JP5121637B2 - Denitration catalyst regeneration method, denitration catalyst regeneration apparatus, and exhaust gas treatment apparatus using the same - Google Patents

Description

  The present invention relates to a denitration catalyst regeneration method, a denitration catalyst regeneration apparatus, and an exhaust gas treatment apparatus using the same, and more particularly, denitration treatment through exhaust gas containing nitrogen oxides (NOx) discharged from combustion equipment such as incineration equipment. The present invention relates to a denitration catalyst regeneration method, a denitration catalyst regeneration apparatus, and an exhaust gas treatment apparatus using the same.

The exhaust gas discharged from the incineration facility that incinerates waste such as various garbage contains NOx and other harmful substances, and denitration reaction with a denitration catalyst by injecting ammonia (NH ₃ ) into the exhaust gas. Decomposed and removed by equipment. However, sulfur oxide (SOx, especially SO ₃ ), hydrogen chloride (HCL), etc. contained in the exhaust gas react with this NH ₃ to produce acidic ammonium sulfate (NH ₄ HSO ₄ ), ammonium chloride (NH ₄ CL), etc. It produces, poisons the denitration catalyst surface, and degrades the catalyst performance over time.

  Therefore, a method of regenerating and using a deteriorated catalyst has been performed. For example, a method of once removing the catalyst from the reaction facility and volatilizing acidic ammonium sulfate and ammonium chloride in a heating furnace (see, for example, Patent Document 1), a method of removing the catalyst once from the denitration reaction facility and washing away the acidic ammonium sulfate and ammonium chloride with water, There is a method in which combustion gas is drawn into a denitration catalyst device from another incineration facility in operation, acid ammonium sulfate and ammonium chloride are volatilized in the denitration catalyst device, and discharged again to another exhaust gas treatment facility.

  Furthermore, as a catalyst regeneration method that can regenerate the catalyst without stopping the incinerator, the interior of the catalyst tower is divided into two or more chambers, and the catalyst regeneration is performed one by one while exhaust gas is discharged into the remaining chambers. A method of processing through is also proposed. Specifically, as shown in FIG. 4, the catalyst column 120 is used for decomposing NOx and organic halogen compounds contained in the exhaust gas filled in the exhaust gas supplied from the incinerator 110 into the catalyst column 120, The inside of the catalyst tower 120 is divided into two or more chambers, and NOx and organic halogen compounds contained in the exhaust gas can be decomposed through the remaining chambers while the catalyst is regenerated one by one (for example, Patent Document 2). reference).

Japanese Patent Laid-Open No. 2001-219078 Japanese Patent Laid-Open No. 10-192657

  However, the above-described prior art method has a problem that the structure of the catalytic reaction tower is complicated and equipment costs are required for that purpose, so that a considerable processing cost is required.

In addition, when the catalyst that has deteriorated is taken out from the catalyst equipment, transported to the regeneration site, and the catalyst is attached to the regeneration equipment for regeneration, the catalyst may be removed, transported, or impacted at the time of installation. There is a possibility that the catalyst may be damaged, and further, there is a problem that a support such as vanadium pentoxide (V ₂ O ₅ ), which is a catalyst component, is eluted together with a poisoning substance during washing with water.

  In the method using the catalyst tower divided into two or more chambers, the catalyst tower to be regenerated cannot be used for denitration during regeneration. Therefore, in order to denitrate NOx in exhaust gas even during regeneration of the catalyst tower. It is necessary to increase the volume of the catalyst tower.

  Therefore, in view of the above-mentioned problems of the prior art, the object of the present invention is to perform efficient heating and regeneration of a catalyst on site without removing a catalyst from the denitration catalyst device without requiring a complicated and expensive equipment configuration. An object of the present invention is to provide a denitration catalyst regeneration method, a denitration catalyst regeneration apparatus, and an exhaust gas treatment apparatus using the same.

  As a result of extensive research, the present inventor has found that the above object can be achieved by a denitration catalyst regeneration method, a denitration catalyst regeneration apparatus, and an exhaust gas treatment apparatus using the same, and completes the present invention. Arrived.

That is, the present invention introduces a chemical for neutralizing the acidic gas component in the exhaust gas generated from the combustion facility into the exhaust gas, and processes the fly ash and / or reaction product in the exhaust gas with a dust collector. In addition, in the exhaust gas treatment device for denitrating nitrogen oxides in the exhaust gas by the denitration catalyst device supplied with ammonia,
A method for regenerating a denitration catalyst filled in the denitration catalyst device, wherein when the combustion equipment is stopped, a part of the gas in the exhaust gas treatment system is heated to 350 to 500 ° C. to be used as a regeneration gas in the denitration catalyst device. In addition to forming a circulation system to supply in a circulating manner, a part of the regeneration gas is taken out, the neutralization treatment and the dust removal treatment are performed, and the ammonia removal treatment in the regeneration gas is further performed.

Alternatively, the present invention provides a chemical introduction section for introducing a chemical for neutralizing an acidic gas component in exhaust gas generated from combustion equipment into the exhaust gas, and treats fly ash and / or reaction products in the exhaust gas. A denitration catalyst regeneration device filled in the denitration catalyst device, wherein the denitration catalyst device is a denitration catalyst device that is supplied with ammonia and denitrating the nitrogen oxides in the exhaust gas.
Closing means for closing the inlet-side flow path and outlet-side flow path of the denitration catalyst device to block the exhaust gas flow channel, and connecting to the exhaust gas flow channels upstream and downstream of the denitration catalyst device blocked by the closing means A regenerative gas flow path, a gas feeding means and a heating means provided in the regenerative gas flow path, and a circulation system is formed, and the introduction flow path to which the drug introduction section is connected and the regenerative gas flow path are connected A processing gas channel, a bypass channel connected from the middle of the dust collector and the inlet side closing means to the downstream side of the outlet side closing means, and an ammonia removal device provided in the bypass channel, The processing system is configured,
A part of the regeneration gas heated while circulating in the circulation system is taken out, introduced into the regeneration gas treatment system through the treatment gas flow path, the neutralization treatment and the dust removal treatment are performed, and the regeneration gas is further removed. It is characterized by carrying out ammonia removal treatment therein.

In the regeneration of the denitration catalyst disposed in the exhaust gas treatment device, there are some problems as described above. The present invention
(A) A part of the gas in the exhaust gas treatment system before and after the denitration treatment is used for catalyst regeneration without preparing a separate regeneration gas. (B) A circulation system for supplying heated regeneration gas to the denitration catalyst. (C) A part of the regeneration gas to be formed is taken out, and neutralization treatment and dust removal treatment are performed using the treatment function of the exhaust gas treatment device, and further, ammonia removal treatment in the regeneration gas is performed to complete the process. This makes it possible to regenerate the denitration catalyst. Accordingly, there is provided a denitration catalyst regeneration method or a denitration catalyst regeneration apparatus capable of efficiently heating and regenerating a catalyst on site without requiring a complicated and costly equipment configuration and without removing the catalyst from the denitration catalyst apparatus. It became possible.

  The present invention is the above-described denitration catalyst regeneration device, wherein a downstream side of the ammonia removal device in the bypass flow path and a downstream side of the denitration catalyst device in the regeneration gas flow path are connected, and one of the regeneration gases after the ammonia removal treatment is provided. Is introduced into the circulation system.

  The above regenerator is characterized in that a part of the regenerated gas is taken out and purified and neutralized and discharged. On the other hand, the regeneration gas used in the circulation system is preferably a purified gas. The present invention introduces such a purified gas into the circulation system again as a regeneration gas, thereby connecting the regeneration gas circulation system and the regeneration gas processing system in both directions to further improve the regeneration function of the denitration catalyst. It becomes possible.

  The present invention is an exhaust gas treatment apparatus that exhausts exhaust gas discharged from a combustion facility and introduced through a waste heat boiler and a temperature-decreasing tower, and performs neutralization treatment, dust removal treatment and denitration treatment, and discharges it as a purified gas. Then, the regeneration process of the denitration catalyst filled in the denitration catalyst apparatus for performing the denitration process is performed using the regeneration method or the regeneration apparatus.

  In an apparatus for treating exhaust gas discharged from a combustion facility, the denitration catalyst plays an important role, and the regeneration treatment is indispensable for maintaining and ensuring the denitration function. The present invention makes it possible to regenerate the denitration catalyst in a self-contained manner as in the above (a) to (c), and by using such a regeneration method or regeneration device, exhaust gas that is efficient even at the installation site. An apparatus capable of processing can be configured.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. A denitration catalyst regeneration apparatus according to the present invention (hereinafter referred to as “the present apparatus”) closes an inlet-side flow path and an outlet-side flow path of the denitration catalyst apparatus to block an exhaust gas flow path, A circulation system is formed by the gas feeding means and heating means provided there, and a regeneration gas treatment system is constituted by the neutralization treatment means, the dust collector and the ammonia removal device provided in the bypass flow path, and the circulation A part of the regenerated gas heated while circulating in the system is taken out, introduced into the regenerated gas treatment system, neutralized and dust-removed, and further ammonia removed.

<One embodiment of the present apparatus (first configuration example)>
An outline of one embodiment of the present apparatus is shown in FIG. 1 (first configuration example). FIG. 1A illustrates the operating state of the present apparatus during a normal exhaust gas treatment operation, and FIG. 1B illustrates the operating state of the apparatus during regeneration of the denitration catalyst filled in the denitration catalyst apparatus 1. To do.

  In FIG. 1 (A), the exhaust gas discharged from the combustion facility (not shown) is introduced into the introduction flow channel La through the exhaust gas flow channel Lo, and the exhaust gas treatment is performed. That is, a chemical introduction unit 2 that introduces a chemical for neutralizing acidic gas components in exhaust gas, a dust collector 3 that processes fly ash and / or reaction products in exhaust gas, and ammonia are supplied, Neutralization, dust removal treatment and denitration treatment are performed via a denitration catalyst device 1 for denitration treatment of nitrogen oxides (NOx) in the exhaust gas. At this time, the exhaust gas flow channel Lo is blocked by the flow channels functioning during regeneration and the dampers V1 to V5.

In FIG. 1B, the exhaust gas flow path Lo is blocked by the damper Va, and new introduction of exhaust gas is stopped. At the same time, the supply flow path Lb of the dust collector 3 and the discharge flow path Le on the outlet side of the denitration catalyst apparatus 1 are closed by the dampers Vc and Vd (corresponding to closing means), and the introduction flow path Lc to the denitration catalyst apparatus 1 A regeneration gas circulation system is formed by the supply passage Ld and the regeneration gas passage Lr, and the regeneration treatment of the denitration catalyst is performed. Further, the regeneration gas passage Lr includes a treatment gas passage Ls via a flow rate adjustment damper D1, and a regeneration gas treatment passage (regeneration gas treatment system) including an introduction passage La, a supply passage Lb, and a bypass passage Lt. ), And neutralization treatment, dust removal treatment, and ammonia removal treatment of components in the regeneration gas such as SOx and NH ₃ desorbed from the denitration catalyst are performed and discharged as a purified gas.

At this time, the regeneration treatment of the denitration catalyst in the regeneration gas circulation system is performed by the regeneration gas heated by the heater 4 (corresponding to the heating means) provided in the circulation flow path by the fan 5 (corresponding to the gas feeding means). It is performed by being fed cyclically to the denitration catalyst device 1. In other words, SOx, HCL, NH _3, etc. generated by the thermal decomposition of acidic ammonium sulfate or ammonium chloride that poisons the catalyst surface are desorbed from the catalyst surface and entrained by the regeneration gas, so that the catalyst surface is It can be regenerated and activated. In addition, a part of the regeneration gas containing SOx, HCL, NH ₃ or the like is fed to the regeneration gas processing system, and an acid gas component such as SOx or HCL is neutralized by the chemical introduced from the chemical introduction unit 2. Then, the reaction product generated thereby is removed by the dust collecting device 3, and further, components such as untreated NH ₃ are removed by the ammonia removing device 6, thereby being purified to a level that can be discharged to the atmosphere. The regeneration gas can be treated. At this time, a part of the regeneration gas is supplied to the regeneration gas processing system and the regeneration gas in the circulation system is reduced, so that clean air is sucked into the circulation system via the damper V6. Further, the regeneration gas fed to the regeneration gas processing system is adjusted by mixing clean air through a damper V7 in order to obtain a gas temperature suitable for processing in the dust collector 3.

  Here, what is handled by this apparatus is exhaust gas that requires denitration treatment, specifically, exhaust gas discharged from combustion facilities such as various boilers and incinerators. In addition to NOx, SOx and HCL Since some acidic components such as these are included, some cleaning treatment is required when discharging from a chimney or the like to the atmosphere.

[Functions of components of this device]
In the present apparatus, as a means for neutralizing the acidic component in the exhaust gas, a neutralizing agent and a drug introduction part 2 for introducing the chemical into the exhaust gas introduction flow path La are provided. Examples of the drug include calcium-based, sodium-based, and potassium-based drugs, and examples thereof include calcium hydroxide (slaked lime), sodium hydrogen carbonate (sodium bicarbonate), sodium carbonate, and potassium carbonate, with calcium hydroxide being particularly preferable. Neutralized by spraying chemicals (slaked lime) on acidic gas components such as SOx in the exhaust gas, and collected by the dust collector 3. The average particle size of the drug is preferably 5 μm to 10 μm. Hereinafter, the case where slaked lime is used will be described as an example.

In the dust collector 3 provided on the downstream side of the drug introduction unit 2, not only dust in the exhaust gas but also calcium sulfate, calcium sulfite, and the like, which are reaction products generated by the neutralization reaction, are generated by moisture. Agglomerates are also dedusted. As a result, the load on the downstream denitration catalyst device 1 can be reduced. At the time of regeneration of the denitration catalyst, not only the reaction product of SOx and slaked lime, but also a part of NH _{3 in} the regeneration gas reacts with SOx, and becomes acidic ammonium sulfate again and is collected by the bag filter. The collected dust containing the reaction product is preferably recycled to the drug introduction unit 2 as much as possible. As the dust collector 3, a pulse filter such as a pulse jet type or a backwash type (filter type filter), an electric dust collector, a cyclone type dust collector, or the like can be used.

As the denitration catalyst, an existing supported catalyst or mixed catalyst made of a transition metal oxide catalyst such as a V ₂ O ₅ —TiO ₂ catalyst, a platinum group oxidation catalyst, or a combination of these is used. can do. For example, a catalyst containing vanadium pentoxide, tungsten trioxide, molybdenum oxide or the like using titanium oxide as a carrier. The shape of the catalyst is not particularly limited, and any shape such as a granular shape, a pellet shape, or a honeycomb shape can be used. It is preferable to select a honeycomb shape or a pellet shape in consideration of the pressure loss, the flow rate and flow rate of the introduced exhaust gas, the efficiency of the catalytic reaction, and the like.

  The heating temperature in the circulation system of the regeneration gas is preferably controlled so as to be 350 ° C. to 500 ° C. which is a temperature required for regeneration by decomposing acidic ammonium sulfate as a poisonous substance in the catalyst portion. When the temperature of the regeneration gas is less than 350 ° C., the regeneration efficiency of the denitration catalyst is lowered, which is not preferable. Further, in this apparatus, the heater 4 is clearly shown in order to clarify the function, but it is also possible to heat and keep the entire outer periphery of the regeneration gas flow path Lr with a band heater, steam or the like.

  The fan 5 forms a regeneration gas circulation system and feeds the regeneration gas to the regeneration gas processing system.

NH ₃ remaining without being removed by the drug introduction unit 2 and the dust collector 3 is removed by the ammonia removing device 6 at the subsequent stage, and the purified gas is discharged. Examples of the ammonia removing device 6 include an apparatus using an activated carbon adsorption layer, a catalyst (such as a three-way catalyst) for decomposing NH ₃ , or a wet scrubber.

  In addition, there are a pressure gauge for monitoring the pressure in the regenerative gas circulation system, a thermometer for monitoring the internal temperature of the denitration catalyst device 6 and adjusting it within the appropriate catalyst temperature (including regeneration) range, etc. Provided.

[Other configuration examples of this device]
Another embodiment of the present apparatus is shown in FIG. 2 (second configuration example). The downstream side of the ammonia removal device 6 in the bypass passage Lt and the regeneration gas passage Lr are connected to the downstream side of the denitration catalyst device 1, and a part of the regeneration gas after the ammonia removal treatment is introduced into the regeneration gas circulation system. It is characterized by that. In the above description, the case where the regenerated gas finally processed by the ammonia removing device 6 is discharged as it is into the atmosphere through, for example, a chimney is exemplified. However, such purified regenerated gas is denitrated again. It can be used as a regeneration gas for the catalyst circulation system. The regeneration function of the catalyst increases as the poisoning substance in the regeneration gas decreases, and the purified regeneration gas sufficiently satisfies these conditions. That is, in the second configuration example, it is possible to connect the regeneration gas circulation system and the regeneration gas processing system bidirectionally, and to effectively use such purified regeneration gas.

  Specifically, a part of the gas supplied from the ammonia removing device 6 (hereinafter referred to as “recirculation gas”) is introduced into the regeneration gas flow path Lr via the recirculation gas flow path Lu. At this time, the flow rate of the introduced recirculation gas is controlled by the flow rate adjustment damper D2 provided in the recirculation gas flow channel Lu.

<Regeneration method of denitration catalyst using this device>
Next, the regeneration process of the denitration catalyst using this apparatus will be described in detail. During operation of the combustion facility and the exhaust gas treatment device, as shown in FIG. 1A, the dampers V1 to V5 are closed, and the exhaust gas from the combustion facility is caused by the chemical introduced from the chemical introduction unit 2. Neutralization treatment, dust removal treatment by the dust collector 3 and denitration treatment by the denitration catalyst device 1 are performed, and the purified gas is supplied. This system forms a circulation system that heats a part of the gas in the exhaust gas treatment system to a temperature higher than the operating temperature of the denitration catalyst and circulates it as a regenerated gas to the denitration catalyst device when the combustion facility is stopped. A part of the regeneration gas is taken out, neutralization treatment and dust removal treatment are performed, and ammonia removal treatment in the regeneration gas is further performed. Hereinafter, a description will be given based on the first configuration example of FIG.

(1) Stopping the combustion facility The regeneration of the denitration catalyst in this device is usually performed when the combustion facility is stopped during regular or temporary stoppages or periodic inspections. At this time, as shown in FIG. 1B, the present apparatus shuts off the exhaust gas flow passage Lo with the damper Va and opens the closed dampers V1 to V5, thereby regenerating the denitration catalyst. It is possible to prepare for the formation of a regeneration gas circulation system and a regeneration gas processing system necessary for the above.

(2) Formation of regeneration gas circulation system In FIG. 1 (B), the dampers Vc and Vd are closed, the supply flow path Lb of the dust collector 3 and the introduction flow path Lc to the denitration catalyst apparatus 1 are shut off, The supply flow path Ld and the discharge flow path Le of the denitration catalyst device 1 are shut off. At the same time, by operating the heater 4 and the fan 5 provided in the regeneration gas passage Lr, the regeneration gas (remaining exhaust gas) delivered from the denitration catalyst device 1 is supplied from the delivery passage Ld to the regeneration gas passage. A circulation system that is introduced again into the denitration catalyst device 1 is formed via Lr and the introduction flow path Lc. At this time, the flow rate adjustment damper D1 is closed. The regeneration gas heated by the heater 4 gradually decomposes acidic ammonium sulfate, ammonium chloride, and the like that have poisoned the surface of the denitration catalyst, and circulates along with SOx, HCL, or NH ₃ desorbed from the catalyst surface. . Usually, the regeneration gas is preferably circulated at a temperature of about 350 to 500 ° C.

(3) Formation of regenerative gas treatment system If the chemical introduction unit 2 and the dust collector 3 are in a stopped state when the combustion facility is stopped, they are operated together with the ammonia removing device 6 in advance. After such preparation, when the regeneration gas circulation system is formed and poisonous substances start to be desorbed from the surface of the denitration catalyst after a predetermined time has elapsed, the flow rate adjustment damper D1 is opened and the fan 5 is pumped. The regenerated gas is introduced into the processing gas flow path Ls to form a regenerating gas processing system. At this time, since it is necessary to feed a part of the regeneration gas to the regeneration gas processing system, the regeneration gas in the circulation system is reduced, so clean air is sucked into the circulation system. The air intake amount is adjusted by the damper V6.

Specifically, the flow rate adjustment damper D1 sets and controls the flow rate of the regeneration gas introduced through the processing gas flow path Ls, and introduces it into the introduction flow path La. The introduced regeneration gas removes the accompanying acidic components such as SOx and HCL in the introduction flow path La by a neutralization reaction with a chemical such as slaked lime introduced from the chemical introduction section 2, and a minute amount generated by the reaction. Particle reaction products and the like are removed in the dust collector 3. The regeneration gas is guided to the bypass flow path Lt by the damper Vc through the supply flow path Lb, and the accompanying components such as NH ₃ are removed by the adsorption or water washing in the ammonia removal device 6. The regeneration gas purified by such treatment is discharged from the discharge flow path Le. Usually, the regeneration gas is preferably treated at a temperature of about 350 to 500 ° C. By mixing clean air with the regeneration gas, a gas temperature suitable for processing in the dust collector 3 is obtained. The amount of air mixed is adjusted by the damper V7.

  In the second configuration example of the present apparatus, as shown in FIG. 2, the recirculation gas processing system is opened by opening the flow rate adjustment damper D2 provided in the recirculation gas passage Lu branched from the bypass passage Lt. Form. That is, the purified regeneration gas is discharged from the discharge passage Le, and a part thereof is sucked into the regeneration gas passage Lr as the recirculation gas via the recirculation gas passage Lu, and the denitration catalyst. The reproduction efficiency can be improved. The suction flow rate of the recirculation gas is set and controlled by the flow rate adjustment damper D2.

  Further, it is preferable to control the suction of the recirculated gas in accordance with the pressure P inside the regeneration gas flow path Lr, and several control methods can be mentioned. That is, (i) by introducing a recirculation gas when the pressure P drops below a predetermined value, an efficient replacement of the regeneration gas and the cleaning gas by repeated pressure fluctuations and introduction of the cleaning gas at low pressure Can be achieved. (Ii) By introducing the recirculation gas so that the pressure P falls within a predetermined range, steady desorption of SOx and the like from the surface of the denitration catalyst can be achieved, and a stable regeneration gas treatment system can be secured.

  Through the above regeneration process, it is possible to perform a highly efficient denitration catalyst regeneration process in a self-contained manner without removing the denitration catalyst from the denitration catalyst device 1. Further, the denitration catalyst regenerated in this way is less likely to deteriorate after the regeneration, and can be used and regenerated repeatedly.

<Exhaust gas treatment apparatus using a denitration catalyst regeneration method or regeneration apparatus according to the present invention>
Next, FIG. 3 shows an example in which the exhaust gas treatment apparatus 10 using the denitration catalyst regeneration method or regeneration apparatus according to the present invention is an incinerator 20 as a combustion facility. The exhaust gas discharged from the incinerator 20 is introduced into the exhaust gas treatment device 10 through the waste heat boiler 30 and the temperature reduction tower 40, cleaned, and then discharged from the chimney 50. At this time, the exhaust gas treatment device 10 is provided with a denitration catalyst device that removes nitrogen oxides in the exhaust gas discharged from the incinerator 20 to render the exhaust gas harmless, and regenerates the denitration catalyst incorporated therein. Therefore, the playback method or playback device described above is used.

  That is, about 1000 to 1500 ° C. exhaust gas discharged from the incinerator 20 is heat-recovered so that the temperature of the exhaust gas becomes 300 to 350 ° C. as a power source of the waste heat boiler 30. The exhaust gas that has been rapidly cooled to 200 ° C. or less and whose temperature has been adjusted is introduced into the exhaust gas treatment apparatus 10 to perform neutralization treatment, dust removal treatment, and denitration treatment. The temperature reducing tower 40 can be effectively cooled by using circulating water. In this way, by maintaining and ensuring the denitration function of the denitration catalyst device, it is possible to configure an exhaust gas treatment device that can efficiently treat exhaust gas even at the installation site.

Explanatory drawing which shows the reproduction | regeneration apparatus of the denitration catalyst which concerns on one Embodiment of this invention. Explanatory drawing which shows the 2nd structural example of the reproduction | regeneration apparatus of the denitration catalyst which concerns on this invention. Explanatory drawing which shows the waste gas processing apparatus using the reproduction | regeneration apparatus of the denitration catalyst which concerns on one Embodiment of this invention Explanatory drawing showing a catalyst regeneration device according to the prior art

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Denitration catalyst apparatus 2 Drug introduction part 3 Dust collector 4 Heater (heating means)
5 Fan (gas feeding means)
6 Ammonia removal device 10 Exhaust gas treatment device D1, D2 Flow rate adjustment damper Lo Exhaust gas flow channel La, Lc Introduction flow channel Lb, Ld Delivery flow channel Le Discharge flow channel Lr Regeneration gas flow channel Ls Process gas flow channel Lt Bypass flow channel Lu Circulating gas flow paths V1 to V5, Va to Vd Damper

Claims (4)

A chemical for neutralizing acid gas components in the exhaust gas generated from the combustion facility is introduced into the exhaust gas, and the fly ash and / or reaction products in the exhaust gas are processed by the dust collector and supplied with ammonia. In the exhaust gas treatment apparatus for denitrating nitrogen oxides in the exhaust gas by the denitration catalyst apparatus, a method for regenerating the denitration catalyst filled in the denitration catalyst apparatus,
When the combustion facility is stopped, a part of the gas in the exhaust gas treatment system is heated to 350 to 500 ° C. to form a circulation system that circulates and supplies the regeneration gas to the denitration catalyst device. A denitration catalyst regeneration method, wherein a part is taken out, neutralization treatment and dust removal treatment are performed, and ammonia removal treatment in the regeneration gas is further performed. A chemical introduction part for introducing into the exhaust gas a chemical for neutralizing the acidic gas component in the exhaust gas generated from the combustion facility, a dust collector for treating fly ash and / or reaction products in the exhaust gas, A denitration catalyst regeneration device filled in the denitration catalyst device in an exhaust gas treatment device comprising ammonia and supplied with a denitration catalyst device for denitration treatment of nitrogen oxides in the exhaust gas,
Closing means for closing the inlet-side flow path and outlet-side flow path of the denitration catalyst device to block the exhaust gas flow channel, and connecting to the exhaust gas flow channels upstream and downstream of the denitration catalyst device blocked by the closing means A regenerative gas flow path, a gas feeding means and a heating means provided in the regenerative gas flow path, and a circulation system is formed, and the introduction flow path to which the drug introduction section is connected and the regenerative gas flow path are connected A processing gas channel, a bypass channel connected from the middle of the dust collector and the inlet side closing means to the downstream side of the outlet side closing means, and an ammonia removal device provided in the bypass channel, The processing system is configured,
A part of the regeneration gas heated while circulating in the circulation system is taken out, introduced into the regeneration gas treatment system through the treatment gas flow path, the neutralization treatment and the dust removal treatment are performed, and the regeneration gas is further removed. A denitration catalyst regenerator that performs ammonia removal treatment therein.   A downstream side of the ammonia removal device in the bypass passage is connected to a downstream side of the denitration catalyst device in the regeneration gas passage, and a part of the regeneration gas after the ammonia removal treatment is introduced into the circulation system. The regeneration device for a denitration catalyst according to claim 2.   An exhaust gas treatment apparatus that exhausts exhaust gas discharged from a combustion facility and introduced through a waste heat boiler, a temperature-decreasing tower, performs neutralization treatment, dust removal treatment and denitration treatment, and discharges it as a purified gas, An exhaust gas treatment apparatus, wherein regeneration treatment of a denitration catalyst filled in a denitration catalyst device for performing denitration treatment is performed using the regeneration method according to claim 1 or the regeneration device according to claim 2 or 3.

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