KR20190136316A - A system for reducing nitrogen oxide - Google Patents

Abstract

A nitrogen oxide removal facility is provided. In one embodiment, a nitrogen oxide removal equipment for removing the nitrogen oxides in the exhaust gas generated by combustion to discharge to the stack, comprising: a combustion furnace in which a combustion process is performed; A first reducing agent supply unit supplying a first reducing agent to the combustion furnace and a second reducing agent supplying unit supplying a second reducing agent; A heat exchanger through which exhaust gas flows from the combustion furnace; A temperature detector for detecting a temperature in the combustion furnace; A gas concentration detector for detecting a component and a concentration of the exhaust gas discharged from the stack; A first flow control valve for controlling the discharge of the first reducing agent and a second flow control valve for controlling the discharge of the second reducing agent; And a control unit which receives detection information from various detection units, compares the detection information with preset information, and controls the first flow regulating valve and the second flow regulating valve. As a result of the exothermic reaction, the temperature in the combustion furnace can be controlled.

Description

Nitrogen oxide removal equipment {A SYSTEM FOR REDUCING NITROGEN OXIDE}

The present invention relates to a nitrogen oxide removal equipment, and more particularly to a nitrogen oxide removal equipment that can control the temperature in the furnace using a reducing agent.

In general, nitrogen oxide (NOx) contained in the exhaust gas refers to nitrogen monoxide, nitrogen dioxide, nitrous oxide, and the like, and is one of the representative substances causing environmental pollution, such as other carbon oxides and sulfur oxides.

In recent years, as environmental standards have been strengthened, many power plants using natural gas, known as clean fuel, have been constructed. Pollution from sulfur oxides has reduced severity, while NOx, which is caused by the oxidation of nitrogen in the air at high temperatures, is still a problem. It is becoming.

In this regard, as disclosed in Korean Patent No. 1199267 and the like, Selective Caltalytic Reduction (SCR), Selective Non Catalytic Reduction (SNCR), and the like are known and used for NOx treatment.

However, when treating NOx through these methods, the NO ₂ component of NOx (NO, NO ₂ ) generated in large quantities according to incomplete combustion and temperature conditions during initial combustion causes yellow smoke, which causes yellow smoke. Emitted as a large amount of harmful substances, with the appearance of visual discomfort.

On the other hand, the SCR method has a disadvantage in that the initial investment cost and the installation period is long according to the use of the catalyst, despite the advantages of high nitrogen oxide removal efficiency, and accordingly there have been many studies on the SNCR method.

However, when using the conventional SNCR method, it is difficult to overcome the problem that the efficiency is lower than that of the general SCR, and the problem is that the process is performed at a considerably higher temperature than the SCR method, and therefore, an expensive auxiliary fuel for maintaining a high temperature must be used. .

The problem to be solved by the present invention, it is possible to maintain a high temperature without using expensive auxiliary fuel, improve the efficiency of nitrogen oxide removal by using the primary and secondary reducing agent, landfill gas (LFG, Land Fill) as the primary reducing agent It is to provide eco-friendly and economical nitrogen oxide removal equipment using gas or natural gas.

In order to solve the above problems, the present invention provides a nitrogen oxide removal facility for removing nitrogen oxides in exhaust gas generated by combustion and discharging them into stacks, comprising: a combustion furnace in which a combustion process is performed; A first reducing agent supply unit supplying a first reducing agent to the combustion furnace and a second reducing agent supplying unit supplying a second reducing agent; A heat exchanger through which exhaust gas flows from the combustion furnace; A temperature detector for detecting a temperature in the combustion furnace; A gas concentration detector for detecting a component and a concentration of the exhaust gas discharged from the stack; A first flow control valve for controlling the discharge of the first reducing agent and a second flow control valve for controlling the discharge of the second reducing agent; And a control unit which receives detection information from various detection units, compares the detection information with preset information, and controls the first flow regulating valve and the second flow regulating valve. An exothermic reaction provides a nitrogen oxide removal plant in which the temperature in the furnace is controlled.

That is, the nitrogen oxide removal equipment may use the first reducing agent and the second reducing agent, and may maintain the temperature in the combustion furnace at a high temperature by using heat generated during the combustion of the first reducing agent with the nitrogen oxide in the combustion furnace. .

In this case, the first reducing agent may include at least one of landfill gas (LFG) and natural gas, and the second reducing agent may include urea water.

That is, the nitrogen oxide removal equipment uses at least one of landfill gas and natural gas as a raw material of the first reducing agent, thereby providing an eco-friendly and economical nitrogen oxide removal equipment by recycling industrial waste.

For example, the first reducing agent may include methane gas.

That is, the nitrogen oxide removal equipment can control the internal temperature of the combustion furnace including methane gas as the first reducing agent and perform the nitrogen oxide removal process, and simultaneously reduce nitrogen oxide and sulfur lead by removing nitrogen monoxide and nitrogen dioxide together. Can be.

On the other hand, the control unit may control the discharge amount of the first reducing agent discharged from the first reducing agent supply to the combustion furnace so that the temperature detected from the temperature detector is 850 ℃ to 1100 ℃.

That is, as the nitrogen oxide removal equipment measures the temperature inside the furnace through the control unit, when the temperature inside the furnace is less than 850 ° C., the first flow regulating valve may be controlled to further discharge the first reducing agent. When the temperature is greater than 1100 ° C., the first flow control valve may be controlled to reduce the supply amount of the first reducing agent or to block the supply. For example, the controller may control the first flow control valve so that the internal temperature of the furnace is 900 ° C to 1000 ° C.

The control unit may compare the nitrogen oxide concentration detected by the gas concentration detection unit with the preset information, so that the second reducing agent is discharged from the second reducing agent supply unit to the combustion furnace when it is equal to or greater than the preset information. .

That is, when the nitrogen oxide removal equipment is measured that the concentration of nitrogen oxides discharged through the stack is higher than the preset information range, the second flow control valve may be controlled by the control unit so that the second reducing agent may be further discharged. When it is determined that the lower information range is set, the second flow control valve may be controlled to reduce the supply amount of the second reducing agent or to block the supply.

The control unit may compare the carbon monoxide concentration detected by the gas concentration detection unit with the preset information when the first reducing agent is supplied from the first reducing agent supply unit to the combustion furnace, and the heat exchanger may be performed when the predetermined information is equal to or greater than the preset information. It is possible to increase the amount of air supplied to the air.

In other words, the nitrogen oxide removal equipment can suppress the emission of pollutants by preventing incomplete combustion of the first reducing agent and nitrogen oxide.

As another example, the method may further include a preheating unit for preventing condensation of the second reducing agent discharged from the second reducing agent supply unit to the combustion furnace and increasing a vaporization rate.

That is, the nitrogen oxide removal equipment may prevent damage to the second reducing agent supply unit piping and the nozzle by preheating the second reducing agent supply unit to the preheating unit so that the decomposition temperature of the urea water is within a predetermined temperature range.

In this case, the preheater may control the decomposition temperature of the second reducing agent discharged from the second reducing agent supply unit to the combustion furnace to be 350 ° C. or more.

That is, the nitrogen oxide removal equipment is lowered the decomposition temperature of the second reducing agent to prevent damage to the urea water pipes and nozzles caused by the generation of ammeline (melline) or melamine (melamine), the injection nozzle suddenly suddenly supplied when the second reducing agent Preventing cooling and increasing nozzle replacement and maintenance intervals can reduce maintenance and maintenance costs.

The controller may control the first reducing agent to be supplied to the combustion furnace and then the second reducing agent to be supplied.

In other words, the nitrogen oxide removal equipment removes nitrogen oxides by first supplying a first reducing agent which is relatively inexpensive to a combustion furnace and uses landfill gas as a raw material, and removes nitrogen oxides not removed by the first reducing agent with a second reducing agent. By doing so, it is possible to increase the nitrogen oxide removal efficiency in an economical and environmentally friendly way.

In addition, the controller may control to supply 2 to 3 equivalents of the second reducing agent to 1 equivalent of nitrogen oxide during the initial operation of the nitrogen oxide removal equipment.

In this case, the controller may control the second reducing agent to be discharged from the second reducing agent supply unit to the combustion furnace during the initial operation of the nitrogen oxide removal equipment, and may block the supply of the first reducing agent to the combustion furnace. .

That is, the nitrogen oxide removal equipment can variably use two kinds of reducing agents, and for example, it is possible to control the supply amount of the first reducing agent and the second reducing agent by detecting the amount of nitrogen oxide discharged from the stack in real time.

In addition, an embodiment of the present invention, in the nitrogen oxide removal equipment automatic control system using the nitrogen oxide removal equipment described above, by comparing the temperature information detected from the temperature detector with a predetermined information, and determines the internal temperature of the combustion furnace It is provided a nitrogen oxide removal facility automatic control system, the automatic control so that is maintained within a predetermined temperature information range.

At this time, the combustion furnace, the first combustion chamber is supplied with a first reducing agent; An ignition burner provided in the first combustion chamber; A second combustion chamber supplied with a second reducing agent; And an auxiliary burner provided in the second combustion chamber, wherein the controller may control at least one of the ignition burner, the auxiliary burner, and the first reducing agent supply unit to automatically control the internal temperature of the combustion furnace.

For example, the control unit compares the component information and concentration information of the exhaust gas detected by the gas concentration detection unit with a predetermined information, and the supply amount of the first reducing agent supplied to the combustion furnace from the first reducing agent supply unit and the The second reducing agent supply unit may control at least one of the supply amount of the second reducing agent supplied to the combustion furnace.

That is, the automatic control system for the nitrogen oxide removal equipment may control the supply amount of the first reducing agent and the second reducing agent by monitoring the internal temperature of the combustion furnace, and may determine whether the ignition burner and the auxiliary burner are operated and automatically control.

According to an embodiment of the present invention, by maintaining the internal temperature of the furnace at a temperature suitable for the second reducing agent to react by using a first reducing agent that performs an exothermic reaction with the nitrogen oxide, while reducing the cost to be added to the reducing agent The removal efficiency can be improved.

In addition, according to an embodiment of the present invention, the temperature detection unit detects the internal temperature information of the combustion furnace, the control unit automatically controls the supply amount of the first reducing agent and the second reducing agent, and maintains the internal temperature of the combustion furnace within an appropriate reaction temperature range. By controlling so as to reduce the cost to be added to the reducing agent by utilizing the first reducing agent, which is relatively low in cost compared to the second reducing agent, it is possible to improve the nitrogen oxide removal efficiency.

1 to 2 show a nitrogen oxide removal equipment according to an embodiment of the present invention.
3 shows a combustion furnace, a temperature detector and a preheater according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms, and only the embodiments are provided to make the disclosure of the present invention complete and to those skilled in the art. It is provided to give more complete information.

Where an element is referred to herein as being located above another element 'above' or 'below', this means that the element is located directly above another element 'above' or 'below' or between additional elements Includes all meanings that may be intervened. In the present specification, the term 'upper' or 'lower' is a relative concept set at an observer's viewpoint, and when the observer's viewpoint is different, 'upper' may mean 'lower', and 'lower' may mean 'upper' It may mean.

Like reference numerals in the drawings indicate substantially the same elements as each other. Also, the terms 'comprise' or 'have' are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described, or one or more other features, numbers, steps It is to be understood that the present invention does not exclude, in advance, the possibility of the presence or the addition of an operation, a component, a part, or a combination thereof.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

1 to 2 show a nitrogen oxide removal equipment according to an embodiment of the present invention.

Referring to FIG. 1, the nitrogen oxide removal facility according to the present invention includes a first reducing agent and a first agent to remove nitrogen oxides in a process of discharging exhaust gas discharged by combustion from the combustion furnace 100 to the stack 400. 2 The reducing agent is supplied and the supply amount is controlled by the controller. At this time, the nitrogen oxide removal equipment is SNCR method is applied, the catalyst may not be necessary.

In the combustion furnace 100 in which the combustion process is performed, exhaust gas is generated, and the first reducing agent and the second reducing agent may be supplied to the combustion furnace 100 from the first reducing agent supply unit 130 and the second reducing agent supply unit 140. have.

The first reducing agent may include at least one of a landfill gas and a natural gas, thereby recycling the industrial waste and performing an environmentally friendly process. For example, the first reducing agent may include methane gas.

The second reducing agent includes urea water, and may be supplied to the combustion furnace 100 at the same time as the first reducing agent or after the first reducing agent is supplied.

At this time, the second reducing agent, for example, urea water has a slow reaction rate at a temperature of less than 850 ℃, can be converted to nitrogen monoxide at a temperature of more than 1100 ℃. Therefore, it is necessary to control the temperature inside the combustion furnace 100 when the second reducing agent is supplied to the combustion furnace 100.

Therefore, the inventors of the present invention have devised a method that can significantly remove the nitrogen oxide removal efficiency by using a first reducing agent which is capable of removing nitrogen oxide but lower in cost than the second reducing agent.

That is, the nitrogen oxide removal reaction by the first reducing agent, for example, methane gas is an exothermic reaction and the specific reaction formula is as follows.

In addition, the combustion reaction of the first reducing agent is as follows.

That is, the first reducing agent may serve as an auxiliary fuel for removing nitrogen oxides and maintaining the internal temperature of the combustion furnace 100 at a high temperature, wherein the internal temperature of the combustion furnace 100 is 850 ° C to 1100 ° C, for example. For example, it may be controlled to be 900 ℃ to 1000 ℃.

In this case, the supply amount of the first reducing agent may be controlled through the control unit 500 to be described later.

On the other hand, the methane ignition point is approximately 800 ℃ based on the 8% concentration, carbon monoxide may be generated as shown below (Equation 4) when supplied at a temperature below the ignition point or incomplete combustion due to lack of oxygen.

Therefore, the controller 500 to be described later controls so that the internal temperature of the combustion furnace 100 is 800 ° C. or more when the first reducing agent is supplied, and the concentration of carbon monoxide discharged from the stack 400 exceeds the air pollution emission standard. If detected, the supply amount of air supplied to the heat exchanger 200 to be described later can be increased.

In addition, a reaction formula for removing nitrogen oxides using a second reducing agent, for example, urea water, is as follows.

Equation (5) shows the reaction to the process of decomposition of ammonia when urea water is supplied into the combustion furnace 100 in the aqueous solution state. When urea water is supplied into the combustion furnace 100 in an aqueous state, ammonia is smoothly generated from urea water at a temperature of 350 ° C. or higher, so that the air for injection of the urea water supply nozzle (second nozzle 142 of FIG. 3) will be described later. The heat exchanger 200 may be used to preheat. Alternatively, the second nozzle (FIGS. 3 and 142) may be integrally provided with the auxiliary burner 112 of the second combustion chamber 120.

Equations 6 and 8 show reactions in which ammonia decomposed in urea water reduces nitrogen oxides to nitrogen. At this time, the production of ammonia by the formula (5) and the reaction of (formula 6) occur continuously and are represented by (Formula 7), and the continuous reaction of (Formula 5) and (Formula 8) is represented by (Formula 9). do.

At this time, the supply amount of the initial urea is calculated by the nitrogen molar ratio (NH ₃ / NOx) is supplied to 2 to 3 times to gradually reduce and supply to the target concentration of nitrogen oxide discharged to the stack (400).

In addition, when the internal temperature of the combustion furnace 100 exceeds 1,100 ° C, since nitrogen monoxide may be generated by urea water as shown in Equation 10 below, the temperature of the region in which urea water, which is a secondary reducing agent, is supplied does not exceed 1,100 ° C. To prevent it.

In this case, the supply amount of the second reducing agent and the internal temperature of the combustion furnace 100 may be controlled through the controller 500 to be described later.

The heat exchanger 200 is where the exhaust gas discharged from the combustion furnace 100 is introduced, for example, the heat exchanger 200 may be a shell & tube method. In addition, it preheats the air supplied to the combustion furnace 100, and performs the function of preheating the air for urea water injection. For example, the air from which the second reducing agent is injected may be preheated in the second nozzle 142 described later with reference to FIG. 3. That is, the heat exchanger 200 may improve the nitrogen oxide removal reaction efficiency in the combustion furnace 100 by maintaining or improving the vaporization rate of urea water.

Meanwhile, the air preheated through the heat exchanger 200 is supplied to the second reducing agent supply unit 140, so that the urea water supply nozzle in the process of decomposing urea water into ammonia as described above (Equation 5). The temperature of the used air can be made to be 350 ℃ or more.

The air pollution prevention facility 300 is a place where the exhaust gas passing through the heat exchanger 200 is introduced, and it is possible to remove particulate contaminants and gaseous contaminants, and a well-known configuration may be applied. A reaction tower and a bag filter may be installed.

The exhaust gas passing through the air pollution prevention facility 300 is discharged to the stack 400, and a gas concentration detection unit 410 may be installed to detect a component and a concentration of the exhaust gas discharged from the stack 400.

The gas concentration detector 410 may detect a composition of exhaust gas such as carbon monoxide, carbon dioxide, oxygen, and nitrogen oxides.

The control unit 500 may receive detection information from various detection units, compare the detection information with preset information, and control the first flow control valve 131 and the second flow control valve 141.

In this case, the various detection units may include a gas concentration detection unit 410 for detecting the exhaust gas composition discharged from the stack 400 and a temperature detection unit 150 for detecting internal temperature information of the combustion furnace 100.

For example, the control unit 500 may control the discharge amount of the first reducing agent discharged from the first reducing agent supply unit 130 to the combustion furnace 100 so that the temperature detected from the temperature detecting unit 150 is 850 ° C to 1100 ° C. have.

That is, as shown in the above formulas (1) to (3), the first reducing agent may generate an exothermic reaction in the nitrogen oxide removal reaction, and may act as an auxiliary fuel by the combustion reaction of the first reducing agent itself. The first flow control valve 131 may be controlled by the controller 500 such that the temperature detected from the 150 is 850 ° C to 1100 ° C.

For example, the controller 500 may control the first reducing agent to be supplied to the combustion furnace 100 and then the second reducing agent to be supplied.

That is, the nitrogen oxide removal equipment first supplies the first reducing agent to the combustion furnace 100 to raise and maintain the internal temperature of the combustion furnace 100 to the combustion temperature of the second reducing agent, for example, 850 ° C to 1100 ° C, By supplying 2 reducing agents to the combustion furnace 100, the nitrogen oxide removal reaction efficiency by a 2nd reducing agent can be improved significantly.

In addition, the nitrogen oxide removal equipment is relatively inexpensive to the combustion furnace 100, and supplies a first reducing agent, which is a landfill gas or the like as a raw material, to remove nitrogen oxides, and to remove nitrogen oxides not removed by the first reducing agent. By removing with a reducing agent, it is possible to increase the efficiency of nitrogen oxide removal in an economical and environmentally friendly way.

For example, the control unit 500 compares the nitrogen oxide concentration detected by the gas concentration detection unit 410 with preset information, and when the information is higher than the preset information, the second reducing agent from the second reducing agent supply unit 140 to the combustion furnace 100. Can be discharged.

That is, when the composition of the gas detected by the gas concentration detection unit 410, for example, the concentration of the nitrogen oxide detected from the concentrations of carbon monoxide, carbon dioxide, oxygen, and nitrogen oxide is measured to be higher than the preset information range, the controller 500 The second flow regulating valve 141 may be controlled to allow further discharge of the second reducing agent, and when it is determined to be lower than the preset information range, the second flow regulating valve 141 may be controlled to reduce the supply amount of the second reducing agent. I can cut off the supply.

For example, the controller 500 may compare the carbon monoxide concentration detected by the gas concentration detection unit 410 with preset information when the first reducing agent is supplied from the first reducing agent supply unit 130 to the combustion furnace 100. At this time, if the detected carbon monoxide concentration is greater than or equal to the preset information, the control unit 500 increases the supply amount of air supplied to the heat exchanger 200, thereby preventing incomplete combustion of the first reducing agent and nitrogen oxide to suppress the emission of pollutants. Can be.

Meanwhile, referring to FIG. 2, the nitrogen oxide removal facility may further include a preheating unit 160. The preheating unit 160 is to prevent the condensation of the second reducing agent discharged from the second reducing agent supply unit 140 to the combustion furnace 100 and to increase the vaporization rate. The nitrogen oxide removal equipment has a decomposition temperature of urea water in advance. The preheating unit 160 performs a function of preheating the second reducing agent supply unit 140 to have a set temperature range.

For example, the preheater 160 controls the decomposition temperature of the second reducing agent discharged from the second reducing agent supply unit 140 to the combustion furnace 100 to be 350 ° C. or more, so that the pipe of the second reducing agent supply unit 140 Damage to the nozzle can be prevented.

In other words, the nitrogen oxide removal equipment is lowered the decomposition temperature of the second reducing agent to prevent damage to the urea water pipes and nozzles caused by the generation of ammeline (melline) or melamine (melamine), when supplying the second reducing agent using preheating air This prevents the jet nozzle from cooling rapidly and increases the interval between nozzle replacement and inspection.

At this time, the preheating unit 160 may be a separate preheating unit 160 is installed, may refer to the preheating air flows from the heat exchanger 200, or the second combustion chamber 120 to be described later with reference to FIG. It may be provided as an integral with the auxiliary burner 112 installed on the).

In addition, the control unit 500 may control the supply amount of the second reducing agent discharged to the combustion furnace 100 at the initial stage of the operation of the nitrogen oxide removal equipment, for example, 2 to 3 equivalents of the nitrogen oxide of 1 equivalent 2 reducing agents may be supplied.

During the initial operation of the nitrogen oxide removal facility, since the amount of solid waste accumulated in the combustion furnace 100 is small and the formation of the flame is not stable, it may be difficult to remove the pollutants discharged. Therefore, when the temperature of the combustion furnace 100 is low and the emission concentration of nitrogen oxide is low, rather than supplying the first reducing agent, only the second reducing agent is added until a stable temperature of the combustion region in the combustion furnace 100 is secured. Nitrogen oxide removal efficiency can be improved.

That is, the nitrogen oxide removal equipment can use two kinds of reducing agents variably and, for example, can detect the amount of nitrogen oxide discharged from the stack 400 in real time to control the supply amount of the first reducing agent and the second reducing agent. Can be.

3 illustrates a combustion furnace 100, a temperature detector 150, and a preheater 160 according to an embodiment of the present invention.

Referring to FIG. 3, the combustion furnace 100 includes a first combustion chamber 110 and a second combustion chamber 120. The first reducing agent 120 is supplied to the first combustion chamber 110 through the first nozzle 132, and the second reducing agent 120 is supplied to the second combustion chamber 120 through the second nozzle 142.

The first combustion chamber 110 is a place where the combustion reaction occurs by loading the SRF supplied with the ignition burner 111, and the second combustion chamber 120 is provided with an auxiliary burner 112 and exits the combustion furnace 100. The temperature is maintained and a SNCR configuration is provided. At this time, the auxiliary burner 112 may supply an additional heat source by using diesel, kerosene, LPG, etc. so as to raise the internal temperature of the second combustion chamber 120 instantaneously.

The internal temperature of the first combustion chamber 110 and the second combustion chamber 120 is maintained at 850 ° C. to 1100 ° C., which is an appropriate reaction temperature range of the second reducing agent, and the internal temperature information of the combustion furnace 100 by the temperature detector 150. Is detected. For example, the first reducing agent combusted in the first combustion chamber 110 is introduced into the second combustion chamber 120 in the form of a gas.

The temperature detector 150 includes a first temperature detector 151 and a second temperature detector 152.

The first temperature detector 151 may be installed in the first combustion chamber 110 to detect temperature information of the first combustion chamber 110, and may control, for example, an upper temperature of the first combustion chamber 110. That is, whether or not the first temperature detection unit 151 is maintained at a temperature equal to or greater than the ignition point of the supplied first reducing agent and the temperature of the gas that is burned in the first combustion chamber 110 and flows into the second combustion chamber 120 are second to the second temperature. It can be detected whether it is in the appropriate reaction temperature range of a reducing agent.

At this time, the controller 500 controls the operation of the ignition burner 111 so that the temperature detected by the first temperature detector 151 is 850 ° C to 1100 ° C, and the supply amount of the first reducing agent is controlled by the first flow control valve 131. Can be controlled.

The second temperature detector 152 is installed in the second combustion chamber 120 to detect temperature information of the second combustion chamber 120. For example, the first reducing agent in an unburned gas state in the first combustion chamber 110 is provided. And temperature information for checking whether the second combustion chamber 120 is maintained at an appropriate reaction temperature of the second reducing agent supplied to the second combustion chamber 120.

At this time, the control unit 500 controls the operation of the auxiliary burner 112 so that the temperature detected by the second temperature detector 152 is 850 ° C to 1100 ° C, or adjusts the amount of preheated air introduced thereto, or the amount of supply of methane. Can be adjusted.

Meanwhile, the preheater 160 preheats the second reducing agent injected from the second nozzle 142, and the specific function and the preheating temperature are as described above with reference to FIG. 2. For example, the preheating unit 160 may be a form in which preheating air is discharged from the heat exchanger 200, a separate preheating unit 160 may be installed, or may be integrally installed with the auxiliary burner 112. It is also possible.

One embodiment of the present invention also provides a nitrogen oxide removal facility automatic control system using the above-described nitrogen oxide removal facility.

For example, the nitrogen oxide removal facility automatic control system compares and determines the temperature information detected from the temperature detector 150 with preset information, and automatically controls the internal temperature of the combustion furnace 100 to be maintained within the preset temperature information range. Can be.

For example, the controller 500 may control at least one of the ignition burner 111, the auxiliary burner 112, and the first reducing agent supply unit 130 to automatically control the internal temperature of the combustion furnace 100. The control method of the ignition burner 111, the auxiliary burner 112, and the first reducing agent supply unit 130 by the control unit 500 may apply the above-described bar. At this time, the specific control method of the first reducing agent refers to the control of the supply amount of the first reducing agent.

For example, the control unit 500 compares the component information and concentration information of the exhaust gas detected by the gas concentration detection unit 410 with preset information, and is supplied to the rotor combustion furnace 100 of the first reducing agent supply unit 130. At least one of the supply amount of the first reducing agent and the supply amount of the second reducing agent supplied to the combustion furnace 100 of the second reducing agent supply unit 140 may be controlled. The specific control method related to this may be applied to the foregoing.

As described above, the detailed description of the present invention has been made by the embodiments with reference to the accompanying drawings. However, since the above-described embodiments have only been described by way of example, the present invention is limited to the above embodiments. It should not be understood, the scope of the present invention will be understood by the claims and equivalent concepts described below.

For example, the drawings are schematically shown as main components of each component for better understanding, and the thickness, length, number, and the like of each illustrated component may be different from the actual progress of the drawing. In addition, the material, shape, a dimension, etc. of each component shown by said embodiment are not specifically limited as an example, Various changes are possible in the range which does not deviate substantially from the effect of this invention.

100: combustion furnace
110: first combustion chamber
111: ignition burner
120: second combustion chamber
112: auxiliary burner
130: first reducing agent supply unit
131: first flow control valve
132: first nozzle
140: second reducing agent supply unit
141: second flow control valve
142: second nozzle
150: temperature detector
151: first temperature detection unit
152: second temperature detection unit
160: preheater
200: heat exchanger
300: air pollution prevention equipment
400: stack
410: gas concentration detection unit
500: control unit

Claims (14)

In the nitrogen oxide removal equipment for removing the nitrogen oxides in the exhaust gas generated by combustion to discharge to the stack,
A combustion furnace in which a combustion process is performed;
A first reducing agent supply unit supplying a first reducing agent to the combustion furnace and a second reducing agent supplying unit supplying a second reducing agent;
A heat exchanger through which exhaust gas flows from the combustion furnace;
A temperature detector for detecting a temperature in the combustion furnace;
A gas concentration detector for detecting a component and a concentration of the exhaust gas discharged from the stack;
A first flow control valve for controlling the discharge of the first reducing agent and a second flow control valve for controlling the discharge of the second reducing agent; And
A control unit which receives detection information from various detection units, compares the detection information with preset information, and controls the first flow control valve and the second flow control valve;
Including,
The temperature of the combustion furnace is controlled as a result of the exothermic reaction of the first reducing agent and nitrogen oxide, nitrogen oxide removal equipment.
The method according to claim 1,
The first reducing agent includes at least one of landfill gas (LFG) and natural gas (natural gas),
And the second reducing agent comprises urea water.
The method according to claim 2,
The first reducing agent comprises methane gas, nitrogen oxide removal equipment.
The method according to claim 1,
And the control unit controls a discharge amount of the first reducing agent discharged from the first reducing agent supply unit to the combustion furnace so that the temperature detected from the temperature detecting unit is 850 ° C to 1100 ° C.
The method according to claim 1,
The control unit compares the nitrogen oxide concentration detected by the gas concentration detection unit with the preset information so that the second reducing agent is discharged from the second reducing agent supply unit to the combustion furnace when the information is higher than the preset information. equipment.
The method according to claim 1,
The control unit compares the carbon monoxide concentration detected by the gas concentration detection unit with the preset information when the first reducing agent is supplied from the first reducing agent supply unit to the combustion furnace, and supplies the same to the heat exchanger when the predetermined information is equal to or greater than the predetermined information. NOx removal plant to increase the supply of air to be added.
The method according to claim 1,
And a preheater for preventing condensation of the second reducing agent discharged from the second reducing agent supply part to the combustion furnace and increasing a vaporization rate.
The method according to claim 7,
And the preheating unit controls the decomposition temperature of the second reducing agent discharged from the second reducing agent supply unit to the combustion furnace to be 350 ° C. or higher.
The method according to claim 1,
The control unit is controlled to supply the second reducing agent after the first reducing agent is first supplied to the combustion furnace, nitrogen oxide removal equipment.
The method according to claim 1,
The control unit is controlled to supply 2 to 3 equivalents of the second reducing agent to 1 equivalent of nitrogen oxide during the initial operation of the nitrogen oxide removal equipment, nitrogen oxide removal equipment.
The method of claim 10, wherein.
The control unit controls to discharge the second reducing agent from the second reducing agent supply unit to the combustion furnace during the initial operation of the nitrogen oxide removal equipment, and blocks the supply of the first reducing agent to the combustion furnace. Removal equipment.
In the nitrogen oxide removal equipment automatic control system using a nitrogen oxide removal equipment according to claim 1,
And the temperature information detected from the temperature detector is compared with predetermined information, and automatically controls the internal temperature of the combustion furnace to be maintained within a preset temperature information range.
The method according to claim 12,
The combustion furnace,
A first combustion chamber supplied with a first reducing agent;
An ignition burner provided in the first combustion chamber;
A second combustion chamber supplied with a second reducing agent; And
An auxiliary burner provided in the second combustion chamber;
Including,
The control unit controls at least one of the ignition burner, the auxiliary burner and the first reducing agent supply unit to automatically control the internal temperature of the combustion furnace, nitrogen oxide removal facility automatic control system.
The method according to claim 12,
The control unit compares the component information and the concentration information of the exhaust gas detected by the gas concentration detection unit with the preset information, and the supply amount of the first reducing agent and the second reducing agent supply unit supplied to the combustion furnace from the first reducing agent supply unit Rotor nitrogen oxide removal equipment automatic control system for controlling at least any one of the supply amount of the second reducing agent supplied to the combustion furnace.

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