KR101989111B1 - Apparatus for Reduction of Nitrogen oxide - Google Patents

Abstract

A nitrogen oxide reduction device according to an embodiment of the present invention includes: a body into which exhaust gas is introduced, and a reducing agent supplier disposed inside the body and supplying a nitrogen oxide reducing agent; Including, wherein the reducing agent supply unit, a reducing agent internal flow path through which the exhaust gas passes therein is formed, and is disposed on the reducing agent internal flow path, and receives heat from the exhaust gas to generate a gas reducing agent It contains a solid reducing agent do.

Description

Nitrogen oxide reduction device {Apparatus for Reduction of Nitrogen oxide}

The present invention relates to a nitrogen oxide reduction device for reducing nitrogen oxide using a solid reducing agent.

Exhaust gas generated when fuel is burned in an internal combustion engine such as a vehicle includes nitrogen oxide (NOx), carbon monoxide (CO), hydrocarbon (HC) gas, and the like. In particular, nitrogen oxides are regulated by the concentration of nitrogen oxides in vehicle exhaust gases in many countries.

In general, as a reduction technology for nitrogen oxides emitted from internal combustion engines, the concentration is reduced by exhaust gas recirculation (EGR) or by reacting nitrogen oxides on a catalyst using ammonia, urea or hydrocarbons as reducing agents to convert nitrogen and oxygen into nitrogen and oxygen. Selective Catalytic Reduction of Nitrogen Oxide, SCR of NOx, etc. are used.

Among the selective catalytic nitrogen oxide reduction methods, the technology using hydrocarbons has the advantage that an additional reducing agent supply device is unnecessary by using the fuel of an internal combustion engine as a reducing agent. There is a disadvantage in that the reduction performance of nitrogen oxides is low.

On the other hand, the technology using liquid urea uses ammonia as a reducing agent. When liquid urea made by dissolving urea, a substance that exists in a solid phase at room temperature in water, is sprayed onto an automobile exhaust pipe, it is thermally decomposed at a temperature of about 150° C. or higher to ammonia ( NH ₃ ). The selective reduction catalyst technology using liquid urea has the advantage of having a wide catalytic reaction temperature range and excellent durability, and can obtain a high nitrogen oxide purification efficiency of about 60 to 80%, but additional devices such as a liquid urea storage container and injection device This has the disadvantage of increasing the weight of the vehicle.

A technology using solid urea (Korean Patent No. 10-1047418, Korean Patent Application Laid-Open No. 10-2012-0045719) has been proposed to compensate for the disadvantages of such liquid urea, but a separate heating unit is required to heat solid urea to generate ammonia Alternatively, there is a problem in that a separate device for injecting powdered solid urea or ammonia into the exhaust pipe is required, thereby increasing the weight of the vehicle.

Korean Patent Publication No. 10-2012-0045719 (published on May 9, 2012) Korean Patent Registration 10-1047418 (published on June 22, 2006)

A first object of the present invention is to provide a nitrogen oxide reduction device using the heat of exhaust gas without a separate heating unit in the process of generating a gas reducing agent from a solid reducing agent.

The conventional nitrogen oxide reduction device has a separate solid reducing agent supply unit to generate a gas reducing agent, and then injecting the generated gas reducing agent into the exhaust gas flow path, or injecting a powdery solid reducing agent into the exhaust gas flow path was used. Since this method requires a separate reducing agent injection device, there is a problem in that the volume and weight of the nitrogen oxide reduction device is increased. The second task is to solve these problems.

The conventional nitrogen oxide reduction device has a problem in that when a solid reducing agent or a gas reducing agent is injected into the exhaust gas flow path, the exhaust gas leaks out of the flow path through the injection pipe, resulting in a pressure loss in the exhaust gas pipe. The third task is to solve these problems.

In the conventional nitrogen oxide reduction device, when the gas reducing agent is excessively supplied, there is a problem that the nitrogen oxide and the unreacted gas reducing agent are discharged to the outside as it is. The fourth task is to solve these problems.

Since the solid reducing agent is gradually consumed while generating the gaseous reducing agent, it must be replaced at a certain period. The conventional nitrogen oxide reduction device has a problem in that it is difficult to know the replacement time of the solid reducing agent. The fifth task is to solve these problems.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

The nitrogen oxide reduction apparatus according to the present invention reduces nitrogen oxides in exhaust gas. In order to solve the above problems, the apparatus for reducing nitrogen oxides according to the present invention includes a body into which exhaust gas is introduced, and a reducing agent supplier disposed inside the body and supplying a nitrogen oxide reducing agent, the reducing agent supplying device comprising: A reducing agent internal flow path through which the exhaust gas passes is formed, and it includes a solid reducing agent disposed on the reducing agent internal flow path to receive heat from the exhaust gas to generate a gas reducing agent.

The nitrogen oxide reduction device may include a catalytic filter. The catalyst filter may have an internal flow path of the catalyst filter, and the internal flow path of the catalyst filter may be formed to have a shape corresponding to that of the reducing agent internal flow path.

The nitrogen oxide reduction device is disposed inside the body, and may include a temperature controller for controlling the temperature of the reducing agent supply unit. The nitrogen oxide reduction device may include a nitrogen oxide sensor. The nitrogen oxide reduction device may include a controller for controlling the temperature controller based on the nitrogen oxide information sensed by the nitrogen oxide sensor.

The nitrogen oxide reduction device may include a gas reducing agent sensor for detecting gas reducing agent information related to the gas reducing agent discharged from the body. The control unit may control the temperature controller based on the gas reducing agent information sensed by the gas reducing agent sensor.

When the nitrogen oxide reduction device determines that the concentration of nitrogen oxides in the exhaust gas discharged from the body is greater than or equal to a preset value, the nitrogen oxide reduction device may control the temperature controller to increase the temperature of the reducing agent supply unit. Even if the controller raises the temperature controller more than a preset value, if it is determined that the concentration of nitrogen oxides in the exhaust gas discharged from the body is more than a preset value, it can generate a replacement signal of the reducing agent supplier.

The nitrogen oxide reduction device may include an auxiliary body in which the reducing agent supplier is disposed, and a main body connected to the auxiliary body and into which the exhaust gas passing through the auxiliary body and the exhaust gas not passing through the auxiliary body are introduced.

The nitrogen oxide reduction device may include an exhaust inflow regulator for controlling exhaust gas flowing into the auxiliary body. It may include a nitrogen oxide sensor for detecting nitrogen oxide information related to nitrogen oxide discharged from the main body. The controller may control the exhaust inflow regulator based on the nitrogen oxide information sensed by the nitrogen oxide sensor.

The nitrogen oxide reduction device includes an outdoor air inlet pipe that has one end connected to the auxiliary body and the other end communicates with the outside and allows outside air to flow into the auxiliary body, an outside air inflow regulator that controls the outside air flowing into the auxiliary body, and discharges from the main body. It may include a gas reducing agent sensor for sensing gas reducing agent information related to the gas reducing agent to be used. The control unit may control the outside air inflow regulator based on the gas reducing agent information sensed by the gas reducing agent sensor.

The details of other embodiments are included in the detailed description and drawings.

In the nitrogen oxide reduction device according to the present invention, a reducing agent supplier is disposed inside the body into which the exhaust gas is introduced, and the reducing agent supplier receives heat directly from the exhaust gas to generate a gas reducing agent, so a separate heating is performed to heat the solid reducing agent no supplements needed Through this, there is an advantage that the volume and weight of the nitrogen oxide reduction device is reduced.

In addition, since an injection device for injecting the reducing agent into the exhaust pipe is not required, the volume and weight of the nitrogen oxide reduction device are reduced, and pressure loss in the exhaust gas pipe generated when the reducing agent is injected is prevented.

The nitrogen oxide reduction device according to the present invention can effectively reduce nitrogen oxides by a selective reduction catalyst nitrogen oxide reduction method including a catalyst filter.

In addition, the shape of the internal flow path of the catalyst filter is formed to correspond to the shape of the internal flow path of the reducing agent so that the exhaust gas flows smoothly, thereby reducing the pressure loss of the exhaust gas in the pipe.

The nitrogen oxide reduction apparatus according to the present invention may detect nitrogen oxide information and control the temperature controller based on the sensed nitrogen oxide information. Through this, there is an advantage in that the nitrogen oxide reduction ability is improved by efficiently controlling the amount of the gas reducing agent generated in the reducing agent supply unit.

The nitrogen oxide reduction device according to the present invention may detect gas reducing agent information and control the temperature controller based on the sensed gas reducing agent information. Through this, there is an advantage in that the amount of the gas reducing agent generated from the reducing agent supply unit is efficiently controlled, and the amount of the gas reducing agent generated more than necessary and discharged to the outside of the vehicle without reacting with nitrogen oxide is reduced.

The nitrogen oxide reduction device according to the present invention, even if the temperature controller is raised more than a preset value, if it is determined that the concentration of nitrogen oxide in the exhaust gas discharged from the body is more than the preset value, it is possible to generate a replacement signal of the reducing agent supplier have. Through this, there is an advantage that the user can easily know the replacement time of the reducing agent supplier.

The nitrogen oxide reduction device according to the present invention includes a main body and an auxiliary body, a reducing agent supplier is disposed inside the auxiliary body, exhaust gas and outside air are introduced into the auxiliary body, and based on the nitrogen oxide information and the gas reducing agent information Exhaust gas and outside air flowing into the auxiliary body can be controlled. Through this, by controlling the temperature of the exhaust gas flowing into the reducing agent supply without a separate temperature controller, there is an advantage that can control the amount of the gas reducing agent generated in the reducing agent supply. In addition, since the temperature of the exhaust gas is controlled by adjusting the exhaust inflow regulator and the outside air inflow regulator, there is an advantage in that the consumed electrical energy or thermal energy is small.

Effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a conceptual diagram of a vehicle in which a nitrogen oxide reduction device according to the present invention is installed.
2 is a conceptual diagram of a nitrogen oxide reduction device according to an embodiment of the present invention.
3 is a control flowchart of a nitrogen oxide reduction device according to an embodiment of the present invention.
4 is a conceptual diagram of a nitrogen oxide reduction device according to another embodiment of the present invention.
5 is a control flowchart of a nitrogen oxide reduction device according to another embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, the exhaust gas generated in the combustion engine and flowing into the exhaust system, the mixed gas of the exhaust gas and the gas reducing agent, and the mixed gas of the exhaust gas and the gas generated by the reaction of the exhaust gas and the gas reducing agent are collectively referred to as “exhaust gas” do.

1 is a conceptual diagram illustrating a vehicle in which a nitrogen oxide reduction device ( ) is installed. 2 and 3 are a conceptual diagram and a control flow diagram of a nitrogen oxide reduction device according to an embodiment of the present invention. 4 and 5 are a conceptual diagram and a control flow diagram of a nitrogen oxide reduction device according to another embodiment of the present invention.

Hereinafter, a nitrogen oxide reduction device 100 according to an embodiment of the present invention will be described with reference to FIG. 1 or less.

Referring to FIG. 1 , reference numeral 2 denotes an internal combustion engine 2 mounted on a vehicle 1 or the like. Fuel is burned in the internal combustion engine 2 and exhaust gas is produced. Exhaust gas includes nitrogen oxide (NO _x ), carbon monoxide (CO), hydrocarbon (HC) gas, and the like. Exhaust gas generated in the internal combustion engine 2 is discharged to the outside of the vehicle 1 or the like through the exhaust system. The exhaust system includes an exhaust pipe 105 through which exhaust gas generated in the internal combustion engine flows. The exhaust system includes an exhaust exhaust pipe 107 through which exhaust gas is discharged to the outside. The exhaust system may include a nitrogen oxide reduction device 100 to reduce exhaust gas. The exhaust system may include a plurality of purification devices including the nitrogen oxide reduction device 100 .

The vehicle 1 provided with the nitrogen oxide reduction device 100 according to the present embodiment includes an internal combustion engine 2 . Exhaust gas generated from the internal combustion engine 2 is introduced into the nitrogen oxide reduction device 100 through the exhaust pipe 105 . The exhaust gas that has passed through the nitrogen oxide reduction device 100 is discharged to the outside of the vehicle 1 through the exhaust discharge pipe 107 .

The nitrogen oxide reduction device 100 according to the present embodiment includes a body 110 into which exhaust gas is introduced. The nitrogen oxide reduction device 100 includes a reducing agent supply unit 130 for supplying a nitrogen oxide reducing agent. The reducing agent supply unit 130 is disposed inside the body 110 . The reducing agent supply unit 130 is formed with a reducing agent internal flow path 135 through which the exhaust gas passes therein. In the reducing agent supply unit 130 , the solid reducing agent 131 is disposed on the reducing agent internal flow path 135 . The solid reducing agent 131 generates a gas reducing agent by receiving heat from the exhaust gas. One side of the nitrogen oxide reduction device 100 is connected to the exhaust pipe 105 so that exhaust gas is introduced. The other side of the nitrogen oxide reduction device 100 is connected to the exhaust discharge pipe 107 to discharge the exhaust gas.

The nitrogen oxide reduction device 100 may include a temperature controller 140 . The temperature controller 140 may adjust the temperature of the solid reducing agent 131 . The nitrogen oxide reduction device 100 may include a catalytic filter 150 . The catalyst filter 150 may provide a catalyst for the reaction of nitrogen oxides and the gas reducing agent. The nitrogen oxide reduction apparatus 100 may include a sensor unit that detects one or more pieces of information related to the nitrogen oxide reduction apparatus 100 . The sensor unit may include a nitrogen oxide sensor 161 that detects nitrogen oxide discharged from the body 110 . The sensor unit may include a gas reducing agent sensor for detecting the gas reducing agent discharged from the body (110). The nitrogen oxide reduction apparatus 100 may include a control unit 160 for controlling one or more functions of the nitrogen oxide reduction apparatus 100 . The controller 160 may control the temperature controller 140 .

The body 110 forms an exterior and is provided with an internal space in which the reducing agent supply unit 130 and the like are accommodated. The body 110 has a reducing agent supply unit 130 is accommodated therein. Body 110 has a temperature controller 140 is accommodated therein. The body 110 accommodates the catalyst filter 150 therein.

The body 110 may be composed of upper and lower rotatable parts. The body 110 may have a structure in which upper and lower parts are detachably coupled, and the reducing agent supply unit 130 and/or the catalyst filter 150 can be replaced.

The body 110 may have a plurality of ribs disposed between the reducing agent supply unit 130 and the catalyst filter 150 . The body 110 may be formed so that the contact surface corresponding to the shape of the reducing agent supplier 130 and the catalyst filter 150 is curved. In the body 110 configured as described above, the flow of the reducing agent supply unit 130 and the catalyst filter 150 is prevented.

The body 110 has an open hole formed on one side thereof and is connected to the exhaust pipe 105 , and exhaust gas is introduced into the body 110 through the exhaust pipe 105 . The body 110 has an open hole formed on the other side thereof and is connected to the exhaust discharge pipe 107 , and exhaust gas is discharged to the outside of the body 110 through the exhaust discharge pipe 107 .

The reducing agent supply unit 130 is disposed inside the body 110 . The reducing agent supply unit 130 includes a solid reducing agent 131 . The reducing agent supply unit 130 supplies a nitrogen oxide reducing agent. The reducing agent supply unit 130 is formed in a honeycomb shape, and the reducing agent internal flow path 135 through which the exhaust gas flows is formed therein. Referring to FIG. 2 , in an embodiment of the present invention, the reducing agent supply unit 130 is composed of only the solid reducing agent 131 . In the reducing agent supply unit 130 , the solid reducing agent 131 forms the shape of the reducing agent supply unit 130 . Although not shown, in another embodiment of the present invention, the reducing agent supply unit 130 is composed of a frame formed of a heterogeneous material, and a solid reducing agent 131 is coated on the frame. The reducing agent supply unit 130 is formed of a heterogeneous material. The reducing agent supply unit 130 is preferably made of a material having good thermal conductivity so that the heat transferred from the exhaust gas is effectively conducted to the solid reducing agent 131 . The reducing agent supply unit 130 may be formed of a ceramic frame having good thermal conductivity. The reducing agent supply unit 130 may be framed with titanium dioxide (TiO2) or the like. Titanium dioxide is known to have a thermal conductivity of 4.8W/(mK) to 11.8W/(mK).

In the solid reducing agent 131, a gas reducing agent is generated by heat, and the generated gas reducing agent reacts with nitrogen oxides to purify nitrogen oxides. The solid reducing agent 131 is a gaseous nitrogen oxide It consists of the solid phase material from which the reducing agent is produced. Typical gaseous nitrogen oxides The reducing agent is ammonia (NH ₃ ). Solid substances from which ammonia is produced include solid ammonium salts, solid urea, and the like.

The solid reducing agent 131 may be a solid urea. However, the solid urea has a high thermal decomposition temperature of about 140° C., and if the pyrolysis temperature cannot be maintained in the reactor and the pipeline, the urea may be solidified in the pipeline or the like. In addition, solid urea produces by-products such as isocyanic acid (HNCO) and cyanuric acid (cyanuric acid) in addition to ammonia in the pyrolysis process, and clogging of pipelines and valves may occur by these by-products.

The reaction equation in which solid urea is thermally decomposed to produce ammonia is as follows.

CO(NH ₂ ) ₂ + H ₂ O → 2NH ₃ + CO ₂

The solid reducing agent 131 may be a solid ammonium salt such as _{ammonium-carbamate (NH 2} COONH ₄ ) or ammonium-carbonate ((NH ₄ ) ₂ CO _{2 ).} Ammonium-carbamate (NH ₂ COONH ₄ ) or ammonium-carbonate ((NH ₄ ) ₂ CO ₂ ) is thermally decomposed into ammonia at about 60° C. Alternatively, a small amount of thermal energy can be used, and there is an advantage in that by-products generated by the decomposition of solid elements are not generated. However, it is difficult to obtain compared to the solid element, and there is a disadvantage that the price is high.

A reaction formula in which ammonium-carbamate and ammonium-carbonate are thermally decomposed to produce ammonia is as follows.

NH ₂ COONH ₄ ↔ 2NH ₃ +CO

(NH ₄ ) ₂ CO ₂ ↔ 2NH ₃ +CO ₂ +H ₂ O

And, when the generated ammonia is mixed with the exhaust gas, the representative reaction equation for purifying nitrogen oxides (nitrogen oxides) on the catalyst filter 150 is as follows.

NO + NO ₂ + 2NH ₃ → 2N ₂ +3H ₂ O

The solid reducing agent 131 is disposed on the reducing agent internal flow path, and is in contact with the exhaust gas. The exhaust gas passes through the reducing agent internal flow path 135 , and the heat of the exhaust gas is transferred to the solid reducing agent 131 , and ammonia is generated from the solid reducing agent 131 by the heat.

Hereinafter, the train reducing agent will be described based on ammonia, but the present invention is not limited thereto.

The reducing agent supply 130 configured in this way has the advantage that the gas reducing agent is generated by the heat of the exhaust gas without a separate heating means. In the prior art, a separate heating device was provided to generate a gas reducing agent from the solid reducing agent 131 . Since the nitrogen oxide reduction device 100 according to the present embodiment does not need to include a separate heating means, the configuration is simplified and the volume of the device is reduced.

Since the reducing agent supply unit 130 according to this embodiment generates a gas reducing agent in the flow path of the exhaust gas without a separate reducing agent injection means, the pressure loss in the pipe through which the exhaust gas passes by the reducing agent injection means does not occur. have.

The reducing agent supply unit 130 is formed in a honeycomb shape to widen the contact area with the exhaust gas passing through the reducing agent internal flow path 135, so that the heat of the exhaust gas is effectively converted into a solid reducing agent 131 on the reducing agent supply unit 130. There are advantages to being transmitted.

The nitrogen oxide reduction device 100 may include a temperature controller 140 . The temperature controller 140 is disposed inside the body 110 . The temperature controller 140 is in contact with at least a portion of the reducing agent supply unit 130 and controls the temperature of the reducing agent supply unit 130 . The thermostat 140 may be a heater and/or a cooler.

Referring to FIG. 2 , the temperature controller 140 is disposed between the reducing agent supply unit 130 and the wall of the body 110 . The temperature controller 140 surrounds the edge of the reducing agent supply unit 130 as viewed from the direction in which the exhaust gas flows into the body 110 and is disposed in contact with the reducing agent supply unit 130 .

The temperature controller 140 controls the temperature of the reducing agent supply unit 130 . When the temperature of the reducing agent supply unit 130 increases, the amount of gas reducing agent generated is increased. When the temperature of the reducing agent supply unit 130 is lowered, the amount of gas reducing agent generated is reduced.

The temperature controller 140 heats the reducing agent supply unit 130 when the heat transferred from the exhaust gas to the reducing agent supply unit 130 is not sufficient, so that an appropriate amount of the gas reducing agent can be generated from the reducing agent supply unit 130. . Through this, the temperature controller 140 provides a sufficient amount of a gas reducing agent to react with nitrogen oxides in the exhaust gas, thereby effectively reducing nitrogen oxides. In addition, the temperature controller 140 maintains the thermal decomposition temperature of the solid reducing agent 131 to prevent the solid reducing agent 131 from coagulating on the flow path to prevent clogging.

The temperature controller 140 cools the reducing agent supply unit 130 when the heat transferred from the exhaust gas to the reducing agent supply unit 130 is excessive, so that an appropriate amount of the gas reducing agent can be generated in the reducing agent supply unit 130 . Through this, the temperature controller 140 provides an appropriate amount of a gas reducing agent to react with nitrogen oxides in the exhaust gas, thereby effectively reducing nitrogen oxides. In addition, the temperature controller 140 has the advantage of preventing the high-pressure gas reducing agent from leaking due to an increase in the internal pressure of the nitrogen oxide reducing device 100 due to excessive generation of the gas reducing agent. On the other hand, the temperature controller 140 has the advantage of preventing the gas reducing agent from being excessively generated and not reacting with nitrogen oxides from being discharged to the outside of the vehicle 1 .

The temperature controller 140 may be controlled by the controller 160 . The temperature controller 140 may include a temperature sensor.

The nitrogen oxide reduction device 100 may include a catalytic filter 150 . The nitrogen oxide reduction apparatus 100 according to this embodiment uses a selective catalytic reduction of nitrogen oxide (SCR of NOx). The selective catalyst nitrogen oxide reduction method is a reaction in which nitrogen oxides are reacted on a catalyst using urea or hydrocarbons to reduce nitrogen and oxygen.

The catalyst filter 150 may include a plurality of catalyst filters 150a and 150b. In the catalytic filter 150 , a plurality of catalytic filters 150a and 150b may be disposed in series on a flow path of the exhaust gas. The plurality of catalytic filters 150a and 150b may be disposed to be in contact with each other. The plurality of catalytic filters 150a and 150b may be formed so that the shapes of the catalytic filter internal flow paths 155 correspond to each other.

The catalyst filter 150 provides a catalyst for the reaction of nitrogen oxides and the gas reducing agent. In this embodiment, the catalytic filter 150 reacts nitrogen oxide with ammonia so that the nitrogen oxide is reduced to harmless nitrogen and water vapor. The catalytic filter 150 is composed of a selective reduction catalyst (SCR). The catalyst filter 150 may be configured by forming a ceramic frame and coating a catalyst material on the frame. As the catalyst material, vanadium pentoxide (V ₂ O ₅ ) or geolite may be used.

The catalytic filter 150 has a catalytic filter internal flow path 155 through which exhaust gas passes. In the catalyst filter 150 , nitrogen oxides and ammonia are introduced into the catalytic filter internal flow path 155 to catalytically react, so that the nitrogen oxides are reduced to harmless nitrogen and water vapor.

The catalytic filter 150 is formed in a honeycomb shape, so that a plurality of flow paths may be formed in the catalytic filter internal flow path 155 . The catalyst filter 150 configured in this way has a large area in which the exhaust gas containing nitrogen oxides and ammonia is in contact with the catalyst filter 150, so that the nitrogen oxides It has the advantage of improving the reduction function.

When the catalytic filter 150 is used, a problem of catalyst poisons in which the internal flow path 155 of the catalytic filter is clogged may occur. The case where the lifespan of the catalyst filter 150 is shortened due to the clogging of the internal flow path 155 of the catalyst filter mainly occurs in a place where the concentration of dust is high. In the catalyst filter 150 , a soot blower may be additionally disposed to prevent clogging of the internal flow path 155 of the catalyst filter. A soot blower is a device that cleans using superheated steam or compressed air, and is used to remove dust or corrosives from boiler facilities.

The catalyst filter 150 is installed downstream of the reducing agent supplier 130 on the exhaust gas flow path. The catalyst filter 150 is disposed behind the reducing agent supply unit 130 . In the catalyst filter 150 , the catalytic filter internal flow path 155 may be formed to correspond to the shape of the reducing agent internal flow path 135 . Through this, the catalytic filter 150 may allow the exhaust gas to smoothly pass through the reducing agent internal flow path 135 and the catalytic filter internal flow path 155 . In the catalytic filter 150 , the catalytic filter internal flow path 155 may be formed in a shape similar to or substantially the same as that of the reducing agent internal flow path 135 inside the solid reducing agent 131 . The catalytic filter 150 configured in this way has the advantage of reducing pressure loss due to a change in the flow of exhaust gas according to the shape of the internal flow path.

Since the nitrogen oxide reduction device 100 configured in this way does not require a separate heating unit to heat the solid reducing agent 131, the volume and weight of the nitrogen oxide reduction device 100 are reduced compared to the prior art. .

In addition, since the nitrogen oxide reduction device 100 does not require a separate device for injecting the gas reducing agent into the flow path of the exhaust gas, the volume and weight of the nitrogen oxide reduction device 100 are reduced compared to the prior art. have.

In addition, since the nitrogen oxide reduction device 100 does not require a separate supply pipe for injecting the gas reducing agent into the flow path of the exhaust gas, there is an advantage in that the pressure loss in the exhaust gas pipe is prevented when the reducing agent is supplied. Since ammonia is generated in the flow path of the exhaust gas in the nitrogen oxide reduction device 100, the pressure in the pipe through which the exhaust gas passes is increased to a certain extent, thereby compensating for pressure loss due to flow friction and the like.

Meanwhile, although not shown, the nitrogen oxide reduction device 100 does not include the catalytic filter 150 and may purify nitrogen oxides using a selective non-catalytic reduction reaction (SNCR).

The nitrogen oxide reduction device 100 may include a sensor unit. The sensor unit detects one or more pieces of information related to the nitrogen oxide reduction device 100 . The sensor unit may include a sensor having one or more functions. Referring to FIG. 2 , the nitrogen oxide reduction device 100 according to the present embodiment includes a nitrogen oxide sensor 161 . The nitrogen oxide reduction device 100 includes an ammonia sensor 163 . The nitrogen oxide reduction device 100 may include a temperature sensor 165 . The nitrogen oxide reduction device 100 may include a pressure sensor 167 .

The nitrogen oxide sensor 161 detects nitrogen oxide information related to nitrogen oxide discharged from the body 110 . The nitrogen oxide sensor 161 may be disposed on the body 110 . The nitrogen oxide sensor 161 may be disposed on the exhaust discharge pipe 107 . Nitrogen oxide is a generic term for nitrogen oxide gas including nitrogen monoxide (NO), nitrogen dioxide (NO ² ) and nitrous oxide (N ^{2 O).}

The nitrogen oxide information includes nitrogen oxides or parameters related to nitrogen oxides. The nitrogen oxide information includes the concentration of nitrogen oxide in the exhaust gas. The nitrogen oxide information includes the presence or absence of nitrogen oxide in the exhaust gas. The nitrogen oxide information includes the gas partial pressure of nitrogen oxide in the exhaust gas. The nitrogen oxide information includes the total amount of nitrogen oxides in the exhaust gas.

The nitrogen oxide sensor 161 may be configured to provide quantitative information such as the concentration, partial pressure, and total amount of nitrogen oxide to the controller 160 . The nitrogen oxide sensor 161 may be configured to provide a signal to the controller 160 when the nitrogen oxide information is greater than or equal to a preset value. The nitrogen oxide sensor 161 may be configured to provide a signal to the controller 160 when the nitrogen oxide information is less than or equal to a preset value. The nitrogen oxide sensor 161 may be configured to provide a signal to the controller 160 when it is detected that nitrogen oxide is present. The nitrogen oxide sensor 161 may be configured to provide a signal to the controller 160 when it is detected that nitrogen oxide does not exist. The nitrogen oxide sensor 161 provides a preset signal to the controller 160 when the nitrogen oxide information is less than or equal to a preset value, and does not provide a preset signal to the controller 160 when the nitrogen oxide information is greater than or equal to a preset value. can be composed of

The nitrogen oxide sensor 161 may be configured as a gas sensor using a mixed potential method. The mixed potential type nitrogen oxide gas sensor includes an oxygen ion conductor formed of a solid electrolyte such as stabilized zirconia, an oxide sensing electrode formed on one side of the oxygen ion conductor, and a first noble metal electrode formed on the oxide sensing electrode , is formed with a second noble metal electrode formed on the other side of the oxygen ion conductor, and the concentration of nitrogen oxide gas is measured by measuring the electromotive force between the first and second noble metal electrodes. In this mixed potential type nitrogen oxide gas sensor, the oxide sensing electrode has reactivity with nitrogen oxide gas and oxygen, but the second noble metal electrode has reactivity only with oxygen. As the principle of generating a potential difference between the second noble metal electrodes 140 is used, the concentration of the nitrogen oxide gas can be measured by measuring the potential difference.

In more detail, in the mixed potential type nitrogen oxide gas sensor, when nitrogen dioxide is present, reactions such as Equations (1) and (2) below occur, and when nitrogen monoxide is present, the following Equation ( 3) and Equation (4) occur.

For NO ₂ : NO ₂ + 2e ^- → NO + O ^{2 -} . . . . . . (One)

O ^2- → 1/2O ₂ + 2e ^- . . . . . . (2)

For NO: NO + O ^2- → NO ₂ + 2e ^- . . . . . . (3)

1/2O ₂ + 2e ^- → O ^{2 -} . . . . . . (4)

The nitrogen oxide sensor 161 may be configured as a gas sensor that measures the nitrogen oxide gas concentration by using the equilibrium potential. This is an electrochemical cell ( By forming an electrochemical cell), the concentration of nitrogen oxide gas is measured using the electromotive force generated in the electrochemical cell.

The nitrogen oxide sensor 161 may be configured as a current-type nitrogen oxide gas sensor. The current-type nitrogen oxide gas sensor converts nitrogen dioxide into nitrogen monoxide using an oxygen pumping cell, and measures the concentration of nitrogen oxide gas by measuring the current by oxygen ions obtained by decomposing the converted nitrogen monoxide in the measurement cell. .

The ammonia sensor 163 detects gas reducing agent information related to the ammonia discharged from the body 110 . The ammonia sensor 163 may be disposed on the body 110 . The ammonia sensor 163 may be disposed on the exhaust discharge pipe 107 .

Ammonia information includes ammonia or parameters related to ammonia. The ammonia information includes the concentration of ammonia in the exhaust gas. The ammonia information includes the presence or absence of ammonia in the exhaust gas. The ammonia information includes the gas partial pressure of ammonia in the exhaust gas. The ammonia information includes the total amount of ammonia in the exhaust gas.

The ammonia sensor 163 may be configured to provide quantitative information such as concentration, partial pressure, and total amount of ammonia to the controller 160 . The ammonia sensor 163 may be configured to provide a signal to the controller 160 when the ammonia information is greater than or equal to a preset value. The ammonia sensor 163 may be configured to provide a signal to the controller 160 when the ammonia information is less than or equal to a preset value. The ammonia sensor 163 may be configured to provide a signal to the controller 160 when it is detected that ammonia is present. The ammonia sensor 163 may be configured to provide a signal to the controller 160 when it is detected that ammonia is not present. The ammonia sensor 163 provides a preset signal to the controller 160 when the ammonia information is less than or equal to a preset value, and does not provide a preset signal to the controller 160 when the ammonia information is greater than or equal to a preset value. can

The ammonia sensor 163 may be configured as a semiconductor type gas sensor. The semiconductor-type gas sensor uses a change in electrical conductivity that occurs when gas comes into contact with a semiconductor surface. As the parent material of the semiconductor gas sensor, a metal oxide stable at high temperature is mainly used. As the metal oxide, tin dioxide (SnO _{2 )} , zinc oxide (ZnO), iron III oxide (Iron(III) oxide, Fe ₂ O ₃ ), etc. are used. The semiconductor-type gas sensor may be configured as a detection method using, as an electrical signal, a change in the electrical conductivity of a semiconductor and a change in the combined resistance between the platinum wire coil and the semiconductor when ammonia gas is adsorbed to the sensor. The semiconductor-type gas sensor has advantages of excellent sensitivity, simple structure, miniaturization and good long-term stability. However, the semiconductor-type gas sensor has a problem in that the resistance, sensitivity, reaction speed, and recovery speed of the sensor are greatly reduced due to changes in humidity or temperature.

The ammonia sensor 163 may be configured as an electrochemical gas sensor. The ammonia sensor 163 may be configured as a non-dispersive infrared gas sensor.

The nitrogen oxide reduction device 100 may include a temperature sensor 165 . The temperature sensor 165 detects temperature information related to the nitrogen oxide reduction device 100 . The temperature sensor 165 may be disposed on the temperature controller 140 to detect the temperature of the reducing agent supply unit 130 .

The temperature information includes the temperature of one or more components among the components of the nitrogen oxide reduction device 100 . The temperature information includes the temperature of the reducing agent supply unit (130). The temperature information includes a temperature at a certain point in time. The temperature information includes an amount of temperature change over a period of time. The temperature information includes a rate of temperature change over a period of time.

The temperature sensor 165 may provide quantitative temperature information, such as temperature, temperature change amount, and temperature change rate, to the controller 160 . The temperature sensor 165 may provide a signal to the controller 160 when the temperature is equal to or greater than a preset value. The temperature sensor 165 may be configured to provide a preset signal to the controller 160 when the temperature is less than or equal to a preset value, and block the preset signal to the controller 160 when the temperature is greater than or equal to a preset value.

The nitrogen oxide reduction device 100 may include a pressure sensor 167 . The pressure sensor 167 senses pressure information related to the nitrogen oxide reduction device 100 . The pressure sensor 167 may be disposed on the body 110 to sense the pressure inside the body 110 .

The pressure information includes pressure in one or more components among the components of the nitrogen oxide reduction device 100 . The pressure information includes the temperature inside the body 110 . The pressure information includes pressure at a certain point in time. The pressure information includes an amount of pressure change over a period of time. The pressure information includes a rate of pressure change over a period of time.

The pressure sensor 167 may provide quantitative pressure information to the controller 160 . The pressure sensor 167 may provide a signal to the controller 160 when the pressure is equal to or greater than a preset value. The pressure sensor 167 may be configured to provide a preset signal to the controller 160 when the pressure is less than or equal to a preset value, and block a preset signal to the controller 160 when the pressure is greater than or equal to a preset value.

Hereinafter, the control unit 160 and the control method of the nitrogen oxide reduction apparatus 100 according to the present embodiment will be described with reference to FIGS. 2 and 3 .

The nitrogen oxide reduction device 100 may include a control unit 160 . The controller 160 may control one or more functions of the nitrogen oxide reduction device 100 . The control unit 160 may control one or more functions of the nitrogen oxide reduction device 100 based on the information sensed by the sensor unit. The information sensed by the sensor unit includes nitrogen oxide information. The information sensed by the sensor unit includes ammonia information. The information sensed by the sensor unit may include temperature information of the reducing agent supply unit 130 . The information sensed by the sensor unit may include exhaust gas pressure information inside the body 110 .

The controller 160 controls the temperature controller 140 based on the nitrogen oxide information sensed by the nitrogen oxide sensor 161 .

The nitrogen oxide information includes nitrogen oxides or parameters related to nitrogen oxides. The nitrogen oxide information includes the concentration of nitrogen oxide in the exhaust gas. The nitrogen oxide information includes the presence or absence of nitrogen oxide in the exhaust gas. The nitrogen oxide information includes the gas partial pressure of nitrogen oxide in the exhaust gas. The nitrogen oxide information includes the total amount of nitrogen oxides in the exhaust gas.

The controller 160 may be configured to determine whether the nitrogen oxide information is equal to or less than a preset value, and to control the temperature controller 140 . When the nitrogen oxide sensor 161 provides a signal, the control unit 160 may be configured to control the temperature controller 140 so that the temperature of the reducing agent supply unit 130 rises or falls. When the nitrogen oxide sensor 161 provides a signal, the controller 160 does not determine whether the nitrogen oxide information is above or below a preset value, and the temperature of the reducing agent supply unit 130 increases or decreases. can be configured to control

If the nitrogen oxide information detected by the nitrogen oxide sensor 161 is greater than or equal to a preset value, the controller 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . When the nitrogen oxide sensor 161 provides a signal when the nitrogen oxide information is equal to or greater than a preset value, the controller 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . When the nitrogen oxide sensor 161 detects that nitrogen oxide is present, the control unit 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . When the control unit 160 provides a signal when the nitrogen oxide sensor 161 detects that nitrogen oxide is present, the control unit 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . The nitrogen oxide sensor 161 provides a preset signal to the controller 160 when the nitrogen oxide information is less than or equal to a preset value, and is configured not to provide a preset signal to the controller 160 when the nitrogen oxide information is greater than or equal to a preset value. It may be, and the control unit 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 when a preset signal is not provided.

If the nitrogen oxide information sensed by the nitrogen oxide sensor 161 is less than or equal to a preset value, the controller 160 may control the temperature controller 140 to lower the temperature of the reducing agent supply unit 130 . When the nitrogen oxide sensor 161 provides a signal when the nitrogen oxide information is less than or equal to a preset value, the controller 160 may control the temperature controller 140 to lower the temperature of the reducing agent supply unit 130 . When the nitrogen oxide sensor 161 detects that the nitrogen oxide does not exist, the controller 160 may control the temperature controller 140 so that the temperature of the reducing agent supply unit 130 is lowered. When the control unit 160 provides a signal when the nitrogen oxide sensor 161 detects that nitrogen oxide does not exist, the control unit 160 may control the temperature controller 140 to lower the temperature of the reducing agent supply unit 130 . The nitrogen oxide sensor 161 provides a preset signal to the controller 160 when the nitrogen oxide information is greater than or equal to a preset value, and is configured not to provide a preset signal to the controller 160 when the nitrogen oxide information is less than or equal to a preset value. It may be, and the control unit 160 may control the temperature controller 140 so that the temperature of the reducing agent supply unit 130 is lowered if a preset signal is not provided.

The control unit 160 may be configured to generate a replacement signal of the reducing agent supply unit 130 when the nitrogen oxide is detected, and the temperature controller 140 is above a certain temperature. The control unit 160 configured in this way has the advantage that the user can easily know the replacement time of the reducing agent supply unit (130).

The controller 160 controls the temperature controller 140 based on the ammonia information detected by the ammonia sensor 163 .

Ammonia information includes ammonia or parameters related to ammonia. The ammonia information includes the concentration of ammonia in the exhaust gas. The ammonia information includes the presence or absence of ammonia in the exhaust gas. The ammonia information includes the gas partial pressure of ammonia in the exhaust gas. The ammonia information includes the total amount of ammonia in the exhaust gas.

The control unit 160 may be configured to determine whether the ammonia information is above or below a preset value, and to control the temperature controller 140 . When the ammonia sensor 163 provides a signal, the control unit 160 may be configured to control the temperature controller 140 so that the temperature of the reducing agent supply unit 130 rises or falls. When the ammonia sensor 163 provides a signal, the control unit 160 controls the temperature controller 140 to increase or decrease the temperature of the reducing agent supply unit 130 without determining whether the ammonia information is above or below a preset value. can be configured to

If the ammonia information sensed by the ammonia sensor 163 is greater than or equal to a preset value, the controller 160 may control the temperature controller 140 to lower the temperature of the reducing agent supply unit 130 . When the ammonia sensor 163 provides a signal when the ammonia information is equal to or greater than a preset value, the controller 160 may control the temperature controller 140 to lower the temperature of the reducing agent supply unit 130 . When the ammonia sensor 163 detects that ammonia is present, the control unit 160 may control the temperature controller 140 to lower the temperature of the reducing agent supply unit 130 . When the ammonia sensor 163 provides a signal when it is detected that ammonia is present, the control unit 160 may control the temperature controller 140 so that the temperature of the reducing agent supply unit 130 is lowered. The ammonia sensor 163 may be configured not to provide a preset signal to the controller 160 when the ammonia information is less than or equal to a preset value, and not to provide a preset signal to the controller 160 when the ammonia information is greater than or equal to a preset value. , the control unit 160 may control the temperature controller 140 so that the temperature of the reducing agent supply 130 is lowered if a preset signal is not provided.

If the ammonia information detected by the ammonia sensor 163 is less than or equal to a preset value, the controller 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . When the ammonia sensor 163 provides a signal when the ammonia information is less than or equal to a preset value, the controller 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . When the ammonia sensor 163 detects that ammonia does not exist, the control unit 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . When the ammonia sensor 163 provides a signal when it is detected that ammonia does not exist, the control unit 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . The nitrogen oxide sensor 161 provides a preset signal to the controller 160 when the nitrogen oxide information is greater than or equal to a preset value, and is configured not to provide a preset signal to the controller 160 when the nitrogen oxide information is less than or equal to a preset value. It may be, the control unit 160 may control the temperature controller 140 so that the temperature of the reducing agent supply 130 rises when a preset signal is not provided.

The control unit 160 may be configured to generate a replacement signal of the reducing agent supply unit 130, when nitrogen oxide is detected, ammonia is not detected, and the temperature controller 140 is above a certain temperature. Since the reducing agent supply unit 130 consumes the solid reducing agent 131 as ammonia is generated from the solid reducing agent 131, the reducing agent supply unit 130 must be replaced at a certain period. The control unit 160 configured in this way has the advantage that the user can easily know the replacement time of the reducing agent supply unit (130).

The controller 160 may be configured to generate a replacement signal for the catalyst filter 150 when nitrogen oxide is detected, ammonia is detected, and the temperature controller 140 is above a predetermined temperature. When nitrogen oxide and ammonia do not react and are discharged to the outside, it can be seen that a catalyst suitable for the reaction of nitrogen oxide and gas reducing agent is not provided. The control unit 160 configured in this way has the advantage that the user can easily know when to replace the catalyst filter 150 .

When ammonia is not sufficiently supplied from the nitrogen oxide reduction device 100 , nitrogen oxides that do not react with ammonia are discharged to the outside of the vehicle 1 through the exhaust discharge pipe 107 . On the other hand, when ammonia is excessively supplied from the nitrogen oxide reduction device 100 , ammonia that has not reacted with nitrogen oxide is discharged to the outside of the vehicle 1 through the exhaust discharge pipe 107 .

Since the nitrogen oxide reduction device 100 configured in this way adjusts to generate an appropriate amount of ammonia, which is a gas reducing agent, there is an advantage in that nitrogen oxides are effectively reduced. In addition, there is an advantage in that the amount of ammonia discharged to the outside of the vehicle 1 is reduced.

On the other hand, since the nitrogen oxide reduction device 100 informs the replacement time of the reducing agent supply unit 130, there is also an advantage that the replacement of the reducing agent supply unit 130 is facilitated.

The controller 160 may control the temperature controller 140 based on the temperature information sensed by the temperature sensor 165 .

The temperature information includes the temperature of one or more components among the components of the nitrogen oxide reduction device 100 . The temperature information includes the temperature of the reducing agent supply unit (130). The temperature information includes a temperature at a certain point in time. The temperature information includes an amount of temperature change over a period of time. The temperature information includes a rate of temperature change over a certain period of time.

The controller 160 may be configured to determine whether the temperature information is above or below a preset value, and to control the temperature controller 140 . When the temperature sensor 165 provides a signal, the control unit 160 may be configured to control the temperature controller 140 so that the temperature of the reducing agent supply unit 130 rises or falls. When the temperature sensor 165 provides a signal, the control unit 160 controls the temperature controller 140 to increase or decrease the temperature of the reducing agent supply unit 130 without determining whether the temperature information is above or below a preset value. can be configured to

The control unit 160 may be configured to generate a replacement signal of the reducing agent supply unit 130 when the nitrogen oxide is sensed, and the temperature of the reducing agent supply unit 130 is above a certain temperature. The control unit 160 may be configured to generate a replacement signal of the reducing agent supply unit 130 when the nitrogen oxide information is greater than or equal to a preset value, and the temperature of the reducing agent supply unit 130 is above a certain temperature.

When the temperature of the reducing agent supply unit 130 is below a certain temperature, the control unit 160 may control the temperature controller 140 to increase the temperature of the reducing agent supply unit 130 . The control unit 160 configured as described above causes the gas reducing agent to be generated in the reducing agent supply unit 130 even when sufficient heat is not transferred from the exhaust gas to the reducing agent supply unit 130 at the initial stage when the internal combustion engine is driven. Nitrogen oxide can be reduced.

The controller 160 may control the temperature controller 140 based on the pressure information sensed by the pressure sensor 167 .

The pressure information includes pressure in one or more components among the components of the nitrogen oxide reduction device 100 . The pressure information includes the temperature inside the body 110 . The pressure information includes pressure at a certain point in time. The pressure information includes an amount of pressure change over a period of time. The pressure information includes a rate of pressure change over a period of time.

The control unit 160 may be configured to determine whether the pressure information is equal to or greater than a preset value, and to control the temperature controller 140 . When the pressure sensor 167 provides a signal, the control unit 160 may be configured to control the temperature controller 140 so that the temperature of the reducing agent supply 130 rises or falls. When the pressure sensor 167 provides a signal, the control unit 160 controls the temperature controller 140 to increase or decrease the temperature of the reducing agent supply unit 130 without determining whether the pressure information is above or below a preset value. can be configured to

If the pressure in the body 110 is greater than or equal to a certain pressure, the control unit 160 may control the temperature controller 140 to lower the temperature of the reducing agent supply unit 130 . The control unit 160 configured in this way is to prevent a problem in the nitrogen oxide reduction device 100 such as excessive supply of the gas reducing agent in the body 110, leakage of the gas reducing agent or changing the shape of the body 110. can

Hereinafter, with reference to FIGS. 4 and 5 , the nitrogen oxide reduction device 200 according to another embodiment of the present invention will be mainly described with respect to parts different from the one embodiment.

In this embodiment, the nitrogen oxide reduction device 200 includes a main body 211 and a sub-body 212 . The sub-body 212 has a reducing agent supplier 230 disposed therein. The main body 211 is connected to the sub-body 212 , and exhaust gas passing through the sub-body 212 flows into the main body 211 . Exhaust gas that has not passed through the sub-body 212 is introduced into the main body 211 .

In the nitrogen oxide reduction device 200 according to the present embodiment, the exhaust gas generated in the internal combustion engine and flowing along the exhaust pipe is separated from the first branch 217 . A portion of the exhaust gas flows directly into the main body 211 , and a portion flows into the main body 211 after passing through the sub-body 212 .

The nitrogen oxide reduction device 200 includes a sub exhaust pipe 221 that is separated from the exhaust pipe 205 and extends. The sub exhaust pipe 221 is separated from the exhaust pipe 205 in the first branch 217 . The sub exhaust pipe 221 connects the exhaust pipe 205 and the sub body 212 . Some of the exhaust gas flowing along the exhaust pipe is introduced into the sub body 212 through the sub exhaust pipe 221 . The sub exhaust pipe 221 may be formed to extend perpendicularly to the exhaust pipe. The sub exhaust pipe 221 may form a predetermined angle with the exhaust pipe and extend in a direction inclined in the flow direction of the exhaust gas.

The nitrogen oxide reduction device 200 includes an outdoor air inlet pipe 223 . One end of the outdoor air inlet pipe 223 is connected to the sub-body 212 . The outside air inlet pipe 223 has the other end in communication with the outside, and allows outside air to flow into the sub-body 212 . Outside air flowing into the sub-body 212 is mixed with the exhaust gas and lowers the temperature of the exhaust gas, thereby reducing the heat transferred from the exhaust gas to the reducing agent supply unit 230, and reducing the amount of ammonia generated by the reducing agent supply unit 230. Reduce.

The nitrogen oxide reduction device 200 includes a reducing agent supply pipe (225). The reducing agent supply pipe 225 connects the sub-body 212 and the main body 211 so that the exhaust gas passing through the sub-body 212 flows into the main body 211 . The reducing agent supply pipe 225 is connected to the main body 211 in the second branch 219 . The gas reducing agent generated by the reducing agent supply unit 230 inside the sub-body 212 is introduced into the main body 211 through the reducing agent supply pipe 225 . The gas generated by the reaction between the exhaust gas and the gas reducing agent inside the sub body 212 is introduced into the main body 211 through the reducing agent supply pipe 225 . The reducing agent supply pipe 225 may include a supply means for effectively supplying the gas reducing agent to the main body 211 . The supply means may be a mechanism for applying pressure to the gas reducing agent.

The sub-body 212 has a reducing agent supplier 230 disposed therein. The outdoor air introduced into the sub-body 212 through the outdoor air inlet pipe 223 is mixed with the exhaust gas introduced through the sub-exhaust pipe 221 in the sub-body 212 to lower the temperature of the exhaust gas.

The sub-body 212 may be formed of rotatable upper and lower parts. The sub-body 212 may have a structure in which the upper and lower parts are detachably coupled, and the reducing agent supply unit 230 can be replaced.

The sub-body 212 is formed to correspond to the shape of the reducing agent supply unit 230, so that the flow of the reducing agent supply unit 230 is prevented.

The sub-body 212 has an open hole formed on one side thereof to be connected to the sub-exhaust pipe 221 , and exhaust gas is introduced into the sub-body 212 . The sub-body 212 has another open hole formed on one side thereof to be connected to the outdoor air inlet pipe 223 , and external air may be introduced into the sub-body 212 . The sub-body 212 may have an open hole formed on the other side thereof to be connected to the outdoor air inlet pipe 223 . The sub-body 212 has an open hole formed on the other side thereof, is connected to the reducing agent supply pipe 225, and exhaust gas is discharged.

The reducing agent supply unit 230 is disposed inside the sub-body 212 . The reducing agent supply unit 230 may be formed in a honeycomb shape, but is not limited thereto. The reducing agent supply unit 230 may form a solid reducing agent in the shape of the reducing agent supply unit 230 . The reducing agent supply unit 230 may be configured by coating a solid reducing agent on a frame formed of a heterogeneous material.

The main body 211 is connected to the sub-body 212 , and exhaust gas passing through the sub-body 212 flows into the main body 211 . Exhaust gas that has not passed through the sub-body 212 is introduced into the main body 211 . The main body 211 may have a catalyst filter 250 disposed therein.

The main body 211 may be formed of rotatable upper and lower parts. The main body 211 may have a structure in which upper and lower parts are detachably coupled, and the catalyst filter 250 can be replaced.

The main body 211 may be formed to correspond to the shape of the catalyst filter 250 . In the main body 211 , a plurality of ribs may be formed between the plurality of catalyst filters 250 . The main body 211 configured in this way may prevent the catalytic filter 250 from flowing.

The main body 211 has an open hole formed on one side thereof and is connected to the exhaust pipe 205 through which exhaust gas is introduced.

The main body 211 is connected to the reducing agent supply pipe 225 by forming another open hole on the one side. The main body 211 is connected to the reducing agent supply pipe 225 is formed with an open hole on the other side. Exhaust gas passing through the sub-body 212 may be introduced into the main body 211 through the reducing agent supply pipe 225 . The gas reducing agent generated in the sub-body 212 may be introduced into the main body 211 through the reducing agent supply pipe 225 . A product generated by the reaction of nitrogen oxide and a gas reducing agent in the sub body 212 may be introduced into the main body 211 through the reducing agent supply pipe 225 .

The main body 211 has an open hole formed on the other side thereof, is connected to the exhaust discharge pipe 207, and exhaust gas is discharged.

The nitrogen oxide reduction device 200 may include a catalytic filter 250 . The catalytic filter 250 has a catalytic filter internal flow path 255 through which exhaust gas passes. The catalyst filter 250 is installed downstream of the reducing agent supply 230 on the flow path of the exhaust gas. The catalyst filter 250 is disposed inside the main body 211 .

The catalytic filter 250 may be formed in a honeycomb shape, and a plurality of flow paths may be formed in the catalytic filter internal flow path 255 . The catalyst filter 250 configured in this way has a large area in which the exhaust gas containing nitrogen oxides and ammonia is in contact with the catalyst filter 250, and thus has the advantage of improving the nitrogen oxide reduction function.

Meanwhile, although not shown, the nitrogen oxide reduction device 200 does not include the catalytic filter 250 and may purify nitrogen oxides using a selective non-catalytic reduction reaction (SNCR).

The nitrogen oxide reduction device 200 may include a sensor unit. The sensor unit detects one or more pieces of information related to the nitrogen oxide reduction device 200 . The sensor unit may include a sensor having one or more functions. Referring to FIG. 4 , the nitrogen oxide reduction device 200 according to the present embodiment includes a nitrogen oxide sensor 261 . The nitrogen oxide reduction device 200 includes an ammonia sensor 263 . The nitrogen oxide reduction device 200 may include a temperature sensor 265 . The nitrogen oxide reduction device 200 may include a pressure sensor 267 .

The nitrogen oxide sensor 261 senses nitrogen oxide information related to nitrogen oxide discharged from the main body 211 . The nitrogen oxide sensor 261 may be disposed on the main body 211 . The nitrogen oxide sensor 261 may be disposed on the exhaust discharge pipe 207 .

The ammonia sensor 263 detects gas reducing agent information related to the ammonia discharged from the main body 211 . The ammonia sensor 263 may be disposed on the main body 211 . The ammonia sensor 263 may be disposed on the exhaust discharge pipe 207 .

The nitrogen oxide reduction device 200 may include a pressure sensor 267 . The pressure sensor 267 senses pressure information related to the nitrogen oxide reduction device 200 . The pressure sensor 267 may be disposed on the main body 211 to sense the pressure inside the main body 211 . The pressure sensor 267 may be disposed on the sub-body 212 to sense a pressure inside the sub-body 212 .

The nitrogen oxide reduction device 200 may include an exhaust inflow regulator 271 . The exhaust inflow regulator 271 may be a control damper that opens or closes at least a portion of the internal flow space of the sub exhaust pipe 221 .

The exhaust inflow regulator 271 is disposed in the sub exhaust pipe 221 , and controls exhaust gas flowing into the sub body 212 through the sub exhaust pipe 221 . The exhaust inflow regulator 271 may adjust the flow rate of exhaust gas passing through the exhaust inflow regulator 271 . Here, the flow rate may be the volume of the fluid passing through the cross-sectional area per unit time or the mass of the fluid passing through the cross-sectional area per unit time.

The exhaust inflow regulator 271 regulates the exhaust gas flowing into the sub-body 212, thereby controlling the heat transferred from the exhaust gas path to the reducing agent supply unit 230, thereby controlling the gas reducing agent generated in the reducing agent supply unit 230. have. When the exhaust inflow regulator 271 is opened and the amount of exhaust gas flowing into the sub-body 212 increases, the amount of heat transferred to the reducing agent supply 230 is also increased, and the amount of gas reducing agent generated by the reducing agent supply 230 is increased. this is increased When the exhaust inflow regulator 271 is closed and the amount of exhaust gas flowing into the sub-body 212 is reduced, the amount of heat transferred to the reducing agent supply unit 230 is also reduced, and the amount of gas reducing agent generated in the reducing agent supply unit 230 is reduced. This is reduced.

The exhaust inflow regulator 271 may be adjusted based on information sensed by the sensor unit. When a signal is provided from the sensor unit, the exhaust inflow regulator 271 may be configured to open or close the exhaust inflow regulator 271 . The exhaust inflow regulator 271 may be controlled by the controller 260 .

The nitrogen oxide reduction device 200 may include an outside air inflow regulator 273 . The outdoor air inflow regulator 273 may be a control damper that opens or closes at least a portion of the internal flow space of the outdoor air inlet pipe 223 . The outdoor air inlet regulator 273 is disposed on the outdoor air inlet pipe 223 to control the outdoor air flowing into the sub-body 212 through the outdoor air inlet pipe 223 . The outdoor air inflow controller 273 may adjust the flow rate of the outdoor air passing through the outdoor air inflow controller 273 . Here, the flow rate may be the volume of the fluid passing through the cross-sectional area per unit time or the mass of the fluid passing through the cross-sectional area per unit time.

The outdoor air inflow controller 273 may be adjusted based on information sensed by the sensor unit. When a signal is provided from the sensor unit, the outside air inflow regulator 273 may be configured to open or close the outside air inflow regulator 273 . The outdoor air inflow regulator 273 may be controlled by the controller 260 .

Hereinafter, the control unit 260 and the control method of the nitrogen oxide reduction apparatus 200 according to the present embodiment will be described with reference to FIGS. 4 and 5 .

The nitrogen oxide reduction device 200 may include a control unit 260 . The control unit 260 may control one or more functions of the nitrogen oxide reduction device 200 based on the information sensed by the sensor unit.

The controller 260 controls the exhaust inflow regulator 271 . The controller 260 controls the exhaust inflow regulator 271 based on the nitrogen oxide information sensed by the nitrogen oxide sensor 261 . The control unit 260 controls the exhaust inflow regulator 271 based on the ammonia information detected by the ammonia sensor 263 . The controller 260 may control the exhaust inflow regulator 271 based on the temperature information sensed by the temperature sensor 265 . The controller 260 may control the exhaust inflow regulator 271 based on the pressure information sensed by the pressure sensor 267 .

The controller 260 may be configured to determine whether the nitrogen oxide information is equal to or greater than a preset value, and to control the exhaust inflow regulator 271 . When the nitrogen oxide sensor 261 provides a signal, the controller 260 may be configured to control the exhaust inflow regulator 271 to increase or decrease the flow rate of exhaust gas flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal, the controller 260 increases or decreases the flow rate of the exhaust gas flowing into the sub-body 212 without determining whether the nitrogen oxide information is greater than or less than a preset value. It can be configured to control the exhaust inlet regulator 271 to be.

When the nitrogen oxide information detected by the nitrogen oxide sensor 261 is greater than or equal to a preset value, the controller 260 may control the exhaust inflow regulator 271 to increase the flow rate of exhaust gas flowing into the sub-body 212 . . When the nitrogen oxide sensor 261 provides a signal when the nitrogen oxide information is equal to or greater than a preset value, the controller 260 controls the exhaust inflow regulator 271 to increase the flow rate of exhaust gas flowing into the sub-body 212 . can do. When the nitrogen oxide sensor 261 detects that nitrogen oxide is present, the controller 260 may control the exhaust inflow regulator 271 to increase the flow rate of exhaust gas flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal when it is detected that nitrogen oxide is present, the controller 260 controls the exhaust inflow regulator 271 to increase the flow rate of exhaust gas flowing into the sub-body 212 . can do. The nitrogen oxide sensor 261 provides a preset signal to the controller 260 when the nitrogen oxide information is less than or equal to a preset value, and is configured not to provide a preset signal to the controller 260 when the nitrogen oxide information is greater than or equal to a preset value. If the preset signal is not provided, the controller 260 may control the exhaust inflow regulator 271 to increase the flow rate of the exhaust gas flowing into the sub-body 212 .

When the nitrogen oxide information detected by the nitrogen oxide sensor 261 is less than or equal to a preset value, the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of exhaust gas flowing into the sub-body 212 . . When the nitrogen oxide sensor 261 provides a signal when the nitrogen oxide information is less than or equal to a preset value, the controller 260 controls the exhaust inflow regulator 271 to reduce the flow rate of exhaust gas flowing into the sub-body 212 . can do. When the nitrogen oxide sensor 261 detects that nitrogen oxide does not exist, the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of exhaust gas flowing into the sub-body 212 . When the control unit 260 provides a signal when the nitrogen oxide sensor 261 detects that nitrogen oxide does not exist, the control unit 260 controls the exhaust inflow regulator 271 to reduce the flow rate of exhaust gas flowing into the sub-body 212 . can be controlled The nitrogen oxide sensor 261 provides a preset signal to the control unit 260 when the nitrogen oxide information is greater than or equal to a preset value, and is configured not to provide a preset signal to the controller 260 when the nitrogen oxide information is less than or equal to a preset value If the preset signal is not provided, the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of the exhaust gas flowing into the sub-body 212 .

The control unit 260 may be configured to generate a replacement signal of the reducing agent supply unit 230 when nitrogen oxide is detected and the exhaust inflow regulator 271 is adjusted to a preset value or more. The control unit 260 may be configured to generate a replacement signal of the reducing agent supply unit 230 when the nitrogen oxide is detected, and the exhaust inflow regulator 271 is adjusted so that the exhaust gas inflow is maximized. The control unit 260 configured in this way has the advantage that the user can easily know the replacement time of the reducing agent supply unit (230).

The control unit 260 may be configured to determine whether the ammonia information is above or below a preset value, and to control the exhaust inflow regulator 271 . When the ammonia sensor 263 provides a signal, the controller 260 may be configured to control the exhaust inflow regulator 271 to increase or decrease the flow rate of exhaust gas flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal, the controller 260 increases or decreases the flow rate of the exhaust gas flowing into the sub-body 212 without determining whether the nitrogen oxide information is greater than or less than a preset value. It can be configured to control the exhaust inlet regulator 271 to be.

When the ammonia information detected by the ammonia sensor 263 is equal to or greater than a preset value, the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of the exhaust gas flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when the ammonia information is equal to or greater than a preset value, the control unit 260 may control the exhaust inflow regulator 271 to reduce the flow rate of exhaust gas flowing into the sub-body 212 . have. When the ammonia sensor 263 detects that ammonia is present, the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of the exhaust gas flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when it is detected that ammonia is present, the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of exhaust gas flowing into the sub-body 212 . have. The ammonia sensor 263 provides a preset signal to the control unit 260 when the ammonia information is less than or equal to a preset value, and may be configured not to provide a preset signal to the controller 260 when the ammonia information is greater than or equal to a preset value. , the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of exhaust gas flowing into the sub-body 212 when a preset signal is not provided.

When the ammonia information detected by the ammonia sensor 263 is less than or equal to a preset value, the controller 260 may control the exhaust inflow regulator 271 to increase the flow rate of the exhaust gas flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when the ammonia information is less than or equal to a preset value, the control unit 260 may control the exhaust inflow regulator 271 to increase the flow rate of the exhaust gas flowing into the sub-body 212 . have. When the ammonia sensor 263 detects that ammonia does not exist, the controller 260 may control the exhaust inflow regulator 271 to increase the flow rate of the exhaust gas flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when it is detected that ammonia does not exist, the control unit 260 controls the exhaust inflow regulator 271 to increase the flow rate of the exhaust gas flowing into the sub-body 212 . can The ammonia sensor 263 may be configured not to provide a preset signal to the control unit 260 when the ammonia information is greater than or equal to a preset value, and not to provide a preset signal to the controller 260 when the ammonia information is less than or equal to a preset value. , when a preset signal is not provided, the controller 260 may control the exhaust inflow regulator 271 to increase the flow rate of exhaust gas flowing into the sub-body 212 .

The controller 260 may control the exhaust inflow regulator 271 based on the temperature information sensed by the temperature sensor 265 .

The controller 260 may be configured to determine whether the temperature information is equal to or greater than a preset value, and to control the exhaust inflow regulator 271 . When the temperature sensor 265 provides a signal, the controller 260 may be configured to control the exhaust inflow regulator 271 to increase or decrease the flow rate of exhaust gas flowing into the sub-body 212 . When the temperature sensor 265 provides a signal, the controller 260 exhausts the exhaust gas to increase or decrease the flow rate of the exhaust gas flowing into the sub-body 212 without determining whether the temperature information is above or below a preset value. It may be configured to control the inflow regulator 271 .

The control unit 260 may be configured to generate a replacement signal of the reducing agent supply unit 230 when the nitrogen oxide is detected, and the temperature of the reducing agent supply unit 230 is above a certain temperature. The control unit 260 may be configured to generate a replacement signal of the reducing agent supply unit 230 when the nitrogen oxide information is greater than or equal to a preset value, and the temperature of the reducing agent supply unit 230 is above a certain temperature.

The controller 260 may control the exhaust inflow regulator 271 based on the pressure information sensed by the pressure sensor 267 .

The control unit 260 may be configured to determine whether the pressure information is equal to or greater than a preset value, and to control the exhaust inflow regulator 271 . When the pressure sensor 267 provides a signal, the controller 260 may be configured to control the exhaust inflow regulator 271 to increase or decrease the flow rate of exhaust gas flowing into the sub-body 212 . When the pressure sensor 267 provides a signal, the control unit 260 exhausts the exhaust gas to increase or decrease the flow rate of the exhaust gas flowing into the sub-body 212 without determining whether the pressure information is above or below a preset value. It may be configured to control the inflow regulator 271 .

When the pressure in the main body 211 is equal to or greater than a predetermined pressure, the controller 260 may control the exhaust inflow regulator 271 to reduce the flow rate of the exhaust gas flowing into the sub-body 212 . The control unit 260 configured in this way prevents a problem in the nitrogen oxide reduction device 200 such as excessive supply of the gas reducing agent in the main body 211, leakage of the gas reducing agent or the shape of the main body 211 is changed. can be prevented

The control unit 260 controls the outside air inflow regulator 273 . The controller 260 controls the outside air inflow regulator 273 based on the nitrogen oxide information sensed by the nitrogen oxide sensor 261 . The control unit 260 controls the outdoor air inflow regulator 273 based on the ammonia information detected by the ammonia sensor 263 . The controller 260 may control the outdoor air inflow controller 273 based on the temperature information sensed by the temperature sensor 265 . The controller 260 may control the outdoor air inflow regulator 273 based on the pressure information sensed by the pressure sensor 267 .

The controller 260 may be configured to determine whether the nitrogen oxide information is equal to or greater than a preset value, and to control the outdoor air inflow controller 273 . When the nitrogen oxide sensor 261 provides a signal, the control unit 260 may be configured to control the outside air inflow regulator 273 to increase or decrease the flow rate of outside air flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal, the control unit 260 increases or decreases the flow rate of external air flowing into the sub-body 212 without determining whether the nitrogen oxide information is above or below a preset value. It may be configured to control the outside air inflow regulator (273).

When the nitrogen oxide information sensed by the nitrogen oxide sensor 261 is equal to or greater than a preset value, the controller 260 may control the outdoor air inflow regulator 273 to reduce the flow rate of the outdoor air flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal when the nitrogen oxide information is equal to or greater than a preset value, the controller 260 controls the outdoor air inflow regulator 273 to reduce the flow rate of outdoor air flowing into the sub-body 212 . can When the nitrogen oxide sensor 261 detects that nitrogen oxide is present, the controller 260 may control the outdoor air inflow regulator 273 to reduce the flow rate of the outdoor air flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal when it is detected that nitrogen oxide is present, the control unit 260 controls the outdoor air inflow regulator 273 so that the flow rate of outdoor air flowing into the sub-body 212 is reduced. can The nitrogen oxide sensor 261 provides a preset signal to the controller 260 when the nitrogen oxide information is less than or equal to a preset value, and is configured not to provide a preset signal to the controller 260 when the nitrogen oxide information is greater than or equal to a preset value. If the preset signal is not provided, the controller 260 may control the outdoor air inflow regulator 273 to reduce the flow rate of the outdoor air flowing into the sub-body 212 .

When the nitrogen oxide information sensed by the nitrogen oxide sensor 261 is equal to or less than a preset value, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal when the nitrogen oxide information is less than or equal to a preset value, the controller 260 controls the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 . can When the nitrogen oxide sensor 261 detects that nitrogen oxide does not exist, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal when it is detected that nitrogen oxide does not exist, the controller 260 controls the outdoor air inflow regulator 273 to increase the flow rate of outdoor air flowing into the sub-body 212 . can do. The nitrogen oxide sensor 261 provides a preset signal to the controller 260 when the nitrogen oxide information is less than or equal to a preset value, and is configured not to provide a preset signal to the controller 260 when the nitrogen oxide information is greater than or equal to a preset value. If the preset signal is not provided, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 .

The control unit 260 may be configured to determine whether the ammonia information is above or below a preset value, and to control the outside air inflow regulator 273 . When the ammonia sensor 263 provides a signal, the controller 260 may be configured to control the outdoor air inflow regulator 273 to increase or decrease the flow rate of outdoor air flowing into the sub-body 212 . When the nitrogen oxide sensor 261 provides a signal, the control unit 260 increases or decreases the flow rate of external air flowing into the sub-body 212 without determining whether the nitrogen oxide information is above or below a preset value. It may be configured to control the outside air inflow regulator (273).

When the ammonia information detected by the ammonia sensor 263 is greater than or equal to a preset value, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when the ammonia information is equal to or greater than a preset value, the control unit 260 may control the outdoor air inflow regulator 273 to increase the flow rate of outdoor air flowing into the sub-body 212 . . When the ammonia sensor 263 detects that ammonia is present, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when it is detected that ammonia is present, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 . . The ammonia sensor 263 provides a preset signal to the controller 260 when the ammonia information is less than or equal to a preset value, and may be configured not to provide a preset signal to the controller 260 when the ammonia information is greater than or equal to a preset value. , when a preset signal is not provided, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 .

When the ammonia information detected by the ammonia sensor 263 is equal to or less than a preset value, the controller 260 may control the outdoor air inflow regulator 273 to reduce the flow rate of the outdoor air flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when the ammonia information is less than or equal to a preset value, the controller 260 may control the outdoor air inflow regulator 273 to reduce the flow rate of outdoor air flowing into the sub-body 212. . When the ammonia sensor 263 detects that ammonia does not exist, the controller 260 may control the outdoor air inflow regulator 273 to reduce the flow rate of the outdoor air flowing into the sub-body 212 . When the ammonia sensor 263 provides a signal when it is detected that ammonia does not exist, the control unit 260 may control the outdoor air inflow regulator 273 so that the flow rate of the outdoor air flowing into the sub-body 212 is reduced. have. The ammonia sensor 263 may be configured not to provide a preset signal to the control unit 260 when the ammonia information is greater than or equal to a preset value, and not to provide a preset signal to the controller 260 when the ammonia information is less than or equal to a preset value. , when the preset signal is not provided, the controller 260 may control the outdoor air inflow regulator 273 to reduce the flow rate of the outdoor air flowing into the sub-body 212 .

The controller 260 may control the outdoor air inflow controller 273 based on the temperature information sensed by the temperature sensor 265 .

The control unit 260 may be configured to determine whether the temperature information is above or below a preset value, and to control the outdoor air inflow controller 273 . When the temperature sensor 265 provides a signal, the controller 260 may be configured to control the outdoor air inflow regulator 273 to increase or decrease the flow rate of the outdoor air flowing into the sub-body 212 . When the temperature sensor 265 provides a signal, the controller 260 introduces outdoor air so that the flow rate of the outdoor air flowing into the sub-body 212 is increased or decreased, without determining whether the temperature information is above or below a preset value. It may be configured to control the regulator 273 .

The control unit 260 may be configured to generate a replacement signal of the reducing agent supply unit 230 when the nitrogen oxide is detected, and the temperature of the reducing agent supply unit 230 is above a certain temperature. The control unit 260 may be configured to generate a replacement signal of the reducing agent supply unit 230 when the nitrogen oxide information is greater than or equal to a preset value, and the temperature of the reducing agent supply unit 230 is above a certain temperature.

The controller 260 may control the outdoor air inflow regulator 273 based on the pressure information sensed by the pressure sensor 267 .

The control unit 260 may be configured to determine whether the pressure information is equal to or greater than a preset value, and to control the outdoor air inflow regulator 273 . When the pressure sensor 267 provides a signal, the control unit 260 may be configured to control the outdoor air inflow regulator 273 to increase or decrease the flow rate of the outdoor air flowing into the sub-body 212 . When the pressure sensor 267 provides a signal, the controller 260 introduces outdoor air to increase or decrease the flow rate of outdoor air flowing into the sub-body 212 without determining whether the pressure information is greater than or less than a preset value. It may be configured to control the regulator 273 .

When the pressure in the main body 211 is greater than or equal to a predetermined pressure, the controller 260 may control the outdoor air inflow regulator 273 to increase the flow rate of the outdoor air flowing into the sub-body 212 . The control unit 260 configured in this way prevents a problem in the nitrogen oxide reduction device 200 such as excessive supply of the gas reducing agent in the main body 211, leakage of the gas reducing agent or the shape of the main body 211 is changed. can be prevented

The controller 260 may control the ratio of the exhaust gas flowing into the sub-body 212 to the outside air by simultaneously controlling the exhaust inflow regulator 271 and the outside air inflow regulator 273 . Through this, the control unit 260 is mixed with the exhaust gas and the outside air inside the sub-body 212, the temperature of the exhaust gas is adjusted, it is possible to efficiently control the amount of heat transferred from the exhaust gas to the reducing agent supply unit (230).

The control unit 260 is a state in which nitrogen oxide is detected, ammonia is not detected, the exhaust inflow controller 271 is adjusted to a preset value or more, and the outdoor air inflow controller 273 is adjusted to a preset value or more. It may be configured to generate a replacement signal of the supply 230 . The control unit 260 is in a state in which nitrogen oxide is detected, ammonia is not detected, the exhaust inflow regulator 271 is adjusted to maximize the inflow of exhaust gas, and the outside air inflow regulator 273 is set to minimize the inflow of outside air. If it is adjusted to be possible, it may be configured to generate a replacement signal of the reducing agent supply unit (230). The control unit 260 configured in this way has the advantage that the user can easily know the replacement time of the reducing agent supply unit (230).

When the control unit 260 detects nitrogen oxide, senses ammonia, adjusts the exhaust inflow controller 271 to a preset value or more, and adjusts the outdoor air inflow controller 273 to a preset value or more, the catalyst filter 250 may be configured to generate a replacement signal. The control unit 260 is in a state in which nitrogen oxide is detected, ammonia is detected, the exhaust inflow regulator 271 is adjusted so that the inflow of exhaust gas is maximized, and the outside air inflow regulator 273 is adjusted so that the inflow of outside air is minimized. If it is in the adjusted state, it may be configured to generate a replacement signal of the catalytic filter 250 . The control unit 260 configured in this way has the advantage that the user can easily know when to replace the catalyst filter 250 .

The operation of the nitrogen oxide reduction device 200 configured in this way is as follows.

First, exhaust gas is introduced into the sub body 212 through the sub exhaust pipe 221 . At this time, outside air may be introduced into the sub-body 212 through the outside air inlet pipe 223 . In this case, the outside air may not flow into the sub-body 212 through the outside air inlet pipe 223 .

The exhaust gas introduced into the sub-body 212 or the exhaust gas mixed with external air meets the reducing agent supply unit 230 and passes through the reducing agent internal flow path 235 . The exhaust gas passes through the reducing agent internal flow path 235 and the heat of the exhaust gas is transferred to the solid reducing agent on the reducing agent supply unit 230 . Ammonia, a gaseous reducing agent, is produced by the heat received from the exhaust gas from the solid reducing agent.

Ammonia and exhaust gas generated in the sub-body 212 are mixed and introduced into the main body 211 through the reducing agent supply pipe 225 . The exhaust gas introduced into the main body 211 (or exhaust gas mixed with ammonia) meets the catalyst filter and passes through the catalyst filter internal flow path 255 . The exhaust gas mixed with ammonia passes through the catalytic filter internal flow path 255, and by the selective catalytic nitrogen oxide reduction method (SCR of NOx), nitrogen oxides are reduced to harmless nitrogen and water vapor, and the exhaust gas is purified. The purified exhaust gas is discharged to the outside of the vehicle 1 through the exhaust discharge pipe 207 .

Since the nitrogen oxide reduction device 200 configured in this way controls to generate an appropriate amount of ammonia, which is a gas reducing agent, there is an advantage in that nitrogen oxides are effectively reduced. In addition, there is an advantage in that ammonia discharged to the outside of the vehicle 1 is reduced.

In addition, the nitrogen oxide reduction device 200 has the advantage of simplifying the configuration and reducing the production cost by allowing the temperature of the reducing agent supply unit 230 to be controlled by the mixing ratio of the exhaust gas and the outside air without a separate temperature control device.

In addition, since the gas reducing agent required to react with the nitrogen oxide is adjusted in an appropriate amount, there is an advantage in that the nitrogen oxide is effectively reduced.

In the above, preferred embodiments of the present invention have been shown and described, but the present invention is not limited to the specific embodiments described above, and in the technical field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims. Various modifications may be made by those of ordinary skill in the art, and these modifications should not be individually understood from the technical spirit or perspective of the present invention.

1: Vehicle 2: Internal combustion engine
100: nitrogen oxide reduction device according to an embodiment
105: exhaust pipe 107: exhaust exhaust pipe
110: body 130: reducing agent supplier
140: temperature controller 150: catalyst filter
160: control unit 161: nitrogen oxide sensor
163: ammonia sensor 165: temperature sensor
167: pressure sensor
200: nitrogen oxide reduction device according to another embodiment
205: exhaust pipe 207: exhaust exhaust pipe
211: main body 212: sub body
221: sub exhaust pipe 223: outside air inlet pipe
225: reducing agent supply pipe 230: reducing agent supply unit
231: solid reducing agent 250: catalyst filter
260: control unit 261: nitrogen oxide sensor
263: ammonia sensor 265: temperature sensor
267: pressure sensor 271: exhaust inlet regulator
273: outside air inflow regulator

Claims (12)

body into which exhaust gas is introduced; and
a reducing agent supply device disposed inside the body and supplying a nitrogen oxide reducing agent; including,
The reducing agent supplier,
A reducing agent internal flow path through which the exhaust gas passes is formed therein,
and a solid reducing agent disposed on the reducing agent internal flow path to receive heat from the exhaust gas to generate a gas reducing agent,
The body is
an auxiliary body in which the reducing agent supply unit is disposed;
a main body connected to the auxiliary body into which the exhaust gas passing through the auxiliary body and the exhaust gas not passing through the auxiliary body are introduced; includes,
an outdoor air inlet pipe having one end connected to the auxiliary body, the other end communicating with the outside, and allowing outside air to flow into the auxiliary body; and
Nitrogen oxide reduction device further comprising an outside air inflow regulator for controlling the outside air flowing into the auxiliary body. The method of claim 1,
The reducing agent supplier,
A nitrogen oxide reduction device configured by coating the solid reducing agent on a frame formed of a heterogeneous material. The method of claim 1,
It is disposed on the rear side of the reducing agent supply inside the body, further comprising a catalyst filter for providing a catalyst for the reaction of nitrogen oxide and the gas reducing agent,
The catalytic filter is
A catalytic filter internal flow path through which the exhaust gas passes is formed therein;
The catalytic filter internal flow path is formed to have a shape corresponding to the reducing agent internal flow path, a nitrogen oxide reduction device. The method of claim 1,
a temperature controller disposed inside the body, in contact with at least a portion of the reducing agent supply unit, and controlling the temperature of the reducing agent supply unit;
a nitrogen oxide sensor for detecting nitrogen oxide information related to nitrogen oxide discharged from the body; and
a controller for controlling the temperature controller based on the nitrogen oxide information sensed by the nitrogen oxide sensor; Including, nitrogen oxide reduction device. 5. The method of claim 4,
Further comprising a gas reducing agent sensor for sensing gas reducing agent information related to the gas reducing agent discharged from the body,
The control unit is
A nitrogen oxide reduction device for controlling the temperature controller based on the gas reducing agent information sensed by the gas reducing agent sensor. 5. The method of claim 4,
The nitrogen oxide information,
is the concentration of nitrogen oxides in the exhaust gas discharged from the body,
The control unit is
When it is determined that the concentration of nitrogen oxides in the exhaust gas discharged from the body is greater than or equal to a preset value, the temperature controller is controlled to increase the temperature of the reducing agent supplier,
Even if the temperature controller is raised more than a preset value, if it is determined that the concentration of nitrogen oxide in the exhaust gas discharged from the body is more than a preset value, generating a replacement signal of the reducing agent supplier, a nitrogen oxide reduction device. delete The method of claim 1,
Arranged in the main body, the nitrogen oxide reduction device further comprising a catalyst filter for providing a catalyst for the reaction of nitrogen oxide and the gas reducing agent. The method of claim 1,
an exhaust inlet regulator for controlling the exhaust gas flowing into the auxiliary body;
a nitrogen oxide sensor for detecting nitrogen oxide information related to nitrogen oxide discharged from the main body; and
a controller for controlling the exhaust inflow regulator based on the nitrogen oxide information sensed by the nitrogen oxide sensor; Further comprising, a nitrogen oxide reduction device. 5. The method of claim 4,
a gas reducing agent sensor for sensing gas reducing agent information related to the gas reducing agent discharged from the main body; further comprising,
The control unit is
A nitrogen oxide reduction device for controlling the outside air inflow regulator based on the gas reducing agent information sensed by the gas reducing agent sensor. 10. The method of claim 9,
The nitrogen oxide information,
is the concentration of nitrogen oxides in the exhaust gas discharged from the main body,
The control unit is
When it is determined that the concentration of nitrogen oxide in the exhaust gas discharged from the main body is greater than or equal to a preset value, the exhaust inflow regulator is controlled to increase the exhaust gas flowing into the auxiliary body,
Even if the exhaust inflow controller is adjusted to a preset value or more, if it is determined that the concentration of nitrogen oxide in the exhaust gas discharged from the main body is more than a preset value, generating a replacement signal of the reducing agent supplier, a nitrogen oxide reduction device . internal combustion engine;
an exhaust pipe through which exhaust gas generated from the internal combustion engine flows;
an exhaust discharge pipe through which the exhaust gas is discharged to the outside;
a body having one side connected to the exhaust pipe and the other side connected to the exhaust discharge pipe; and
a reducing agent supply device disposed inside the body and supplying a nitrogen oxide reducing agent; including,
The reducing agent supplier,
A reducing agent internal flow path through which the exhaust gas passes is formed therein,
and a solid reducing agent disposed on the reducing agent internal flow path to receive heat from the exhaust gas to generate a gas reducing agent,
The body is
an auxiliary body in which the reducing agent supply unit is disposed;
a main body connected to the auxiliary body into which the exhaust gas passing through the auxiliary body and the exhaust gas not passing through the auxiliary body are introduced; includes,
an outdoor air inlet pipe having one end connected to the auxiliary body, the other end communicating with the outside, and allowing outside air to flow into the auxiliary body; and
The vehicle further comprising an outside air inflow regulator for controlling the outside air flowing into the auxiliary body.

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