Organic solvent gas removal equipment

Abstract

To provide an organic solvent gas removal device for removing a volatile organic compound in an exhaust gas of a production facility with a high removal rate.SOLUTION: An organic solvent gas removal device divides an adsorption rotor having adsorption capability of an organic solvent gas into at least a treatment zone, a purge zone and a reproduction zone, passes a treated gas discharged from a production facility through the treatment zone, returns a part of the gas having passed through the treatment zone to a front side of the treatment zone, supplies a part of the remaining gas having passed through the treatment zone to a supply destination or emits the part of the remaining gas to the atmosphere, passes a part of outside air and / or the treated gas through the purge zone and then passes the part of the outside air and / or treated gas through a heating device, passes the gas having passed through the heating device through the reproduction zone, and supplies the gas having passed through the reproduction zone to a VOC purification device and a VOC recovery device or the like.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an organic solvent gas removal device, and more particularly to a device capable of removing volatile organic compounds (hereinafter referred to as VOCs) in exhaust gases from production facilities, etc., at a high removal rate. [Background technology]

[0002] Conventionally, in semiconductor and paint factories, it has been considered effective to purify the air by removing VOCs such as toluene and xylene from the exhaust gas from each production facility. Therefore, there is a demand for a high purification rate of harmful substances such as VOCs using organic solvent gas removal equipment.

[0003] Honeycomb rotor-type organic gas removal devices, which use a honeycomb body carrying an adsorbent, are suitable for removing a wide variety of VOCs and have come to be widely used industrially.

[0004] Patent Document 1 proposes a technique for increasing the concentration rate of VOCs by forming ceramic paper into a honeycomb shape and using a honeycomb rotor carrying hydrophobic zeolite on the ceramic paper. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2006-187698 A Summary of the Invention [Problem to be solved by the invention]

[0006] The system disclosed in Patent Document 1 can increase the concentration ratio by returning a portion of the regeneration outlet air to the regeneration inlet, but has the problem that it is difficult to achieve a high removal rate by simply passing the treated air through the treatment zone once.

[0007] In addition, the relatively high VOC concentration air at the treatment inlet is passed through a purge zone for cooling, which reduces the desorption efficiency.Furthermore, when the humidity of the air being treated is high, energy is used for desorption, which reduces the removal performance.

[0008] In view of this situation, the main object of the present invention is to provide an organic solvent gas removal device with a high removal rate by adopting a treatment circulation flow in which the air with a low VOC concentration that has passed through the treatment zone is returned to the inlet of the treatment zone. In addition, the VOC removal performance of the treatment zone is improved by passing the air with a low VOC concentration after passing through the treatment zone through a purge zone to be used as cooling air. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention divides an adsorption rotor capable of adsorbing organic solvent gas into at least a treatment zone, a purge zone, and a regeneration zone, and passes the gas to be treated discharged from a production process or the like through the treatment zone, a portion of the gas that has passed through the treatment zone is returned to the front of the treatment zone, a remaining portion of the gas that has passed through the treatment zone is sent to a supply destination or released into the atmosphere, and a portion of the outside air and / or the gas to be treated is passed through the purge zone and then through a heating device, the gas that has passed through the heating device is passed through the regeneration zone, and the gas that has passed through the regeneration zone is sent to a VOC purification device or a VOC recovery device, etc.

[0010] In addition, in the present invention, an adsorption rotor capable of adsorbing organic solvent gas is divided into at least a treatment zone, a purge zone, and a regeneration zone, and the gas to be treated discharged from a production process or the like is passed through the treatment zone, a portion of the gas that has passed through the treatment zone is passed through the purge zone and then through a heating device, the gas that has passed through the heating device is passed through the regeneration zone, the gas that has passed through the regeneration zone is sent to a VOC purification device or a VOC recovery device, etc., and a remaining portion of the gas that has passed through the treatment zone is sent to a supply destination or released into the atmosphere.

[0011] By using the above-mentioned organic solvent gas removal apparatus or by combining these flows, a high removal rate can be achieved. Effect of the Invention

[0012] By returning a portion of the purified gas at the treatment zone outlet to the treatment zone inlet, the VOC concentration at the treatment zone inlet can be reduced and the removal rate improved. Furthermore, by returning the heated treatment zone outlet gas to the treatment zone inlet, the relative humidity at the treatment zone inlet can be reduced, which is expected to improve the VOC adsorption efficiency. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a flow diagram of the organic solvent gas removal apparatus according to the first embodiment of the present invention. [Diagram 2] FIG. 2 is a flow diagram of the organic solvent gas removal apparatus according to the second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In the present invention, in an organic solvent gas removal apparatus, an adsorption rotor capable of adsorbing organic solvent gas is divided into at least a treatment zone, a purge zone, and a regeneration zone, the gas to be treated discharged from a production facility or the like is passed through the treatment zone, a portion of the gas that has passed through the treatment zone is returned to the front of the treatment zone, a remaining portion of the gas that has passed through the treatment zone is sent to a supply destination or released into the atmosphere, and a portion of the outside air and / or the gas to be treated is passed through the purge zone and then passed through a heating device, the gas that has passed through the heating device is passed through the regeneration zone, and the gas that has passed through the regeneration zone is sent to a VOC purification device, a VOC recovery device, or the like.

[0015] In addition, in the organic solvent gas removal apparatus of the present invention, an adsorption rotor capable of adsorbing organic solvent gas is divided into at least a treatment zone, a purge zone, and a regeneration zone, and the gas to be treated discharged from a production facility or the like is passed through the treatment zone, a portion of the gas that has passed through the treatment zone is passed through the purge zone and then through a heating device, the gas that has passed through the heating device is passed through the regeneration zone, the gas that has passed through the regeneration zone is sent to a VOC purification device or a VOC recovery device or the like, and a remaining portion of the gas that has passed through the treatment zone is sent to a supply destination or released into the atmosphere. EXAMPLES

[0016] A first embodiment of the organic solvent gas removal device will be described below with reference to the flow diagram in Fig. 1. The configuration of the present invention includes a VOC adsorption rotor 1, a treatment circuit 7, and a regeneration heater 9. The VOC adsorption rotor 1 is a honeycomb rotor made of a ceramic base material carrying a VOC adsorbent such as zeolite or activated carbon. The VOC adsorption rotor 1 is divided into a treatment zone 2, a regeneration zone 4, and a purge zone 3.

[0017] As shown in Figure 1, exhaust gas (gas to be treated) containing VOCs from a production facility or the like is sent through piping 5 to treatment zone 2 of the VOC adsorption rotor 1, where the VOCs are adsorbed. A portion of the gas that has passed through treatment zone 2 is returned to piping 5 through treatment circulation path 7 (which returns gas that has passed through treatment zone 2 to the front of treatment zone 2) and sent to treatment zone 2 together with the gas to be treated. The remaining portion of the gas that has passed through treatment zone 2 is released into the atmosphere as purified air. This purified air does not necessarily have to be released into the atmosphere, but may also be returned to the production facility as a supply destination.

[0018] The air OA and / or a portion of the gas to be treated is passed through a purge zone 3 and then through a regeneration heater 9, and the gas that has passed through the regeneration heater 9 is passed through a regeneration zone 4. The gas that has passed through the regeneration zone 4 is sent to a VOC purification device such as a VOC combustion device, a VOC oxidative decomposition device, or a VOC recovery device.

[0019] The first embodiment of the present invention is configured as described above, and will be described in detail below. Gas containing VOCs (gas to be treated) discharged from a production facility such as a semiconductor or paint factory is sent to the treatment zone 2, where the VOCs in the gas to be treated are adsorbed and removed by the VOC adsorbent. A part of the gas that has passed through the treatment zone 2 is returned to the pipe 5 through the treatment circulation path 7 and mixed with the gas to be treated. A part of the remaining gas that has passed through the treatment zone 2 is either released to the atmosphere outside the device or sent to a supply destination such as a production facility. By passing the atmosphere OA and / or a part of the gas to be treated through the purge zone 3, the VOC adsorbent of the VOC adsorption rotor 1, whose temperature has increased in the regeneration zone 4, is cooled, and the adsorption performance of the VOC adsorbent is restored. The gas that has passed through the purge zone 3 is sent to the regeneration heater 9, where it is heated to a temperature sufficient to desorb VOCs from the VOC adsorbent of the VOC adsorption rotor 1, and sent to the regeneration zone 4. The gas that has passed through the regeneration zone 4 is sent through a pipe 10 to a VOC purification device such as a VOC combustion device, a VOC oxidative decomposition device, or a VOC recovery device, or to a combustion facility such as a boiler for use as fuel.

[0020] In this way, in the organic solvent gas removal apparatus of the first embodiment, by returning a part of the purified air at the treatment outlet to the treatment inlet side, the VOC concentration at the rotor treatment inlet can be lowered, and the VOC concentration at the treatment outlet can be reduced. In the conventional flow in which a part of the air to be treated is passed through the purge zone, the VOC concentration at the treatment inlet is 500 mg / Nm3. 3 In this case, the VOC concentration at the treatment outlet is 18.6 mg / Nm 3 The removal rate is 96.3%, but in the flow of this Example 1, the VOC concentration at the treatment outlet is 17.0 mg / Nm 3 This results in a removal rate of 96.6%.

[0021] In addition, when the concentration of the gas to be treated in the organic solvent gas removal apparatus of Example 1 fluctuates, the range of fluctuation can be reduced by mixing the treated outlet gas, thereby reducing the range of fluctuation in the VOC concentration of the treated outlet gas discharged from the organic solvent gas removal apparatus. EXAMPLES

[0022] The organic solvent gas removal apparatus according to the second embodiment will be described below with reference to the flow chart of FIG. Although explanations of parts overlapping with Example 1 will be omitted, in Example 2, gas that has passed through treatment zone 2 in pipe 8 is used as the cooling air passed through purge zone 3, and the gas is flowed in the opposite direction to Example 1 (hereinafter referred to as "reverse purging"). On the other hand, if the air to be treated is used as the cooling air passed through purge zone 3, the VOC concentration will be relatively high, and if it is used as is for cooling air, this will hinder the desorption effect. Also, when humidity is high, energy is used for desorption, which reduces the VOC removal performance.

[0023] The second embodiment of the present invention is configured as described above, and will be described in detail below. Gas containing VOCs (gas to be treated) discharged from a production facility such as a semiconductor or paint factory is sent to the treatment zone 2, where the VOCs in the gas to be treated are adsorbed and removed by the VOC adsorbent. A part of the gas that has passed through the treatment zone 2 is sent to the purge zone 3 through the pipe 8. A part of the remaining gas that has passed through the treatment zone 2 is either released to the atmosphere outside the device or sent to a destination such as a production facility. The gas that has passed through the purge zone 3 is sent to the regeneration heater 9 through the pipe 11. By passing cooling air through the purge zone 3, the VOC adsorbent of the VOC adsorption rotor 1, whose temperature has increased in the regeneration zone 4, is cooled, and the adsorption performance of the VOC adsorbent is restored. The gas that has passed through the purge zone 3 is sent to the regeneration heater 9, where it is heated to a temperature sufficient to desorb VOCs from the VOC adsorbent of the VOC adsorption rotor 1, and sent to the regeneration zone 4. The gas that has passed through the regeneration zone 4 is sent through a pipe 10 to a VOC purification device such as a VOC combustion device, a VOC oxidative decomposition device, or a VOC recovery device, or to a combustion facility such as a boiler for use as fuel.

[0024] In the conventional flow where a portion of the treated air is passed through a purge zone, the VOC concentration at the treatment inlet is 500 mg / Nm 3 In this case, the VOC concentration at the treatment outlet is 18.6 mg / Nm 3 The removal rate is 96.3%, but in the flow of this Example 2, the VOC concentration at the treatment outlet is 16.5 mg / Nm 3 This results in a removal rate of 96.7%.

[0025] Although not shown, a flow using treatment circulation as in Example 1 may be combined with a flow using reverse purging as in Example 2. The regenerative heater 9 may be an electric heater, a gas heater, a heat exchanger, or a mixing chamber that mixes high-temperature combustion exhaust gas with the gas being treated. [Industrial Applicability]

[0026] The present invention provides an organic solvent gas removal device that can be used for exhaust from paint factories for automobiles, aircraft, ships, etc. that contain large amounts of VOCs in their exhaust gases, exhaust from semiconductor cleaning processes, exhaust from manufacturing processes for electrode plates used in lithium ion secondary batteries, and exhaust from manufacturing processes for magnetic recording media. [Explanation of symbols]

[0027] 1 VOC adsorption rotor 2 Treatment Zone 3 Purge Zone 4. Play Zone 5, 6, 8, 10, 11 Piping 7 Processing Circuit 9 Regenerative Heater

Claims

[Claim 1] an organic solvent gas removal system comprising an adsorption rotor capable of adsorbing organic solvent gas, the adsorption rotor being divided into at least a treatment zone, a purge zone, and a regeneration zone; a gas to be treated containing VOCs is passed through the treatment zone to adsorb the VOCs; a portion of the gas that has passed through the treatment zone is returned to the front of the treatment zone to be mixed with the gas to be treated and passed through the treatment zone; a portion of the mixed gas that has passed through the treatment zone is passed through the purge zone; a portion of the remaining mixed gas that has passed through the treatment zone is sent to a supply destination or is released into the atmosphere;

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