JP4266267B2 - Exhaust gas treatment method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an exhaust gas treatment method and apparatus for performing desulfurization / denitration, and more particularly to an exhaust gas treatment method and apparatus using a cross-flow moving bed reactor using a carbonaceous catalyst.
[0002]
[Prior art]
A desulfurization and denitration method is known in which sulfur oxides (SOx) and nitrogen oxides (NOx) contained in exhaust gas are treated using a carbonaceous catalyst (which also functions as an adsorbent) such as activated carbon. In this desulfurization and denitration method, sulfur oxides in exhaust gas are adsorbed as sulfuric acid on the carbonaceous catalyst, and are further adsorbed and removed by changing to ammonium salt of sulfuric acid by reaction with added ammonia. On the other hand, nitrogen oxides are decomposed and removed by reaction with ammonia added to the exhaust gas.
[0003]
[Problems to be solved by the invention]
Since the carbonaceous catalyst is inactivated along with the adsorption of sulfuric acid and ammonium salt, heating regeneration is required. At this time, when the molar ratio of ammonia and SO ₂ present on the carbonaceous catalyst (NH ₃ / SO ₂ : actually NH ₄ ⁺ / SO ₄ ²⁻ ) increases, the decomposition rate of ammonia in the regenerator decreases, As a result, a large amount of ammonia is mixed in the high-concentration SO ₂ to be recovered, resulting in problems such as blockage of the apparatus in the by-product recovery process and a decrease in recovered product purity. Further, in a gas washing step such as washing with water, it is necessary to dissolve it in wastewater as an ammonium salt (ammonium sulfite or the like). In addition, when the exhaust gas temperature is low (about 100 ° C. or lower), the ammonium sulfate salt produced on the carbonaceous catalyst may break down the pores of the catalyst, resulting in low-temperature fracture that powders. In order to improve the denitration performance, these problems become more prominent as the amount of ammonia added is increased.
[0004]
In view of the above problems, the present invention is an exhaust gas by a cross-flow moving bed reactor capable of ensuring a desulfurization / denitration rate while keeping the NH ₃ / SO ₂ ratio on the carbonaceous catalyst after adsorption treatment low. It is an object to provide a processing method and apparatus.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problems, an exhaust gas treatment method according to the present invention includes (1) a step of adding ammonia to at least a part of exhaust gas to be treated, and (2) a first direct treatment of exhaust gas with and without addition of ammonia. A first treatment step that leads to an alternating-current moving bed reactor, and (3) guides at least a portion of the treated exhaust gas from the first treatment step to a second cross-flow moving bed reactor for treatment. A second treatment step, (4) heating the used carbonaceous catalyst in an inert gas to recover sulfur oxides and regenerating the carbonaceous catalyst, and (5) regenerated carbon. Returning the catalyst to each cross-flow moving bed reactor and circulating and reusing it, and (6) part of the sulfur oxide recovered in the regeneration step is led to the second cross-flow moving bed reactor And a step of mixing with exhaust gas.
[0006]
On the other hand, in the exhaust gas treatment apparatus according to the present invention, (1) a moving bed is formed by vertically flowing the carbonaceous catalyst filled in the interior, and the moving bed and the introduced exhaust gas are brought into contact with each other in a cross flow. First and second cross-flow moving bed reactors for treating exhaust gas, and (2) an addition device for adding ammonia to at least a part of the exhaust gas led to the first cross-flow moving bed reactor; 3) Exhaust gas transfer means for guiding at least part of the exhaust gas that has passed through the first cross-flow moving bed reactor to the second cross-flow moving bed reactor, and (4) no carbonaceous catalyst after use. A regenerator that regenerates the carbonaceous catalyst by recovering sulfur oxides by heating in active gas, and (5) carbon that is recirculated and reused by returning the regenerated carbonaceous catalyst to each cross-flow moving bed reactor. And a part of the sulfur oxide recovered by the regenerator to the second cross-flow moving bed reactor Characterized in that it comprises a sulfur oxide returning means for mixing Karel exhaust gas, a.
[0007]
According to the exhaust gas treatment apparatus and method according to the present invention, ammonia is added to a part of the exhaust gas and is led to the first cross-flow moving bed reactor for treatment, so that most of SOx is adsorbed on the carbonaceous catalyst. The denitration process is performed by a catalytic reaction between ammonia and NOx. Here, if the amount of ammonia injected is increased to increase the denitration performance, the amount of ammonia leaking into the processing gas will increase. However, the second cross-flow transfer is performed by adding SOx recovered by the regenerator to a part of the processing gas. By passing through the bed reactor, leaked ammonia and added SOx are adsorbed and removed by the carbonaceous catalyst. Thereby, the NH ₃ / SO ₂ ratio adsorbed on the carbonaceous catalyst is kept low, and the decomposition rate of ammonia during regeneration in the regenerator is improved. And it becomes easy to increase the injection quantity of ammonia, and it becomes possible to improve denitration performance.
[0008]
In the circulation reuse process of the exhaust gas treatment method according to the present invention, the carbonaceous catalyst after regeneration is guided to the first cross-flow moving bed reactor, and the carbonaceous gas discharged from the first cross-flow moving bed reactor is used. It is preferred to direct the catalyst to a second cross-flow moving bed reactor. On the other hand, the carbonaceous catalyst circulation means of the exhaust gas treatment apparatus according to the present invention includes a carbonaceous catalyst return means for introducing the regenerated carbonaceous catalyst into the first cross-flow moving bed reactor, and a first cross-flow transfer. A carbonaceous catalyst transfer means for introducing the carbonaceous catalyst discharged from the layered reactor into the second cross-flow moving bed reactor, and a carbonaceous catalyst discharged from the second cross-flow moving bed reactor. It is preferable to include a carbonaceous catalyst discharging means that leads to the regenerator.
[0009]
Thus, by passing the carbonaceous catalyst in the order of the first reactor → the second reactor, it is possible to effectively use the carbonaceous catalyst while ensuring the desulfurization and denitration performance in the first reactor. it can.
[0010]
Alternatively, the regeneration step of the exhaust gas treatment method according to the present invention is a step of mixing and regenerating the carbonaceous catalyst discharged from each of the first and second cross-flow moving bed reactors, and a circulation reuse step The carbonaceous catalyst after regeneration is preferably divided into two and introduced into each of the first and second cross-flow moving bed reactors. On the other hand, the carbonaceous catalyst circulation means of the exhaust gas treatment apparatus according to the present invention bisects the regenerated carbonaceous catalyst and introduces it into each of the first and second cross-flow moving bed reactors. And carbonaceous catalyst discharge means for guiding the carbonaceous catalyst discharged from each of the first and second cross-flow moving bed reactors to the same regenerator.
[0011]
In this way, it is easy to independently adjust the flow rate of the moving bed and the residence time of the carbonaceous catalyst in each of the first and second reactors, while using the regenerator as a whole. Becomes compact.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same reference numerals are given to the same components in the drawings as much as possible, and duplicate descriptions are omitted.
[0013]
FIG. 1 is a schematic view showing a first embodiment of an exhaust gas treatment apparatus according to the present invention. This apparatus includes cross-flow moving bed reactors 10 and 20, a heating regenerator 30, a washing tower 40, a separator 50, and an ammonia supply device 60.
[0014]
Each of the reactors 10 and 20 is filled with a carbonaceous catalyst such as activated carbon, and the moving beds 11 and 21 are formed by descending in a vertical direction at a predetermined speed. Control of the amount of carbonaceous catalyst introduced into the reactor 10 (20) and the amount of withdrawal by the introduction valve 12 (22) provided at the top of the reactor 10 (20) and the extraction valve 13 (23) provided at the bottom. Thus, the flow rate of the moving bed 11 (21) can be adjusted. Hereinafter, the upstream side and the downstream side are referred to in accordance with the flow direction of the moving bed 11 (21).
[0015]
The treated exhaust gas has a structure that is introduced so as to be orthogonal to the flow directions of the carbonaceous catalysts of the reactors 10 and 20. The inlet side of the reactor 10 (20) is provided with a gas inlet 14 (24) and an inlet louver 15 (25) for introducing gas and preventing the carbonaceous catalyst from flowing out from the moving bed 11 (21). On the opposite outlet side, a perforated plate 16 (26) and a gas outlet 17 (27) are provided.
[0016]
The line L1 for supplying the treatment target exhaust gas whose temperature is adjusted to 60 to 180 ° C. is connected to the gas inlet 14 of the first reactor 10, but is connected to the ammonia supply device 60 in the middle thereof. Line L2 is connected. The line L3 connects the gas outlet 17 of the first reactor 10 and the gas inlet 24 of the second reactor 20. The gas outlet 27 of the second reactor 20 is connected to a subsequent processing facility via a line L4.
[0017]
The drawing valve 13 at the lower part of the first reactor 10 is connected to the charging valve 22 at the upper part of the second reactor 20 via a line L13. On the other hand, the drawing valve 23 at the lower part of the second reactor 20 is connected to the introduction port of the carbonaceous catalyst of the heating regenerator 30 via the line L10. The carbonaceous catalyst outlet of the heating regenerator 30 is connected to a separator 50 via a line L11, and the separator 50 is further connected to a charging valve 12 at the top of the first reactor 10 via a line L12. It is connected to circulate the carbonaceous catalyst.
[0018]
The desorbed gas discharge port of the heating regenerator 30 is connected to the cleaning tower 40 via a line L20, and the desorbed gas that has passed through the cleaning tower 40 is branched into lines L21 and L22. The line L21 is connected to a by-product recovery device (not shown), and the line L22 is connected to a line L3 that sends exhaust gas from the first reactor 10 to the second reactor 20.
[0019]
Next, the operation of the present embodiment, that is, the exhaust gas treatment method according to the present invention will be described in detail. The exhaust gas supplied from the line L1 is injected and mixed with ammonia from the ammonia supply device 60 via the line L2. This gas is guided into the first reactor 10 via the gas inlet 14, passes through the inlet louver 15, and is brought into contact with the moving bed 11 inside the reactor 10. As described above, the descending speed of the moving bed 11 inside the first reactor 10 is adjusted mainly by adjusting the amount of the carbonaceous catalyst extracted from the valve 13.
[0020]
Here, SOx in the exhaust gas is adsorbed and removed as sulfuric acid by the following reaction by contact with the carbonaceous catalyst.
[0021]
SO ₂ + 1 / 2O ₂ + H ₂ O → H ₂ SO ₄ (1)
SO ₃ + H ₂ O → H ₂ SO ₄ … (2)
Part of the ammonia mixed in the exhaust gas reacts with this sulfuric acid as follows to produce acidic ammonium sulfate and ammonium sulfate.
[0022]
H ₂ SO ₄ + NH ₃ → NH ₄ HSO ₄ … (3)
NH ₄ HSO ₄ + NH ₃ → (NH ₄ ) ₂ SO ₄ … (4)
When the amount of sulfuric acid is large, ammonium sulfate is further decomposed into acidic ammonium sulfate by the following reaction.
[0023]
(NH ₄ ) ₂ SO ₄ + H ₂ SO ₄ → 2NH ₄ HSO ₄ … (5)
On the other hand, NOx in the exhaust gas is decomposed by reacting with ammonia as follows using a carbonaceous catalyst as a catalyst.
[0024]
4NH ₃ + 4NO + O ₂ → 4N ₂ + 6H ₂ O… (6)
On the side close to the gas inlet 14 of the moving bed 11, NH ₃ and sulfuric acid are adsorbed on the carbonaceous catalyst, and ammonium sulfate is generated. Then, NH ₃ and sulfuric acid are adsorbed as acidic ammonium sulfate in the region on the exhaust gas outlet side. In regions after SOx is almost removed in these zones, denitration is performed by the remaining NH ₃ . Therefore, in consideration of the amount of ammonia consumed by the neutralization reaction of sulfuric acid, it is necessary to introduce the ammonia supplied via the line L2 so as to be larger than the sum of the molar amounts of NOx and SOx in the exhaust gas. The exhaust gas thus denitrated is sent from the exhaust gas outlet 17 to the second reactor 20 via the line L3.
[0025]
In this way, the exhaust gas sent to the second reactor 20 via the line L3 is mixed with SO ₂ recovered by the regenerator 30 via the line L22. Also in the second reactor 20, the descending speed of the moving bed 21 inside is adjusted mainly by adjusting the amount of carbonaceous catalyst withdrawn from the valve 23. Here By first SO ₂ concentration of the gas of SO ₂ after the addition than the concentration of ammonia remaining without contributing to the reaction in the reactor 10 is to set the amount to be higher, in the moving bed 22 Is mainly the adsorption reaction of sulfuric acid. The remaining ammonia is adsorbed and removed by a chemical reaction represented by the equations (3) to (5). Further, since the denitration reaction is further performed in the second reactor 20 by the unreacted unadsorbed ammonia, the denitration rate is improved. Further, since the exhaust gas containing ammonia is passed through the second reactor 20 for processing, the amount of leaked ammonia can be reduced. Therefore, the amount of ammonia added via the line L2 can be increased, so that the denitration rate in the first reactor 10 can also be improved. The exhaust gas thus desulfurized and denitrated is sent to the subsequent processing facility via the line L4.
[0026]
The carbonaceous catalyst in the moving bed 11 subjected to the exhaust gas treatment in the first reactor 10 is pulled by a predetermined amount from the bottom valve 13 to the second reactor 20 via the line L13 and the charging valve 22. Sent. The carbonaceous catalyst of the moving bed 21 that has been further subjected to exhaust gas treatment in the second reactor 20 is pulled by a predetermined amount from the bottom valve 23 and sent to the regenerator 30 via the line L10. In the regenerator 30, the carbonaceous catalyst is regenerated by heating in a high-temperature inert gas atmosphere at about 300 to 600 ° C. Then, the regenerated carbonaceous catalyst is sent to the separator 50 made of a vibrating screen or the like via the line L11, and after the dust and the pulverized carbonaceous catalyst are removed, the first reactor 10 is line L12. It is returned to the moving bed 11 through a charging valve 12 provided at the upper part of the gas and reused.
[0027]
In the carbonaceous catalyst withdrawn from the lower part of the second reactor 20, most of NH ₃ is adsorbed as acidic ammonium sulfate that is more easily decomposed than ammonium sulfate, and the NH ₃ / SO ₂ ratio is also set to 0. It is reduced to about 7-1. Therefore, the ratio of NH ₃ present in the desorbed gas can be greatly reduced, and the regeneration process of SO ₂ contained in the desorbed gas at a high concentration is facilitated. Further, when heat regeneration is performed in a state where a large amount of sulfuric acid and ammonia are present on the carbonaceous catalyst, there is an effect of increasing the activity of the carbonaceous catalyst.
[0028]
The desorbed gas generated in the regenerator 30 is sent to the washing tower 40 via the line L20, and is generated by being washed with water, and most of it is sent to the byproduct recovery process via the line L21. A part of the desorbed gas (mostly SO ₂ ) is mixed with the exhaust gas flowing through the line L3 via the line L22. Here, the amount of SO ₂ returned through the line L22 is adjusted so that the adsorption NH ₃ / SO ₂ ratio of the carbonaceous catalyst drawn out from the lower part of the second reactor 20 is about 0.7 to 1. is doing. The SO ₂ return line L22 may be provided so as to connect the regenerator 30 and the line L3.
[0029]
Subsequently, second to fourth embodiments of the exhaust gas treatment apparatus according to the present invention will be described with reference to FIGS. In the processing apparatus 1a of the second embodiment shown in FIG. 2, only a part of the gas processed in the first reactor 10 (here, the gas discharged from the upstream outlet 17u) is supplied to the second reactor. The second embodiment is different from the first embodiment in that it is sent to 20, and the remainder (here, the gas discharged from the outlet 17l on the downstream side) is sent to the subsequent processing apparatus as it is via the line L5.
[0030]
In this apparatus 1a, only a part of the gas processed in the first reactor 10 is sent to the second reactor 20, but the process is performed when the amount of leaked ammonia is smaller than that in the apparatus 1 of the first embodiment. The device can be made compact. The ratio of the exhaust gas sent to the second reactor 20 in the exhaust gas treated in the first reactor 10 is appropriately determined according to the target value of the amount of leaked ammonia.
[0031]
The processing apparatus 1b of the third embodiment shown in FIG. 3 bisects the inlet of the first reactor 10 and adds ammonia to only one exhaust gas (here, supplied upstream). I am doing so. That is, the first reactor 10 has an upstream side exhaust gas inlet 14u and a downstream side exhaust gas inlet 14l. The exhaust gas mixed with ammonia via the line L2 enters the line L1 into the exhaust gas inlet 14u. The exhaust gas not mixed with ammonia is introduced into the exhaust gas inlet 14l via the line L6.
[0032]
In this apparatus 1b, ammonia is not mixed in the exhaust gas introduced into the lower part of the first reactor, so the denitration reaction does not proceed in this region, but the denitration reaction proceeds by the ammonia remaining in the second reactor. Therefore, the same effect can be obtained.
[0033]
The processing apparatus 1c of the fourth embodiment shown in FIG. 4 differs from the processing apparatus 1 of the first embodiment shown in FIG. 1 only in the circulation line of the carbonaceous catalyst. Specifically, while the processing apparatus 1 was sending the carbonaceous catalyst from the first reactor 10 to the second reactor 20, in the processing apparatus 1c, the first reactor 10, The carbonaceous catalyst discharged from the second reactor 20 is directly sent to the regenerator 30 via the lines L14 and L10. Then, after regeneration, the regenerated activated carbon from which unnecessary components have been removed by the separator 50 is returned to the first reactor 10 and the second reactor 20 via lines L12 and L15.
[0034]
In this apparatus 1c, since the carbonaceous catalyst not adsorbed with SO ₂ is supplied to the second reactor, the amount of SO ₂ to be returned via the line L22 is removed from the apparatus 1 in order to efficiently remove leaked ammonia. The effect similar to that of the device 1 can be obtained. On the other hand, it is easier to independently adjust the flow rate of the moving bed and the residence time of the carbonaceous catalyst in the first reactor 10 and the second reactor 20 compared to the first to third embodiments. There is an advantage of becoming.
[0035]
As the carbonaceous catalyst of the present invention, activated carbon, activated coke, activated char, etc. obtained by activating coal, etc. with oxidation treatment, heat treatment or steam, etc. are generally used, such as vanadium, iron, manganese, etc. It is also possible to use a material in which the metal compound is supported. The ammonia supply device may inject ammonia water or the like in addition to ammonia gas.
[0036]
【Example】
The present inventors conducted a comparative experiment for confirming the effect of the exhaust gas treatment method of the present invention. Hereinafter, the experimental result will be described.
[0037]
EXAMPLE Using the treatment apparatus shown in FIG. 1, an exhaust gas of 1000 m ³ / h (Normal) at 140 ° C. containing 150 ppm SOx, 220 ppm NOx, 10% moisture, and 15% oxygen was treated. The amount of ammonia added via the line L2 was set so that the concentration in the exhaust gas after the addition was 450 ppm. The carbonaceous catalyst is activated carbon having a diameter of about 7 mm and a length of about 8 mm. The first reactor 10 is charged with 2.50 m ³ and the second reactor 20 is charged with 1.25 m ^3, and the residence times are 120 hours and 60 hours, respectively. The withdrawal amount and the input amount were adjusted so that And the desorption gas supply amount through the line L22 was adjusted so that the SO ₂ concentration of the exhaust gas introduced into the second reactor 20 would be 190 ppm.
[0038]
As a result, the desulfurization rate in the first reactor 10 was almost 100%, the denitration rate was 82%, and the NH ₃ concentration in the exhaust gas after passing was 49 ppm. The desulfurization rate in the second reactor 20 was almost 100%, the denitration rate was 3%, and the NH ₃ concentration in the exhaust gas after passing was 2 ppm. That is, the desulfurization rate in the entire apparatus 1 was almost 100%, the denitration rate was 82.5%, and the leak NH ₃ concentration was 2 ppm. The ammonia decomposition rate in the regenerator 30 was 96%.
[0039]
Comparative Example In the treatment apparatus of FIG. 1, the same exhaust gas treatment as in the example was performed without returning the desorbed gas from the line L22. All other conditions are the same as in the examples.
[0040]
As a result, the desulfurization rate in the first reactor 10 was almost 100%, the denitration rate was 81%, and the NH ₃ concentration in the exhaust gas after passing was 51 ppm. The denitration rate in the second reactor 20 was 6%, and the NH ₃ concentration in the exhaust gas after passing was 4 ppm. That is, the desulfurization rate of the entire apparatus 1 was almost 100%, the denitration rate was 82%, and the leak NH ₃ concentration was 4 ppm. The ammonia decomposition rate in the regenerator 30 was 45%.
[0041]
As a result, the exhaust gas treatment apparatus and method of the present invention reduces the ammonia amount leaked into the exhaust gas while maintaining the denitration rate, thereby reducing the NH ₃ / SO ₂ ratio adsorbed on the activated carbon, and the ammonia decomposition rate The effect which improves is confirmed. Since the amount of leaked ammonia is reduced, the NOx removal rate can be further improved by further injecting ammonia.
[0042]
The exhaust gas treatment apparatus and method of the present invention can be suitably applied to treatment of exhaust gas containing harmful substances such as SOx, NOx, dioxin, and Hg such as boiler exhaust gas, sintered exhaust gas, and waste incinerator exhaust gas.
[0043]
【The invention's effect】
As described above, according to the present invention, by adding a desorbed gas containing SO ₂ to a part of the exhaust gas desulfurized and denitrated in the first reactor and introducing it to the second reactor, the leaked ammonia can be reduced. Can be removed efficiently. Therefore, the amount of ammonia added to the exhaust gas leading to the first reactor can be increased to improve the denitration rate.
[Brief description of the drawings]
FIG. 1 is an overall schematic view showing a first embodiment of an exhaust gas treatment apparatus according to the present invention.
FIG. 2 is an overall schematic view showing a second embodiment of the exhaust gas treatment apparatus according to the present invention.
FIG. 3 is an overall schematic view showing a third embodiment of the exhaust gas treatment apparatus according to the present invention.
FIG. 4 is an overall schematic view showing a fourth embodiment of the exhaust gas treatment apparatus according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10, 20 ... Cross-flow moving bed reactor, 11, 21 ... Moving bed, 12, 13, 22, 23 ... Valve, 14, 24 ... Exhaust gas inlet, 17, 27 ... Exhaust gas outlet, 30 ... Regenerator, 40 ... Separation 50, cleaning tower, 60 ... ammonia supply device, L1-L6 ... gas piping, L10-L15 ... carbonaceous catalyst supply line, L20-L22 ... desorption gas piping.

Claims (6)

In the exhaust gas treatment method in which exhaust gas is brought into contact with the carbonaceous catalyst in the cross-flow moving bed reactor and desulfurized and denitrated,
Adding ammonia to at least part of the exhaust gas to be treated;
Introducing the ammonia added and non-added exhaust gas to the first cross-flow moving bed reactor for treatment;
A step of guiding at least a part of the treated exhaust gas of the first treatment step to the second cross-flow moving bed reactor,
Heating the used carbonaceous catalyst in an inert gas to recover the sulfur oxide to regenerate the carbonaceous catalyst;
Returning the regenerated carbonaceous catalyst to the cross-flow moving bed reactor and recycling it;
Mixing a part of the sulfur oxide recovered in the regeneration step with the exhaust gas led to the second cross-flow moving bed reactor;
An exhaust gas treatment method comprising: In the circulation reuse step, the regenerated carbonaceous catalyst is guided to the first cross-flow moving bed reactor, and the carbonaceous catalyst discharged from the first cross-flow moving bed reactor is supplied to the second cross-flow moving bed reactor. The exhaust gas treatment method according to claim 1, wherein the exhaust gas treatment method is led to a cross-flow moving bed reactor. The regeneration step is a step of mixing and regenerating the carbonaceous catalyst discharged from each of the first and second cross-flow moving bed reactors, and the circulation reuse step is a carbonaceous material after regeneration. The exhaust gas treatment method according to claim 1, wherein the catalyst is divided into two and introduced into each of the first and second cross-flow moving bed reactors. In exhaust gas treatment equipment for desulfurization and denitration treatment by contacting exhaust gas with carbonaceous catalyst,
First and second cross-flow moving beds in which the carbonaceous catalyst filled therein is vertically moved to form a moving bed, and the moving bed is brought into contact with the introduced exhaust gas in a cross-flow to treat the exhaust gas. A reactor,
An addition device for adding ammonia to at least a part of the exhaust gas led to the first cross-flow moving bed reactor;
Exhaust gas transfer means for guiding at least a part of the exhaust gas that has passed through the first cross-flow moving bed reactor to the second cross-flow moving bed reactor;
A regenerator that regenerates the carbonaceous catalyst by heating the used carbonaceous catalyst in an inert gas to recover sulfur oxide;
A carbonaceous catalyst circulation means for recirculating and reusing the regenerated carbonaceous catalyst to each of the cross-flow moving bed reactors;
A sulfur oxide returning means for mixing a part of the sulfur oxide recovered by the regenerator with the exhaust gas led to the second cross-flow moving bed reactor;
An exhaust gas treatment apparatus comprising: The carbonaceous catalyst circulation means includes
Carbonaceous catalyst return means for introducing the regenerated carbonaceous catalyst into the first cross-flow moving bed reactor;
Carbonaceous catalyst transfer means for introducing the carbonaceous catalyst discharged from the first cross-flow moving bed reactor into the second cross-flow moving bed reactor;
Carbonaceous catalyst discharge means for guiding the carbonaceous catalyst discharged from the second cross-flow moving bed reactor to the regenerator;
An exhaust gas treatment apparatus according to claim 4. The carbonaceous catalyst circulation means includes
Carbonaceous catalyst return means for bisecting the regenerated carbonaceous catalyst into each of the first and second cross-flow moving bed reactors;
Carbonaceous catalyst discharge means for guiding the carbonaceous catalyst discharged from each of the first and second cross-flow moving bed reactors to the same regenerator;
An exhaust gas treatment apparatus according to claim 4.

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