JP5785978B2 - Exhaust gas treatment equipment - Google Patents

Description

  The present invention relates to an exhaust gas treatment apparatus, and more particularly to an apparatus for treating exhaust gas containing hydrogen and ammonia discharged from a device manufacturing apparatus for forming an electronic device such as a semiconductor, a liquid crystal, a photovoltaic power generation panel, and an LED. .

  From the process of manufacturing electronic devices such as semiconductors, liquid crystals, photovoltaic panels, and LEDs, exhaust gases containing combustible components in a wide concentration range, such as hydrogen and ammonia, may be discharged. As a method of treating exhaust gas containing hydrogen and ammonia, air is introduced from outside and mixed into the exhaust gas, and after the concentration of combustible components is diluted below the lower explosion limit, ammonia, which is a toxic component, is absorbed by a wet scrubber. A method is known (for example, refer to Patent Document 1). In addition, a method is also known in which hydrogen and ammonia are combusted using a combustion-type abatement apparatus while monitoring the flow rate of exhaust gas (see, for example, Patent Document 2).

Japanese Patent No. 3352476 Japanese Patent No. 4690597

  However, in the method described in Patent Document 1, since a large amount of air is introduced from the outside, there is a problem that the processing amount of exhaust gas in the wet scrubber increases, and the wet scrubber becomes large. Since a large amount of waste water is generated, there is also a problem that waste liquid treatment costs increase. Moreover, in the method described in Patent Document 2, although the flow rate of exhaust gas is monitored, operation is performed without information on ammonia and concentration in the exhaust gas, so it is necessary to supply an excessive amount of fuel to the combustion abatement device. There was a problem that running cost increased.

  Accordingly, an object of the present invention is to provide an exhaust gas treatment apparatus that can efficiently treat exhaust gas containing hydrogen and ammonia.

In order to achieve the above object, an exhaust gas treatment apparatus of the present invention includes an exhaust gas treatment apparatus that treats exhaust gas containing hydrogen and ammonia, a first detoxification apparatus that performs a primary treatment of the exhaust gas, and the first detoxification apparatus. A second abatement device that performs secondary treatment of the exhaust gas at a later stage, a temperature measuring means that measures the temperature of the primary treatment gas derived from the first abatement device, and a primary treatment gas that is measured by the temperature measuring means. Control is performed to lower the operating temperature of the first abatement device when the temperature exceeds a preset high temperature set temperature higher than a preset target temperature, and the temperature of the primary processing gas measured by the temperature measuring means is and control means for performing control for increasing the operating temperature of the first abatement device when below the target temperature set lower than the low temperature side set temperature, the first abatement apparatus in combustion type abatement system Ri, the second scrubber is catalytic oxidation type abatement system is characterized in that the target temperature is the processing temperature of the catalytic oxidation type abatement system.

Moreover, the exhaust gas treatment apparatus of the present invention is an exhaust gas treatment apparatus using a combustion-type abatement apparatus as the first abatement apparatus, wherein the combustion-type abatement apparatus supplies the amount of fuel supplied to the combustion-type abatement apparatus. A fuel supply means capable of adjusting the pressure, an air supply means capable of adjusting the amount of air supplied to the combustion-type abatement apparatus, and a cooling water supply means for supplying cooling water to the combustion-type abatement apparatus. The control means supplies cooling water to the combustion-type abatement device by the cooling water supply means when the measured temperature of the temperature measuring means exceeds a preset first high temperature side set temperature, and the measured temperature is Supply of cooling water is stopped when the temperature falls to the target temperature, and when the measured temperature exceeds a preset second high temperature side set temperature, supply of air supplied to the combustion-type abatement device by the air supply means Increase the amount At the same time, when the measured temperature falls to the target temperature, the supply amount of the atmosphere is returned to the supply amount before the increase, and when the temperature measured by the temperature measurement means falls below the preset first low temperature side set temperature, the atmosphere The supply amount of the atmosphere supplied to the combustion-type abatement apparatus is reduced by the supply means, and when the measured temperature rises to the target temperature, the supply amount of the atmosphere is returned to the supply amount before the decrease, and the temperature measurement means When the measured temperature falls below the preset second low temperature side set temperature, the amount of fuel supplied to the combustion-type abatement device is increased by the fuel supply means, and the measured temperature rises to the target temperature The fuel supply amount is returned to the supply amount before the decrease.

Furthermore, the exhaust gas treatment device of the present invention is an exhaust gas treatment device for treating exhaust gas containing hydrogen and ammonia, and a first detoxification device that performs a primary treatment of the exhaust gas, A second abatement apparatus that performs secondary treatment, a temperature measurement means that measures the temperature of the primary treatment gas derived from the first abatement apparatus, and the temperature of the primary treatment gas that is measured by the temperature measurement means are preset. The temperature of the primary processing gas measured by the temperature measuring means is lower than the target temperature while controlling to lower the operating temperature of the first detoxifying device when the temperature exceeds the high temperature side set temperature set higher than the target temperature. Control means for performing control to increase the operating temperature of the first abatement device when the temperature falls below a set low temperature side set temperature, and the first abatement device is a heater heating abatement device, The second scrubber is catalytic oxidation type abatement device, a processing temperature of the target temperature is the catalytic oxidation type abatement system, said heater heating type abatement device, heating the heater heating type abatement system Heater output adjusting means capable of adjusting the output of the heater to be heated, air supply means capable of adjusting the amount of air supplied to the heater heating type abatement apparatus, and cooling water is supplied to the heater heating type abatement apparatus Cooling water supply means, and the control means supplies cooling water to the heater-heated abatement device by the cooling water supply means when the temperature measured by the temperature measurement means exceeds a preset first high temperature side set temperature. When the measured temperature falls to the target temperature, the cooling water supply is stopped, and when the measured temperature exceeds the preset second high temperature side set temperature, the air supply means is Increase the supply amount of air supplied to the heater-heated detoxification device, and return the supply amount of air to the supply amount before the increase when the measured temperature falls to the target temperature, and measure with the temperature measuring means When the measured temperature falls below the preset first low temperature side set temperature, the supply amount of air supplied to the heater-heated abatement device by the air supply means is reduced, and the measured temperature rises to the target temperature Sometimes the supply amount of the atmosphere is returned to the supply amount before the decrease, and when the temperature measured by the temperature measurement unit falls below the preset second low temperature side set temperature, the heater output adjustment unit increases the heater output. In addition, when the measured temperature rises to the target temperature, the output of the heater is returned to the output before the increase.

  The first high temperature side set temperature is set to a temperature higher than the second high temperature side set temperature, and the first low temperature side set temperature is set to a temperature higher than the second low temperature side set temperature. It is said.

  According to the exhaust gas treatment apparatus of the present invention, since the operation temperature of the first abatement apparatus is controlled to approach the target temperature, the exhaust gas detoxification process while suppressing the consumption of energy for treating hydrogen and ammonia in the exhaust gas. Can be performed efficiently. For example, when the first abatement apparatus is a combustion abatement apparatus, the fuel consumption of the combustion abatement apparatus can be suppressed, and when the first abatement apparatus is a heater heating abatement apparatus, heater heating is performed. The amount of power consumption of the expression abatement device can be suppressed. Further, by using a catalytic oxidation type detoxifying device as the second detoxifying device, alkaline waste water containing ammonia is not generated.

It is explanatory drawing which shows the 1st form example of the waste gas processing apparatus of this invention. It is explanatory drawing which shows the 2nd form example of the waste gas processing apparatus of this invention. It is explanatory drawing which shows the 3rd example of an exhaust gas processing apparatus of this invention.

FIG. 1 shows a first embodiment of an exhaust gas treatment apparatus of the present invention. This exhaust gas treatment apparatus uses hydrogen (H ₂ ), ammonia (NH ₃ ), nitrogen as a source gas (process gas) and a carrier gas. (N ₂ ) is a first abatement device for performing exhaust gas discharged from the CVD apparatus 11 using other gases, and for performing a primary abatement process for removing ammonia and hydrogen. Combustion-type abatement apparatus 12, catalytic oxidation-type abatement apparatus 13, which is a second abatement apparatus for performing secondary abatement treatment for removing ammonia that could not be processed by combustion-type abatement apparatus 12, and combustion Temperature measuring means 14 for measuring the temperature of the primary processing gas derived from the type abatement apparatus 12, and control for controlling the operating state of the combustion type abatement apparatus 12 based on the temperature of the primary processing gas measured by the temperature measuring means With means 15 To have.

  The control means 15 controls to lower the operating temperature of the combustion-type abatement apparatus 12 when the temperature of the primary processing gas measured by the temperature measuring means 14 exceeds a preset high temperature side temperature set higher than a preset target temperature. And controlling the temperature of the primary processing gas measured by the temperature measuring means 14 to be increased when the temperature of the primary processing gas is lower than the low temperature set temperature set lower than the target temperature. .

  The combustion-type abatement apparatus 12 includes a first fuel supply unit 16 that supplies a certain amount of fuel for forming a combustion seed fire, and a second fuel supply unit 17 that supplies a fuel for adjusting the amount of combustion. And an air supply means 18 for supplying air to the combustion-type abatement apparatus 12 and a cooling water supply means 19 for supplying cooling water to the combustion-type abatement apparatus 12. Has a minimum air supply amount for combustion and for cooling the primary processing gas after combustion. For example, the control unit 15 can change the flow rate of fuel supplied from the second fuel supply unit 17, the flow rate of air supplied from the air supply unit 18, and the flow rate of cooling water supplied from the cooling water supply unit 19, Adjust by opening the valve.

  The control means 15 is set with a target temperature as a temperature suitable for treating the ammonia remaining in the primary treatment gas by the catalytic oxidation type detoxifying device 13, and the second fuel supply means 17, the air supply means The temperature for controlling 18 and the cooling water supply means 19 is set.

  As the set temperature higher than the target temperature, the first high temperature side set temperature H1 for starting the supply of the cooling water from the cooling water supply means 19 and the second high temperature side set temperature H2 for increasing the supply amount of the atmosphere from the air supply means. As the set temperature lower than the target temperature, the first low temperature side set temperature L1 for decreasing the supply amount of air from the air supply means and the supply amount of fuel from the second fuel supply means 17 are increased. A second low temperature side set temperature L2 is set. The relationship between the first high temperature side set temperature H1 and the second high temperature side set temperature H2 is H1> H2, and the relationship between the first low temperature side set temperature L1 and the second low temperature side set temperature L2 is L1>. L2.

  In the exhaust gas treatment apparatus thus formed, the control unit 15 operates in accordance with the temperature change of the combustion type abatement apparatus 12 caused by the fluctuation of the combustible component concentration in the exhaust gas discharged from the CVD apparatus 11, and the combustion type removal The temperature of the primary processing gas that is derived from the harmful device 12 and introduced into the catalytic oxidation type detoxifying device 13 is set to a temperature that is optimal for the treatment of ammonia in the catalytic oxidation type detoxifying device 13, that is, a temperature at which the catalytic activity is high. Adjust.

  For example, in the CVD apparatus 11, the type and amount of gas to be supplied change with the progress of the vapor phase growth process. For example, ammonia is not supplied at the initial stage of the process in which preheating is performed from the start of the process. Hydrogen and nitrogen are supplied, the supply of ammonia is started in the middle of the process, and then the supply of hydrogen is stopped. Further, in the latter half of the process, a process of restarting the hydrogen supply is performed.

  Accordingly, there is a period in which ammonia and hydrogen are not supplied during the process, and a period in which both are supplied at the same time, and the hydrogen concentration and ammonia concentration in the exhaust gas discharged from the CVD apparatus 11 change greatly. Then, a combustion state changes with the concentration change of hydrogen and ammonia which are combustible components. For this reason, when the concentration of hydrogen or ammonia increases, the temperature of the combustion abatement device 12 increases due to an increase in the combustion amount, and when the concentration of hydrogen or ammonia decreases, the temperature of the combustion abatement device 12 decreases due to the decrease in the combustion amount. descend. As a result, when the temperature of the primary processing gas derived from the combustion type detoxifying device 12 fluctuates and the temperature of the primary processing gas deviates from the optimum processing temperature range in the catalytic oxidation type detoxifying device 13, the catalytic oxidation type detoxifying device. There is a possibility that the ammonia removal treatment at 13 cannot be performed sufficiently.

  Therefore, the temperature of the primary processing gas is measured by the temperature measuring means 14 so that the temperature of the primary processing gas falls within the optimum processing temperature range in the catalytic oxidation type abatement apparatus 13. First, when the temperature of the primary processing gas measured by the temperature measuring means 14 at the initial stage of the process is the target temperature, the temperature of the combustion-type abatement device 12 increases due to the increase in the combustible component concentration due to the start of the supply of ammonia. When the temperature measured by the temperature measuring means 14 rises to the second high temperature side set temperature H2, the amount of air supplied from the air supply means 18 is increased, and the temperature is higher than the combustion temperature of the combustion type abatement apparatus 12. Lower the temperature of the primary process gas by mixing low air. When the measured temperature decreases to the target temperature due to the increase in the air supply amount, the air supply amount is returned to the supply amount before the increase.

  Further, when the temperature measured by the temperature measuring means 14 rises to the first high temperature side set temperature H1, the supply of cooling water is started from the cooling water supply means 19, and the cooling water is sprayed into the combustion-type abatement apparatus 12 by spraying. The temperature of the primary treatment gas is lowered using the latent heat of vaporization of water. Also in this case, when the measured temperature falls to the target temperature, the supply of cooling water is stopped.

  Further, when the temperature of the combustion type abatement apparatus 12 decreases due to a decrease in the combustible component concentration due to the stop of the supply of hydrogen to the CVD apparatus 11, and the temperature measured by the temperature measuring means 14 decreases to the first low temperature side set temperature L1. The temperature of the primary processing gas is raised by reducing the amount of air supplied from the air supply means 18 and reducing the amount of air mixed into the exhaust gas. When the measured temperature rises to the target temperature due to the decrease in the air supply amount, the air supply amount is returned to the supply amount before the decrease. Further, when the temperature measured by the temperature measuring means 14 falls to the second low temperature side set temperature L2, the amount of fuel supplied from the second fuel supply means 17 is increased to increase the combustion amount, and the temperature of the primary processing gas is increased. Raise. When the measured temperature rises to the target temperature due to the increase in the fuel supply amount, the fuel supply amount is returned to the supply amount before the increase.

  Thus, by controlling the fuel supply amount, the air supply amount, and the cooling water supply amount according to the temperature of the primary processing gas, the temperature of the primary processing gas is set to the optimum processing temperature in the catalytic oxidation type abatement apparatus 13, that is, The target temperature can be adjusted reliably. In addition, fuel consumption can be reduced by reducing the fuel supply amount at the first stage of temperature rise. Furthermore, various fuels can be used as the fuel, but by using hydrogen used in the CVD apparatus 11 as a fuel, it is not necessary to provide a separate facility for fuel, and the generation of carbon dioxide is also suppressed. be able to. Moreover, by starting the supply of air and the supply of cooling water at a temperature higher than the decrease in the amount of fuel supply, an increase in the amount of exhaust gas can be suppressed and no alkaline waste water is generated.

  FIG. 2 shows a second embodiment of the exhaust gas treatment apparatus of the present invention. In the following description, the same components as those of the exhaust gas treatment apparatus shown in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The exhaust gas treatment apparatus shown in this embodiment uses a heater heating type detoxifying device 21 as the first detoxifying device. This heater heating type abatement device 21 is a heater for heating the heater heating type abatement device 21, and a first heater 22 for always ensuring a constant heating amount, and a second heater 23 capable of adjusting the heater output. And an air supply means 24 capable of adjusting the amount of air supplied to the heater-heated detoxifying device, and a cooling water supply means 25 for supplying cooling water to the heater-heated detoxifying device.

  In the subsequent stage of the heater heating type detoxifying device 21, the temperature of the primary processing gas derived from the heater heating type detoxifying device 21 and introduced into the catalytic oxidation type detoxifying device 13 is measured as in the first embodiment. And a control means 27 for controlling the operating state of the heater-heating type detoxifying device 21 based on the temperature of the primary processing gas measured by the temperature measuring means 26.

  The control unit 27 is set with a target temperature similar to that of the first embodiment, a first high temperature side set temperature H1 and a second high temperature side set temperature H2 as set temperatures on the high temperature side, and set on the low temperature side. A first low temperature side set temperature L1 and a second low temperature side set temperature L2 are set as temperatures.

  Also in the present embodiment, as in the first embodiment, the temperature of the primary processing gas derived from the heater heating type detoxifying device 21 is measured by the temperature measuring means 26, and the measured temperature of the primary processing gas is the second high temperature. When the temperature rises to the side set temperature H2, the amount of air supplied from the air supply means 24 is increased to lower the temperature of the primary processing gas, and when the temperature of the primary processing gas drops to the target temperature, the amount of air supply Return to the supply before the increase. Further, when the temperature measured by the temperature measuring means 26 rises to the first high temperature side set temperature H1, the cooling water supply starts from the cooling water supply means 25, and the cooling water is sprayed into the combustion abatement apparatus 12. Thus, when the temperature of the primary processing gas is lowered and the measured temperature is lowered to the target temperature, the supply of the cooling water is stopped.

  Further, when the temperature measured by the temperature measuring means 26 is lowered to the first low temperature side set temperature L1, the supply amount of the atmosphere from the atmosphere supply means 24 is decreased to raise the temperature of the primary processing gas, and the measured temperature becomes When the temperature rises to the target temperature, the supply amount of air is returned to the supply amount before the decrease. Further, when the temperature measured by the temperature measuring means 26 falls to the second low temperature side set temperature L2, the output of the second heater 23 is increased to raise the temperature of the primary processing gas, and the measured temperature rises to the target temperature. When this happens, the output of the second heater 23 is returned to the output before the increase.

  In this way, by controlling the heater output, the air supply amount, and the cooling water supply amount of the heater heating type detoxifying device 21 according to the temperature of the primary process gas, the primary process gas is controlled in the same manner as in the first embodiment. The temperature can be reliably adjusted to the optimum processing temperature in the catalytic oxidation type abatement apparatus 13, that is, the target temperature. In addition, by reducing the heater output at the first stage of temperature rise, power consumption can be reduced, and by starting the supply of air and cooling water at a temperature higher than the decrease in heater output, It is possible to suppress the increase in the amount and the generation of alkaline waste water.

  FIG. 3 shows a third embodiment of the exhaust gas treatment apparatus of the present invention, and shows an embodiment in which exhaust gas discharged from a plurality of CVD apparatuses 11 is processed by one exhaust gas treatment apparatus. Exhaust gas discharged from the plurality of CVD apparatuses 11 is introduced into the combustion type abatement apparatus 12 and subjected to the combustion abatement process, and the primary processing gas derived from the combustion type abatement apparatus 12 is converted into the catalytic oxidation type abatement apparatus. By introducing the catalyst 13 into the catalyst and performing a catalytic oxidation process, a detoxification process of hydrogen and ammonia in the exhaust gas is performed.

  As described above, even when the exhaust gas discharged from the plurality of CVD apparatuses 11 is subjected to the detoxification process, the temperature of the primary treatment gas derived from the combustion type detoxification apparatus 12 is measured by the temperature measuring means 14 and the measured primary is measured. By controlling the fuel supply amount, the air supply amount, and the cooling water supply amount in accordance with the temperature of the processing gas, and adjusting the temperature of the primary processing gas to the optimum processing temperature in the catalytic oxidation type abatement apparatus 13, the first embodiment As in the example, the fuel consumption can be reduced, the increase in the amount of exhaust gas can be suppressed, and no alkaline waste water can be generated. Instead of the combustion type abatement apparatus 12, the heater heating type abatement apparatus 21 shown in the second embodiment can be used.

In each embodiment, the first high temperature side set temperature H1, the second high temperature side set temperature H2, the first low temperature side set temperature L1, the second low temperature side set temperature L2, the fuel increase / decrease amount, the heater output with respect to the target temperature. the amount of increase or decrease, increase or decrease the amount of air supply amount, exhaust gas processing amount and apparatus configuration in the first scrubber, apparatus size, further, be determined depending on conditions such as optimum temperature range in the second scrubber Is possible. In addition, the temperature at which the fuel supply amount, the heater output, the air supply amount, and the cooling water supply amount are increased / decreased and then returned to the state before the increase / decrease can be set separately from the target temperature.

  DESCRIPTION OF SYMBOLS 11 ... CVD apparatus, 12 ... Combustion type abatement apparatus, 13 ... Catalytic oxidation type abatement apparatus, 14 ... Temperature measuring means, 15 ... Control means, 16 ... 1st fuel supply means, 17 ... 2nd fuel supply means, 18 DESCRIPTION OF SYMBOLS ... Air supply means, 19 ... Cooling water supply means, 21 ... Heater heating type abatement device, 22 ... First heater, 23 ... Second heater, 24 ... Air supply means, 25 ... Cooling water supply means, 26 ... Temperature measurement Means, 27 ... control means

Claims (5)

In an exhaust gas treatment apparatus for treating exhaust gas containing hydrogen and ammonia, a first abatement apparatus that performs a primary treatment of the exhaust gas, and a second abatement apparatus that performs a secondary treatment of the exhaust gas at a subsequent stage of the first abatement apparatus Temperature measuring means for measuring the temperature of the primary processing gas derived from the first abatement apparatus, and a high temperature side setting in which the temperature of the primary processing gas measured by the temperature measuring means is set higher than a preset target temperature When the temperature exceeds the temperature, control is performed to lower the operating temperature of the first abatement apparatus, and the temperature of the primary processing gas measured by the temperature measuring means falls below the low temperature set temperature set lower than the target temperature. Control means for performing control to increase the operating temperature of the first abatement device, the first abatement device is a combustion abatement device, and the second abatement device is a catalytic oxidation abatement device And Exhaust gas treatment device serial target temperature is the processing temperature of the catalytic oxidation type abatement system. The combustion-type abatement apparatus includes a fuel supply means capable of adjusting a supply amount of fuel supplied to the combustion-type abatement apparatus, and an air supply means capable of adjusting an air supply amount supplied to the combustion-type abatement apparatus. And a cooling water supply means for supplying cooling water to the combustion-type abatement apparatus, wherein the control means is configured such that when the measured temperature of the temperature measuring means exceeds a preset first high temperature side set temperature, The cooling water is supplied to the combustion-type abatement device by the cooling water supply means, and the cooling water supply is stopped when the measured temperature falls to the target temperature, and the measured temperature is set to the second high temperature side preset temperature set in advance. Increase the amount of air supplied to the combustion-type abatement device by the air supply means when it exceeds, and return the amount of air supply to the amount before the increase when the measured temperature falls to the target temperature, Temperature measurement When the temperature measured by the means falls below a preset first low temperature side set temperature, the amount of air supplied to the combustion-type abatement device is reduced by the air supply means, and the measured temperature becomes the target temperature. When the temperature rises, the supply amount of the atmosphere is returned to the supply amount before the decrease, and when the temperature measured by the temperature measurement means falls below the preset second low temperature side set temperature, the fuel supply means turns the combustion type abatement device. with increasing supply amount of fuel supplied, measured temperature exhaust gas treatment apparatus according to claim 1, wherein returning to the supply amount before decreasing the amount of fuel supplied when raised to the target temperature. The first hot side set temperature is set to the second hot side set temperature higher temperatures, the first low temperature side set temperature according to claim 2, wherein it is set to a temperature higher than the second low temperature side set temperature Exhaust gas treatment equipment. In an exhaust gas treatment apparatus for treating exhaust gas containing hydrogen and ammonia, a first abatement apparatus that performs a primary treatment of the exhaust gas, and a second abatement apparatus that performs a secondary treatment of the exhaust gas at a subsequent stage of the first abatement apparatus Temperature measuring means for measuring the temperature of the primary processing gas derived from the first abatement apparatus, and a high temperature side setting in which the temperature of the primary processing gas measured by the temperature measuring means is set higher than a preset target temperature When the temperature exceeds the temperature, control is performed to lower the operating temperature of the first abatement apparatus, and the temperature of the primary processing gas measured by the temperature measuring means falls below the low temperature set temperature set lower than the target temperature. Control means for performing control to raise the operating temperature of the first abatement device sometimes, the first abatement device is a heater heating type abatement device, and the second abatement device is a catalytic oxidation type abatement apparatus There is a processing temperature of the target temperature is the catalytic oxidation type abatement system, said heater heating type abatement system includes an adjustable heater output adjustment means output of the heater for heating the heater heating type abatement system , Air supply means capable of adjusting the amount of air supplied to the heater-heated detoxifying device, and cooling water supply means for supplying cooling water to the heater-heated detoxifying device, and the control means includes: When the measured temperature of the temperature measuring means exceeds a preset first high temperature side set temperature, the cooling water supply means supplies cooling water to the heater-heated abatement device, and the measured temperature decreases to the target temperature. Sometimes the cooling water supply is stopped, and when the measured temperature exceeds the preset second high temperature side set temperature, it is supplied to the heater-heated abatement device by the air supply means The air supply amount is increased, and when the measured temperature falls to the target temperature, the air supply amount is returned to the supply amount before the increase, and the temperature measured by the temperature measuring means is set to the first low temperature side setting in advance. When the air temperature is lower than the temperature, the air supply means reduces the air supply amount supplied to the heater-heated abatement device, and when the measured temperature rises to the target temperature, the air supply amount is reduced before the decrease. When the temperature measured by the temperature measuring means falls below the preset second low temperature side preset temperature, the heater output adjusting means increases the heater output and the measured temperature rises to the target temperature. exhaust gas treatment apparatus to return to the output of the previous increase the output of the heater. The first hot side set temperature is set to the second hot side set temperature higher temperatures, the first low temperature side set temperature according to claim 4, wherein it is set to a temperature higher than the second low temperature side set temperature Exhaust gas treatment equipment.

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