JP5552201B2 - Exhaust deodorization method and deodorization apparatus - Google Patents

Description

  The present invention relates to a deodorizing method and a deodorizing apparatus for deodorizing exhaust gas containing odor generated in a kitchen or a food factory.

  As a method for easily deodorizing exhaust containing odor generated in a kitchen or a food factory, a method is known in which the odor components in the exhaust are adsorbed and removed by an adsorbent adsorbed with activated carbon or a metal oxide catalyst (patent) Reference 1). It is also known to oxidize and decompose odor components adsorbed on the adsorbent using ozone or OH radicals generated by ozone in order to improve the life of the adsorbent.

  Furthermore, in order to prevent secondary pollution due to discharge of unreacted ozone, a method of oxidatively decomposing odor components by circulatingly supplying ozone to the adsorbent is also known (see Patent Document 2).

JP 2004-136250 A JP 2005-152842 A

  However, according to the method of Patent Document 1, since the ozone contact time with the adsorbent is short, the decomposition promotion efficiency of odorous components by ozone cannot be increased. Usually, in the kitchen exhaust system, the exhaust contact time with the adsorbent is about 1 second at a maximum due to the limitation of the installation space with respect to the displacement and the limitation of the installation cost. On the other hand, the decomposition performance of odorous components can be improved by greatly increasing the amount of ozone supplied. However, if this is done, the amount of unreacted ozone will also increase significantly, so a new waste ozone treatment facility will be required on the downstream side. In addition, the replacement cost of the ozonolysis catalyst is added, and the blast power increases, so that the installation space, installation cost, and operation cost rise, making it impossible to be a practical system.

  In addition, according to the method of Patent Document 2 described above, the decomposition performance of odor components is enhanced by the circulation supply of ozone, but an ozone circulation system (blower, duct, etc.) is required separately from the normal deodorization system, and the installation space is reduced. There is a problem that the installation cost increases to about twice. If an ozone treatment system is added, the total installation space and installation cost further increase.

  The object of the present invention is to efficiently consume ozone and ozone decomposing components supplied upstream of the adsorbent material for decomposing odor components, thereby reducing the amount of unreacted ozone emissions, and reducing installation space and operating costs. It is an object of the present invention to provide a deodorizing method and a deodorizing apparatus for exhaust gas that can be completed.

According to the present invention, the odor component in the exhaust is adsorbed on the adsorbent to deodorize the odor component in the exhaust by exhausting the air containing the odor component through the flow path in which the adsorbent is arranged. The exhaust gas is exhausted at a lower flow rate than the deodorization treatment step through a deodorization treatment step to be adsorbed by the adsorbent and a bypass passage connected to the flow passage downstream of the adsorbent and having a smaller cross-sectional area than the flow passage. Meanwhile, an ozone treatment step of decomposing the odor component adsorbed on the adsorbent by supplying ozone or an ozone-decomposed component obtained by decomposing ozone upstream of the adsorbent in the flow path, The adsorbent is disposed in a diameter-enlarged portion in the flow path, and the ozone treatment process is performed at a time when air containing an odor component is not generated, and after the deodorization treatment process is stopped, a predetermined time has elapsed. Characterized by starting the ozone treatment step, deodorizing method of the exhaust gas is provided.

The average flow rate of exhaust gas in the ozone treatment step is, for example, 1/2 to 1/20 of the average flow rate of exhaust gas in the deodorization treatment step. Further, in the ozone treatment step, the supply amount of ozone or an ozone decomposition component obtained by decomposing ozone or the flow rate of exhaust gas may be controlled so that the ozone concentration downstream of the adsorbent is within a predetermined range. . Furthermore, in the ozone treatment step, the adsorbent may be heated, or the exhaust gas may be heated upstream of the adsorbent.

Further, according to the present invention, a blower provided in the flow path for exhausting air containing an odor component through the flow path, a bypass flow path connected to the flow path and having a smaller cross-sectional area than the flow path, , An air blower provided in the bypass channel, an adsorbent disposed in the channel, ozone for supplying ozone or an ozone-decomposing component into which the ozone is decomposed in the channel upstream of the adsorbent, and the like Supply means, wherein the bypass flow path is connected to the flow path downstream of the adsorbent , exhaust by operation of the blower provided in the flow path, and operation of the blower provided in the bypass flow path The adsorbent is disposed in the enlarged diameter portion in the flow path, and the ozone treatment process is performed at a time when air containing an odor component is not generated, and the deodorization treatment process is performed. Stop Then, after a predetermined time has elapsed, the ozone treatment process is started. In the deodorization treatment process, the blower provided in the flow path operates, and in the ozone treatment process, the blower provided in the bypass flow path operates. An exhaust gas deodorizing device is provided.

  An ozone concentration meter for detecting the ozone concentration of the exhaust gas is provided downstream of the adsorbent, and the supply amount of ozone or ozone decomposing component of the ozone supply device or the blowing device based on the detected value of the ozone concentration meter It may be configured to control the exhaust amount due to. Further, adjusting means for heating and humidifying the adsorbent, or adjusting means for heating and humidifying exhaust gas upstream of the adsorbent may be provided.

  According to the present invention, during the ozone treatment process for decomposing odor components, the ozone and ozone decomposition components supplied into the flow path upstream of the adsorbent are relatively slowly exhausted at a lower flow rate than in the deodorization treatment process. It is possible to pass through the adsorbent at a flow rate as described above, and the contact time of ozone and ozone decomposing components with the adsorbent can be made relatively long. By prolonging the decomposition treatment time, ozone and ozone decomposition components can be efficiently consumed for decomposition of odor components, and the emission amount of unreacted ozone can be reduced. In addition, by efficiently decomposing odor components adhering to the adsorbent with ozone and ozone decomposing components, the adsorption capacity of the adsorbent can be restored to high performance at low cost. In addition, since the amount of unreacted ozone is reduced, a large waste ozone treatment facility can be omitted, and the installation space, installation cost, and operation cost can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram of a deodorizing apparatus 1 according to the first embodiment of the present invention. In the first embodiment, an embodiment in which the present invention is applied to the exhaust of the kitchen 10 is shown. FIG. 2 is an explanatory diagram of a processing mode switching example of the deodorizing apparatus 1 according to the first embodiment.

  In the kitchen 10, air containing odor components including oil and smoke from the odor source 11 such as a stove is used during the daytime (for example, from 10:00 to 22:00, which is a business time in a restaurant). Occurs. A hood 12 disposed above the odor generating source 11 is provided on the ceiling of the kitchen 10, and in the kitchen 10, air containing odor components generated by the odor generating source 11 flows from the hood 12 to a flow path such as a duct. Through the inside 13, the air is sucked and exhausted outdoors by the power of the blower 15 arranged at the most downstream of the flow path 13.

  An oil mist removing filter 20 for attaching and removing oil mist is attached to the inner surface of the hood 12. In the air containing the odor component generated by the odor generation source 11, high-concentration oil mist is mixed in a floating state. By passing through the oil mist removal filter 20, the oil mist is 70 to 95. The air containing the odor component in a state where about% is removed is sucked into the flow path 13 and exhausted to the outside through the flow path 13 by the power of the blower 15 as a blower.

  The blower 15 is configured so that the flow rate of exhaust gas is variable by inverter control. The operating amount of the blower 15 is controlled by a command from the operation control panel 21 so that the flow rate of the exhaust gas in the flow path 13 is adjusted.

  An adsorbent 22 is arranged in the flow path 13 between the hood 12 and the blower 15. The adsorbent 22 is composed of, for example, a honeycomb structure impregnated with an adsorbent such as zeolite, and the surface (the surface of the adsorbent supported on the surface of the honeycomb structure or the like) is used as an ozone decomposition catalyst, for example, Metal oxide (not shown) such as manganese oxide is attached. In addition, when adsorbents such as zeolite are added in this way, the honeycomb structure or the like as the support itself may not have an adsorbing function. However, the adsorbent 22 may be any material as long as it can adsorb odor component gas, and is not particularly limited to a honeycomb structure, and may not necessarily have a configuration in which a metal oxide catalyst or the like is attached. The adsorbent used for the adsorbent 22 is not particularly limited as long as it can adsorb odor component gases such as silica gel and activated carbon. Further, a structure in which an adsorbing material such as zeolite is supported on the surface of a support member such as a honeycomb structure and an ozone decomposition catalyst such as a metal catalyst is further attached may be used. When applied to kitchen exhaust as in the first embodiment, it is desirable to support an incombustible zeolite or an adsorbent such as silica gel. Any metal oxide catalyst may be used as long as it can promote the decomposition of ozone. The entire adsorbent 22 made of a honeycomb structure or the like may be composed of an adsorbent such as zeolite or silica gel. Further, the adsorbent 22 can be configured by packing adsorbents such as activated carbon, zeolite, and silica gel into a bag shape. In addition, the adsorbent 22 may be configured by supporting an adsorbent such as activated carbon, zeolite, or silica gel on a splitter type (parallel plate type) structure, not limited to the honeycomb structure.

  The adsorbent 22 is disposed in the enlarged diameter portion 25 in the flow path 13. As a result, the contact area of the adsorbent 22 with the exhaust flowing in the flow path 13 is increased, and the flow rate of the exhaust when passing through the adsorbent 22 is made as slow as possible, so that the odor components contained in the exhaust can be reduced. 22 is adsorbed efficiently.

  In the first embodiment, the adsorbents 22a, 22b, and 22c having a thickness in the exhaust flow direction of about 15 cm are provided in three stages in the enlarged diameter portion 25 toward the exhaust flow direction. ing. The reason why the three-stage adsorbents 22a, 22b, and 22c are divided and arranged in the exhaust flow direction as the adsorbent 22 is as follows. That is, odorous components and dirt components such as oil mist contained in the exhaust gas adhere more toward the upstream side, so that the adsorption function of the odorous component first decreases in the most upstream side adsorbent 22a, and the intermediate adsorbent 22b falls next, and the most downstream adsorbent 22c falls last. Therefore, the three-stage adsorbents 22a, 22b, and 22c are dividedly arranged, and the adsorbent 22a on the most upstream side whose adsorbing function is reduced first is replaced. The adsorbent 22b and the most downstream adsorbent 22c are moved upstream one by one (that is, the adsorbent 22b that has been in the middle until now is moved to the most upstream position, and the most The adsorbent 22c at the downstream position is moved to an intermediate position), and a new adsorbent is replenished to the most downstream position. By adopting such a procedure, it is only necessary to replace the adsorbent 22 by 1/3, and the deodorizing material can be used more effectively than when the adsorbent 22 is not divided.

  An ozone supply nozzle 30 is inserted into the flow path 13 upstream of the adsorbent 22. The ozone supply nozzle 30 is disposed immediately downstream of the oil mist removal filter 20. In the first embodiment, ozone is supplied to the ozone supply nozzle 30 from an ozone generator 31 as a supply means such as ozone disposed outside the flow path 13. , Ozone is supplied upstream of the adsorbent 22.

  The operation of the ozone generator 31 as a supply means such as ozone is controlled by a command from the operation control panel 21 so that the amount of ozone supplied into the flow path 13 is adjusted.

  An ozone concentration meter 35 for detecting the ozone concentration in the exhaust exhausted to the outside through the flow path 13 is provided downstream of the blower 15. After passing through the adsorbent 22, the ozone concentration in the exhaust exhausted outdoors is detected by the ozone concentration meter 35 and input to the operation control panel 21. The operation control panel 21 controls the exhaust amount of the blower 15 as the air blowing means and the ozone supply amount by the ozone generator 31 as the ozone supplying means based on the detected value of the ozone concentration meter 35. Yes.

  In the deodorizing apparatus 1 according to the first embodiment configured as described above, for example, as shown in FIG. 2, the deodorizing process is performed for 12 hours between 10 o'clock and 22:00, which is the kitchen operating time. Further, during this time, in the kitchen 10, air containing an odor component including oil and smoke is generated from an odor generating source 11 such as a stove. Therefore, in the deodorizing process, air containing the odor component generated by the odor generating source 11 of the kitchen 10 is sucked into the flow path 13 from the hood 12 arranged on the ceiling of the kitchen 10 by the operation of the blower 15. By passing the adsorbent 22 disposed in the flow path 13, the odor component in the exhaust is adsorbed by the adsorbent 22 to deodorize the exhaust, and then exhausted outdoors.

  In this deodorizing treatment process, the blower 15 is normally blown, and the air containing the odor component generated by the odor generating source 11 of the kitchen 10 is forced into the flow path 13 from the hood 12 arranged on the ceiling of the kitchen 10. Suction and continuous ventilation with sufficient exhaust capacity to exhaust outside. In this deodorization treatment step, the contact time between the adsorbent 22 and the exhaust during the deodorization treatment is, for example, 0.25 seconds (adsorbent thickness 15 cm × 3 stages, average surface speed 1.8 m / s). In the deodorizing treatment step, the odor component in the exhaust gas is adsorbed as described above, so that the odor component is attached to the surface of the adsorbent 22.

  Next, for 2 hours from 22:00 to 0:00 after the deodorizing treatment step, the odor component adhering to a part of the metal oxide catalyst (not shown) adhering to the surface of the adsorbent 22 is used as a base material. The reaction surface of the metal oxide catalyst that can react with ozone is recovered by moving to the adsorbent on the adsorbent 22 side. The movement of odor components can be left to the natural adsorption effect of the adsorbent. Thus, after the deodorizing treatment process is stopped, a predetermined time (for example, 2 hours) for recovering the reaction surface of the metal oxide catalyst attached to the surface of the adsorbent 22 elapses. Stop air flow and stop exhaust.

  Then, after the reaction surface of the metal oxide catalyst on the surface of the adsorbent 22 is recovered in this way, an ozone treatment process is then performed for 5 hours from 0:00 to 5:00. In this ozone treatment process, the total air volume of the blower 15 is made smaller than that in the deodorization treatment process with respect to the normal air flow rate in the deodorization treatment process, and on the other hand, ozone generated by the ozone generator 31 is obtained from the adsorbent 22. Also, it is supplied into the flow path 13 from the ozone supply nozzle 30 upstream. As a result, the exhaust gas containing ozone and ozone decomposing components is supplied to the adsorbent 22 disposed in the flow path 13.

  Here, in the ozone treatment process, the operation control panel 21 reduces the total air volume of the blower 15 to about 1/6 of the total air volume in the deodorizing process and exhausts the air at a relatively slow wind speed. In this ozone treatment process, the contact time between the adsorbent 22 and the exhaust is, for example, about 0.25 × 6 = about 1.5 seconds (adsorbent thickness 15 cm × 3 stages, average surface speed 0.3 m / s). Yes, the contact time between ozone and the adsorbent 22 is also about 1.5 seconds.

  In the ozone treatment process, the operation control panel 21 controls the amount of ozone generated by the operation of the ozone generator 31 and adjusts the ozone concentration detected by the ozone concentration meter 35 to be in the range of 50 to 100 ppb. In this case, the amount of ozone generated can be controlled by a method such as adjusting the supply voltage to the ozone generator 31 or changing the operating time of the ozone generator 31. However, when the ozone concentration detected by the ozone concentration meter 35 is 50 ppb or less, the operation is continued with the operation of the ozone generator 31 as the maximum output. The operation control panel 21 controls the total air volume of the blower 15 instead of controlling the operation of the ozone generator 31 so that the ozone concentration detected by the ozone concentration meter 35 is in the range of 50 to 100 ppb. It can also be adjusted.

  In this way, in the ozone treatment process, ozone is supplied into the flow path 13 upstream of the adsorbent 22 while exhausting with a smaller air volume than in the deodorization treatment process at a time when no air containing odorous components is generated from the kitchen 10. As a result, the odor component adhering to the adsorbent 22 is decomposed by ozone and ozone decomposing components contained in the exhaust gas while blowing air at a slow wind speed to the adsorbent 22. Part of the ozone contained in the exhaust gas is decomposed by the action of the metal oxide catalyst on the surface of the adsorbent 22, and the ozone decomposition component thus decomposed (for example, OH radicals generated by ozone) is also adsorbed 22. It will function to decompose the odor components adhering to the surface.

  Then, after the ozone treatment process, for 6 hours from 4 o'clock to 10 o'clock, both the operation of the blower 15 and the operation of the ozone generator 31 are stopped, and the operation of the deodorizing apparatus 1 is stopped. At 10 o'clock, in the kitchen 10 again, air containing odor components including oil and smoke is generated from the odor generating source 11 such as a stove. At the same time, the deodorizing process is started.

  According to the deodorization apparatus 1 concerning the 1st Embodiment of this invention demonstrated above, in the ozone treatment process which decomposes | disassembles the odor component adhering to the adsorbent 22 with ozone or an ozone decomposition component, a deodorization treatment process is carried out. By exhausting at a smaller flow rate, the ozone and ozone decomposition components supplied into the flow path 13 upstream of the adsorbent 22 pass through the adsorbent 22 at a slower flow rate of about 1/6 compared to the deodorizing treatment process. The contact time of ozone and ozone decomposing components with the adsorbent 22 can be increased up to about six times. By prolonging the decomposition treatment time, ozone and ozone decomposition components can be efficiently consumed for decomposition of odor components, and the emission amount of unreacted ozone can be reduced. Further, when no air containing odorous components is generated from the kitchen 10, the odorous components adhering to the adsorbent 22 are efficiently decomposed by ozone or ozone decomposing components, and the remaining odorous components adhering to the catalyst are transferred to the adsorbent. As a result, the adsorption capacity of the adsorbent 22 can be restored to high performance at a low cost, and the life extension effect of the adsorbent 22 can be achieved.

  In addition, after the deodorizing treatment process is stopped, the activity of the metal oxide catalyst adhering to the surface of the adsorbent 22 is recovered by starting the ozone treatment process after a predetermined time (for example, 2 hours) has passed. , The ozone treatment process can be performed, and high ozone decomposition efficiency and bactericidal effect can be obtained. In the ozone treatment process, the air flow can be greatly reduced, and the contact time between ozone and the deodorizing material 22 and the metal oxide catalyst (not shown) can be increased. It can effectively act on deodorization. Also, the exhaust ozone concentration can be lowered to a very low level, eliminating the need for expensive deozonization equipment and reducing the installation space, installation cost, and operation cost.

  In addition, ozone reacts with a catalyst such as manganese to generate OH radicals. This OH radical decomposes the odor component and performs a deodorizing action. OH radicals also have a bactericidal action, thus killing spoilage bacteria and contributing to prevention of odor generation. By this sterilization action, the generation of bad odor on the inner surface of the flow path 13 can be prevented, and by supplying ozone at the most upstream part in the flow path 13 at a predetermined time every day, oil mist and odor components adhered to the inner surface of the flow path 13 Odor generation due to decay can be prevented at the same time. As in the first embodiment, when processing exhaust gas containing a large amount of oil mist that easily adheres to the inner surface of the flow path 13, the generation of malodor on the inner surface of the flow path 13 can be prevented by the sterilization action of ozone. It is desirable to arrange the ozone supply nozzle 30 as upstream as possible in the flow path 13 so that the inner surface of the flow path 13 can be sterilized with ozone or an ozone decomposition component immediately after the hood 12.

  In the ozone treatment process, the operation of the ozone generator 31 and the total air volume of the blower 15 are controlled so that the ozone concentration detected by the ozone concentration meter 35 is in the range of 50 to 100 ppb. Can be kept at a very low level, and at the same time, the decomposition efficiency of the odor component adhering to the adsorbent 22 can be kept at a high performance.

  Next, FIG. 3 is explanatory drawing of the deodorizing apparatus 2 concerning the 2nd Embodiment of this invention. In the second embodiment, an embodiment in which the present invention is applied to the exhaust of the food factory 40 is shown. FIG. 4 is an explanatory diagram of a processing mode switching example of the deodorizing apparatus 2 according to the second embodiment.

  In the food factory 40, air containing odorous components is generated during food processing operations during the daytime working hours. However, unlike the case of the above-described kitchen 10, the exhaust gas generated in the boiling process or the like in the air exhausted from the food factory 40 contains almost no oil or smoke. Therefore, in this example, in the second embodiment, air containing odor components generated in the food factory 40 is directly drawn into the flow path 13 such as a duct from the ceiling.

  As in the first embodiment of the present invention described above, a blower 15 is disposed on the most downstream side of the flow path 13. However, in the second embodiment, a bypass flow path 41 is connected to the flow path 13 upstream of the blower 15 at the most downstream side of the flow path 13, and another blower 42 is disposed in the bypass flow path 41. Has been. The bypass channel 41 has a smaller cross-sectional area than the channel 13, and the blowing capacity of the blower 42 provided in the bypass channel 41 is greater than the blowing capacity of the blower 15 provided in the flow path 13. small.

  In the flow path 13, a check damper 43 for preventing a backflow is provided immediately before the blower 15, and the suction portion of the bypass flow path 41 opens to the flow path 13 upstream of the check damper 43. Similarly, a check damper 44 is provided in the bypass channel 41 to prevent backflow. In addition, even if an automatic damper is provided instead of these check dampers 43 and 44, the outside air can be prevented from being sucked into the flow path 13 from the outside (back flow). However, the automatic damper has a higher initial cost.

  The operation of the blower 15 and the blower 42 is controlled by a command from the operation control panel 21, and exhaust by the operation of the blower 15 and exhaust by the blower 42 are selectively performed. As will be described later, in the deodorizing process for exhausting air containing odorous components generated in the food factory 40, the blower 15 is operated by a command from the operation control panel 21, and the exhaust gas is sent to the most downstream side of the flow path 13. The air is exhausted to the outside. On the other hand, in the ozone treatment process for decomposing odor components adhering to the adsorbent 22, the blower 45 is operated by a command from the operation control panel 21, and exhaust is drawn into the bypass flow path 41 in the middle of the flow path 13. It is designed to exhaust outside. In this case, the bypass channel 41 has a smaller cross-sectional area than the channel 13, and the blowing capacity of the blower 42 is smaller than the blowing capacity of the blower 15. It will be exhausted with a smaller flow rate. The exhaust is exhausted only from the bypass flow path by the action of the check damper.

  Similar to the first embodiment of the present invention described above, the adsorbent 22 is disposed in the enlarged diameter portion 25 formed in the flow path 13. Also in the second embodiment, the adsorbent 22 is composed of a honeycomb structure carrying an adsorbent having an adsorptive property such as zeolite, and the surface of the adsorbent 22 is, for example, manganese oxidation as an ozone decomposition catalyst. A metal oxide (not shown) such as an object is attached.

  However, in the second embodiment, the exhaust gas contains almost no oil or smoke, and the deterioration of the adsorbent 22 is not so severe. Therefore, in the second embodiment, the adsorbents 22a and 22b having a thickness of about 15 cm with respect to the exhaust flow direction are provided in two stages in the enlarged diameter portion 25 in the exhaust flow direction. Similarly, the upstream adsorbent 22a is sequentially replaced, the downstream adsorbent 22b is moved upstream, and a new adsorbent is replenished to the downstream position.

  An ozone supply nozzle 30 and a vapor supply nozzle 50 are inserted into the flow path 13 upstream of the adsorbent 22. The ozone supply nozzle 30 is supplied with ozone from an ozone generator 31 serving as ozone supply means disposed outside the flow path 13, and the vapor supply nozzle 50 is disposed as adjustment means disposed outside the flow path 13. Steam in a heated state is supplied from the steam supply source 51. By supplying the steam from the steam supply nozzle 50 into the flow path 13, the exhaust is heated and humidified upstream of the adsorbent 22, and the processing temperature when passing through the adsorbent 22 in the ozone treatment process is about 60 ° C. It is supposed to be.

  In the second embodiment, since oil, smoke, etc. are hardly contained in the exhaust gas, there is almost no adhesion of oil mist or the like to the inner surface of the flow path 13. Therefore, in the second embodiment, the ozone supply nozzle 30 is disposed immediately before the adsorbent 22. The steam supply nozzle 50 is disposed further upstream than the ozone supply nozzle 30 and is connected to a pipe branched from a steam pipe that leads directly to a boiler or the like from a boiler (not shown). The reason for supplying the steam is to generate sufficient OH radicals in addition to activating the reaction by raising the temperature of the catalyst. That is, it is difficult to generate OH radicals in a dry atmosphere, and moisture is added.

  The operation of the ozone generator 31 and the operation of the ozone generator 31 are controlled by a command from the operation control panel 21 so that the supply amount of ozone into the flow path 13 is adjusted.

  An ozone concentration meter 52 is provided downstream of the blower 42 in the bypass passage 41 to detect the ozone concentration in the exhaust exhausted to the outside through the bypass passage 41 in the ozone treatment process. After passing through the adsorbent 22, the ozone concentration in the exhaust gas drawn into the bypass channel 41 from the channel 13 and exhausted outdoors is detected by the ozone concentration meter 52 and input to the operation control panel 21. It has become. The operation control panel 21 controls the amount of ozone supplied by the ozone generator 31 as a supply means such as ozone based on the detected value of the ozone concentration meter 52.

  In the deodorizing apparatus 2 according to the second embodiment configured as described above, for example, as shown in FIG. 4, the next deodorizing process is performed at 10 hours between 8 o'clock and 18 o'clock, which is a food processing operation time. Done. During this time, in the food factory 40, air containing odorous components is generated with food processing operations. Therefore, in this deodorizing treatment step, the air containing the odor component generated in the food factory 40 is sucked into the flow path 13 by the operation of the blower 15 arranged at the most downstream of the flow path 13 and passes through the adsorbent 22. As a result, the odor component in the exhaust is adsorbed by the adsorbent 22 to deodorize the exhaust, and then exhausted to the outside through the flow path 13.

  In this deodorizing treatment process, the air is normally blown to the outside through the flow path 13, and the air containing the odor component generated in the food factory 40 is forcibly sucked into the flow path 13 and exhausted to the outside. Continuous ventilation with a large displacement. In this deodorizing process, the contact time between the adsorbent 22 and the exhaust during the deodorizing process is, for example, 0.2 seconds. In the deodorizing treatment step, the odor component in the exhaust gas is adsorbed as described above, so that the odor component is attached to the surface of the adsorbent 22.

  Next, after the deodorizing process, for 1 hour from 18:00 to 19:00, the blower 15 stops blowing and stops exhausting. Thereby, the metal oxide which can react with ozone by moving the odor component adhering to a part of the metal oxide catalyst (not shown) adhering to the surface of the adsorbent 22 to the adsorbent 22 side as a base material. Recover the reaction surface of the catalyst. The movement of odor components can be left to the natural adsorption effect of the adsorbent. In the second embodiment, since oil mist or the like hardly adheres to the surface of the adsorbent 22, the time for recovering the activity of the metal oxide catalyst surface adhering to the adsorbent 22 is also 1 It can be set to a time as short as time.

  Then, after the reaction surface of the metal oxide catalyst on the surface of the adsorbent 22 is recovered in this manner, an ozone treatment process is then performed for 15 hours from 17:00 to 8:00. In this ozone treatment step, the operation is switched to the operation of the blower 42 arranged in the bypass channel 41, air is sucked into the channel 13 from the food factory 40, and drawn into the bypass channel 41 in the middle of the channel 13. Exhaust outdoors. In this case, as described above, the bypass flow path 41 has a smaller cross-sectional area than the flow path 13, and the blowing capacity of the blower 42 is smaller than the blowing capacity of the blower 15. The air is exhausted at a lower flow rate than the normal blowing amount in the deodorizing process.

  On the other hand, in the ozone treatment process, ozone and steam are supplied from the ozone supply nozzle 30 and the steam supply nozzle 50 into the flow path 13 upstream of the adsorbent 22. As a result, the exhaust gas containing ozone and ozone decomposing components is supplied to the adsorbent 22 disposed in the flow path 13 while being heated by the steam.

  Here, in the ozone treatment process, by switching to the exhaust through the bypass passage 41 as described above, the total air volume is reduced to about 1/20 of the total air volume in the deodorizing treatment process, and is relatively slow. Exhaust at wind speed. In the ozone treatment process in the second embodiment, the contact time between the adsorbent 22 and ozone is, for example, about 4 seconds.

  Further, in the ozone treatment step, the steam is supplied from the steam supply nozzle 50 into the flow path 13, so that the exhaust is heated and humidified upstream of the adsorbent 22, and the treatment temperature when passing through the adsorbent 22 is about 60. It becomes ℃. As a result, the decomposition of ozone and the decomposition reaction of the odor component due to the ozone decomposition component (OH radical or the like) can be promoted. In this case, the processing temperature when passing through the adsorbent 22 is preferably about 30 ° C to 100 ° C. In addition, instead of supplying steam from the steam supply nozzle 50 into the flow path 13, by directly heating the adsorbent 22 with an electric heater or the like, similarly, the decomposition of ozone and the odor component due to the ozone decomposition product can be reduced. The decomposition reaction can be promoted.

  Further, during the ozone treatment process, the operation control panel 21 controls the amount of ozone generated by the operation of the ozone generator 31, and the ozone concentration detected by the ozone concentration meter 52 provided in the bypass channel 41 is in the range of 50 to 100 ppb. Adjust so that

  In this way, in the ozone treatment process, ozone is supplied into the flow path 13 upstream of the adsorbent 22 while exhausting with a smaller air volume than in the deodorization treatment process at a time when no air containing odorous components is generated from the food factory 40. By doing so, the odor component adhering to the adsorbent 22 is decomposed by ozone and ozone decomposing components contained in the exhaust gas while blowing air at a slow wind speed to the adsorbent 22.

  Then, at 8 o'clock after the ozone treatment process, the food processing operation is started again in the food factory 40, and accordingly, air containing odor components is generated. At the same time, the deodorizing process is started.

  According to the deodorization apparatus 2 concerning the 2nd Embodiment of this invention demonstrated above, the effect similar to the deodorization apparatus 1 concerning the 1st Embodiment of this invention demonstrated previously can be enjoyed. In addition, since the amount of air flow can be changed by switching the operation of the two air blowers 15 and 42 having different air blowing capacities, inverter control is not required, and only ON-OFF control is performed, so that control becomes easy. It is only necessary to add a small blower 42 having a small blowing capacity, so that the installation space is hardly increased. Steam and the like can be easily procured at the food factory 40. Moreover, by using the small air blower 42, the amount of air blown during the ozone treatment process can be further reduced, and the oxidative decomposition of odorous components by ozone can be further promoted. Furthermore, by letting the exhaust gas containing ozone flow at a low speed with a small air blower 42, the contact time between ozone and the reaction catalyst becomes longer, and ozone and ozone decomposition components are efficiently consumed by decomposing odor components, and unreacted. Ozone emissions can be reduced.

  Next, FIG. 5 is explanatory drawing of the deodorizing apparatus 3 concerning the 3rd Embodiment of this invention. This third embodiment shows an embodiment in which the present invention is applied to the exhaust of the kitchen 10, as in the first embodiment. FIG. 6 is an explanatory diagram of a processing mode switching example of the deodorizing apparatus 3 according to the third embodiment.

  The configuration of the deodorizing apparatus 3 according to the third embodiment is substantially the same as that of the deodorizing apparatus 1 according to the first embodiment described above, but the three-stage adsorbent 22 constituting the adsorbent 22. The metal oxide which is an ozonolysis catalyst is not attached to the surface of 'a, 22'b, 22'c. Instead, ozone is supplied to the ozone supply nozzle 30 via an ozone decomposition catalyst 60 from an ozone generator 31 serving as ozone supply means disposed outside the flow path 13. The ozone decomposition catalyst 60 contains a metal oxide such as manganese oxide, for example, and supplies ozone supplied from the ozone generator 31 into the flow path 13 from the ozone supply nozzle 30 as an ozone decomposition component. It has become. Moreover, in the deodorizing apparatus 3 of this 3rd Embodiment, the ozone concentration meter for detecting the ozone concentration in exhaust_gas | exhaustion is also abbreviate | omitted.

  In the deodorizing apparatus 3 according to the third embodiment configured as described above, for example, as shown in FIG. 6, the deodorizing treatment process is performed in 12 hours between 10 o'clock and 22:00, which is the kitchen operating time. Is the same as that of the first embodiment described above.

  However, in the deodorizing apparatus 3 according to the third embodiment, the ozone treatment process can be performed immediately after the deodorization treatment process, for example, for 4 hours between 22:00 and 2 o'clock.

  According to the deodorizing apparatus 2 concerning the 3rd Embodiment of this invention demonstrated above, the effect similar to the deodorizing apparatuses 1 and 2 concerning the 1st, 2nd embodiment of this invention demonstrated previously is demonstrated. You can enjoy it. In addition, in the third embodiment, since the decomposition of ozone is performed at a stage before being supplied into the flow path 13, the activity of the metal oxide catalyst as in the first and second embodiments. The air blow stop time for recovery can be omitted, and the ozone monitor on the downstream side is also unnecessary. According to the third embodiment, since the decomposition performance of ozone can be stably obtained, the decomposition and regeneration performance is predicted to increase when viewed from a long-term span, and the integrated deodorization processing time is considered to be longer. . The consumption of ozone is not expected to change.

  The present invention can be applied to the deodorizing treatment of exhaust gas containing odor generated in, for example, a kitchen or a food factory. The present invention is suitably applied to facilities where the generation of bad odor is not continuous for 24 hours. The present invention is suitable for deodorization of a facility having an exhaust stop time of at least 3 hours / day or 10 hours / week. In addition to oil mist (cutting oil from machine factories in addition to food processing) and kitchen exhaust, it can also be used for deodorizing organic solvents.

It is explanatory drawing of the deodorizing apparatus concerning the 1st Embodiment of this invention. It is explanatory drawing of the processing mode switching example of the deodorizing apparatus concerning 1st Embodiment. It is explanatory drawing of the deodorizing apparatus concerning the 2nd Embodiment of this invention. It is explanatory drawing of the processing mode switching example of the deodorizing apparatus concerning 2nd Embodiment. It is explanatory drawing of the deodorizing apparatus concerning the 3rd Embodiment of this invention. It is explanatory drawing of the processing mode switching example of the deodorizing apparatus concerning 3rd Embodiment.

Explanation of symbols

1, 2, 3 Deodorizing device 10 Kitchen 11 Odor generating source 12 Hood 13 Flow path 15 Blower 20 Oil mist removal filter 22 Adsorbent 25 Expanded diameter part 30 Ozone supply nozzle 31 Ozone generator 35 Ozone concentration meter 40 Food factory 41 Bypass flow Route 42 Blower 43, 44 Check damper 50 Steam supply nozzle 51 Steam supply source 52 Ozone concentration meter 60 Ozone decomposition catalyst

Claims (7)

A method of deodorizing by adsorbing odor components in exhaust gas to an adsorbent,
A deodorizing treatment process for adsorbing the odorous component in the exhaust to the adsorbent by exhausting the air containing the odorous component through the flow path in which the adsorbent is disposed;
The adsorbent is evacuated at a lower flow rate than the deodorizing treatment step through a bypass flow channel connected to the flow channel downstream of the adsorbent and having a smaller cross-sectional area than the flow channel. An ozone treatment step for decomposing odor components adsorbed on the adsorbent by supplying ozone or an ozone-decomposed component obtained by decomposing ozone upstream of the adsorbent,
The adsorbent is disposed in the enlarged diameter portion in the flow path,
The ozone treatment step is performed at a time when no air containing odorous components is generated,
A method for deodorizing exhaust gas, wherein the ozone treatment step is started after a predetermined time has elapsed since the deodorization treatment step was stopped. 2. The exhaust gas deodorization method according to claim 1, wherein an average exhaust gas flow rate in the ozone treatment step is 1/2 to 1/20 of an average exhaust gas flow rate in the deodorization treatment step. In the ozone treatment step, the supply amount of ozone or an ozone decomposition component obtained by decomposing ozone or the flow rate of exhaust gas is controlled so that the ozone concentration downstream of the adsorbent is within a predetermined range. Item 3. A method for deodorizing exhaust gas according to Item 1 or 2. The exhaust gas deodorization method according to any one of claims 1 to 3, wherein, in the ozone treatment step, the adsorbent is heated, or exhaust gas is heated upstream of the adsorbent. A blower provided in the flow path for exhausting air containing odor components through the flow path, a bypass flow path connected to the flow path and having a smaller cross-sectional area than the flow path, and provided in the bypass flow path comprising a blower that is, with the flow path arranged in the adsorbent, the ozone supply means for supplying ozone decomposing component ozone or ozone is decomposed in the flow path upstream of the adsorbent, the The bypass flow path is connected to the flow path downstream of the adsorbent, and exhaust by operation of the blower provided in the flow path and exhaust by operation of the blower provided in the bypass flow path are selectively performed. The adsorbent is disposed in the diameter-expanded portion in the flow path, and the ozone treatment process is performed at a time when air containing odor components is not generated, and after the deodorization treatment process is stopped, Time elapsed In addition, the ozone treatment process is started, and in the deodorization treatment process, a blower provided in the flow path is operated, and in the ozone treatment process, a blower provided in the bypass flow path is operated. Exhaust deodorization device. An ozone concentration meter that detects the ozone concentration of exhaust gas is provided downstream of the adsorbent, and based on the detected value of the ozone concentration meter, the supply amount of ozone or ozone-decomposed components by which ozone is decomposed based on the ozone concentration meter, Alternatively, the exhaust gas deodorizing device according to claim 5, wherein the exhaust gas deodorizing device is configured to control an exhaust amount by the blowing means. The exhaust deodorization apparatus according to claim 5 or 6, further comprising an adjusting means for heating and humidifying the adsorbent or an adjusting means for heating and humidifying the exhaust upstream of the adsorbent.

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