Exhaust gas treatment apparatus

Abstract

To efficiently treat exhaust gas discharged from a working space in which atmosphere is controlled.SOLUTION: An exhaust gas treatment device 10 is a device for treating exhaust gas discharged through a flow path 2 from a work space 1S in which the atmosphere is controlled, and includes an adsorber 3 that is provided in the middle of the flow path 2, into which the exhaust gas is introduced, and in which an adsorbent that adsorbs toxic gas contained in the exhaust gas is housed. an oxidation reaction vessel 5 that is provided in the flow path 2 on the downstream side of the adsorber 3, into which the exhaust gas discharged from the adsorber 3 is introduced, and in which a catalytic converter that oxidizes the toxic gas contained in the exhaust gas is housed. a control unit 7 that controls the catalytic converter heating unit 6 so as to heat the catalytic converter when the exhaust gas is discharged from the work space 1S to the flow path 2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an apparatus for treating exhaust gases emitted from an atmosphere-controlled workspace. [Background technology]

[0002] When handling harmful chemicals, substances, etc. in research institutes, factories, etc., glove boxes with airtight working spaces are used to ensure the safety of workers, as exemplified in Patent Document 1. Furthermore, when the work involves the production (e.g., prototyping or mass production) of lithium ion batteries, electronic devices, etc., and oxidation or humidity (i.e., oxygen or moisture) must be avoided, such airtight working spaces are filled with an inert gas, such as argon gas, or dry air as the atmospheric gas.

[0003] Glove boxes are manufacturing equipment used for prototype production and small-scale production. When mass-producing products such as lithium-ion batteries and electronic devices in factories, dry rooms and clean rooms are set up within the factory, and production lines are built within these rooms to manufacture the products. Dry rooms and clean rooms maintain a certain degree of airtightness, just like glove boxes, and the atmosphere in the work space is controlled. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-081452 Summary of the Invention [Problem to be solved by the invention]

[0005] Depending on the type of work being done in the work space, exhaust gases containing toxic gases such as hydrocarbons and carbon monoxide may be emitted from the glove box. Hydrocarbons and carbon monoxide can be purified (e.g., oxidative combustion treatment by catalytic reaction) using precious metal catalysts such as rhodium (Rh), platinum (Pt), and palladium (Pd). However, in order for the precious metal catalyst to undergo a catalytic reaction, it is necessary to constantly heat the precious metal catalyst to a predetermined temperature (e.g., about 200°C to about 400°C).

[0006] On the other hand, the pressure inside the glove box during operation fluctuates due to, for example, the introduction of gas into the work space or the generation of gas in the work space. Due to such pressure fluctuations, exhaust gas is irregularly discharged from the glove box during operation. It is not efficient to keep the precious metal catalyst constantly heated in order to treat the irregularly discharged exhaust gas.

[0007] An object of the present invention is to efficiently treat exhaust gases discharged from a work space in which the atmosphere is controlled. [Means for solving the problem]

[0008] The present invention for solving the above problems includes, for example, the following aspects. (Section 1) An apparatus for treating exhaust gas discharged from an atmosphere-controlled working space through a circulation path, an adsorber provided in the flow path, into which the exhaust gas is introduced, and containing an adsorbent that adsorbs toxic gases contained in the exhaust gas; an oxidation reactor that is provided in the flow path downstream of the adsorber, into which the exhaust gas discharged from the adsorber is introduced, and that contains a catalyst that oxidizes toxic gases contained in the exhaust gas; a catalyst heating unit that heats the catalyst; a control unit that controls the catalyst heating unit so as to heat the catalyst when the exhaust gas is discharged from the working space to the circulation path; An exhaust gas treatment device comprising: (Section 2) further comprising an adsorbent heating unit that heats the adsorbent; Item 2. The exhaust gas treatment device according to item 1, wherein the control unit further controls the adsorbent heating unit so as to heat the adsorbent when the temperature of the catalyst reaches a predetermined temperature. (Section 3) the distribution path is provided to divide the exhaust gas discharged from the working space and introduce it into each of the plurality of adsorber devices, and to introduce the exhaust gas discharged from each of the adsorber devices into the oxidation reactor, an adsorbent heating unit that heats the adsorbent accommodated in the adsorbent is provided for each of the plurality of adsorbers; Item 3. The exhaust gas treatment device according to item 2, wherein the control unit controls each of the one or more adsorbent heating units to switch between the one or more adsorbent heating units that heat the adsorbent. (Section 4) Item 4. The exhaust gas treatment device according to any one of Items 1 to 3, wherein the adsorbent adsorbs acidic gases contained in the toxic gases. (Section 5) Item 5. The exhaust gas treatment device according to any one of items 1 to 4, further comprising an oxygen introducing section in the flow path upstream of the oxidation reactor that introduces a gas containing oxygen into the flow path. (Section 6) Item 6. The exhaust gas treatment device according to any one of items 1 to 5, further comprising an exhaust gas heating unit that heats the exhaust gas, in the flow path upstream of the adsorber. (Section 7) Item 7. The exhaust gas treatment device according to any one of items 1 to 6, wherein the adsorbent adsorbs at least one of hydrocarbons and carbon monoxide contained in the toxic gas. (Section 8) 8. The exhaust gas treatment device according to any one of items 1 to 7, wherein the adsorbent adsorbs organic gases contained in the toxic gas. (Section 9) Item 9. The exhaust gas treatment device according to any one of items 1 to 8, wherein the working space is filled with an atmospheric gas, and the exhaust gas further contains the atmospheric gas after work. [Effects of the Invention]

[0009] According to the present invention, exhaust gas discharged from a work space in which the atmosphere is controlled can be efficiently treated. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram of an exhaust gas treatment device according to an embodiment of the present invention. [Figure 2] 1A to 1C are diagrams for explaining various modes in which exhaust gas is discharged from a glove box. [Figure 3] FIG. 10 is a block diagram of an exhaust gas treatment device according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and drawings, the same reference numerals will denote the same or similar components, and therefore, redundant descriptions of the same or similar components will be omitted.

[0012] [Device configuration] FIG. 1 is a block diagram of an exhaust gas treatment device according to one embodiment of the present invention.

[0013] An exhaust gas treatment device (hereinafter also simply referred to as device) 10 (10A) according to one embodiment is a device for treating exhaust gas discharged from an atmosphere-controlled workspace 1S through a flow path 2. In this embodiment, an airtight workspace 1S provided in a glove box 1 will be described as an example of an atmosphere-controlled workspace. The device 10 according to one embodiment includes an adsorber 3, an adsorbent heating section 4, an oxidation reactor 5, a catalyst heating section 6, a control section 7, an oxygen introduction section 8, and an exhaust gas heating section 9. The adsorbent heating section 4, the oxygen introduction section 8, and the exhaust gas heating section 9 may have any configuration.

[0014] In the exhaust gas treatment device 10 according to one embodiment, the catalyst is heated when exhaust gas is discharged from the working space 1S into the flow path 2. The exhaust gas discharged from the working space 1S until the catalyst exhibits its purification performance is purified by an adsorber arranged upstream of the catalyst. This makes it possible to treat the exhaust gas discharged from the working space 1S intermittently, thereby enabling efficient treatment of the exhaust gas.

[0015] Work space In this embodiment, an airtight work space 1S is provided in a glove box 1. The glove box 1 has a work space 1S that is isolated from the outside air, and is configured so that a worker can work in the work space 1S using gloves (not shown) provided in a plurality of armholes 1h. Examples of the glove box 1 include a vacuum type shown in FIG. 2(A) and a gas replacement type (purge type) shown in FIG. 2(B), which will be described later. In this embodiment, a vacuum type glove box 1 will be described as an example.

[0016] A solenoid valve 13 is provided at the outlet of the work space 1S. The solenoid valve 13 is normally closed when the glove box 1 is in use, ensuring airtightness of the work space 1S. A pressure sensor (not shown) is provided within the work space 1S. When the pressure sensor detects a change in pressure within the work space 1S, it sends a control signal to the control unit 7 indicating that exhaust gas is to be discharged from the work space 1S. In this embodiment, upon receiving the control signal sent from the pressure sensor, the control unit 7 opens the solenoid valve 13, thereby discharging exhaust gas from the work space 1S to the distribution channel 2.

[0017] Toxic gases The exhaust gas discharged from the glove box 1 contains toxic gases corresponding to the work carried out in the work space 1S. Examples of toxic gases contained in the exhaust gas include hydrocarbons, carbon monoxide, benzene, toluene, hydrogen sulfide, and chlorine. Of these toxic gases, benzene and toluene are organic gases produced, for example, from organic solvents, while hydrogen sulfide and chlorine are acidic gases. For example, the humidity in the airtight work space 1S provided in the glove box 1 is approximately 1 ppm or less, and the oxygen concentration is approximately 1 ppm or less.

[0018] Atmospheric gas The work space 1S can be filled with atmospheric gas, and the exhaust gas can contain the atmospheric gas after work. Examples of the atmospheric gas include inert gases such as N2, Ar, and He, and dry air. In order to replenish the atmospheric gas in response to fluctuations in the pressure within the work space 1S, atmospheric gas can be introduced into the work space 1S from an atmospheric gas supply source 14 through an atmospheric gas inlet path 15. The flow rate of the atmospheric gas can be adjusted by a solenoid valve 16 provided in the atmospheric gas inlet path 15.

[0019] Distribution Channel The flow path 2 is a tubular flow path for discharging the exhaust gas discharged from the airtight working space 1S. An adsorber 3, an oxidation reactor 5, an oxygen introduction unit 8, and an exhaust gas heating unit 9, which will be described later, are provided in the flow path along the flow path 2. The exhaust gas discharged from the working space 1S is purified by these units 3, 5, 8, and 9 provided along the flow path 2 before being released into the atmosphere. The exhaust gas purified by the device 10 is released through the flow path 2, for example, into the atmosphere.

[0020] Adsorbent (adsorbent) The adsorber 3 contains an adsorbent (not shown) that adsorbs toxic gases contained in the exhaust gas. The adsorber 3 is disposed in the flow path 2 downstream of the working space 1S. The exhaust gas is introduced into the adsorber 3 through the flow path 2. In this embodiment, a blower 11 is provided in the flow path 2 upstream of the adsorber 3, and the exhaust gas discharged from the working space 1S is introduced into the adsorber 3 by the blower 11.

[0021] An oxidation reactor 5 is disposed in the flow path 2 downstream of the adsorber 3. A catalyst is housed in the oxidation reactor 5. The adsorbent housed in the adsorber 3 adsorbs toxic gases contained in the exhaust gas until the catalyst housed in the oxidation reactor 5 reaches an appropriate temperature of approximately 200°C to approximately 400°C. This makes it possible to properly purify the exhaust gas discharged from the working space 1S until the catalyst demonstrates its purification performance, thereby enabling efficient treatment of the exhaust gas.

[0022] The adsorbent adsorbs at least one of hydrocarbons and carbon monoxide contained in the toxic gas. Preferably, the adsorbent can adsorb organic gases contained in the toxic gas. More preferably, the adsorbent can adsorb acidic gases contained in the toxic gas. Acidic gases are catalyst poisons, and if acidic gases such as hydrogen sulfide and chlorine are contained in the exhaust gas discharged from the working space 1S, the catalytic performance of the catalyst will be reduced. Therefore, it is preferable to arrange the adsorber 3 containing the adsorbent upstream of the oxidation reactor 5 containing the catalyst so that the acidic gases are pre-adsorbed upstream of the catalyst.

[0023] The adsorbent may be, for example, activated carbon or zeolite. Both natural and synthetic zeolites may be used as the zeolite. The zeolite used as the adsorbent in this embodiment can adsorb toxic gases contained in the exhaust gas, such as hydrocarbons, carbon monoxide, benzene, toluene, hydrogen sulfide, and chlorine.

[0024] Adsorbent heating section The adsorbent heating unit 4 is disposed around the adsorber 3 and heats the adsorbent contained in the adsorber 3. The adsorbent is heated to, for example, about 200°C to about 400°C. The adsorbent heating unit 4 can be, for example, an electric heater.

[0025] When the adsorbent housed in the adsorber 3 is heated, the toxic gas molecules adsorbed on the adsorbent are desorbed, thereby restoring the adsorption performance of the adsorbent. The toxic gas molecules desorbed from the adsorbent are purified by a catalyst in the oxidation reactor 5 located downstream of the adsorber 3.

[0026] Oxidation reactor (catalyst) The oxidation reactor 5 contains a catalyst (not shown) that oxidizes toxic gases contained in the exhaust gas. The oxidation reactor 5 is disposed in the flow path 2 downstream of the adsorber 3. The exhaust gas discharged from the adsorber 3 is introduced into the oxidation reactor 5 through the flow path 2.

[0027] The catalyst may be a precious metal catalyst such as rhodium (Rh), platinum (Pt), or palladium (Pd). The catalyst purifies toxic gases contained in the exhaust gas by oxidizing the toxic gases through a catalytic reaction. Examples of toxic gases that are oxidized by the catalyst include hydrocarbons and carbon monoxide. In this embodiment, the exhaust gas purified by the catalyst is released into the atmosphere from an exhaust port located downstream of the oxidation reactor 5.

[0028] ·Catalyst heating section The catalyst heating unit 6 is disposed around the oxidation reactor 5 and heats the catalyst housed in the oxidation reactor 5. The catalyst is heated to, for example, about 200°C to about 400°C. The catalyst heating unit 6 can be, for example, an electric heater.

[0029] Control unit The control unit 7 controls each component of the device 10. The control unit 7 controls the operation of, for example, the adsorbent heating unit 4, the catalyst heating unit 6, the exhaust gas heating unit 9, the blower 11, and the solenoid valves 12, 13, and 16. The control unit 7 controls the catalyst heating unit 6 to heat the catalyst when exhaust gas is discharged from the working space 1S to the distribution channel 2. The control unit 7 further controls the adsorbent heating unit 4 to heat the adsorbent when the temperature of the catalyst reaches a predetermined temperature. The control unit 7 may include, for example, a processor such as a CPU and a memory. The control unit 7 may be, for example, a single-board computer such as a Raspberry Pi or Arduino (registered trademark). Transmission and reception of control signals or control data between the control unit 7 and each component of the device 10 may be wired or wireless.

[0030] Oxygen introduction section The oxygen introducing unit 8 is disposed in the flow path 2 upstream of the oxidation reactor 5 (upstream of the oxidation reactor 5 in the flow path 2) and introduces an oxygen-containing gas into the flow path 2. The oxygen introducing unit 8 is, for example, a tubular flow path, and the flow rate of the oxygen-containing gas is adjusted, for example, by a solenoid valve 12 provided upstream of the oxygen introducing unit 8. The oxygen-containing gas may be, for example, the ambient air of the device 10. In this embodiment, the oxygen-containing gas is introduced into the flow path 2 from the oxygen introducing unit 8 by a blower 11.

[0031] In the oxidation reactor 5, toxic gases contained in the exhaust gas, such as hydrocarbons and carbon monoxide, are oxidized using a catalyst to purify the exhaust gas. Oxidation using a catalyst requires oxygen gas to oxidize the toxic gases to be treated. In other words, if the exhaust gas does not contain enough oxygen gas, the toxic gases contained in the exhaust gas cannot be sufficiently purified in the oxidation reactor 5.

[0032] The oxygen introducing section 8 introduces a gas containing oxygen into the flow path 2 upstream of the oxidation reactor 5, thereby promoting the oxidation treatment of the toxic gas by the catalyst in the oxidation reactor 5. As a result, even if the atmospheric gas in the working space 1S does not contain a sufficient amount of oxygen gas, for example, if the atmospheric gas in the working space 1S is an inert gas such as N2, Ar, or He, the toxic gas to be treated can be oxidized in the oxidation reactor 5.

[0033] Exhaust gas heating section The exhaust gas heating unit 9 is disposed in the flow path 2 upstream of the oxidation reactor 5 (upstream of the oxidation reactor 5 in the flow path 2) and heats the exhaust gas. The exhaust gas heating unit 9 heats the introduced exhaust gas to, for example, about 200°C to about 400°C. For example, an electric heater can be used as the exhaust gas heating unit 9.

[0034] The exhaust gas heating unit 9 starts operating and heating the exhaust gas, for example, at the same time that the catalyst heating unit 6 starts heating the catalyst. The exhaust gas heating unit 9 assists the catalyst heating by the catalyst heating unit 6. In other words, the exhaust gas heating unit 9 functions as a pre-heating unit for the catalyst heating unit 6. For example, when the flow rate of exhaust gas discharged from the working space 1S to the flow path 2 is relatively high, it takes a relatively long time for the catalyst contained in the oxidation reactor 5 to rise to an appropriate temperature of approximately 200°C to approximately 400°C using only heating by the catalyst heating unit 6. In contrast, if the temperature of the exhaust gas to be introduced into the oxidation reactor 5 is previously raised using the exhaust gas heating unit 9, the time required for the catalyst to rise to an appropriate temperature can be shortened.

[0035] Preferably, the exhaust gas heating unit 9 is arranged in the flow path 2 upstream of the adsorber 3 (upstream of the adsorber 3 in the flow path 2). When the exhaust gas heating unit 9 is arranged in the flow path 2 upstream of the adsorber 3, the temperature of the exhaust gas to be introduced into the adsorber 3 can be increased in advance, and the recovery of the adsorption performance of the adsorbent contained in the adsorber 3 can be promoted. The adsorber 3 is arranged in the flow path 2 upstream of the oxidation reactor 5. Therefore, when the exhaust gas heating unit 9 is arranged in the flow path 2 upstream of the adsorber 3, not only can the recovery of the adsorption performance of the adsorbent be promoted, but also the time required for the catalyst to rise to an appropriate temperature can be shortened.

[0036] The temperatures of the exhaust gas discharged from the working space 1S and the oxygen-containing gas introduced through the oxygen introduction section 8 are generally room temperature (20°C ± 15°C). The adsorber 3 and the oxidation reactor 5 are heated to approximately 200°C to approximately 400°C. Therefore, if these room-temperature exhaust gases and oxygen-containing gases are introduced directly into the adsorber 3 and the oxidation reactor 5 through the flow path 2, the adsorber 3 and the oxidation reactor 5 (particularly the upstream portion of the adsorber 3) will be constantly cooled. In contrast, if the exhaust gas and oxygen-containing gas introduced into the adsorber 3 and the oxidation reactor 5 through the flow path 2 are preheated using the exhaust gas heating section 9, the adsorber 3 and the oxidation reactor 5 will be able to function uniformly regardless of the location where the gas is introduced.

[0037] [Operation procedure] The procedure for operating an exhaust gas processing device 10 according to one embodiment will be described. Steps S1 to S4 described below are the startup sequence of the device 10, and steps S5 to S7 are the shutdown sequence of the device 10. When the device 10 is in a standby state, it performs a series of intermittent operations shown in steps S1 to S7 every time it receives a control signal transmitted from the pressure sensor. When the exhaust gas processing device 10 is able to intermittently process the exhaust gas discharged from the working space 1S, the exhaust gas processing device 10 can efficiently process the exhaust gas.

[0038] First, we will explain the situation before the device 10 in standby mode starts operation. For example, a worker is using gloves with multiple armholes 1h to fabricate a prototype of, for example, a lithium-ion battery in an airtight workspace 1S provided in a glove box 1. The workspace 1S is filled with inert gas. As the prototype is fabricated, toxic gas is generated in the workspace 1S. Exhaust gas containing toxic gas is irregularly discharged from the workspace 1S into the distribution channel 2.

[0039] When a pressure sensor provided in the work space 1S detects a change in pressure in the work space 1S, a control signal indicating that exhaust gas will be discharged from the work space 1S is sent to the control unit 7. The device 10, which is in a standby state, is triggered by the control signal sent from the pressure sensor to start the startup sequence shown in steps S1 to S4.

[0040] In step S1, upon receiving a control signal transmitted from the pressure sensor, the control unit 7 starts operation of the catalyst heating unit 6 to begin heating the catalyst housed in the oxidation reactor 5. The control unit 7 then starts operation of the blower 11, which has been stopped, and then opens the solenoid valve 13 to discharge the exhaust gas from the working space 1S to the distribution path 2. Until the catalyst reaches an appropriate temperature of approximately 200°C to approximately 400°C, the adsorbent housed in the adsorber 3 purifies the toxic gas contained in the exhaust gas. It is preferable that the control unit 7 does not start operation of the adsorbent heating unit 4 until the temperature of the catalyst reaches an appropriate temperature. The time required from the start of the process in step S1 until the solenoid valve 13 opens is, for example, several seconds.

[0041] In step S2, the control unit 7 operates the catalyst heating unit 6 to maintain the temperature of the catalyst housed in the oxidation reactor 5 at an appropriate temperature. After the temperature of the catalyst has stabilized at an appropriate temperature of about 200°C to about 400°C, the catalyst housed in the oxidation reactor 5 purifies the toxic gases contained in the exhaust gas, replacing the adsorbent housed in the adsorber 3. The time required from the start of the process of step S2 until the temperature of the catalyst is stabilized at the appropriate temperature is, for example, about 30 minutes.

[0042] In step S3, the control unit 7 starts the operation of the adsorbent heating unit 4 to start heating the adsorbent housed in the adsorber 3. As a result, toxic gases contained in the exhaust gas are purified by the catalyst housed in the oxidation reactor 5, while the adsorption performance of the adsorbent arranged upstream of the catalyst is restored.

[0043] In step S4, the control unit 7 opens the solenoid valve 12 to activate the oxygen introducing unit 8, thereby introducing an oxygen-containing gas (e.g., the ambient air) into the flow path 2. In the oxidation reactor 5, the oxygen-containing gas introduced from the oxygen introducing unit 8 promotes the purification of the exhaust gas.

[0044] After step S4, the device 10 maintains an operating state and treats the exhaust gas discharged from the working space 1S while the pressure sensor detects a pressure change in the flow path 2. While in the operating state, the device 10 can intermittently repeat the process of step S3, which restores the adsorption performance of the adsorbent. When the device 10 is in the operating state, for example, the pressure sensor does not detect a pressure change in the flow path 2 and a predetermined time (e.g., about 30 minutes) has elapsed, the device 10 starts the shutdown sequence shown in steps S5 to S7.

[0045] In step S5, the control unit 7 stops the operation of the adsorbent heating unit 4 to lower the temperature of the adsorbent. In this embodiment, the adsorbent and adsorbent heating unit 4 are naturally cooled to, for example, room temperature by the surrounding atmosphere (for example, room temperature of approximately 27°C). When the temperature of the adsorbent drops, the adsorbent becomes able to purify toxic gases contained in the exhaust gas again. Until the temperature of the adsorbent drops to about room temperature, the catalyst contained in the oxidation reactor 5 purifies toxic gases contained in the exhaust gas. By continuing to operate the catalyst heating unit 6, the temperature of the catalyst contained in the oxidation reactor 5 is maintained at an appropriate temperature.

[0046] In step S6, the control unit 7 stops the operation of the catalyst heating unit 6 to lower the temperature of the catalyst. In this embodiment, the catalyst and catalyst heating unit 6 are naturally cooled by the surrounding atmosphere. After the temperature of the catalyst drops below an appropriate temperature of approximately 200°C to approximately 400°C, the adsorbent contained in the adsorber 3 purifies the toxic gases contained in the exhaust gas, instead of the catalyst contained in the oxidation reactor 5. The temperature of the adsorbent has already been lowered to approximately room temperature in step S5, and the adsorbent is capable of purifying the toxic gases contained in the exhaust gas.

[0047] In step S7, the control unit 7 closes the solenoid valve 12 to stop the operation of the oxygen introducing unit 8, thereby stopping the introduction of the oxygen-containing gas into the flow path 2. The control unit 7 then closes the solenoid valve 13 and stops the blower 11. After step S7, the device 10 enters a standby state again. As exemplified in this embodiment, the timing for stopping the operation of the oxygen introducing unit 8 is preferably after the timing for stopping the operation of the adsorbent heating unit 4 and the catalyst heating unit 6. This is because introducing the oxygen-containing gas at room temperature into the flow path 2 from upstream of the adsorbent heating unit 4 and the catalyst heating unit 6 promotes natural cooling of the adsorbent heating unit 4 and the catalyst heating unit 6.

[0048] Thereafter, the device 10 in the standby state performs a series of intermittent operations shown in steps S1 to S7 every time it receives a control signal transmitted from the pressure sensor.

[0049] As described above, the exhaust gas processing device 10 according to one embodiment of the present invention can efficiently process the exhaust gas discharged from the working space in which the atmosphere is controlled.

[0050] [Other forms] Although the present invention has been described above with reference to specific embodiments, the present invention is not limited to the above-described embodiments.

[0051] In the above embodiment, the glove box 1 is of a vacuum type, but the manner in which the glove box 1 discharges exhaust gas is not limited to a vacuum type. The glove box 1 may be of a gas replacement type (purge type), for example.

[0052] FIG. 2 is a diagram illustrating various modes in which a glove box discharges exhaust gas. In the vacuum-type glove box 1 shown in FIG. 2(A), when the glove box 1 is used, the atmosphere in the work space 1S is evacuated (or slightly reduced in pressure) by directly exhausting the atmosphere therein using, for example, a blower 21 (or a vacuum pump 21). Thereafter, the atmosphere in the work space 1S is replaced by introducing atmospheric gas from an atmospheric gas supply source 14 into the work space 1S through an atmospheric gas inlet 15. In the gas-replacement-type glove box 1 shown in FIG. 2(B), when the glove box 1 is used, the atmosphere in the work space 1S is replaced by introducing atmospheric gas from an atmospheric gas supply source 14 into the work space 1S through an atmospheric gas inlet 15. The component designated by the reference numeral 22 is a solenoid valve.

[0053] Furthermore, the glove box 1 may be equipped with a gas circulation and purification device 30 as shown in FIG. 2(C). Various known gas circulation and purification devices can be used for the gas circulation and purification device 30. The illustrated gas circulation and purification device 30 contains an adsorbent 31, and the atmosphere in the work space 1S is introduced into the adsorbent 31 through a circulation path 32. The adsorbent 31 purifies the atmosphere in the work space 1S. The adsorbent 31 may be the same adsorbent as the adsorbent contained in the adsorber 3. A heating unit (not shown) may be provided around the adsorbent 31. Solenoid valves 22 are provided at the inlet and outlet of the circulation path 32. The component designated by reference numeral 33 is a blower, and the component designated by reference numeral 34 is a solenoid valve.

[0054] In the above embodiment, the airtight workspace 1S provided in the glove box 1 is an example of a workspace with a controlled atmosphere. However, the exhaust gas treated by the exhaust gas treatment device 10 is not limited to the exhaust gas discharged from the airtight workspace 1S provided in the glove box 1. The exhaust gas treatment device 10 can also treat exhaust gas discharged from, for example, a dry room or a clean room where lithium-ion batteries or electronic devices are manufactured. Generally, a dry room or a clean room is a workspace where a certain degree of airtightness is maintained, and the atmosphere of the workspace is controlled. In this specification, the term "airtight workspace" does not only mean a workspace where almost complete airtightness is maintained, such as the workspace 1S of the glove box 1 exemplified in the above embodiment, but also means a workspace where a certain degree of airtightness is maintained and the atmosphere is controlled, such as a dry room or a clean room. For example, the humidity in a dry room is approximately 100 ppm, and the oxygen concentration is approximately 21%, which is similar to that of the atmosphere.

[0055] Furthermore, if the glove box 1 is provided with a side box (not shown) that communicates with the work space 1S, the exhaust gas processing device 10 can also process exhaust gases discharged from the space within such a side box. The side box communicates with the work space 1S and is used to carry items into and out of the work space 1S. In this specification, the work space does not only mean the work space 1S of the glove box 1 exemplified in the above embodiment, but also means a space that communicates with the work space 1S (for example, the space within the side box).

[0056] In the above embodiment, the exhaust gas treatment device 10 (10A) includes one adsorber 3, and the control unit 7 targets the adsorbent heating units 4 arranged around one adsorber 3, but the number of adsorber 3 and adsorbent heating units 4 is not limited to this. In another embodiment, the exhaust gas treatment device 10 (10B) includes multiple adsorber 3a, 3b connected in parallel, and the control unit 7 can control each of the adsorbent heating units 4a, 4b to switch between one or more adsorbents to be heated from among the multiple adsorbents.

[0057] FIG. 3 is a block diagram of an exhaust gas treatment device according to another embodiment of the present invention. In this embodiment, as illustrated in FIG. 3, a first adsorber 3a and a second adsorber 3b are connected in parallel via a flow path 2. The flow path 2 is configured to split the exhaust gas discharged from the working space 1S and introduce it into each of the multiple adsorber 3a, 3b, and introduce the exhaust gas discharged from each of the adsorber 3a, 3b into an oxidation reactor 5. Each of the multiple adsorber 3a, 3b is provided with an adsorbent heater 4a, 4b that heats the adsorbent accommodated in the adsorber 3a, 3b. The first adsorbent heater 4a is disposed around the first adsorber 3a and heats the adsorbent (not shown) accommodated in the first adsorber 3a. The second adsorbent heater 4b is disposed around the second adsorber 3b and heats the adsorbent (not shown) accommodated in the second adsorber 3b. The control unit 7 controls the first adsorbent heater 4a and the second adsorbent heater 4b to switch between one or more adsorbent heaters 4a and 4b that heat the adsorbent. The lower the temperature of the adsorbent contained in the adsorber 3a and adsorber 3b, the higher the adsorption efficiency. Therefore, the control unit 7 preferably controls either the first adsorbent heater 4a or the second adsorbent heater 4b to heat the adsorbent, for example, periodically. For example, the adsorbent 3a is heated to restore its adsorption performance, while the other adsorbent 3b, not heated, is allowed to cool and its adsorption efficiency increases. After a predetermined time has elapsed, the adsorbent to be heated is switched, and the adsorbent 3b is heated to restore its adsorption performance, while the adsorbent 3a is not heated but its temperature is lowered to increase its adsorption efficiency. Alternatively, the control unit 7 may periodically control both the first adsorbent heater 4a and the second adsorbent heater 4b to heat the adsorbent.

[0058] In the section of the flow path 2 in which the first adsorber 3a and the second adsorber 3b are arranged in parallel, a plurality of solenoid valves 17a to 17d are provided in the flow path 2. The control unit 7 adjusts the flow rate of the exhaust gas in the parallel section of the flow path 2 by controlling the solenoid valves 17a to 17d in response to switching of the adsorbent to be heated.

[0059] In the above embodiment, the exhaust gas purified by the catalyst is released into the atmosphere from an exhaust port located downstream of the oxidation reactor 5. However, the treatment of the exhaust gas purified by the catalyst is not limited to this. In another embodiment, as illustrated in FIG. 3, a secondary combustion unit 18 (afterburner furnace 18) can be further provided downstream of the oxidation reactor 5 to further purify the exhaust gas purified by the catalyst. The secondary combustion unit 18 heats the introduced exhaust gas to, for example, about 650°C to about 800°C. The secondary combustion unit 18 can combust substances contained in the exhaust gas, such as dioxins. Targeted dioxins include polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs).

[0060] In the above embodiment, the catalyst housed in the oxidation reactor 5 purifies hydrocarbons and carbon monoxide contained in toxic gases by oxidation treatment, but the catalytic reaction by the catalyst is not limited to oxidation treatment. The catalyst housed in the oxidation reactor 5 can also perform reduction treatment in addition to oxidation treatment. In this case, the catalyst can purify hydrocarbons and carbon monoxide contained in toxic gases, for example, nitrogen oxides (NO x ) can be purified by reduction treatment, and the exhaust gas treatment device 10 can also treat exhaust gases containing nitrogen oxides.

[0061] In the above embodiment, the opening and closing operation of the solenoid valve 13 is controlled by the control unit 7, but the entity that controls the opening and closing operation of the solenoid valve 13 is not limited to the control unit 7. For example, the worker using the glove box 1 may open and close the solenoid valve 13. In this case, for example, a pressure sensor provided in the work space 1S may notify the worker that exhaust gas is being discharged from the work space 1S using means (notification means) that emits light or sound, such as an LED lamp or a speaker. The same applies to the solenoid valves 12 and 16.

[0062] In the above embodiment, the blower 11 is stopped when the device 10 is in a standby state, and starts operating when the control unit 7 receives a control signal transmitted from the pressure sensor, but the operation timing of the blower 11 is not limited to the illustrated embodiment. Regardless of the operating state (operating state or standby state) of the device 10, the blower 11 may always operate (operate continuously) while the solenoid valve 12 is open. In addition, the blower 11 can also control the flow rate of the exhaust gas flowing through the distribution path 2 by, for example, being inverter-controlled.

[0063] In the above embodiment, the adsorbent and the adsorbent heating unit 4 are naturally cooled to, for example, room temperature by the surrounding air (e.g., room temperature of approximately 27°C), but the manner of lowering the temperature of the adsorbent is not limited to this. In another embodiment, the control unit 7 first opens, for example, the solenoid valve 12 and then operates the blower 11 to actively introduce air into the adsorbent and the adsorbent heating unit 4 and actively lower the temperature of the adsorbent to, for example, approximately 100°C. The control unit 7 then stops the blower 11, and the adsorbent is naturally cooled to room temperature without actively introducing air. In another embodiment, the process of operating the blower 11 to actively introduce air into the adsorbent and the adsorbent heating unit 4 is not performed continuously until the temperature of the adsorbent drops to approximately room temperature, but is performed until the temperature of the adsorbent drops to approximately 100°C, which is higher than room temperature. This is because if air is actively introduced continuously until the temperature of the adsorbent drops to approximately room temperature, the adsorbent will adsorb organic matter contained in the actively introduced cooling air, reducing the adsorption capacity of the adsorbent compared to when it is naturally cooled. [Explanation of symbols]

[0064] 1 glove box 1h Armhole 1S work space 2. Distribution Channels 3(3a,3b) Adsorber 4(4a,4b) Adsorbent heating section 5. Oxidation reactor 6 Catalyst heating section 7 Control Unit 8 Oxygen introduction section 9 Exhaust gas heating section 10 (10A, 10B) Exhaust gas treatment device 11,21 Blower 12, 13, 22 Solenoid valves 14 Atmospheric gas supply source 15 Atmospheric gas inlet 16 Solenoid valve 17a~17d Solenoid valves 18 Secondary combustion section (afterburner furnace) 30 Gas circulation purification equipment 31 Adsorbents 32 Circulation Route 33 Blower 34 Solenoid valve

Claims

1. An apparatus for treating exhaust gas discharged from an atmosphere-controlled working space through a circulation path, an adsorber provided in the flow path, into which the exhaust gas is introduced, and containing an adsorbent that adsorbs toxic gases contained in the exhaust gas; an oxidation reactor that is provided in the flow path downstream of the adsorber, into which the exhaust gas discharged from the adsorber is introduced, and that contains a catalyst that oxidizes toxic gases contained in the exhaust gas; a catalyst heating unit that heats the catalyst; a control unit that controls the catalyst heating unit so as to heat the catalyst when the exhaust gas is discharged from the working space to the circulation path; An exhaust gas treatment device comprising:

2. further comprising an adsorbent heating unit that heats the adsorbent; The exhaust gas treatment device according to claim 1 , wherein the control unit further controls the adsorbent heating unit so as to heat the adsorbent when the temperature of the catalyst reaches a predetermined temperature.

3. the distribution path is provided to divide the exhaust gas discharged from the working space and introduce it into each of the plurality of adsorber devices, and to introduce the exhaust gas discharged from each of the adsorber devices into the oxidation reactor, an adsorbent heating unit that heats the adsorbent accommodated in the adsorbent is provided for each of the plurality of adsorbers; The exhaust gas treatment device according to claim 2 , wherein the control unit controls each of the one or more adsorbent heating units so as to switch between the one or more adsorbent heating units that heat the adsorbent.

4. The exhaust gas treatment device according to claim 1 , wherein the adsorbent adsorbs acidic gases contained in the toxic gases.

5. The exhaust gas treatment device according to claim 1 , further comprising an oxygen introducing section, provided in the flow path upstream of the oxidation reactor, for introducing a gas containing oxygen into the flow path.

6. The exhaust gas treatment device according to claim 1 , further comprising an exhaust gas heating unit that heats the exhaust gas, the exhaust gas heating unit being provided in the flow path upstream of the adsorber.

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