JP2018118221A - Gas treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas treatment device where treating load in a plasma treatment section is surely obtained and the treatment capacity of the plasma treatment section is rapidly conformed to proper treatment capacity corresponding to the treating load.SOLUTION: A gas treatment device has a mixing ratio applied voltage initial controlling unit 6. In the mixing ratio applied voltage initial controlling unit 6,; a mixing ratio M of a first gas G1 (treating object gas C) to a second gas G2 (treated gas E) and a voltage V applied between electrodes in the plasma treatment section 3 are controlled so that the capacity of the plasma treatment part 3 becomes a practical maximum treatment capacity (so that mixture ratio M becomes a practical upper limit mixing ratio Mmax and an applied voltage becomes a practical upper limit voltage Vmax) when starting the gas treatment device 100; and treating load in the plasma treatment section 3 is obtained from a difference Δh between first absolute humidity (absolute humidity of a mixing treating object gas D) hF and second absolute humidity (absolute humidity of the treated gas E) hR.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas processing apparatus that purifies a processing target gas.

  2. Description of the Related Art Conventionally, a technique for purifying exhaust gas by generating a plasma state by performing high voltage discharge in the exhaust gas is known. In recent years, this technology is being applied to a purification device for purifying factory exhaust and an air purifier for purifying indoor air for the purpose of deodorization.

  Plasma that is in a thermally non-equilibrium state, that is, in which the electron temperature is much higher than the temperature of the gas or ion (non-equilibrium plasma (hereinafter simply referred to as plasma)) is the ion or radical produced by electron collision. Promotes a chemical reaction that does not occur at room temperature, and is considered useful in hazardous gas treatment as a medium that can efficiently remove or decompose harmful gases. What is important in the practical application of this technology is to improve the energy efficiency during processing, and to convert it into a completely safe product after processing with plasma.

In general, plasma at atmospheric pressure is generated by gas discharge or electron beam. Currently considered for application are nitrogen oxides (NOx), sulfur oxides (SOx), chlorofluorocarbons, carbon dioxide (CO ₂ ) Volatile organic solvent (VOC). Above all, NOx is contained in the exhaust gas of a car, so that it needs to be put into practical use immediately.

  As a gas processing apparatus for purifying this kind of gas, a honeycomb structure having a large number of through holes is arranged in a ventilation path, and a high voltage is applied between electrodes arranged at both ends of the honeycomb structure, There is a type that generates plasma in the through hole. In this gas processing apparatus, the harmful gas contained in the gas to be processed that passes through the through holes is decomposed into harmless substances by the plasma generated in the through holes of the honeycomb structure (for example, Patent Document 1). reference).

  In this type of gas processing apparatus, a technique for generating uniform plasma as a whole in the honeycomb structure has not been established, and the gas processing capacity becomes unstable. On the other hand, the plasma generation state inside the honeycomb structure has a characteristic that it is performed more actively as the moisture in the gas to be processed increases, and is suppressed when the moisture is lower. That is, there is a characteristic that the gas processing capacity increases as the water content in the gas to be processed increases, and the gas processing capacity decreases as the water content decreases.

  Therefore, in Patent Document 2, moisture is sent to the space between the electrode and the honeycomb structure by a humidifier to increase the moisture concentration in the gas to be processed and activate the plasma discharge to increase the gas processing capacity. A gas processing apparatus is disclosed.

JP 2000-140562 A JP 2004-089708 A

  However, the technique disclosed in Patent Document 2 does not control the amount of moisture fed by the humidifier, so if the amount of moisture supplied is too small, the generation of plasma discharge is insufficient and the gas processing capacity is insufficient. There is a possibility that the by-product is generated without completely decomposing the treated substance. If the amount of water to be supplied is excessive, the gas processing capability is increased, but the discharge becomes intense, and there is a possibility that abnormal discharge such as spark discharge occurs. In addition, when the plasma-treated air is supplied to the room, the humidity of the air supplied to the room becomes high, which causes a problem that people in the room feel uncomfortable.

The present invention has been made to solve such a problem, and the object of the present invention is to provide a gas treatment capable of maintaining a constant humidity environment in the honeycomb structure and stabilizing the gas treatment capacity. To provide an apparatus.
It is another object of the present invention to provide a gas processing apparatus that does not cause uncomfortable feelings to a person in the room due to high humidity of air after plasma processing.
In addition, a gas processing apparatus capable of reliably obtaining the processing load in the plasma processing unit before stabilizing the gas processing and quickly adjusting the processing capacity of the plasma processing unit to an appropriate processing capacity corresponding to the processing load. Is to provide.

  In order to achieve such an object, the present invention is arranged in a ventilation path (A) in a gas processing device (100) configured to purify a processing target gas and output it as a processed gas. The water treatment unit (1) configured to humidify the flowing treatment target gas, and the treatment target gas provided at the downstream side of the ventilation path from the water treatment unit and humidified by the water treatment unit is the first gas. Mixing configured to adjust the humidity by mixing the first gas and the second gas with the gas to be treated or the gas that has been treated before being humidified by the water treatment unit as the second gas A honeycomb structure having a part (2) and a large number of through holes (31a) that are provided downstream of the mixing part and that pass through the gas to be processed whose humidity has been adjusted in the mixing part as the gas to be mixed Body (31), And electrodes (32, 33) disposed on the upstream side and the downstream side of the honeycomb structure with respect to the direction in which the gas to be mixed passes, and the honeycomb structure is penetrated by the voltage applied between the electrodes. A plasma processing unit (3) configured to generate plasma in the hole, and a first configured to measure the absolute humidity of the gas to be mixed toward the plasma processing unit from the mixing unit as the first absolute humidity. The second humidity configured to measure the absolute humidity of the processed gas as the second absolute humidity, with the humidity measurement unit (S1) and the mixed processing target gas that has passed through the plasma processing unit as the processed gas A measurement unit (S2) and a mixing ratio control unit (7) configured to control the mixing ratio of the first gas and the second gas in the mixing unit so that the first absolute humidity becomes a target value. And the first absolute An applied voltage control unit (8) configured to control a voltage applied between the electrodes of the plasma processing unit so that a difference between the humidity and the second absolute humidity falls within a predetermined humidity difference range; Before the control of the mixing ratio by the ratio control unit and the control of the voltage applied between the electrodes of the plasma processing unit by the applied voltage control unit are started, the capability of the plasma processing unit is set to the practical maximum processing capability. And a mixing ratio applied voltage initial control unit (6) configured to control a mixing ratio between the first gas and the second gas and a voltage applied between electrodes of the plasma processing unit. .

  In the present invention, the first humidity measuring unit measures the absolute humidity of the gas to be mixed from the mixing unit toward the plasma processing unit as the first absolute humidity (hF), and the second humidity control unit is configured to perform the plasma processing. The absolute humidity of the mixed processing target gas (processed gas) that has passed through the section is measured as the second absolute humidity (hR). The mixing ratio control unit includes a first gas (processing target gas humidified by the water treatment unit) and a second gas (water treatment unit) such that the first absolute humidity (hF) becomes the target value (hsp). To control the mixing ratio (M) with the gas to be treated or gas before being humidified. Thereby, the absolute humidity (hF) of the gas to be mixed from the mixing section toward the plasma processing section is set to the target value (hsp), and the gas to be mixed having the absolute humidity (hF) set to the target value (hsp) It is sent to the plasma processing unit.

On the other hand, the applied voltage control unit causes the difference (Δh = hF−hR) between the first absolute humidity (hF) and the second absolute humidity (hR) to fall within a predetermined humidity difference range (ΔhB ± α). In addition, the voltage (V) applied between the electrodes of the plasma processing unit is controlled.
For example, when the difference (Δh) between the first absolute humidity (hF) and the second absolute humidity (hR) is large and out of a predetermined humidity difference range (Δh> ΔhB + α), mixing in the plasma processing unit The voltage (V) applied between the electrodes of the plasma processing unit is controlled so as to suppress the gas processing capacity for the processing target gas. When the gas processing capacity is suppressed, the water consumption in the plasma processing unit is reduced, the second absolute humidity (hR) is increased, and the first absolute humidity (hF) and the second absolute humidity (hR) are increased. So that the difference (Δh) between the first absolute humidity (hF) and the second absolute humidity (hR) falls within a predetermined humidity difference range (ΔhB ± α). Become.
For example, when the difference (Δh) between the first absolute humidity (hF) and the second absolute humidity (hR) is small and outside a predetermined humidity difference range (Δh <ΔhB−α), The voltage (V) applied between the electrodes of the plasma processing unit is controlled so as to increase the gas processing capacity for the gas to be mixed. When the gas processing capacity is increased, the amount of water consumption in the plasma processing unit increases, the second absolute humidity (hR) decreases, and the first absolute humidity (hF) and the second absolute humidity (hR) And the difference (Δh) between the first absolute humidity (hF) and the second absolute humidity (hR) falls within a predetermined humidity difference range (ΔhB ± α). .

  Thus, in the present invention, the mixing ratio (M) of the first gas and the second gas is controlled so that the first absolute humidity (hF) becomes the target value (hsp), and the first Voltage (V) applied between the electrodes of the plasma processing unit so that the difference (Δh) between the absolute humidity (hF) and the second absolute humidity (hR) falls within a predetermined humidity difference range (ΔhB ± α). Is controlled. Thereby, the humidity environment in the honeycomb structure is kept constant, and the gas processing capacity is stabilized. In addition, there is no problem that the humidity of the air after the plasma treatment becomes high and makes people in the room feel uncomfortable.

  Further, in the present invention, the mixing ratio applied voltage initial control unit is configured to start the control of the mixing ratio by the mixing ratio control unit and the control of the voltage applied between the electrodes of the plasma processing unit by the applied voltage control unit. The mixing ratio of the first gas and the second gas and the voltage applied between the electrodes of the plasma processing unit are controlled so that the capability of the plasma processing unit becomes the practical maximum processing capability. Accordingly, it is possible to reliably determine the processing load of the plasma processing unit before stabilizing the gas processing, and quickly adjust the processing capability of the plasma processing unit to an appropriate processing capability corresponding to the processing load.

  In the above description, as an example, constituent elements on the drawing corresponding to the constituent elements of the invention are indicated by reference numerals with parentheses.

  As described above, according to the present invention, the mixing ratio of the first gas and the second gas in the mixing unit is controlled so that the first absolute humidity becomes the target value, and the first absolute humidity and Since the voltage applied between the electrodes of the plasma processing unit is controlled so that the difference from the second absolute humidity falls within a predetermined humidity difference range, the humidity environment in the honeycomb structure is kept constant, It becomes possible to stabilize the processing capacity. In addition, there is no problem that the humidity of the air after the plasma treatment becomes high and makes people in the room feel uncomfortable.

  Further, according to the present invention, before the control of the mixing ratio by the mixing ratio control unit and the control of the voltage applied between the electrodes of the plasma processing unit by the applied voltage control unit are started, the capability of the plasma processing unit is practically used. Since the mixing ratio of the first gas and the second gas and the voltage applied between the electrodes of the plasma processing unit are controlled so as to obtain the maximum processing capacity, before the gas processing is stabilized, It is possible to reliably determine the processing load in the plasma processing unit and quickly adjust the processing capability of the plasma processing unit to an appropriate processing capability corresponding to the processing load.

FIG. 1 is a diagram showing a main part of a gas processing apparatus according to an embodiment of the present invention. FIG. 2 is a schematic view showing the configuration of the scrubber unit in this gas processing apparatus. FIG. 3 is a schematic diagram showing the configuration of the plasma processing unit in this gas processing apparatus. FIG. 4 is a diagram showing an outline of the hardware configuration of the control device in this gas processing apparatus. FIG. 5 is a flowchart for explaining a processing operation (a processing operation performed by the mixing ratio applied voltage initial control unit) executed by the CPU of the control device. FIG. 6 is a flowchart for explaining the processing operation (processing operation performed by the mixing control unit) executed by the CPU of the control device. FIG. 7 is a flowchart for explaining the processing operation (processing operation performed by the applied voltage control unit) executed by the CPU of the control device. FIG. 8 is a flowchart for explaining a processing operation (a processing operation performed by the mixture ratio applied voltage changing unit) executed by the CPU of the control device. FIG. 9 is a diagram showing the relationship between the mixing ratio M and the applied voltage V. In FIG. FIG. 10 is a diagram illustrating a state in which the processing capability of the plasma processing unit is adjusted to a point Z of an appropriate processing capability corresponding to the processing load. FIG. 11A is a diagram showing a state (Δh> ΔhB + α) where the difference Δh between the first absolute humidity hF and the second absolute humidity hR is large and is out of the reference humidity difference range ΔhB ± α. FIG. 11B is a diagram showing a state where the difference Δh between the first absolute humidity hF and the second absolute humidity hR is in the reference humidity difference range ΔhB ± α. FIG. 12A is a diagram illustrating a state where the difference Δh between the first absolute humidity hF and the second absolute humidity hR is small and outside the reference humidity difference range ΔhB ± α (Δh <ΔhB−α). FIG. 12B is a diagram illustrating a state where the difference Δh between the first absolute humidity hF and the second absolute humidity hR is in the reference humidity difference range ΔhB ± α. FIG. 13 shows the current operating point Z while maintaining the current processing capability of the plasma processing unit, the specified practical upper limit mixing ratio Mmax and the changed applied voltage Vx (changed value in the direction of the practical lower limit voltage Vmin). It is a figure which shows the state made to transfer to the point ZA prescribed | regulated by. FIG. 14 shows the current operating point Z while maintaining the current processing capability of the plasma processing unit, the specified practical lower limit mixing ratio Mmin and the applied voltage Vx after the change (changed value in the direction of the practical upper limit voltage Vmax). It is a figure which shows the state made to transfer to the operation point ZB prescribed | regulated by. FIG. 15 shows the current operating point Z while maintaining the current processing capability of the plasma processing unit and the specified practical lower limit voltage Vmin and the changed mixture ratio Vx (changed value in the direction of the practical upper limit mixture ratio Mmax). It is a figure which shows the state made to transfer to the point ZC prescribed | regulated by. FIG. 16 defines the current operating point Z with the specified practical upper limit voltage Vmax and the mixture ratio Mx (change value in the direction of the practical lower limit mixture ratio Mmin) while maintaining the current processing capability of the plasma processing unit. It is a figure which shows the state made to transfer to the point ZD made. FIG. 17 is a functional block diagram of the main part of the mixing control unit. FIG. 18 is a functional block diagram of the main part of the applied voltage control unit. FIG. 19 is a functional block diagram of a main part of the mixing ratio applied voltage changing unit. FIG. 20 is a diagram illustrating an example in which the gas to be processed before being humidified by the scrubber unit is supplied to the mixing unit as the second gas.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a view showing a main part of a gas processing apparatus 100 according to an embodiment of the present invention.

  The gas processing apparatus 100 includes a scrubber unit (water processing unit) 1, a mixing unit (mixing unit) 2, a plasma processing unit 3, and a flow rate of the processed gas E supplied to the mixing unit 2. And a control device 4 for controlling a voltage (hereinafter also referred to as an applied voltage) V applied between the electrodes of the plasma processing unit 3.

  In the gas processing apparatus 100, a duct A1 is connected to the ventilation path A. The duct A <b> 1 is a duct extending from the downstream side of the plasma processing unit 3 to the mixing unit 2, and plays a role of returning a part of the processed gas E to the mixing unit 2. The duct A1 is provided with an air supply valve 5 for adjusting the flow rate of the processed gas E returned to the mixing unit 2.

  In the gas processing apparatus 100, the scrubber unit 1 humidifies the processing target gas B flowing through the ventilation path A. The mixing unit 2 is provided on the downstream side of the ventilation path A with respect to the scrubber unit 1. The processing target gas C humidified by the scrubber unit 1 is the first gas G1, and the processed gas E through the duct A1 is the second gas. The humidity is adjusted by mixing the first gas G1 and the second gas G2 with the gas G2. The plasma processing unit 3 is provided on the downstream side of the ventilation path A with respect to the mixing unit 2 and inputs the processing target gas whose humidity has been adjusted in the mixing unit 2 as the mixing processing target gas D, and this input mixing processing The target gas D is purified to a treated gas E.

  Further, in the gas processing apparatus 100, the absolute humidity of the mixed processing target gas D from the mixing unit 2 toward the plasma processing unit 3 is set to the first absolute value in the ventilation path A between the mixing unit 2 and the plasma processing unit 3. A humidity sensor S1 that measures the humidity hF is provided. In addition, a humidity sensor S2 that measures the absolute humidity of the treated gas E that has passed through the plasma processing unit 3 as the second absolute humidity hR is provided in the ventilation path A on the downstream side of the plasma processing unit 3.

The toxic gas contained in the gas B to be treated includes nitrogen oxide (NOx), sulfur oxide (SOx), chlorofluorocarbon, carbon dioxide (CO ₂ ). Volatile organic solvent (VOC). In addition, the dust contained in the processing target gas B includes inorganic dust such as metal powder and rock powder, and organic dust such as cotton dust. In the present invention, soot generated due to combustion of objects, exhaust gas from automobiles, etc. Particulate matter contained in the gas is also included in the dust.

  FIG. 2 is a schematic view showing the configuration of the scrubber unit 1 in the gas processing apparatus 100. As shown in FIG. 2, the inside of the tank 11 of the scrubber unit 1 is partitioned by a partition plate 12 into two spaces 13-1 and 13-2 in a state where the lower part communicates. In one space 13-1, the filler 14 is supported by the inner wall 11 a of the tank 11 and the partition plate 12, and the spraying unit 15 that sprays water in a mist toward the filler 14 above the filler 14. Is provided.

  Further, the tank 11 at a position above the spraying unit 15 is provided with an exhaust port 16 for exhausting the processing target gas C having passed through the filler 14 and having a relative humidity of 100% to the ventilation path A. In addition, the tank 11 that forms the other space 13-2 with respect to the space 13-1 in which the filler 14 is supported is provided with an intake port 17 that is connected to the ventilation path A and sucks the processing target gas B. ing. Moreover, the filler 14 is comprised by resin, such as polyester and polypropylene processed into the fiber form, and the space | gap is formed between fibrous resins.

  A water tank 18 that stores water is provided at the bottom of the tank 11, and a pump 19 that pumps water from the water tank 18 to the spraying unit 15 is provided for the water tank 18. A drain hose 20 is connected to the bottom surface of the water tank 18, and a drain valve 21 is provided on the drain hose 20. The tank 11 is provided with a water supply port 22, and a water supply hose 23 is connected to the water supply port 22.

  The water stored in the water tank 18 is used as circulating water, pumped up by the pump 19 and sprayed by the spraying unit 15. When it is necessary to replace the circulating water due to dirt or the like, the drain valve 21 is opened to drain water from the drain hose 20, and new water is supplied from the water inlet 22 to which the water hose 23 is connected.

  In the scrubber unit 1 configured in this way, the processing target gas B fed into the tank 11 from the intake port 17 is sprayed from the spraying unit 15 when rising through the gap in the filler 14. In contact with water and gas-liquid. In the present embodiment, the processing target gas B is brought into gas-liquid contact with water, so that the relative humidity of the processing target gas B that has flowed is set to 100%. The processing target gas C having a relative humidity of 100% is exhausted from the exhaust port 16 of the scrubber unit 1.

  The mixing unit 2 uses the processing target gas C having a relative humidity of 100% sucked from the scrubber unit 1 side as the first gas G1, the processed gas E through the duct A1 as the second gas G2, and the first gas. By mixing G1 and the second gas G2, a gas D to be mixed whose humidity is adjusted is produced.

  In the mixing unit 2, the processed gas E supplied as the second gas G2 has a lower humidity than the mixed processing target gas D. That is, the water concentration of the mixed processing target gas D is consumed by the plasma processing unit 3, so that the water concentration in the processed gas E is lower than the water concentration of the mixed processing target gas D. The mixing unit 2 mixes the processed gas E having a lower humidity than the mixed processing target gas D and the processing target gas C having a relative humidity of 100%. In this case, the humidity of the mixing target gas D is determined by the mixing ratio M (M = G1 / G2) of the first gas G1 and the second gas G2. The mixing control unit 7 in the control device 4 controls the mixing ratio M. Control of the mixing ratio M by the mixing controller 7 will be described later.

  FIG. 3 is a schematic diagram showing the configuration of the plasma processing unit 3 in the gas processing apparatus 100. As shown in FIG. 3, the plasma processing unit 3 includes a honeycomb structure 31 through which the gas D to be mixed passes, a first electrode 32 disposed on the upstream side of the honeycomb structure 31, and a honeycomb structure 31. And a high voltage power source 34 for applying a high voltage between the first electrode 32 and the second electrode 33.

  The honeycomb structure 31 has a large number of through-holes 31a formed in a honeycomb shape in a direction in which the gas to be mixed D flowing through the ventilation path A is passed, and is made of ceramic or the like. The first electrode 32 is connected to the positive electrode of the high voltage power supply 34 through a conducting wire, and is made of a metal mesh or the like. The second electrode 33 is connected to the negative pole of the high voltage power supply 34 via a conducting wire, and is made of a metal mesh or the like. The mesh shape of the first electrode 32 and the second electrode 33 is coarser than the through-hole 31 a formed in the honeycomb structure 31. The high voltage power supply 34 applies a high voltage of several kV to several tens of kV as the voltage V between the first electrode 32 and the second electrode 33.

  In the plasma processing unit 3, when a high voltage is applied between the first electrode 32 and the second electrode 33, plasma is generated inside the through hole 31 a of the honeycomb structure 31. Thereby, the harmful gas contained in the gas D to be mixed is decomposed into harmless substances by ions and radicals generated in the plasma. Further, dust contained in the gas D to be mixed is charged and attached to the first electrode 32 and the second electrode 33 and is removed by adsorption. The gas processed by the plasma processing unit 3 is exhausted downstream of the ventilation path A as the processed gas E.

  In this gas processing apparatus 100, the control device 4 includes a mixing ratio applied voltage initial control unit 6, a mixing control unit 7, an applied voltage control unit 8, and a mixing ratio applied voltage changing unit 9. Further, a mixing ratio applied voltage change value designating unit 10 is provided for the control device 4. FIG. 4 shows an outline of the hardware configuration of the control device 4.

  The control device 4 includes a central processing unit (CPU) 4-1, a random access memory (RAM) 4-2, a read only memory (ROM) 4-3, interfaces 4-4 and 4-5, and Are connected to the bus 4-6. In addition, a mixing ratio applied voltage control program is installed in the control device 4 as a program unique to the present embodiment.

  The CPU 4-1 operates according to the mixture ratio applied voltage control program installed in the control device 4 while accessing the RAM 4-2 and the ROM 4-3 by processing information input via the interface 4-4. To do. In this control device 4, the mixing ratio applied voltage initial control unit 6, the mixing control unit 7, the applied voltage control unit 8, and the mixing ratio applied voltage changing unit 9 are realized as processing functions of the CPU 4-1.

  Hereinafter, the processing operation of the CPU 4-1 in accordance with this mixture ratio application voltage control program will be described with reference to the flowcharts shown in FIGS. Here, the mixing ratio applied voltage initial control unit 6 performs the processing operation according to the flowchart shown in FIG. 5, the mixing control unit 7 performs the processing operation according to the flowchart shown in FIG. 6, and the applied voltage control unit 8 performs the processing operation according to the flowchart shown in FIG. The processing operation according to the flowchart shown will be described on the assumption that the mixing ratio applied voltage changing unit 9 performs the processing operation according to the flowchart shown in FIG.

[Initial control of mixing ratio and applied voltage]
When the gas processing apparatus 100 is started, the mixing ratio application voltage initial control unit 6 controls the mixing ratio M by a mixing control unit 7 described later and the voltage V applied between the electrodes of the plasma processing unit 3 by the applied voltage control unit 8. Before the start of the control, the mixing ratio M of the first gas G1 and the second gas G2 in the mixing unit 2 and the plasma processing so that the gas processing capability of the plasma processing unit 3 becomes the practical maximum processing capability. The voltage V applied between the electrodes of the unit 3 is controlled (FIG. 5: Steps S101 and S102).

  FIG. 9 shows the relationship between the mixing ratio M and the applied voltage V. In the figure, the vertical axis represents the applied voltage V, and the horizontal axis represents the mixing ratio M. In the present embodiment, the mixing ratio M is expressed as M = G1 / G2, and as the mixing ratio M increases, the moisture concentration in the mixing process target gas D increases, and as the mixing ratio M decreases, the mixing process target gas D increases. The moisture concentration of is low. That is, as the mixing ratio M increases, the humidity of the mixing process target gas D increases, and as the mixing ratio M decreases, the humidity of the mixing process target gas D decreases.

  The gas processing capacity of the plasma processing unit 3 is determined by the product of the magnitude of the applied voltage V and the mixing ratio M. However, a range where both the applied voltage V and the mixing ratio M can be controlled is determined. That is, the upper limit value of the applied voltage V at which spark discharge (abnormal discharge) does not occur in the plasma processing unit 3 is set as the practical upper limit voltage Vmax, and the lower limit value of the applied voltage at which the plasma processing unit 3 can generate plasma is set. When the practical lower limit voltage Vmin is set, the controllable range of the applied voltage V is determined as Vmin ≦ V ≦ Vmax. Further, the mixing ratio M corresponding to the allowable upper limit value of the first absolute humidity hF (the limit value of humidity that does not impair indoor comfort) is set to the practical upper limit mixing ratio Mmax, and plasma generated due to insufficient moisture in the plasma processing unit 3 When the mixing ratio M corresponding to the lower limit value of the first absolute humidity hF at which no by-product is generated from the mixing target gas D is the practical lower limit mixing ratio Mmin, the controllable range of the mixing ratio M is Mmin. It is defined as ≦ M ≦ Mmax.

  Therefore, the practical gas processing capacity of the plasma processing unit 3 is minimized at the point X (Mmin, Vmin) where the applied voltage V is the practical lower limit voltage Vmin and the mixing ratio M is the practical lower limit mixing ratio Mmin. Is the maximum at the point Y (Mmax, Vmax) where the practical upper limit voltage Vmax and the mixing ratio M are the practical upper limit mixing ratio Mmax.

  When the gas processing apparatus 100 is started, the mixing ratio applied voltage initial control unit 6 adjusts the opening θ of the air supply valve 5 so that the mixing ratio M in the mixing unit 2 becomes the practical upper limit mixing ratio Mmax (step S101). . Further, the voltage V between the electrodes of the plasma processing unit 3 is set to the practical upper limit voltage Vmax (step S102). Thereby, before the mixing control unit 7 and the applied voltage control unit 8 start a control operation described later, the gas processing capacity of the plasma processing unit 3 is set to the practical maximum processing capacity (Mmax, Vmax).

(Control of mixing ratio)
When the mixing control unit 7 receives notification from the applied voltage control unit 8 that calculation of the processing load in the plasma processing unit 3 to be described later has been completed (YES in step S201), the first absolute sensor measured by the humidity sensor S1 Humidity hF is captured (step S202), a preset target value hsp is read (step S203), and the captured first absolute humidity hF is compared with the read target value hsp (step S204).

  If the first absolute humidity hF does not match the target value hsp (NO in step S204), the mixing control unit 7 supplies air so that the first absolute humidity hF matches the target value hsp. The opening degree θ of the valve 5 is adjusted (step S205). In other words, the mixing control unit 7 adjusts the flow rate of the processed gas E supplied to the mixing unit 2 to adjust the first absolute humidity hF and the target value hsp so that the first absolute humidity hF matches the first value hsp. The mixing ratio M of the gas G1 and the second gas G2 is adjusted (controlled).

  In this embodiment, the mixing ratio M of the first gas G1 and the second gas G2 is adjusted so that the relative humidity of the mixing target gas D is about 90% by setting the target value hsp. As a result, the mixed processing target gas D having a relative humidity of about 90% is sent to the plasma processing unit 3.

  Here, about 90%, which is set as the relative humidity of the gas D to be mixed, is a moisture amount sufficient to generate plasma discharge and a moisture amount that suppresses occurrence of abnormal discharge such as spark discharge. In this example, the relative humidity of the gas D to be mixed is about 90%, but this is only an example. If the amount of water is sufficient to generate plasma discharge and the amount of water is sufficient to suppress the occurrence of abnormal discharge such as spark discharge, the relative humidity set value of the gas D to be mixed, that is, the first absolute humidity hF The set target value hsp can be changed as appropriate.

[Control of applied voltage]
When the gas processing capacity of the plasma processing unit 3 is set to the practical maximum processing capacity by the mixing ratio applied voltage initial control unit 6 (FIG. 7: YES in step S301), the applied voltage control unit 8 performs measurement by the humidity sensor S1. The first absolute humidity hF and the second absolute humidity hR measured by the humidity sensor S2 are fetched (step S302), and the difference Δh (Δh = hF−) between the fetched first absolute humidity hF and the second absolute humidity hR. hR) is calculated (step S303). Then, the applied voltage control unit 8 obtains a processing load in the plasma processing unit 3 from the difference Δh between the first absolute humidity hF and the second absolute humidity hR (step S304).

  In the processing operation shown in FIG. 6, the mixing control unit 7 waits for calculation of the processing load in the applied voltage control unit 8 (FIG. 6: YES in step S201), and then the first absolute humidity hF and the target value hsp. Is adjusted (controlled) so that the relative humidity of the gas D to be mixed is about 90%.

  The applied voltage control unit 8 has a processing capability corresponding to the processing load calculated in step S304 in a state where the mixing ratio M is adjusted so that the first absolute humidity hF matches the target value hsp. The voltage V applied between the electrodes of the plasma processing unit 3 is adjusted (step S305). As a result, the gas processing capacity of the plasma processing unit 3 that has been regarded as the practical maximum processing capacity is narrowed down, and approaches an appropriate gas processing capacity corresponding to the processing load.

  The applied voltage control unit 8 sets the first absolute humidity hF measured by the humidity sensor S1 and the second absolute humidity hR measured by the humidity sensor S2 in a state approaching an appropriate gas processing capacity corresponding to this processing load. Taking in (step S306), the difference Δh (Δh = hF−hR) between the taken-in first absolute humidity hF and second absolute humidity hR is calculated (step S307).

  Then, the applied voltage control unit 8 reads a reference humidity difference range ΔhB ± α set in advance as a predetermined temperature difference range (step S308), and calculates the first absolute humidity hF and the second absolute humidity hR. The voltage V applied between the electrodes of the plasma processing unit 3 is adjusted (controlled) so that the difference Δh falls within the reference humidity difference range ΔhB ± α (steps S309 to S312).

  That is, as shown in FIG. 11A, when the difference Δh between the first absolute humidity hF and the second absolute humidity hR is large and is out of the reference humidity difference range ΔhB ± α (Δh> ΔhB + α, YES in step S309) ) The applied voltage control unit 8 lowers the voltage V applied between the electrodes of the plasma processing unit 3 (step S310).

  Thereby, the gas processing capability with respect to the mixed processing target gas D in the plasma processing unit 3 is suppressed, the amount of water consumption in the plasma processing unit 3 is reduced, the second absolute humidity hR is increased, and the first absolute humidity hF. The difference Δh between the first absolute humidity hR and the second absolute humidity hR becomes small, and the difference Δh between the first absolute humidity hF and the second absolute humidity hR falls within the reference humidity difference range ΔhB ± α (see FIG. 11B). ).

  As shown in FIG. 12A, when the difference Δh between the first absolute humidity hF and the second absolute humidity hR is small and outside the reference humidity difference range ΔhB ± α (Δh <ΔhB−α, step S311). YES), the applied voltage control unit 8 increases the voltage V applied between the electrodes of the plasma processing unit 3 (step S312).

  Thereby, the gas processing capability with respect to the mixed processing target gas D in the plasma processing unit 3 is increased, the amount of water consumption in the plasma processing unit 3 is increased, the second absolute humidity hR is decreased, and the first absolute humidity hF and The difference Δh from the second absolute humidity hR becomes large, and the difference Δh between the first absolute humidity hF and the second absolute humidity hR falls within the reference humidity difference range ΔhB ± α (see FIG. 12B). .

  Thus, in the present embodiment, the mixing ratio M of the first gas G1 and the second gas G2 is adjusted (controlled) so that the first absolute humidity hF becomes the target value hsp, and the first The voltage V applied between the electrodes of the plasma processing unit 3 is adjusted (controlled) so that the difference Δh between the absolute humidity hF and the second absolute humidity hR falls within the reference humidity difference range ΔhB ± α.

  FIG. 10 shows a state in which the processing capability of the plasma processing unit 3 is adjusted to a point Z (MR, VR) of an appropriate processing capability corresponding to the processing load. MR is the adjusted mixing ratio M, and VR is the adjusted applied voltage V. Below, this point Z is also called an operation point.

  Thereby, in this Embodiment, the humidity environment in the honeycomb structure 31 is kept constant, and stabilization of gas processing capability is achieved. In addition, when the air after plasma treatment is supplied into the room, the humidity of the air after the plasma treatment is not increased and the person in the room does not feel uncomfortable.

  In the present embodiment, first, the processing load of the plasma processing unit 3 is obtained by setting the processing capability of the plasma processing unit 3 to the practical maximum processing capability (Mmax, Vmax), and the processing capability corresponding to this processing load is obtained. Since the voltage V applied between the electrodes of the plasma processing unit 3 is adjusted, the processing capability of the plasma processing unit 3 can be quickly adjusted to a point Z (MR, VR) of an appropriate processing capability corresponding to the processing load. Can be combined. In addition, since the processing capacity of the plasma processing unit 3 is initially set to the practical maximum processing capacity (Mmax, Vmax), there is no case where the processing load of the plasma processing unit 3 cannot be obtained due to insufficient capacity. As a result, the processing load of the plasma processing unit 3 can be reliably obtained before the gas processing capacity is stabilized.

[Change of mixing ratio and applied voltage]
[Example 1]
The mixing ratio applied voltage changing unit 9 designates the mixing ratio applied voltage change value in a state where the processing capability of the plasma processing unit 3 is adjusted to a point Z (MR, VR) of an appropriate processing capability corresponding to the processing load. When the practical upper limit mixture ratio Mmax is designated as the change value (changed value) of the mixing ratio M by the unit 10 (FIG. 8: YES in step S401), the current processing capability exhibited by the plasma processing unit 3 Is obtained as a change value (value after change) of the application voltage V (step S402).

  In this case, since the mixing ratio applied voltage changing unit 9 is required to maintain the current processing capability exhibited by the plasma processing unit 3, the applied voltage Vx as a changed value in the direction of the practical lower limit voltage Vmin. Ask for.

  Then, the mixing ratio applied voltage changing unit 9 sends the practical upper limit mixing ratio Mmax specified as the changed value of the mixing ratio M by the mixing ratio applied voltage changing value specifying unit 10 to the mixing control unit 7, and the mixing control unit 7 controls The mixing ratio M to be changed is changed to the practical upper limit mixing ratio Mmax (step S403). Further, the applied voltage Vx obtained as the change value of the applied voltage V is sent to the applied voltage control unit 8, and the voltage V applied between the electrodes of the plasma processing unit 3 is changed to Vx (step S403).

  In FIG. 13, while maintaining the current processing capability of the plasma processing unit 3, the current operating point Z (MR, VR) is changed to the practical upper limit mixing ratio Mmax (specified change value) and the applied voltage Vx (practical lower limit voltage Vmin). In this case, the operation point ZA (Mmax, Vmin) defined by the change value calculated in the direction of As can be seen from this figure, in Example 1, the voltage V applied between the electrodes of the plasma processing unit 3 is lowered, and energy saving control is realized while emphasizing the gas processing capability.

[Example 2]
The mixing ratio applied voltage changing unit 9 designates the mixing ratio applied voltage change value in a state where the processing capability of the plasma processing unit 3 is adjusted to a point Z (MR, VR) of an appropriate processing capability corresponding to the processing load. When the practical lower limit mixing ratio Mmin is designated as the change value (the value after change) of the mixing ratio M by the unit 10 (FIG. 8: YES in step SS401), the current processing capability exhibited by the plasma processing unit 3 Is obtained as a change value (value after change) of the application voltage V (step S402).

  In this case, since the mixing ratio applied voltage changing unit 9 is required to maintain the current processing capability exhibited by the plasma processing unit 3, the applied voltage Vx as a changed value in the direction of the practical upper limit voltage Vmax. Ask for.

  Then, the mixing ratio applied voltage changing unit 9 sends the practical lower limit mixing ratio Mmin specified as the changed value of the mixing ratio M by the mixing ratio applied voltage changing value specifying unit 10 to the mixing control unit 7, and the mixing control unit 7 controls The mixing ratio M to be changed is changed to the practical lower limit mixing ratio Mmin (step S403). Further, the applied voltage Vx obtained as the change value of the applied voltage V is sent to the applied voltage control unit 8, and the voltage V applied between the electrodes of the plasma processing unit 3 is changed to Vx (step S403).

  FIG. 14 shows that the current operating point Z (MR, VR) is changed to the practical lower limit mixing ratio Mmin (specified change value) and the applied voltage Vx (practical upper limit voltage Vmax while maintaining the current processing capability of the plasma processing unit 3. A change value calculated in the direction of) is shown in a state where the movement point ZB (Mmin, Vx) is defined. As can be seen from this figure, in Example 2, the mixing ratio M controlled by the mixing control unit 7 is lowered (the humidity of the gas D to be mixed is reduced), and the humidity reduction control is performed while placing importance on the gas processing capacity. It will be realized.

[Example 3]
The mixing ratio applied voltage changing unit 9 designates the mixing ratio applied voltage change value in a state where the processing capability of the plasma processing unit 3 is adjusted to a point Z (MR, VR) of an appropriate processing capability corresponding to the processing load. When, for example, the practical lower limit voltage Vmin is designated as the change value (value after change) of the applied voltage V by the unit 10 (FIG. 8: YES in step S404), the current processing capability exhibited by the plasma processing unit 3 is displayed. The mixing ratio Mx that can be maintained is obtained as a change value (value after change) of the mixture ratio M (step S405).

  In this case, the mixing ratio applied voltage changing unit 9 is required to maintain the current processing capability exhibited by the plasma processing unit 3, so that the mixing ratio is changed as a change value in the direction of the practical upper limit mixing ratio Mmax. Obtain Mx.

  Then, the mixing ratio applied voltage changing unit 9 sends the practical lower limit voltage Vmin specified as the changed value of the applied voltage V by the mixed ratio applied voltage changing value specifying unit 10 to the applied voltage control unit 8, and the electrode of the plasma processing unit 3 The voltage V applied between them is changed to the practical lower limit voltage Vmin (step S406). Further, the mixing ratio Mx obtained as the change value of the mixing ratio M is sent to the mixing control unit 7, and the mixing ratio M controlled by the mixing control unit 7 is changed to Mx (step S406).

  FIG. 15 shows that the current operation point Z (MR, VR) is changed to the practical lower limit voltage Vmin (specified change value) and the mixture ratio Vx (practical upper limit mixture ratio Mmax) while maintaining the current processing capability of the plasma processing unit 3. A change value calculated in the direction of) is shown in a state where the operation point ZC (Mx, Vmin) is defined. As can be seen from this figure, in Example 3, the voltage V applied between the electrodes of the plasma processing unit 3 is lowered, and energy saving control is realized while emphasizing the gas processing capability.

[Example 4]
The mixing ratio applied voltage changing unit 9 designates the mixing ratio applied voltage change value in a state where the processing capability of the plasma processing unit 3 is adjusted to a point Z (MR, VR) of an appropriate processing capability corresponding to the processing load. When, for example, a practical upper limit voltage Vmax is designated as a change value (value after change) of the applied voltage V by the unit 10 (FIG. 8: YES in step S404), the current processing capability exhibited by the plasma processing unit 3 is displayed. The mixing ratio Mx that can be maintained is obtained as a change value (value after change) of the mixture ratio M (step S405).

  In this case, the mixing ratio applied voltage changing unit 9 is required to maintain the current processing capability exhibited by the plasma processing unit 3, so that the mixing ratio is changed as a change value in the direction of the practical lower limit mixing ratio Mmin. Obtain Mx.

  Then, the mixing ratio applied voltage changing unit 9 sends the practical upper limit voltage Vmax specified as the changed value of the applied voltage V by the mixing ratio applied voltage changing value specifying unit 10 to the applied voltage control unit 8, and the electrode of the plasma processing unit 3 The voltage V applied therebetween is changed to the practical upper limit voltage Vmax (step S406). Further, the mixing ratio Mx obtained as the change value of the mixing ratio M is sent to the mixing control unit 7, and the mixing ratio M controlled by the mixing control unit 7 is changed to Mx (step S406).

  FIG. 16 shows that the current operating point Z (MR, VR) is changed to the practical upper limit voltage Vmax (specified change value) and the mixing ratio Mx (practical lower limit mixing ratio Mmin while maintaining the current processing capability of the plasma processing unit 3. A change value calculated in the direction of) is shown in a state where the movement point ZD (Mx, Vmax) is defined. As can be seen from this figure, in Example 4, the mixing ratio M controlled by the mixing controller 7 is lowered (the humidity of the gas D to be mixed is reduced), and humidity reduction control is performed while placing importance on gas processing capacity. It will be realized.

  In Examples 1 and 2 described above, the case where the practical upper limit mixing ratio Mmax and the practical lower limit mixing ratio Mmin are specified as the change values of the mixing ratio M by the mixing ratio applied voltage change value specifying unit 10 has been described. In Examples 3 and 4, the case where the practical lower limit voltage Vmin and the practical upper limit voltage Vmax are designated as the change values of the applied voltage V from the mixture ratio applied voltage change value designation unit 10 has been described. The change value of the mixing ratio M and the change value of the applied voltage V specified from 10 are not limited to these. For example, a change value of the mixing ratio M may be designated as an arbitrary value in the range from the practical upper limit mixing ratio Mmax to the practical lower limit mixing ratio Mmin by an operation such as a dial, and from the practical lower limit voltage Vmin to the practical upper limit voltage Vmax. The change value of the applied voltage V may be designated as an arbitrary value in the range.

  In FIG. 17, the functional block diagram of the principal part of the mixing control part 7 is shown. The mixing control unit 7 includes a first absolute humidity capturing unit 71, a target value storage unit 72, a humidity comparison unit 73, and an opening degree adjustment unit (mixing ratio adjustment unit) 74.

  In the mixing control unit 7, the first absolute humidity capturing unit 71 captures the first absolute humidity hF measured by the humidity sensor S1. The target value storage unit 72 stores a preset target value hsp. The humidity comparison unit 73 compares the first absolute humidity hF captured by the first absolute humidity capture unit 71 with the target value hsp stored in the target value storage unit 72. The opening degree adjusting unit (mixing ratio adjusting unit) 74 is based on the comparison result from the humidity comparing unit 73 so that the first absolute humidity hF and the target value hsp coincide with the opening degree θ of the air supply valve 5. (Mixing ratio M in the mixing unit 2) is adjusted.

  FIG. 18 shows a functional block diagram of the main part of the applied voltage control unit 8. The applied voltage control unit 8 includes a first absolute humidity capturing unit 81, a second absolute humidity capturing unit 82, a humidity difference calculating unit 83, a reference humidity difference range storage unit 84, and an applied voltage adjusting unit 85. And.

  In the applied voltage control unit 8, the first absolute humidity capturing unit 81 captures the first absolute humidity hF measured by the humidity sensor S1, and the second absolute humidity capturing unit 82 is measured by the humidity sensor S2. The second absolute humidity hR is captured. The humidity difference calculation unit 83 calculates a difference Δh (Δh = hF−hR) between the first absolute humidity hF measured by the humidity sensor S1 and the second absolute humidity hR measured by the humidity sensor S2. The reference humidity difference range storage unit 84 stores a preset reference humidity difference range ΔhB ± α.

  The applied voltage adjustment unit 85 checks whether or not the humidity difference Δh calculated by the humidity difference calculation unit 83 is within the reference humidity difference range ΔhB ± α, and the calculated humidity difference Δh is the reference humidity difference range. If the calculated humidity difference Δh is smaller than the reference humidity difference range ΔhB−α so that the voltage V applied between the electrodes of the plasma processing unit 3 is lowered when it is larger than ΔhB + α, the plasma processing unit 3 The voltage V applied between the electrodes of the plasma processing unit 3 is adjusted so as to increase the voltage V applied between the electrodes.

  In FIG. 19, the functional block diagram of the principal part of the mixing ratio applied voltage change part 9 is shown. The mixture ratio applied voltage change unit 9 includes a designated change value acquisition unit 91, an applied voltage change value calculation unit 92, a mixture ratio change value calculation unit 93, and a change value output unit 94.

  In the mixture ratio applied voltage change unit 9, the designated change value acquisition unit 91 acquires the change value designated from the mixture ratio applied voltage change value designation unit 10. When the change value acquired by the designated change value acquisition unit 91 is the change value of the mixing ratio M, the applied voltage change value calculation unit 92 determines that the difference Δh between the first absolute humidity hF and the second absolute humidity hR is A change value Vx of the applied voltage V to the plasma processing unit 3 is calculated under the condition that the current processing capability exhibited by the plasma processing unit 3 is exhibited under the condition of the reference humidity difference range ΔhB ± α. .

  When the change value acquired by the specified change value acquisition unit 91 is the change value of the applied voltage V, the mixing ratio change value calculation unit 93 determines that the difference Δh between the first absolute humidity hF and the second absolute humidity hR is A change value Mx of the mixing ratio M to the mixing control unit 7 is calculated on the condition that the current processing capability exhibited by the plasma processing unit 3 is exhibited in a situation in the reference humidity difference range ΔhB ± α. .

  The change value output unit 94 sends the change value Vx of the applied voltage V calculated by the applied voltage change value calculation unit 92 to the application voltage control unit 8, and changes the mixture ratio M calculated by the mixture ratio change value calculation unit 93. The value Mx is sent to the mixing control unit 7.

  In the above-described embodiment, the value (level) of the voltage V applied between the electrodes of the plasma processing unit 3 is adjusted (controlled) by the applied voltage control unit 8. The voltage V may be periodically applied between them, and the duty ratio of the applied voltage V (the ratio between the on time and the off time within one cycle) may be adjusted (controlled).

  In the above-described embodiment, the scrubber unit 1 adjusts the relative humidity of the processing target gas B to 100%. However, the relative humidity adjusted by the scrubber unit 1 is not limited to 100%. That is, if a stable high-humidity processing target gas B can be obtained, the set value of the relative humidity adjusted by the scrubber unit 1 can be set as appropriate.

  In the above-described embodiment, the duct A1 extending from the downstream side of the plasma processing unit 3 to the mixing unit 2 is provided, and the processed gas E is supplied to the mixing unit 2 as the second gas G2. As shown in FIG. 20, a duct A2 extending from the upstream side of the scrubber unit 1 to the mixing unit 2 is provided, and the processing target gas B before being humidified by the scrubber unit 1 is supplied to the mixing unit 2 as the second gas G2. It may be.

  In the embodiment described above, by providing the mixing ratio applied voltage changing unit 9, energy saving control can be performed while emphasizing gas processing capacity, or humidity reduction control can be performed while emphasizing gas processing capacity. However, the present invention may be applied to a gas processing apparatus that does not include the mixing ratio applied voltage changing unit 9.

[Extension of the embodiment]
The present invention has been described above with reference to the embodiment. However, the present invention is not limited to the above embodiment. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the technical idea of the present invention.

The gas processing apparatus of the present invention can also be applied to so-called reforming for generating a hydrogen-containing gas from hydrocarbons or the like for the purpose of efficiently generating hydrogen used in a fuel cell or the like.
For example, in the case of octane (substance relatively close to the average molecular weight of gasoline) C ₈ H ₁₈ , when supplied to this gas treatment device, the chemical reaction represented by the following formula (1) is promoted, and as a result, hydrogen gas is efficiently generated. can do.
C ₈ H ₁₈ + 8H ₂ O + 4 (O ₂ + 4N ₂ ) → 8CO ₂ + 17H ₂ + 16N ₂ ... (1)

  DESCRIPTION OF SYMBOLS 1 ... Scrubber unit (water processing part), 2 ... Mixing part (mixing part), 3 ... Plasma processing part, 4 ... Control apparatus, 4-1 ... CPU, 4-2 ... RAM, 4-3 ... ROM, 4- 4, 4-5 ... interface, 5 ... air supply valve, 6 ... mixing ratio applied voltage initial control section, 7 ... mixing control section, 8 ... applied voltage control section, 9 ... mixing ratio applied voltage changing section, A ... ventilation path A1, A2 ... duct, S1, S2 ... humidity sensor, 31 ... honeycomb structure, 32, 33 ... electrode, 71 ... first absolute humidity intake part, 72 ... target value storage part, 73 ... humidity comparison part, 74: opening degree adjustment unit (mixing ratio adjustment unit), 81: first absolute humidity intake unit, 82 ... second absolute humidity intake unit, 83 ... humidity difference calculation unit, 84 ... reference humidity difference range storage unit 85 ... Applied voltage adjustment unit 91 ... Designated change value acquisition unit 92 ... Applied voltage change value calculation unit 93 Mixing ratio change value calculation unit, 94 ... change value output section, 100 ... gas treatment device.

Claims (3)

In the gas processing apparatus configured to purify the processing target gas and output the processed gas,
A water treatment unit arranged in a ventilation path and configured to humidify the gas to be treated flowing in the ventilation path;
The gas to be processed before being humidified by the water treatment unit or the treatment before being humidified by the water treatment unit, the first gas is the gas to be treated which is provided downstream of the water treatment unit and humidified by the water treatment unit. A mixing unit configured to adjust humidity by mixing the first gas and the second gas as a second gas,
A honeycomb structure having a large number of through-holes provided downstream of the mixing section and passing through the processing target gas whose humidity has been adjusted in the mixing section as a processing target gas, and the mixing section It has electrodes arranged on the upstream side and the downstream side of the honeycomb structure with respect to the direction in which the gas to be treated passes, and plasma is applied to the through-holes of the honeycomb structure by a voltage applied between the electrodes. A plasma processing unit configured to generate;
A first humidity measuring unit configured to measure the absolute humidity of the gas to be mixed toward the plasma processing unit from the mixing unit as a first absolute humidity;
A second humidity measuring unit configured to measure the mixed processing target gas that has passed through the plasma processing unit as the processed gas, and measure the absolute humidity of the processed gas as a second absolute humidity;
A mixing ratio control unit configured to control a mixing ratio of the first gas and the second gas in the mixing unit such that the first absolute humidity becomes a target value;
Applied voltage control configured to control a voltage applied between the electrodes of the plasma processing unit so that a difference between the first absolute humidity and the second absolute humidity falls within a predetermined humidity difference range. And
Before the control of the mixing ratio by the mixing ratio control unit and the control of the voltage applied between the electrodes of the plasma processing unit by the applied voltage control unit are started, the capability of the plasma processing unit is the practical maximum processing capability. A mixing ratio applied voltage initial control unit configured to control a mixing ratio of the first gas and the second gas and a voltage applied between the electrodes of the plasma processing unit; A gas processing apparatus comprising: The gas treatment device according to claim 1, wherein
The mixing ratio applied voltage initial control unit is:
The mixing ratio determined based on the allowable upper limit value set for the first absolute humidity is set as the practical upper limit mixing ratio, and is determined based on the upper limit value of the applied voltage at which no spark discharge occurs in the plasma processing unit. The first gas so that the voltage applied between the electrodes of the plasma processing unit is the practical upper limit voltage, and the mixed ratio is the practical upper limit mixture ratio. The gas processing apparatus is configured to control a mixing ratio between the first gas and the second gas and a voltage applied between electrodes of the plasma processing unit. The gas treatment device according to claim 1, wherein
Under a situation where the difference between the first absolute humidity measured by the first humidity measuring unit and the second absolute humidity measured by the second humidity measuring unit is within the range of the predetermined humidity difference. The mixture ratio controlled by the mixing ratio control unit is changed within a range from a practical upper limit mixing ratio to a practical lower limit mixing ratio, on condition that the current processing capability exhibited by the plasma processing unit is maintained. And a mixing ratio applied voltage changing unit configured to change a voltage applied between the electrodes of the plasma processing unit within a range from a practical upper limit voltage to a practical lower limit voltage. Processing equipment.