62) and second guide slide bars (63) arranged side by side, the plurality of first guide slide bars (62) are slidably sleeved with a same first feedback plate (64) outside, the lower end of the first feedback plate (64) is fixedly connected to a first thrust permanent magnet plate (65), a first thrust electromagnetic plate (66) arranged opposite to the first thrust permanent magnet plate (65) is fixedly installed at the bottom of the inner wall of the feedback shell (61), a plurality of first compensation springs (67) sleeved outside the first guide slide bars (62) are fixedly connected to the opposite side of the first feedback plate (64) and the feedback shell (61), a flow rate feedback resistor rod (68) is fixedly installed on one side of the inner wall of the feedback shell (61), and one side of the first feedback plate (64) is fixedly connected to the first feedback plate (64). A flow rate feedback conductive contact piece (69) electrically in contact with a flow rate feedback resistor rod (68) is connected; a plurality of second guide slide bars (63) are slidably sleeved with a same second feedback plate (610); a second thrust permanent magnet plate (611) is fixedly connected to the lower end of the second feedback plate (610); a second thrust electromagnetic plate (612) arranged opposite to the second thrust permanent magnet plate (611) is fixedly mounted on the bottom of the inner wall of the feedback shell (61); a plurality of second compensation springs (613) sleeved outside the second guide slide bar (63) are fixedly connected to opposite sides of the second feedback plate (610) and the feedback shell (61); a humidity feedback resistor rod (614) is fixedly mounted on one side of the inner wall of the feedback shell (61); and a humidity feedback conductive contact piece (615) electrically in contact with the humidity feedback resistor rod (614) is fixedly connected to one side of the second feedback plate (610).

7. A purification device for removing exhaust gas from a fume hood according to claim 1, characterized in that: The cleaning frequency control mechanism (7) comprises a control housing (71), the inner wall of the control housing (71) being rotatably connected to a reciprocating screw rod (72), the outer wall of the control housing (71) being fixedly provided with a servo motor (73) for driving the reciprocating screw rod (72) to rotate, the rod wall of the reciprocating screw rod (72) being threadedly sleeved with a start plate (74), and a start switch (75) being fixedly provided on one side of the inner wall of the control housing (71) and being arranged opposite to the start plate (74).

8. A purification device for removing exhaust gas from a fume hood according to claim 7, characterized in that: The replacement prompt mechanism (8) comprises a reduction gear box (81) and a prompt circular shell (82); one end of the reciprocating screw rod (72) penetrates and extends out of the control shell (71) and is fixedly connected to the input end of the reduction gear box (81); a transmission shaft (83) is rotatably connected to the center of the inner wall of the prompt circular shell (82); the transmission shaft (83) is fixedly connected to the output end of the reduction gear box (81); an extension rod (84) is fixedly connected to one end of the transmission shaft (83) located in the prompt circular shell (82); a pressing round head (85) is fixedly connected to the rod wall of one end of the extension rod (84) away from the transmission shaft (83); and a prompt switch (86) corresponding to the position of the pressing round head (85) is fixedly installed on the inner wall of the prompt circular shell (82).

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