KR101832359B1 - Wet exhaust gas cleaning apparatus and method - Google Patents

Abstract

The present invention relates to a wet combustion gas cleaning apparatus and method. According to an embodiment of the present invention, disclosed are the wet combustion gas cleaning apparatus including: a high temperature cleaning unit for removing sulfur trioxide (SO_3) and ammonia (NH_3) in a combustion gas of a first temperature range of 100 degrees centigrade or less by wet cleaning; a temperature control unit for cooling a gas discharged from the high temperature cleaning unit to a second temperature range lower than the first temperature range; and a low temperature cleaning unit for removing sulfur dioxide (SO_2) from a gas discharged from the temperature control unit by wet cleaning, and a cleaning method using the same. Accordingly, the present invention can maximize the removal of sulfur oxides.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flue gas cleaning apparatus,

More particularly, the present invention relates to a flue gas treating system for separating sulfur oxides generated in a combustion process into sulfuric acid (SO ₃ ) with a strong acidity and sulfuric acid (SO ₂ ) (NH ₃ ) as a reducing agent, and a wet cleaning method using the same.

In general, harmful substances such as nitrogen oxides and sulfur oxides are contained in the combustion gas discharged when the energy is obtained by burning the fossil fuel or the waste in the combustion furnace of a factory or a power plant, or an incinerator or an internal combustion engine. A variety of techniques are being used and studied to reduce.

1 is a block diagram of a conventional flue gas treating system equipped with a wet desulfurization facility (FGD). This treatment system removes fine particles and sulfur oxides while passing the combustion gas discharged from the combustion chamber 10 through the denitration unit 20, the dust collector 30, and the desulfurization unit 40. The wet desulfurization apparatus 40 used in this case uses limestone slurry, which requires a large space for the desulfurization reaction, a complicated nozzle should be disposed in the apparatus, and a large amount of process water must be used. Therefore, there is a disadvantage that expensive equipment cost and operation cost are required and a large amount of waste water is generated.

2 is a block diagram of a conventional combustion gas treatment system equipped with an in-furnace desulfurization system. This treatment system is a method of removing sulfur oxides in the furnace by injecting a desulfurizing agent into the combustion chamber 10 together with the fuel, and has a relatively stable removal rate. However, this method is disadvantageous in that it is difficult to apply to a fuel having a high sulfur content and problems such as slagging and fouling occur when the combustion chamber is at a high temperature.

Patent Document 1: Korean Patent Laid-Open Publication No. 2004-0022415 (published on March 12, 2004) Patent Document 2: Korean Patent No. 10-1334935 (registered on Nov. 25, 2013)

According to an embodiment of the present invention, there is provided a wet cleaning apparatus capable of separating sulfur dioxide and sulfur trioxide from each other, thereby maximizing the removal of sulfur oxides and facilitating the water treatment of the cleaning water.

According to an embodiment of the present invention, there is provided a wet scrubber for preventing the ammonia slip phenomenon in which ammonia, which has not been used for denitrification, is discharged to the atmosphere by simultaneously removing sulfur trioxide and ammonia.

According to an embodiment of the present invention, there is provided a wet cleaning apparatus capable of additionally removing fine dust or ultrafine dust that has passed through a dust collecting apparatus at a front end of a system.

According to an embodiment of the present invention, there is provided a wet scrubber for scrubbing a combustion gas, comprising: a high-temperature (high-temperature) scrubber for removing sulfur trioxide (SO ₃ ) and ammonia (NH ₃ ) from a combustion gas in a first temperature range of 100 ° C or less, The three governments; A temperature regulator for cooling the gas discharged from the high temperature cleaning unit to a second temperature range lower than the first temperature range; And a low temperature cleaning unit for removing sulfur dioxide (SO ₂ ) from the gas discharged from the temperature control unit by wet cleaning.

According to an embodiment of the present invention, there is provided a wet cleaning method for cleaning a combustion gas, comprising the steps of: in a first chamber, cleaning sulfur trioxide (SO ₃ ) and ammonia (NH ₃ ) from a combustion gas in a first temperature range, Lt; RTI ID = 0.0 > a < / RTI > Cooling the gas discharged from the first chamber to a second temperature range lower than the first temperature range in the second chamber; And a low temperature cleaning step of removing sulfur dioxide (SO ₂ ) from the gas discharged from the second chamber by a wet cleaning in the third chamber and the second chamber.

According to one embodiment of the present invention, there is an advantage that sulfur oxide is separated and removed by strongly acidic sulfuric acid and slightly acidic sulfuric acid to maximize removal of sulfuric acid and facilitate water treatment of cleaning water.

According to an embodiment of the present invention, the ammonia can be removed by reacting with ammonia during the removal of sulfur trioxide, so that the excess ammonia discharged from the denitration unit at the front end, which is not used for nitrogen oxide removal, can be removed from the wet scrubber, There is an advantage to be able to.

According to an embodiment of the present invention, fine dust or ultrafine dust may be additionally removed by wet cleaning of the high-temperature cleaning section and the low-temperature cleaning section, thereby further enhancing the dust collection effect of the combustion gas processing system.

1 is a block diagram of a conventional flue gas treating system equipped with a wet desulfurization facility (FGD)
2 is a block diagram of a conventional combustion gas processing system equipped with an in-
3 is a block diagram of a first flue gas treating system to which a flue gas wet scrubber is applied in accordance with an embodiment of the present invention.
4 is a block diagram of a second combustion gas processing system to which a combustion gas wet scrubber is applied in accordance with an embodiment of the present invention;
5 is a block diagram of a combustion gas wet scrubber according to one embodiment,
6 is a view for explaining an exemplary apparatus configuration of a combustion gas wet scrubber according to an embodiment,
7 is a view for explaining an exemplary configuration of the channel unit 116 according to an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, and advantages of the present invention will become more readily apparent from the following description of preferred embodiments with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that the disclosure can be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

Where the terms first, second, etc. are used herein to describe components, these components should not be limited by such terms. These terms have only been used to distinguish one component from another. The embodiments described and exemplified herein also include their complementary embodiments.

In this specification, the singular forms of nouns or pronouns include plural forms unless the context clearly dictates otherwise. The terms "comprise" and / or "comprising" used in the specification do not exclude the presence or addition of one or more other elements.

Hereinafter, the present invention will be described in detail with reference to the drawings. In describing the specific embodiments below, various specific details have been set forth in order to explain the invention in greater detail and to assist in understanding it. However, it will be appreciated by those skilled in the art that the present invention may be understood by those skilled in the art without departing from such specific details. In some cases, it should be mentioned in advance that it is common knowledge in describing an invention that parts not significantly related to the invention are not described in order to avoid confusion in explaining the present invention.

3 is a block diagram of a first flue gas treating system to which a flue gas wet scrubber is applied in accordance with an embodiment of the present invention. Referring to the drawings, a first combustion gas treatment system includes a combustion chamber 10, a denitration unit 20, an acid gas cleaning unit 25, a dust collecting unit 30, a wet scrubber 100 and a stack 50 .

The combustion chamber 10 may burn a fuel source such as fossil fuel, biomass, or waste, and use incineration heat generated at this time as an energy source, for example, a waste treatment system or a power generation system. The combustion gas generated in the combustion chamber 10 can be discharged to the outside through the denitration unit 20, the acidic gas cleaning unit 25, the dust collecting unit 30, the wet scrubber 100 and the stack 50 .

The denitration unit 20 is a unit for removing nitrogen oxides (NOx) contained in the combustion gas. As a representative reduction method of currently known nitrogen oxides, selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) are available. In one embodiment, the denitration unit 20 may be an SNCR or SCR type denitration unit. The denitration unit 20 may use ammonia water or urea water as a reducing agent to remove nitrogen oxides in the combustion gas.

When ammonia (NH3) is used as a reducing agent, only a part of the ammonia introduced into the denitration unit 20 is used for the reduction reaction, so that much more amount (for example, 2 to 3 times as much) as the conventional amount is injected. However, in this case, the ammonia slip phenomenon occurs in which unused ammonia is discharged together with the combustion gas to the downstream end of the apparatus, thereby necessitating a separate process for removing ammonia from the downstream end of the apparatus. However, as will be described later, in the illustrated embodiment, not only sulfur oxides but also ammonia can be removed together in the wet scrubber 100 according to the present invention. Therefore, it is possible to eliminate the ammonia slip phenomenon, ) Can be sufficiently injected with ammonia.

The acid gas scrubbing apparatus 25 is a device for removing sulfur oxides (SOx) in the combustion gas and can be realized by any conventional desulfurization apparatus. For example, the acidic gas scrubbing unit 25 may be implemented in a semi-dry reactor (SDR), and the slurry may be sprayed into the combustion gas to remove sulfur oxides.

The dust collecting device 30 collects and removes foreign matter such as dust from the combustion gas that has passed through the denitration device 20 and the acid gas scrubbing device 25 and removes foreign matter such as dust from the combustion gas through the conventional dust collecting device . ≪ / RTI >

The wet scrubber 100 may be disposed upstream of the stack 50 and may remove residual harmful substances contained in the combustion gas discharged from the dust collector 30. In one embodiment, the wet scrubbing apparatus 100 may remove sulfur oxides (SOx) and ammonia (NH ₃₎ remaining in the combustion gas, it is possible to additionally, hydrogen chloride (HCl) and remove fine dust. The wet scrubber 100 will be described later with reference to Figs. 5 to 7. The combustion gas that has passed through the wet scrubber 100 is discharged to the outside through the stack 50 (e.g., a chimney) as a flue gas.

3, the denitration unit 20, the acidic gas cleaning unit 25, the dust collecting unit 30, the wet scrubber 100, and the stack 50 are provided at the rear end of the combustion chamber 10 But this arrangement is only an exemplary embodiment, and various other various processing units may be added to the rear end of the combustion chamber 10 according to the specific embodiment, or alternatively, the denitration unit 20 ), The acid gas scrubbing apparatus 25, and the dust collecting apparatus 30 may be omitted or the order of arrangement of these devices may be changed.

4 is a block diagram of a second flue gas treating system to which a flue gas wet scrubber is applied in accordance with an embodiment of the present invention. Referring to the drawings, the second combustion gas treatment system may include a combustion chamber 10, a denitration unit 20, a dust collector 30, a wet scrubber 100, and a stack 50.

The combustion gas treatment system of FIG. 4 is distinguished from the embodiment of FIG. 3 in that a combustion chamber 10 capable of in-furnace desulfurization treatment is used. That is, in FIG. 4, the combustion chamber 10 may further include a desulfurizing agent supply unit. In one embodiment, limestone or limestone slurry may be injected into the combustion chamber 10 together with the fuel as a desulfurizing agent.

The denitration apparatus 20, the dust collecting apparatus 30, the wet scrubber 100, and the stack 50 in FIG. 4 have the same or similar functions and functions as those in FIG. 3, do.

4, the denitration unit 20, the dust collecting unit 30, the wet scrubber 100, and the stack 50 are sequentially arranged at the rear end of the combustion chamber 10. However, And the order of the processing apparatus may be changed or various other various processing units may be added according to a specific embodiment.

Now, the wet cleaning apparatus 100 according to an embodiment of the present invention will be described in detail with reference to FIGS. 5 to 7. FIG.

5 is a block diagram of a flue gas wet scrubber 100 according to one embodiment. Referring to the drawings, a wet scrubber 100 according to an embodiment may include a high temperature cleaning section 110, a temperature control section 120, and a low temperature cleaning section 130.

In one embodiment, the hot cleaning section 110 is configured to cool / heat the supplied combustion gas to a first temperature range and remove sulfur trioxide (SO ₃ ) and ammonia (NH ₃ ) from the combustion gas within this temperature range can do. In one embodiment, the first temperature range may be, for example, 90 degrees to less than 100 degrees. As shown in the following reaction formula, sulfur trioxide reacts with water to form sulfuric acid (H ₂ SO ₄ ) by wet cleaning, and ammonia reacts with sulfuric acid to produce ammonium sulfate ((NH ₄ ) ₂ SO ₄ ). Ammonium sulfate can be precipitated and removed in the form of a salt.

SO ₃ + H ₂ O - > H ₂ SO ₄

NH ₃ + H ₂ SO ₄ → (NH ₄ ) ₂ SO ₄

In addition, sodium hydroxide may be added as a neutralizing agent, and sodium sulfate may be formed in a salt form and removed as shown in the following reaction formula.

_{2NaOH + H 2 SO 4 → Na} 2 SO 4 + 2H 2 O

In addition, when hydrogen chloride (HCl) is contained in the combustion gas, ammonium chloride (NH ₄ Cl) can be formed in the form of a salt and can be removed by reacting hydrogen chloride with ammonia as shown in the following reaction formula, and sodium hydrogencarbonate or sodium hydroxide is neutralized When added, sodium chloride (salt) may be produced.

HCl + NH ₃ → NH ₄ Cl

HCl + NaHCO ₃ → NaCl + CO ₂ + H ₂ O

HCl + NaOH → NaCl + H ₂ O

On the other hand, most of the sulfur dioxide (SO ₂₎ within the time hot preferable that the cleaning section 110, temperature is for example held between ° C 90 ° to 100 inside of, and combustion gas in the atmosphere of such a high-temperature cleaning section 110 is water And passes through the high temperature cleaning section 110 without being dissolved in the high temperature cleaning section 110.

Therefore, the high temperature cleaning section 110 removes sulfur trioxide (SO ₃ ), ammonia (NH ₃ ), hydrogen chloride (HCl), and fine dust from the combustion gas and discharges the combustion gas. ).

The temperature regulating unit 120 regulates a predetermined temperature lower than the first temperature range of the combustion gas, that is, a second temperature range, and in one embodiment, the second temperature range may be, for example, 40 to 60 degrees. The temperature regulating unit 120 may be realized by a known heat exchanger or a cooling device.

The combustion gas cooled to the second temperature range in the temperature regulating unit 120 is supplied to the low temperature cleaning unit 130. The low temperature cleaning section 130 can remove sulfur dioxide (SO ₂ ) from the combustion gas by wet scrubbing. That is, sulfurous acid (H ₂ SO ₃ ) is produced by reacting sulfur dioxide with water by wet washing as shown in the following reaction formula, and when sodium hydroxide is added as a neutralizing agent, sulfurous acid reacts with a neutralizing agent to form sodium sulfite (Na ₂ SO ₃ ) Or sodium sulphate (Na ₂ SO ₄ ) are produced and they can be precipitated and removed in the form of a salt.

SO ₂ + H ₂ O - > H ₂ SO ₃

H ₂ SO ₃ + ₂ NaOH → Na ₂ SO ₃ + 2H ₂ O

Na ₂ SO ₃ + ½O ₂ → Na ₂ SO ₄

As described above, according to the wet scrubber 100 according to the embodiment of the present invention, sulfur oxide (SOx) can be separated and removed by strongly acidic sulfur trioxide (SO ₃ ) and slightly acidic sulfur dioxide (SO ₂ ) There is an advantage that water treatment is easy. In addition, since ammonia is removed by the removal of sulfur trioxide, the excess ammonia discharged from the denitration unit 20 at the front end, which is not used for nitrogen oxide removal, can be removed from the wet scrubber 100, .

Referring now to FIG. 6, a specific exemplary configuration of the combustion gas wet scrubber 100 according to one embodiment will be described. Referring to the drawings, a wet scrubber 100 according to an embodiment includes a high temperature cleaning section 110, a temperature control section 120, and a low temperature cleaning section 130.

The high temperature cleaning section 110 may include a chamber 111 and a heat exchanger 114 disposed inside the chamber 111, a cleaning water injection nozzle 115 and a channel section 116.

The chamber 111 has a closed inner space and may have an inlet 112 for injecting the combustion gas into the chamber and an outlet 113 for discharging the combustion gas to the outside of the chamber. The heat exchanger 114 may be disposed above the rinse water injection nozzle 115 and serves to lower the temperature of the combustion gas injected into the chamber 111 through the injection port 112 to the first temperature range. In one embodiment, the first temperature range may be from 90 degrees centigrade to 100 degrees centigrade, more preferably from about 3.degree. Centered at 95 degrees.

When the temperature of the combustion gas is lower than the first temperature range, the heat exchanger 114 may heat the combustion gas, or alternatively, a separate heating means (not shown) may be provided for heating the combustion gas . A temperature sensor (not shown) for measuring the temperature of the combustion gas injected into the injection port 112 can be provided at the front end or the rear end of the injection port 112. With this configuration, The combustion gas can be cooled or heated using the heater 114 or the heating means.

The rinsing water injection nozzle 115 is disposed in the chamber 111 downstream of the heat exchanger 114. The term 'upstream' or 'front end' of any component herein refers to the upper side of the component relative to the flow direction of the combustion gas and the term 'downstream' or 'downstream' refers to the lower side of the component.

In the illustrated embodiment, a cleaning water injection nozzle 115 is disposed below the heat exchanger 114, and a channel portion 116 is disposed below the cleaning water injection nozzle 115. At a lower portion of the channel portion 116, that is, at a lower end portion of the chamber 111, a reservoir 117 for maintaining a predetermined amount of washing water is provided. For example, water (H 2 O) can be used as the washing water, and a neutralizing agent such as sodium hydroxide or sodium bicarbonate, an additive, etc. can be injected together if necessary.

The cleaning water injection nozzle 115 is connected to the reservoir 117 by a pipe L1 and operates the pump P1 to supply rinse water of the reservoir 117 to the injection nozzle 115, The washing water can be sprayed into the chamber through the shower head.

The channel portion 116 is a structure having a plurality of vertically arranged through-holes. Figs. 7 (a) and 7 (b) show an exemplary configuration of the channel portion 116, respectively. 7 (a) is a channel portion of a honeycomb structure, and has a structure in which a plurality of tubular channels 1161 having a hexagonal cross section are formed in the vertical direction. 7 (b) has a structure in which a plurality of tubular channels 1163 having a circular cross-section are formed in the vertical direction. In alternative embodiments, the cross-sectional shape of each of the channels 1161 and 1163 may have any shape, e.g., a circle, an ellipse, or a polygon.

The diameter and the vertical length of each of the channels 1161 and 1163 may vary depending on the specific embodiment. In one embodiment, the diameter of the channels 1161, 1163 may be 1 cm, for example, and the length in the up and down direction may be 50 cm. The cleansing water sprayed from the spray nozzle 115 falls on the channel portion 116 to form a water film on the inner surfaces of the channels 1161 and 1163.

The combustion gas having the temperature in the first temperature range passes through the narrow channel formed with the water film as it passes through the channel part 116 and the sulfur trioxide (SO ₃ ) and ammonia (NH ₃ ) It is adsorbed on the surface while being in contact with the surface or the water film, or dissolved in the washing water. For example, sulfur trioxide (SO ₃ ) can be adsorbed on the surfaces of the channels 1161 and 1163 and dissolved in the washing water, and ammonia (NH ₃ ) can be dissolved in contact with the water film of the washing water. In addition, the fine particles contained in the combustion gas can be dissolved in most of the washing water in contact with the washing water when passing through the channel portion 116. However, most of the sulfur dioxide (SO ₂ ) does not dissolve and passes through the channel portion 116 because the solubility in water is not high in the first temperature range. The combustion gas passing through the channel portion 116 can be supplied to the temperature regulating portion 120 through the exhaust port 113. [

The cleansing water in which sulfur trioxide and ammonia are dissolved falls into the reservoir 117. In the storage tank, sulfur trioxide reacts with the washing water to generate sulfuric acid (H ₂ SO ₄ ), and ammonia reacts with sulfuric acid to form ammonium sulfate ((NH ₄ ) ₂ SO ₄ ). The ammonium sulfate can be precipitated in the form of a salt in the bottom of the storage tank 117 and discharged to the outside through a sediment outlet 118 installed on the floor for example.

In one embodiment, the hot cleaning section 110 may further include a heater 119 for heating the wash water to a first temperature range when the temperature of the wash water stored in the reservoir 117 is low. Although not shown in the drawing, it will be understood that the present invention may further include a supply pipe for supplying wash water to the storage tank 117 when the wash water is insufficient, and a processing means for discharging and processing the wash water.

The temperature regulating unit 120 may include a chamber 121 and a water injection nozzle 124 and a heat exchanger 125 disposed inside the chamber 121.

The chamber 121 has a closed inner space and may have an inlet 122 for injecting combustion gas into the chamber and an outlet 123 for discharging the combustion gas to the outside of the chamber. The heat exchanger 125 is for cooling the combustion gas to a temperature within the second temperature range, and a known heat exchange system can be used. In one embodiment, the heat exchanger 125 is comprised of a pipe filled with refrigerant, and the combustion gas can be cooled to a second temperature range by heat exchange with the refrigerant while contacting the surface of the pipe. The refrigerant may be any gas (e.g., air) or liquid (e.g., water).

At this time, in order to increase heat exchange efficiency, water can be formed on the surface of the pipe to form a water film. For this purpose, the water injection nozzle 124 can be disposed above the heat exchanger 125. At a lower portion of the heat exchanger 125, a reservoir 126 for storing the sprayed water is disposed. The water injection nozzle 124 is connected to the reservoir 126 by a pipe L2 and operates the pump P2 to supply the water in the reservoir 126 to the injection nozzle 124 and through the injection nozzle 124 Can be injected toward the pipe of the heat exchanger (125). Water injected into the piping can increase the heat transfer coefficient between the combustion gas and the refrigerant in the piping, thereby improving the heat exchange efficiency.

The solubility of sulfur dioxide in cleansing water (such as water) increases with decreasing temperature, but more energy is required to lower the temperature of the combustion gas. Therefore, the second temperature range can be set in consideration of the solubility of sulfur dioxide and the energy required for cooling the combustion gas. In one embodiment, the second temperature range may be from 40 degrees Celsius to 60 degrees Celsius, and more preferably from 50 degrees Celsius to 55 degrees Celsius.

The low temperature cleaning section 130 may include a cleaning water injection nozzle 134 and a channel section 135 disposed inside the chamber 131 and the chamber 131.

The chamber 131 has a closed inner space and may have an inlet 132 for injecting combustion gas into the chamber and an outlet 133 for discharging the combustion gas to the outside of the chamber.

In the illustrated embodiment, the channel portion 135 is disposed below the cleaning water injection nozzle 134. In the lower portion of the channel portion 135, a reservoir 136 for maintaining the washing water for a predetermined level is provided. As the washing water channel, the same washing water as that used in the high temperature washing section 110 may be used.

The cleaning water injection nozzle 134 is connected to the reservoir 136 by a pipe L3 and operates the pump P3 to supply the rinse water of the reservoir 136 to the injection nozzle 134, The washing water can be sprayed into the chamber through the shower head.

The channel portion 135 is a structure having a plurality of vertically arranged through holes and has the same or similar structure and function as the channel portion 116 of the high temperature cleaning portion 110. Therefore, for example, the channel portion shown in Fig. 7 (a) or 7 (b) can be used, and a detailed description thereof will be omitted.

The combustion gas having the temperature in the second temperature range passes through the narrow channel in which the water film of the washing water is formed as it passes through the channel portion 135. When sulfur dioxide (SO ₂ ) of the combustion gas contacts with the water film of the channel, Soluble in water. In addition, the fine particles contained in the combustion gas are also dissolved in contact with the washing water while passing through the channel part 135.

The cleansing water in which the sulfur dioxide has dissolved falls into the storage tank 136, reacts with water in the storage tank to become sulfurous acid, and the sulfurous acid reacts with, for example, sodium hydroxide, which is a neutralizing agent, to form sodium sulfite. Sodium sulfite can be deposited on the bottom of the reservoir 136 and then discharged to the outside for treatment.

Although the embodiments have been described with reference to the drawings, various modifications may be made in addition to the above-described embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the scope of the appended claims, as well as the appended claims.

10: combustion chamber 20: denitration device
25: Acid gas cleaning facility 30: Dust collector
50: stack 100: wet cleaning device
110: high temperature cleaning section 120: temperature control section
130:

Claims (14)

1. A wet scrubber (100) for cleaning a combustion gas,
A high temperature cleaning section 110 for removing wet sulfur oxide (SO ₃ ) and ammonia (NH ₃ ) from a combustion gas in a first temperature range of 100 ° C or less;
A temperature regulator 120 for cooling the gas discharged from the high temperature cleaning unit to a second temperature range lower than the first temperature range; And
And a low temperature cleaning section (130) for removing sulfur dioxide (SO ₂ ) from the gas discharged from the temperature regulating section (120) by wet cleaning. The method according to claim 1,
Wherein the first temperature range is from 90 degrees to 100 degrees Celsius and the second temperature range is from 40 degrees Celsius to 60 degrees Celsius. The apparatus of claim 1, wherein the high temperature cleaning section (110)
A first chamber (111) having a closed interior space;
A first cleaning water injection nozzle (115) for spraying cleaning water into the first chamber; And
And a first channel part (116) disposed at a lower end of the first cleaning water injection nozzle and having a plurality of tubular channels each having a circular, elliptical, or polygonal cross section in the vertical direction,
And sulfur dioxide and ammonia in the combustion gas are dissolved and removed in the washing water flowing along the surface of the first channel portion when the combustion gas passes through the first channel portion. 4. The apparatus of claim 3, wherein the high temperature cleaning section (110)
A heat exchanger (114) disposed at a front end of the first washing water injection nozzle (115) for cooling the combustion gas at a temperature higher than the first temperature range to the first temperature range; or,
A heater for heating the combustion gas at a temperature lower than the first temperature range to the first temperature range, the heating unit being disposed at a front end of the first cleaning water injection nozzle; ≪ / RTI > further comprising at least one of the following: < RTI ID = 0.0 > The apparatus of claim 1, wherein the temperature regulator (120)
A second chamber (121) having a closed inner space; And
And a pipe disposed in the second chamber and through which refrigerant flows,
Wherein the gas introduced into the second chamber exchanges heat with the refrigerant while passing between the pipes, and is cooled to the second temperature range. 6. The method of claim 5,
Wherein the temperature regulating unit (120) further comprises: a water spray nozzle (124) disposed at an upper portion of the pipe and spraying water into the second chamber. 4. The apparatus of claim 3, wherein the low temperature cleaning section (130)
A third chamber 131 having a closed inner space;
A second cleaning water injection nozzle 134 for spraying cleaning water into the third chamber; And
And a second channel part (135) disposed at a lower end of the second cleaning water injection nozzle and having a plurality of tubular channels each having a circular, elliptical, or polygonal cross section in the vertical direction,
And sulfur dioxide in the gas is dissolved and removed in the washing water flowing along the surface of the second channel part when the gas flowing into the third chamber passes through the second channel part. A wet cleaning method for cleaning a combustion gas,
A high temperature cleaning step of removing sulfur trioxide (SO ₃ ) and ammonia (NH ₃ ) from the combustion gas in the first temperature range of not more than 100 degrees centigrade by wet scrubbing in the first chamber;
Cooling the gas discharged from the first chamber to a second temperature range lower than the first temperature range in the second chamber; And
In a third chamber, a low temperature cleaning step of removing sulfur dioxide (SO ₂ ) from the gas discharged from the second chamber by wet cleaning. 9. The method of claim 8,
Wherein the first temperature range is from 90 degrees to 100 degrees Celsius and the second temperature range is from 40 degrees Celsius to 60 degrees Celsius. 9. The apparatus of claim 8,
A first cleaning water injection nozzle (115) for spraying cleaning water into the first chamber; And
And a first channel part (116) disposed at a lower end of the first cleaning water injection nozzle and having a plurality of tubular channels each having a circular, elliptical, or polygonal cross section in the vertical direction,
Wherein the high temperature cleaning step comprises passing a combustion gas through the first channel portion to dissolve sulfur trioxide and ammonia in the combustion gas in rinse water flowing along the surface of the first channel portion. Way. 11. The apparatus of claim 10, wherein the first chamber
A heat exchanger (114) disposed at a front end of the first washing water injection nozzle (115) for cooling the combustion gas at a temperature higher than the first temperature range to the first temperature range; or,
A heater for heating the combustion gas at a temperature lower than the first temperature range to the first temperature range, the heating unit being disposed at a front end of the first cleaning water injection nozzle; ≪ / RTI > further comprising at least one of the following. 9. The method of claim 8,
Wherein the second chamber comprises a pipe disposed in the second chamber and through which the refrigerant flows,
Wherein the temperature control step comprises passing the gas flowing into the second chamber between the pipes to cool the gas to the second temperature range by heat exchange between the gas and the refrigerant, Way. 13. The method of claim 12,
Wherein the second chamber further comprises a water spray nozzle (124) disposed at an upper portion of the pipe to spray water into the second chamber. 11. The apparatus of claim 10, wherein the third chamber comprises:
A second cleaning water injection nozzle 134 for spraying cleaning water into the third chamber; And
And a second channel part (135) disposed at a lower end of the second cleaning water injection nozzle and having a plurality of tubular channels each having a circular, elliptical, or polygonal cross section in the vertical direction,
Wherein the low temperature cleaning step comprises passing the gas introduced into the third chamber to the second channel portion and dissolving the sulfur dioxide in the gas into the washing water flowing along the surface of the second channel portion, Gas wet cleaning method.

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