KR20200078016A - A Reactor for A System for Purification of NOx Emissions and A System for Purification of NOx Emissions - Google Patents

Abstract

The present invention relates to a technique for reducing a nitrogen oxide (NOx) which is harmful discharge gas discharged from an internal combustion engine or a combustor. According to one embodiment, a reactor for being used in a nitrogen oxide purifying system includes: a main body; at least one gas outlet formed on the main body; at least one heat transfer body protruding toward an inner space of the main body; and a cooling member and a heating member installed in each heat transfer body along a shape of the heat transfer bodies, wherein the heat transfer bodies are installed below the gas outlets in a gravity direction and formed to protrude from a lower portion of the main body in an upper direction in a gravity applying direction.

Description

Reactor for nitrogen oxide purification system and nitrogen oxide purification system

The technology disclosed herein relates to a technique for reducing nitrogen oxide (NOx), which is a harmful emission gas emitted from an internal combustion engine or a combustor, and more specifically, thermally decomposes solid ammonium salt to make ammonia and react with nitrogen oxide on an SCR catalyst. It relates to a nitrogen oxide purification system and a reactor used in a nitrogen oxide purification system capable of purifying nitrogen harmless to the human body.

In general, as a technology for reducing nitrogen oxides emitted from internal combustion engines, especially diesel engines, nitrogen is reacted on the catalyst by using ammonia, urea or hydrocarbons, which are reducing agents or reducing agents by exhaust gas recirculation (EGR). And selective catalytic reduction (SCR) to reduce oxygen and oxygen are used.

When using hydrocarbons such as diesel among the selective reduction catalyst technology, there is an advantage in that an auxiliary reducing agent supply device is not required because the fuel of an internal combustion engine or a combustor is used as a reducing agent, but when oxygen is present in the exhaust gas, the hydrocarbon reacts first with oxygen. Therefore, there is a disadvantage in that the reduction performance of nitrogen oxide is low.

As for the selective reduction catalyst technology using liquid urea, which is another selective reduction catalyst technology, when a liquid urea made by dissolving urea, a substance existing in a solid state at room temperature in water, is injected into an automobile exhaust pipe, it is thermally decomposed at a temperature of about 150°C or higher. It is converted into ammonia, and the ammonia produced in this way reduces nitrogen oxides to harmless nitrogen with the help of a selective reduction catalyst such as vanadium pentoxide (V2O5) or geolite. The selective reduction catalyst technology using the liquid urea has an advantage of having a wide catalytic reaction temperature range and excellent durability, and can obtain high nitrogen oxide purification efficiency of about 60 to 80%.

However, the selective reduction catalyst technology for liquid urea requires a large-scale social infrastructure to supply liquid urea, and additional devices such as containers and sprayers for storing liquid urea, and the freezing point of liquid urea is -11℃. There is a disadvantage in that the entire system is complicated because separate insulation measures are necessary to maintain the temperature of the system such as the container and the spraying device at a temperature above the proper temperature. In addition, in order to lower the freezing point of the liquid urea, water is mixed with the liquid urea more than 60%, so the storage container has a drawback.

In order to compensate for the shortcomings of the liquid urea, a technology using solid urea (Korean Patent Registration No. 10-0924591, 10-0999574, etc.) has been proposed, but the solid urea has a high thermal decomposition temperature of about 140 ℃, so it has a lot of electrical energy or exhaust heat energy. There is a disadvantage in that urea is solidified in the pipeline and the like, if it is not necessary to maintain the thermal decomposition temperature in the reactor and the pipeline.

In addition, although a technique using a solid ammonium salt having a low thermal decomposition temperature has been applied, the reactor in which the solid ammonium salt is stored is entirely heated by using a heat exchanger using exhaust heat or cooling water from a heater or a vehicle to thermally decompose the solid ammonium salt to ammonia. There is a disadvantage that a large amount of energy is required for pyrolysis.

The technology disclosed in this specification aims to provide an improved nitrogen oxide purification system, and a technical problem to be achieved by the nitrogen oxide purification system according to the technical idea of the technology disclosed herein is a problem for solving the problems mentioned above. It is not limited to, another task that is not mentioned will be clearly understood by those skilled in the art from the following description.

Reactor for use in a nitrogen oxide purification system according to an embodiment of the technology disclosed herein, the main body; At least one gas outlet formed in the body; At least one heat transfer body protruding toward the interior space of the body; It includes a cooling member and a heating member installed inside each heat transfer body along the shape of the heat transfer body, and the heat transfer body is installed below the gas outlet in the direction of gravity, and from the bottom of the body in the direction of gravity action. It is formed to protrude upward.

The heat transfer body is configured in a fin shape.

The reactor is characterized in that it is a main or auxiliary reactor configured to produce gaseous ammonia from solid ammonium.

A nitrogen oxide purification system according to another embodiment of the technology disclosed herein, is configured to produce ammonia in the gaseous phase from solid ammonium and comprises the main reactor described above; An ammonia gas transfer pipe connected to the main reactor and configured to transfer the generated ammonia to an exhaust pipe; A pressure regulator installed on the ammonia gas transfer pipe and controlling a flow pressure of the ammonia generated; And a gas injector installed in the ammonia gas transfer pipe and connected to the pressure regulator.

An additional gas movement path in gas communication with the main reactor and disposed in parallel with the ammonia gas transfer pipe, wherein the additional gas movement path, when starting the engine, the delay time from the main reactor to the generation of ammonia It further comprises an auxiliary reactor configured to produce ammonia during.

The additional gas movement path: is connected to the main reactor, installed in the gas inlet pipe, when the engine starts, an auxiliary reactor for generating ammonia for a delay time from the main reactor to ammonia is produced; A main reactor pressure regulator connected to the main reactor, installed in a gas inlet pipe, and controlling a flow pressure of the ammonia generated; An opening/closing valve installed in the gas inlet pipe to control the amount of ammonia generated; An auxiliary reactor pressure regulator connected to the auxiliary reactor, installed in a gas delivery pipe, and controlling the flow pressure of the ammonia generated; And an auxiliary reactor gas injector connected to the auxiliary reactor pressure regulator and installed in a gas delivery pipe.

A nitrogen oxide purification system according to another embodiment of the technology disclosed herein is a nitrogen oxide purification system for injecting ammonia gas into an exhaust pipe through a first path and a second path from a main reactor that produces ammonia from solid ammonium, The first path includes: a main reactor pressure regulator connected to the main reactor, installed in the ammonia gas transfer pipe, and controlling the flow pressure of the generated ammonia; It is connected to the main reactor pressure regulator, and includes a main reactor gas injector installed in the ammonia gas transfer pipe, and the second path is: connected to the main reactor, installed in the gas inlet pipe, and when the engine starts, An auxiliary reactor for producing ammonia for a delay time from the reactor to the production of ammonia; A main reactor pressure regulator connected to the main reactor, installed in a gas inlet pipe, and controlling a flow pressure of the ammonia generated; An opening/closing valve installed in the gas inlet pipe to control the amount of ammonia generated; An auxiliary reactor pressure regulator connected to the auxiliary reactor, installed in a gas delivery pipe, and controlling the flow pressure of the ammonia generated; And an auxiliary reactor gas injector connected to the auxiliary reactor pressure regulator and installed in a gas delivery pipe, wherein at least one of the main reactor and the auxiliary reactor is a previously described reactor.

Nitrogen oxide purification system according to another embodiment of the technology disclosed in the present disclosure, a first transport path for transporting ammonia gas generated by the main reactor containing solid ammonium to the exhaust pipe-the first transport path, the main reactor And a gas injector connected to the main reactor pressure regulator for controlling the flow pressure of the ammonia, and an ammonia gas transfer pipe connected to the main reactor pressure regulator; And the main reactor pressure regulator of the first transfer path and the gas injector in common, but between the common components is a second transfer path distinct from the first transfer path-the second transfer path, the A main reactor pressure regulator, an on-off valve connected to the main reactor pressure regulator and installed in a gas inlet pipe, an auxiliary reactor connected to the on-off valve and installed in a gas inlet pipe, an auxiliary connected to the auxiliary reactor and installed in a gas delivery pipe And a reactor pressure regulator, and the gas injector installed in the gas delivery pipe, wherein at least one of the main reactor and the auxiliary reactor is a previously described reactor.

The main reactor pressure regulator is installed upstream from the main reactor gas injector, and the auxiliary reactor pressure regulator is installed upstream from the auxiliary reactor gas injector.

In operation, the inlet temperature of the main reactor pressure regulator is controlled to be higher than the internal temperature of the main reactor, and the inlet temperature of the auxiliary reactor pressure regulator is controlled to be higher than the internal temperature of the auxiliary reactor.

In operation, the downstream temperature of the main reactor pressure regulator is controlled to be lower than the upstream temperature, and the downstream temperature of the auxiliary reactor pressure regulator is controlled to be lower than the upstream temperature.

When the engine is started, ammonia is supplied from the auxiliary reactor, and when the main reactor is heated, ammonia is supplied from the main reactor and at the same time, the auxiliary reactor is controlled to charge.

After the operation is completed, the main reactor and the auxiliary reactor are opened to prevent pressure increase in the main reactor.

According to the nitrogen oxide purification system according to an embodiment of the technology disclosed in the present disclosure, the ammonia is rapidly decomposed by rapidly thermally decomposing the stacked solid ammonium by controlling the stacking position of the solid ammonium by a cooling module when the operation is stopped. Supply is possible.

However, the effects that can be achieved by the nitrogen oxide purification system according to an embodiment of the technology disclosed herein are not limited to those mentioned above, and other effects not mentioned are apparent to those skilled in the art from the following description. Can be understood.

Brief descriptions of each drawing are provided in order to better understand the drawings cited herein.
1 shows an embodiment of the technology disclosed herein.
2 shows another embodiment of the technology disclosed herein.
3 shows another embodiment of the technology disclosed herein.
4 is a graph showing the pyrolysis pressure-temperature plot of solid ammonium in relation to temperature control of the technology disclosed herein.
5 shows an embodiment of a main reactor that can be applied to the nitrogen oxide purification system of the technology disclosed herein.
6 shows an embodiment of an auxiliary reactor that can be applied to the nitrogen oxide purification system of the technology disclosed herein.

The technology disclosed in the present specification may be modified in various ways and may have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail through detailed description. However, this is not intended to limit the technology disclosed herein to specific embodiments, and it is understood that the technology disclosed herein includes all modifications, equivalents, or substitutes included in the spirit and technical scope of the technology disclosed herein. Should be.

In describing the technology disclosed in the present specification, when it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the technology disclosed herein, the detailed description will be omitted. In addition, the numbers (for example, first, second, etc.) used in the description process of the present specification are only identification numbers for distinguishing one component from other components.

Also, in this specification, when one component is referred to as "connected" or "coupled" with another component, the one component may be directly connected or combined with the other component, but is specifically opposed to It should be understood that as long as the substrate does not exist, it may be connected or combined through another element in the middle.

In addition, in the present specification, two or more components may be combined into one component, or one component may be divided into two or more for each subdivided function. In addition, each of the components to be described below may additionally perform some or all of the functions of other components in addition to the main functions of the components, and some of the main functions of the components are different. Needless to say, it may also be carried out exclusively by components.

Expressions such as “first”, “second”, “first”, or “second” used in various embodiments may modify various components, regardless of order and/or importance, and the corresponding components It is not limited. For example, the first component may be referred to as a second component without departing from the scope of the technology disclosed herein, and similarly, the second component may also be referred to as a first component.

Hereinafter, a nitrogen oxide purification system according to a preferred embodiment will be described in detail.

Example 1

Referring to FIG. 1, a nitrogen oxide purification system according to an embodiment includes a main reactor 100 for generating ammonia in a gas phase from solid ammonium; An ammonia gas transfer pipe 140 connected to the main reactor 100 and configured to transfer the generated ammonia to an exhaust pipe; It is installed on the ammonia gas transfer pipe 140, a pressure regulator 110 for controlling the flow pressure of the generated ammonia; And a gas injector 130 installed in the ammonia gas transfer pipe 140 and connected to the pressure regulator 110.

Specifically, the ammonia gas generated from solid ammonium in the main reactor 100 may be connected to be supplied to the exhaust pipe 20 of the engine where the SCR catalyst 30 is installed, as shown in FIG. 1, and the ammonia gas to the exhaust pipe 20 A pressure regulator 110 and a gas injector 130 are installed in the supplied ammonia gas transfer pipe 140 so that the pressure and flow rate of the ammonia gas injected into the exhaust pipe 20 can be adjusted. The pressure regulator 110 is configured to control the flow rate of the ammonia gas supplied so that the ammonia gas of constant pressure is supplied to the exhaust pipe. In addition, an injection nozzle is installed in the exhaust pipe 20 to uniformly inject ammonia gas into the exhaust pipe, and an SCR catalyst 30 is provided at the rear end of the exhaust pipe in which the injection nozzle is installed to mix ammonia gas and exhaust gas, and The purification reaction in the catalyst 30 causes nitrogen oxide (NOx), which is a harmful substance in the exhaust gas, to be reduced to nitrogen harmless to the human body to reduce the exhaust gas.

In the present embodiment, solid ammonium decomposes into ammonia gas by heat and cools to solidify again to solid ammonium, and ammonium carbamate (NH2COONH4), ammonium carbonate (NH4)2CO3) , Ammonium bicarbonate (NH4HCO3) or urea (NH2CONH2) and the like may be included, preferably ammonium carbamate (NH2COONH4).

At this time, the reaction formula in which ammonium carbamate is thermally decomposed to produce ammonia is as follows.

NH2COONH4 ↔ 2NH3 +CO

And when the generated ammonia is injected into the exhaust pipe, a representative reaction formula in which NOx is purified on a selective reduction (SCR) catalyst 30 is as follows.

NO + NO2 + 2NH3 → 2N2+3H2O

In this embodiment, the main reactor 100 is provided with solid ammonium (S) therein, so that ammonia gas can be generated from the solid ammonium. The resulting ammonia is discharged through the gas outlet 102.

As illustrated in FIG. 5, a cooling member 101b and a heating member 101a may be installed inside the main reactor 100 inside the heat transfer body 101. In the heat transfer body 101 in the present embodiment, a cooling member 101b and a heating member 101a are formed inside the main reactor 100 to form a protruding volume toward the interior space and along the shape of the protruding volume. It means the structure formed. Here, the number of protruding heat transfer bodies 101 is irrespective, but the larger the contact surface area, such as a (plural) fin shape, is preferred to increase the heat transfer efficiency with solid ammonium (S). In particular, in relation to the protruding direction/position, it is necessary to form a body to protrude from the bottom of the reactor in the direction of gravitational action where solid ammonium is most frequently located during operation stoppage for fast heat transfer at startup. The heat transfer body 101 is installed below the gas outlet 102 in the direction of gravity to maximize the solidification effect. The arrangement of the cooling member 101b and the heating member 101a inside the heat transfer body changes to solid ammonium by reacting ammonia/carbon dioxide gas at the lowest temperature when the operation is stopped, and solid ammonium when the engine starts. It is based on the technical idea that it is possible to start the purification system quickly with less energy by intensively supplying and gasifying a heat source where it is located, and maximizing the solidification effect when positioned in the lower part in the direction of gravity.

As an example of the cooling member 101b that can be used in this embodiment, there may be air or cooling water. Further, examples of the heating member 101a that can be used in this embodiment include electric heaters, heated air, and heated water.

The pressure regulator 110 and the injector 130 are installed in the ammonia gas transfer pipe 140 of the present embodiment, and the pressure regulator 110 is configured to be located upstream of the gas injector 130. The pressure regulator 110 is configured to control the flow pressure of ammonia generated in the main reactor 100. Since a general dosing module configuration consisting of a pressure regulator and an injector, a pressure sensor, a temperature sensor, and a heater is applied in this embodiment, detailed description is omitted.

The nitrogen oxide purification system according to the present embodiment, as shown in FIG. 4, is capable of maintaining the temperature above the pyrolysis temperature at a given pressure according to the pyrolysis pressure-temperature diagram of solid ammonium, whereby ammonia is used as solid ammonium. As a result, it is possible to prevent solidification in the conveying pipeline.

Specifically, the pressure regulator 110 is installed upstream from the gas injector 130, and the pressure and flow rate of ammonia generated in the main reactor 100 are constant, for example, 2 to 3 bar through the pressure regulator 110. It is possible to maintain and accurately control through the gas injector 130. In particular, in relation to the control to maintain the temperature above the pyrolysis temperature at a given pressure according to the pyrolysis pressure-temperature diagram of solid ammonium described above, the inlet temperature 102 of the pressure regulator 110 attached to the main reactor during operation It is possible to prevent the clogging clogging phenomenon of the pressure regulator 110 by controlling to be higher than the internal temperature 101 of the main reactor 100. Since the pressure regulator upstream has a high pressure, it is effective to maintain a higher temperature than the main reactor 100 to prevent solidification of the pressure regulator 110, and the pressure in the downstream of the pressure regulator is low, so even if the temperature is partially lowered, the gas injector 130 ) Does not cause clogging problems. As described above, in the present embodiment, the temperature of the dosing module including the pressure regulator is controlled by using the temperature inside the reactor as a control input variable, which is distinguished from the prior art method using pressure as the control input variable in the temperature control method. .

Hereinafter, an operation method of the exhaust gas purification system according to the embodiment including the above-described configuration will be described.

First, when the user starts the vehicle to drive the vehicle, the heating means of the ammonia dosing module including the main reactor 100 and/or the pressure regulator 110 are operated at the same time as the engine starts. At this time, among the heating means, the heating means using the electric heater as a heat source is operated at the same time as the engine starts, and the heating means using the exhaust gas or cooling water as a heat source has a predetermined time difference from the heating means using the electric heater as a heat source. Can be activated. This is because exhaust gas and coolant do not have sufficient thermal energy at the beginning of the engine. In addition, when the exhaust gas or the cooling water has sufficient heat energy, the heating means using the electric heater as a heat source and the heating means using the exhaust gas or cooling water as a heat source may be operated together. On the other hand, when the heating of the main reactor 100 or the dosing module is excessively performed, operation of heating means using an electric heater as a heat source is stopped, and only heating means using exhaust gas or cooling water as a heat source can be operated.

On the other hand, when the main reactor 100 is heated to solid ammonium by heating means to produce ammonia, the internal pressure of the main reactor 100 is increased by the generated ammonia. Then, when the internal pressure of the main reactor 100 reaches a predetermined level, the ammonia flows out of the main reactor 100 through the gas outlet 102 and flows to the dosing module.

The ammonia introduced into the dosing module flows to the injection nozzle side at a constant pressure and quantity by a pressure regulator 110 and a gas injector 130, and the ammonia flowed to the injection nozzle is a SCR catalyst inside the exhaust pipe 20 at a constant pressure and quantity It is injected to the (30) side and mixed with the exhaust gas. Here, in order to prevent clogging of the pressure regulator 110, the inlet temperature 102 of the pressure regulator 110 attached to the main reactor during operation is controlled to be higher than the internal temperature 101 of the main reactor 100. .

The exhaust gas in which the ammonia is mixed is purged of nitrogen oxides by the SCR catalyst 30 and discharged into the atmosphere.

Example 2

Referring to FIG. 2, a nitrogen oxide purification system according to another embodiment will be described, but a duplicate description of a corresponding configuration in the previous embodiment will be omitted. In the nitrogen oxide purification system in this embodiment, a separate auxiliary reactor is added in addition to the main reactor of the preceding Example 1, and a second transport pipe for transporting ammonia gas generated from the auxiliary reactor is added in parallel. Includes the configuration to be installed.

Specifically, since the purification system according to the embodiment basically includes the ammonia gas supply unit according to the configuration of Example 1, the main reactor 100 for generating gaseous ammonia from solid ammonium; An ammonia gas transfer pipe 140 connected to the main reactor 100 and configured to transfer the generated ammonia to an exhaust pipe; It is installed on the ammonia gas transfer pipe 140, a pressure regulator 110 for controlling the flow pressure of the generated ammonia; And a gas injector 130 installed in the ammonia gas transfer pipe 140 and connected to the pressure regulator 110.

In addition, the purification system further includes an auxiliary reactor 200 in gas communication with the main reactor 100. The auxiliary reactor 200 is installed in the gas inlet pipe 240 communicating with the main reactor, and is configured to generate ammonia for a delay time from the main reactor 100 to the generation of ammonia when the engine starts. On the gas inlet pipe 240 between the main reactor 100 and the auxiliary reactor 200, an on-off valve 121 is installed, and the discharge amount of ammonia gas generated from the main reactor 100 according to the operating situation is installed by these valves. Adjustments or gas flow changes can be made.

A main reactor pressure regulator 111 that is connected to the main reactor 100 and controls the flow pressure of the ammonia generated may be installed in the gas inlet pipe 240.

The gas delivery pipe 250 is installed on the downstream side of the auxiliary reactor 200, and the auxiliary reactor pressure regulator 210 is installed to control the flow pressure of the ammonia gas. The auxiliary reactor pressure regulator 210 is configured to be connected to the auxiliary reactor gas injector 230 installed in the downstream gas delivery pipe 250.

According to the system of the present embodiment, a main reactor pressure regulator 111 and an on-off valve 121 may be installed in the gas inlet pipe 240, and since they are connected to the auxiliary reactor 200, the main reactor pressure regulator 111 ) Can control the flow pressure of ammonia gas from the main reactor, and the on-off valve 121 can control the discharge amount of ammonia. And, since the gas delivery pipe 250 is connected to the auxiliary reactor 200, the auxiliary reactor pressure regulator 210 and the auxiliary reactor gas injector 230 may be installed, the auxiliary reactor pressure regulator 210 is the auxiliary reactor It is installed upstream of the gas injector 230 to control the flow pressure of ammonia. As described in Example 1, by controlling the inlet temperature of the auxiliary reactor pressure regulator 210 attached to the auxiliary reactor during operation to be higher than the internal temperature of the auxiliary reactor 200, clogging of the pressure regulator 210 for the auxiliary reactor is blocked. The phenomenon can be prevented. Since the pressure upstream of the auxiliary reactor pressure regulator is high, a higher temperature is required downstream of the pressure regulator to prevent effective coagulation, and the pressure of the auxiliary reactor pressure regulator downstream is low, so no problem of clotting clogging occurs even if the temperature is partially lowered.

According to the present embodiment, when the engine is started, ammonia is supplied from the auxiliary reactor 200, and when the main reactor 100 is heated, ammonia is supplied from the main reactor and at the same time, the auxiliary reactor 200 is charged. Can. That is, at start-up, the reducing agent is supplied from the auxiliary reactor 200 that can be quickly heated, and when the main reactor 100 is heated over time, the reducing agent is supplied from the main reactor 100 and the auxiliary reactor “at the same time” for a certain time. 200 corresponds to a filling system. Even in the prior art, although an example of using an auxiliary reactor is found, there is no concept of filling the auxiliary reactor of the present embodiment described above, and at least this embodiment is a technique of filling the auxiliary reactor while supplying ammonia to the exhaust pipe as the main reactor. It is characterized by the idea, and the system convenience is improved because the user does not need to separately fill the auxiliary reactor.

In addition, this embodiment corresponds to a system that prevents pressure increase of the main reactor by opening the main reactor 100 and the auxiliary reactor 200 after the operation is finished. When the operation is finished, the pressure of the reactor increases because the ammonia gas is not injected into the exhaust pipe. At this time, by opening the main reactor and the auxiliary reactor, the pressure of the main reactor is prevented from rising, thereby preventing the reactor from being exposed to high pressure. have.

On the other hand, in this embodiment, a gas inlet pipe 240 and one gas outlet pipe 250 are installed on both sides of the auxiliary reactor, but a plurality of gas inlet pipes and/or gas outlet pipes are configured as necessary. It will be appreciated.

In addition, the configuration of the heat transfer body 101 of the main reactor 100 according to the first embodiment can be applied as it is to the auxiliary reactor 200 of the same embodiment. That is, as illustrated in FIG. 6, the auxiliary reactor 200 includes at least one heat transfer body 201 forming a volume protruding into the main reactor, and a cooling member along the shape of the volume protruding therein 201b and a heating member 201a may be installed. In order to increase the heat transfer efficiency with solid ammonium, it is more preferable that the heat transfer body 201 has a larger contact surface area, such as a fin shape, and a plurality of such fins are formed. It can be installed at the bottom in the direction to maximize the solidification effect.

Example 3

Example 3 corresponds to a modified example that performs the same function as in Example 2. That is, in the second embodiment, each of the main reactor pressure regulators 110 and 121 from the main reactor is replaced with one common pressure regulator, and the main reactor gas injector 130 and the auxiliary reactor gas injector 230 are one common gas. It consists of a method of integrating the starting gas transport path from the main reactor and the final reducing agent injection path to the exhaust pipe by replacing with an injector.

More specifically, referring to Figure 3, the nitrogen oxide purification system according to the embodiment is largely "main reactor (100)? Main reactor common pressure regulator 110-1st transfer path (upper path in FIG. 3) / 2nd transfer path (lower path in FIG. 3)? Common gas injector 130? Exhaust pipe”.

The first transfer path is a path for transferring the ammonia gas generated by the main reactor 100 containing solid ammonium to the exhaust pipe 20. The first transport path is connected to the main reactor 100, the main reactor common pressure regulator 110 for controlling the flow pressure of the generated ammonia, and the ammonia gas connected to the main reactor common pressure regulator 110 It comprises a common gas injector 130 that is connected via a transfer pipe 140.

The second transfer path, the main reactor common pressure regulator 110 and the common gas injector 130 of the first transfer path are commonly included, but between the common components are distinguished from the first transfer path It is a path. The second transfer path is connected to the main reactor common pressure regulator 110, the main reactor common pressure regulator 110 and is connected to the on/off valve 121 and the on/off valve 121 installed in the gas inlet pipe. The secondary reactor 200 installed in the gas inlet pipe, the secondary reactor pressure regulator 210 connected to the secondary reactor 200 and installed in the gas delivery pipe, and the common gas injector 130 installed in the gas delivery pipe ).

According to the embodiment of the present invention as described above, the flow rate and temperature of ammonia generated in the main reactor 100 may be controlled to be injected into the exhaust pipe 20. In addition, the injected ammonia is mixed with nitrogen oxide (NOx), which is a harmful emission gas discharged from an internal combustion engine or a combustor, to cause a purification reaction in the SCR catalyst 30, and the nitrogen oxide contained in the exhaust gas is reduced to nitrogen harmless to the human body.

As already described in Examples 1 and 2, in relation to pressure-temperature control, the reactor internal temperature is also used as a control input variable to prevent the problem of solidification inside the flow tube of the dosing module.

And, as in the second embodiment, when starting, the auxiliary reactor 200 that can be heated quickly is supplied with a reducing agent, and when the main reactor 100 is heated over time, the main reactor 100 supplies the reducing agent. Since the auxiliary reactor 200 “at the same time” corresponds to a system for filling, the system convenience is improved because the auxiliary reactor does not need to be separately filled by the user.

The present invention has been described in detail above, but the scope of the present invention is not limited thereto, and it is common in the art that various modifications and variations are possible without departing from the technical spirit of the present invention as set forth in the claims. It will be obvious to those who have the knowledge of

Claims (15)

A reactor for use in nitrogen oxide purification systems,
main body;
At least one gas outlet formed in the body;
At least one heat transfer body protruding toward the interior space of the body;
A cooling member and a heating member installed inside each heat transfer body along the shape of the heat transfer body,
The heat transfer body is installed in the lower portion in the direction of gravity than the gas outlet, the reactor is formed to protrude upward from the lower portion of the body in the direction of gravity action.
According to claim 1,
The heat transfer body is a reactor composed of a fin (fin) shape.
According to claim 1,
The reactor is a reactor, characterized in that the main or auxiliary reactor is configured to produce ammonia in the gas phase from solid ammonium.
As a nitrogen oxide purification system,
A main reactor according to claim 1, configured to produce gaseous ammonia from solid ammonium;
An ammonia gas transfer pipe connected to the main reactor and configured to transfer the generated ammonia to an exhaust pipe;
A pressure regulator installed on the ammonia gas transfer pipe and controlling a flow pressure of the ammonia generated; And
A nitrogen oxide purification system including a gas injector installed in the ammonia gas transfer pipe and connected to the pressure regulator.
The method of claim 4,
The pressure regulator is installed upstream of the gas injector, the nitrogen oxide purification system characterized in that the inlet temperature of the pressure regulator is controlled to be higher than the internal temperature of the main reactor during operation.
The method of claim 4,
Nitrogen oxide purification system, characterized in that during operation, the downstream temperature of the pressure regulator is controlled to be lower than the upstream temperature.
The method of claim 4,
An additional gas movement path in gas communication with the main reactor and disposed in parallel with the ammonia gas transfer pipe, wherein the additional gas movement path, when starting the engine, the delay time from the main reactor to the generation of ammonia A nitrogen oxide purification system further comprising an auxiliary reactor configured to produce ammonia during.
The method of claim 7,
The additional gas movement path:
An auxiliary reactor connected to the main reactor, installed in a gas inlet pipe, and generating ammonia during a delay time from the main reactor to ammonia when the engine starts;
A main reactor pressure regulator connected to the main reactor, installed in a gas inlet pipe, and controlling a flow pressure of the ammonia generated;
An opening/closing valve installed in the gas inlet pipe to control the amount of ammonia produced;
An auxiliary reactor pressure regulator connected to the auxiliary reactor, installed in a gas delivery pipe, and controlling the flow pressure of the ammonia generated; And
A nitrogen oxide purification system comprising an auxiliary reactor gas injector connected to the auxiliary reactor pressure regulator and installed in a gas delivery pipe.
A nitrogen oxide purification system for injecting ammonia gas into an exhaust pipe through a first path and a second path from a main reactor that produces ammonia from solid ammonium,
The first route is:
A main reactor pressure regulator connected to the main reactor, installed in the ammonia gas transfer pipe, and controlling the flow pressure of the generated ammonia;
It is connected to the main reactor pressure regulator, and includes a main reactor gas injector installed in the ammonia gas transfer pipe,
The second route is:
An auxiliary reactor connected to the main reactor, installed in a gas inlet pipe, and generating ammonia during a delay time from the main reactor to ammonia when the engine starts;
A main reactor pressure regulator connected to the main reactor, installed in a gas inlet pipe, and controlling a flow pressure of the ammonia generated;
An opening/closing valve installed in the gas inlet pipe to control the amount of ammonia produced;
An auxiliary reactor pressure regulator connected to the auxiliary reactor, installed in a gas delivery pipe, and controlling the flow pressure of the ammonia generated; And
It is connected to the auxiliary reactor pressure regulator, and includes an auxiliary reactor gas injector installed in the gas delivery pipe,
At least one of the main reactor and the auxiliary reactor is a nitrogen oxide purification system, characterized in that the reactor according to claim 1.
A first transport path for transporting the ammonia gas generated by the main reactor containing solid ammonium to the exhaust pipe-the first transport path is connected to the main reactor, the main reactor pressure for controlling the flow pressure of the ammonia generated And a gas injector connected via an ammonia gas transfer pipe connected to the regulator and the main reactor pressure regulator; And
The main reactor pressure regulator of the first transport path and the gas injector are commonly included, but a second transport path different from the first transport path between the common components-the second transport path is the main Reactor pressure regulator, an on-off valve connected to the main reactor pressure regulator and installed on the gas inlet pipe, an auxiliary reactor connected to the on-off valve and installed on the gas inlet pipe, an auxiliary reactor connected to the auxiliary reactor and installed on the gas delivery pipe Includes a pressure regulator and the gas injector installed in the gas delivery pipe-
Including,
At least one of the main reactor and the auxiliary reactor is a nitrogen oxide purification system, characterized in that the reactor according to claim 1.
The method of claim 9 or 10,
The main reactor pressure regulator is installed upstream than the main reactor gas injector, and the auxiliary reactor pressure regulator is installed upstream of the auxiliary reactor gas injector.
The method of claim 11,
During operation, the inlet temperature of the main reactor pressure regulator is controlled to be higher than the internal temperature of the main reactor, and the inlet temperature of the secondary reactor pressure regulator is controlled to be higher than the internal temperature of the auxiliary reactor. Purification system.
The method of claim 11,
Nitrogen oxide purification system characterized in that during operation, the downstream temperature of the main reactor pressure regulator is controlled to be lower than the upstream temperature, and the downstream temperature of the auxiliary reactor pressure regulator is controlled to be lower than the upstream temperature.
The method of claim 9 or 10,
Nitrogen oxide purification system, characterized in that when the engine is started, ammonia is supplied from the auxiliary reactor, and when the main reactor is heated, ammonia is supplied from the main reactor and the auxiliary reactor is charged for a certain period of time.
The method of claim 9 or 10,
Nitrogen oxide purification system, characterized in that to prevent the pressure rise of the main reactor by opening the main reactor and the auxiliary reactor after the operation is finished.

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