KR101717603B1 - MIXER OF SCR APPARATUS FOR REDUCING NOx EMISSIONS - Google Patents

Abstract

The present invention relates to purification of an exhaust gas. More specifically, the present invention relates to a mixer apparatus for SCR capable of maximizing performance of nitrogen oxide removal in an SCR apparatus by increasing mixing properties of a reducing agent. The mixer apparatus for SCR comprises: a casing unit (1100) including an adapter unit arranged on a front end portion of the SCR apparatus in an exhaust line and joined to an injector and a body; and a mixing unit (1200) including an outer pipe arranged on an inner circumferential side of the body, an inner pipe arranged on the inner circumferential side of the outer pipe, a first blade unit arranged between the outer pipe and the body, and a second blade unit arranged between the inner pipe and the outer pipe. The second blade unit generates rotation flow in a direction opposite to the first blade unit.

Description

TECHNICAL FIELD [0001] The present invention relates to a mixer apparatus for SCR for reducing nitrogen oxides (MIXER OF SCR APPARATUS FOR REDUCING NOx EMISSIONS)

The present invention relates to purification of exhaust gas, and more particularly, to a mixer apparatus for SCR capable of maximizing nitrogen oxide removal performance in an SCR apparatus by increasing the mixing property of a reducing agent.

In general, diesel engines are used in various industries such as automobiles, ships, and general industrial industries with low fuel consumption and excellent reliability, and demand is continuously increasing due to high output and high load operation.

However, in developed countries, such diesel vehicles are considered to be the main cause of air pollution, accounting for 40% of total air pollution.

In order to cope with this, each country is strengthening the exhaust gas regulation of diesel engines. Air pollution of such diesel cars is mainly caused by NOx and particulate matter (PM).

The main targets of diesel automobile emission regulation are nitrogen oxide and particulate matter. The countermeasures include delay of fuel injection, reduction of nitrogen oxide concentration by Exhaust Gas Recirculation (EGR), reduction of particulate matter And to improve the combustion performance of the engine.

(Diesel Particulate matter Filter), SCR (Selective Catalyst Reduction), and the like to reduce diesel particulate matter (PM) and nitrogen oxide (NOx), which are pollutants contained in exhaust gas of an engine, And the same exhaust gas post-treatment device.

At this time, the DOC functions to oxidize total hydrocarbons and carbon monoxide in the exhaust gas, oxidize nitrogen monoxide to nitrogen dioxide, and DPF allows the particulate matter to be purified through a chemical conversion process.

In the SCR, the reducing agent injected in the flow direction of the exhaust gas through the injector is hydrolyzed into ammonia (NH ₃ ) by the heat of the exhaust gas, and the nitrogen oxide is converted into nitrogen gas (N ₂ ) And water (H ₂ O).

On the other hand, an exhaust gas post-treatment apparatus employing DOC, DPF and SCR is provided with a mixing module having an injector for injecting a reducing agent between the DPF and the SCR.

Ammonia, urea and hydrocarbons are usually used as the reducing agent.

In this mixing module, the injection pressure of the reducing agent through the injector is increased according to the EM (Emission) standard strengthening to increase the injection speed of the reducing agent according to the increase of the injection pressure.

Korean Patent Laid-Open No. 10-2016-0109981 discloses a prior art SCR system, and Fig. 1 is a configuration diagram thereof.

The SCR reactor 110 is installed on the exhaust line 100 and passes the exhaust gas flowing through the exhaust line 100 to a catalyst layer disposed therein to remove harmful components in the exhaust gas. Is installed on the line 100 for uniformly mixing the exhaust gas in the exhaust line 100 with the reducing agent and is disposed downstream of the injection nozzle 130 at a position spaced from the injection nozzle 130 by a predetermined distance, The reducing agent injected by the injection nozzle 130 is mixed with the exhaust gas at a uniform concentration.

The static mixer 120 described above generates a swirl in the exhaust gas in the exhaust line 100 downstream of the injection nozzle 130 to generate a reducing agent (for example, a urea droplet) injected by the injection nozzle 130 Promotes heat transfer and mixing between the exhaust gases passing through the exhaust line 100 so that the reducing agent can be mixed with the exhaust gas at a uniform concentration.

However, in recent years, the injection pressure and back pressure for dosing are increasing. As a simple impeller-type mixer, it is practically impossible to uniformly mix and it is also impossible to prevent wall wetting due to accumulation of urea or the like.

Therefore, there still arises a problem that the flowability of the mixed gas is lowered due to the structural limitations, and the solidifying of the reducing agent is caused and the purification efficiency is lowered.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide an exhaust gas purifying apparatus and a method for reducing nitrogen oxide, which are capable of maximizing NOx purifying performance by uniformly distributing a reducing agent before the exhaust gas is introduced into an SCR The present invention also provides a mixer device for use in a microwave oven.

The present invention relates to an air conditioner comprising an adapter portion disposed at the front end of an SCR device on an exhaust line and coupled with an injector, a casing portion including a body, an outer tube disposed on an inner circumferential side of the body, And a mixing section (1200) having a first blade section disposed between the outer tube and the body, and a second blade section disposed between the inner tube and the outer tube, wherein the second blade section is disposed in a direction opposite to the first blade section The present invention provides an SCR mixer apparatus for reducing NOx, which generates a rotational flow of SCR. Therefore, the efficiency of NH ₃ generation and equalization is improved.

The outer tube is preferably formed in a cylindrical shape and constitutes a chamfered injection space for introducing a reducing agent at a site where the injector is disposed.

The mixing unit may include at least one of a vertical supporting unit and a horizontal supporting unit that fixes the position of the outer tube and the inner tube and is supported on the inner peripheral surface of the body.

In one embodiment, the mixing section is provided with a lateral support section on the inflow side of the exhaust gas and a longitudinal support section on the outflow side, wherein the lateral support section is configured such that all or a part of the reducing agent injected from the injector is supplied to the first blade section or the second blade It is possible to prevent falling directly to the lower space before reaching the part.

The outer tube and the inner tube may have a plurality of flow holes through which the reducing agent and the exhaust gas can flow in the inner and outer circumferential spaces.

The mixing unit may further include at least one lower member coupled to the lower side of the outer tube and temporarily storing the reducing agent flowing through the surface of the outer tube or through the flow hole and lifting the reducing agent by rotational flow.

It is preferable that the lower member is symmetrically arranged on both sides with respect to the longitudinal center line of the outer tube, and the end portion is formed to be inclined upward.

The casing portion may further include a temperature sensor mounting portion disposed at a rear end of the adapter portion and having a temperature sensor mounted thereon with the temperature of the exhaust gas flowing into the SCR device. And a NOx sensor mounting portion to which a NOx sensor capable of measuring the concentration of nitrogen oxide can be mounted.

On the other hand, the present invention is characterized in that it comprises an adapter unit disposed at the front end of the SCR apparatus on the exhaust line and coupled with the injector, a casing unit 1100 including a cylindrical body, a cylindrical outer appearance disposed on the inner peripheral side of the body, A first space generating a rotational flow in one direction between an inner circumference and an outer circumference of the body by an inner tube disposed on the inner circumference side, a second space generating a rotational flow in a direction opposite to the first space between the outer tube and the inner tube, And a mixing section (1200) which is divided into a third space formed on the inner circumference side of the inner tube and has a plurality of flow holes through which a reducing agent can pass in a radial direction between the first to third spaces The present invention provides a mixer apparatus for an SCR.

According to the present invention, it is possible to maximize the NH ₃ flow uniformity at the front end of the SCR apparatus, thereby significantly reducing the emission amount of nitrogen oxides, thereby minimizing environmental pollution. Particularly, in the case of diesel vehicles, the emission of pollutants due to aging has increased dramatically, and international restrictions on the emission of nitrogen oxides are increasing. Therefore, in response to the request for solving environmental pollution problems worldwide, it is possible to contribute to the reduction of nitrogen oxides do.

Further, since the present invention can be simply installed while minimizing the structural change and the addition of the apparatus on the conventional exhaust line, the productivity is improved and the economical effect is obtained.

1 is a block diagram showing a conventional SCR system.
2 is a front sectional view of a mixer apparatus for SCR for reducing nitrogen oxides according to the present invention.
3 is a front view showing a mixing unit in an SCR mixer apparatus for reducing NOx in FIG. 2;
4 is a perspective view of the mixing unit viewed from one side.
5 is a side view for explaining the operation of the inner and outer tubes and the blades in the SCR mixer apparatus for reducing nitrogen oxides of the present invention.
6 is a schematic diagram for explaining an SCR system to which a mixer device for SCR for reducing nitrogen oxides according to the present invention is applied.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a mixer for SCR for reducing nitrogen oxides according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the following description, when a part is referred to as being 'connected' to another part, it includes not only a direct connection but also a case where another part or device is connected in between. In addition, when a part is referred to as including an element, it is to be understood that the element may include other elements, not the exclusion of any other element, unless specifically stated otherwise.

The present invention basically comprises an adapter unit disposed at the front end of the SCR apparatus on an exhaust line and having an injector coupled thereto, a casing unit including a body, an outer tube spaced from the inner circumferential side of the body, And a second blade portion disposed between the inner tube and the outer tube, wherein the second blade portion is rotatable in a direction opposite to the rotation direction of the first blade portion Provided is a mixer apparatus for SCR for reducing nitrogen oxide which generates a flow.

The exhaust line described in the present invention can be understood to mean a gas exhaust path of an internal combustion engine vehicle mainly composed of diesel as a combustion source. However, it can be applied not only to various facilities for industrial or domestic use, .

The SCR apparatus chemically reacts nitrogen oxides (NOx) in the exhaust gas with a reducing agent such as ammonia (NH ₃ ), urea (Urea) or the like in the catalyst layer to decompose into harmless water and nitrogen And then it can be applied in various forms.

The injector used in the present invention mainly injects urea, CO (NH ₂ ) ₂ ) at the front end of the SCR device and thermally decomposes and hydrolyzes the vaporized NH ₃ to reduce nitrogen oxides (NO x) in the exhaust gas However, the reducing agent is not necessarily limited to urea water.

It is expected that the reduction efficiency of nitrogen oxides will increase as the reducing agent injected from the injector is diffused and distributed evenly on the inflow side of the SCR device. However, in practical application, urea injected into the injector flows to the bottom of the exhaust pipe, There is a problem that the decomposition efficiency is reduced. The SCR mixer apparatus for reducing nitrogen oxides according to the present invention can constitute a so-called urea dosing system for solving such a problem, and will be described in more detail below.

2 is a front sectional view of a mixer apparatus for SCR for reducing nitrogen oxides according to the present invention.

On the basis of the drawings, one side is defined as the side where the exhaust gas flows into the internal space and the other side is defined as the exhaust side.

The mixer apparatus 1000 of the present invention is installed in a casing unit 1100 and a casing unit 1100 which form an outer appearance and is mixed with an exhaust gas by being dispersed in a reducing agent so as to be introduced into an SCR apparatus 2100 And a mixing unit 1200 that mixes the signals.

The casing unit 1100 may have a generally cylindrical body 1101 as a basic skeleton and may include inlet openings and outlets (not shown), which are predetermined openings on both sides. It is preferable that the casing unit 1100 is sealed outside a predetermined apparatus or a mounting site of the members so that the air or the exhaust gas from the outside can be blocked from flowing out.

A predetermined plunger 1102 may be provided on both sides of the body 1101 for connection to the exhaust pipe and / or the SCR device. The plunger 1102 may be tightly coupled with the plunger formed at one end of the exhaust pipe or the SCR device, have. It goes without saying that a predetermined gasket may be interposed in this fastening.

An adapter unit 1110 may be formed in a manner that communicates the inside and the outside of the body 1101. Such an adapter unit 1110 performs a function of inserting and fastening an injector to be described later. The arrangement of the adapter unit 1110 is preferably formed on the upper side of the casing unit 1100 in consideration of the action of the selective or gravity force. More preferably, the adapter unit 1110 is formed adjacent to the inlet port side in consideration of the arrangement state of the mixing unit 1200 .

In addition, the injector injects a reducing agent and mixes with the exhaust gas in the mixing unit 1200 to be introduced into the SCR apparatus 2100, so that the adapter unit 1110 is adjacent to the outlet side toward the lower side for smooth flow guidance. It is preferable that it is formed in an inclined form.

One or more mounting portions for mounting a sensor for predetermined sensing may be formed in the casing portion 1100. For example, the NOx sensor mounting portion 1122 may be disposed adjacent to the inlet port side, The sensor mounting portion 1121 can be disposed.

The mounting portions can measure the concentration and the temperature of the nitrogen oxide in the process of flowing the exhaust gas by combining the NOx sensor and the temperature sensor, respectively. The concentration and the temperature of the nitrogen oxide are important factors for the decomposition efficiency of the SCR device . Accordingly, the controller may control the injection amount and / or injection frequency of the injector to be described later according to the sensing values.

A mixing unit 1200 including an outer pipe 1210 and an inner pipe 1220 may be disposed on the inner circumferential side of the casing unit 1100. The outer pipe 1210 and the inner pipe 1220 are connected to the casing unit 1100 But it is not necessarily limited thereto.

It is preferable that the mixing unit 1200 is biased toward the rear end with respect to the side on which the adapter unit 1110 is disposed, for convenience of manufacture and economical efficiency.

The outer pipe 1210 and the inner pipe 1220 are each formed to be porous and function to allow the exhaust gas and the reducing agent to flow in and out of the outer and inner circumferential directions. As a plurality of ducts are provided, the exhaust gas is dispersed and mixed with the reducing agent Can be improved.

According to the arrangement of the outer tube 1210 and the inner tube 1220, a space in the radial direction is a first space between the casing portion 1100 and the outer tube 1210, a second space between the outer tube 1210 and the inner tube 1220, , And the third space on the inner circumferential side of the inner pipe 1220. [

A first blade portion 1310 may be disposed in the first space, and a second blade portion 1320 may be disposed in the second space.

The first blade portion 1310 and the second blade portion 1320 function to improve the mixing efficiency by generating rotational flow by the pressure of the exhaust gas. The blade portions 1320 are preferably formed to be inclined with respect to the central axis so as to generate rotating flows in mutually opposite directions.

It is contemplated that the blades are each formed as a continuous spiral or an arrangement of a plurality of blades. As shown in the figure, the first blade portion 1310 is disposed on the rear side in the longitudinal direction with respect to the second blade portion 1320 And the efficiency of mixing by the opposite rotational flow is improved. However, the arrangement and the shape of the blade portion are not necessarily limited to the examples shown in the drawings.

In this way, the mixing part 1200 divides the space into the outer tube 1210 and the inner tube 1220 in the casing part 1100, and forms a flow in the respective spaces opposite to each other, thereby effectively mixing the reducing agent in the exhaust gas Hereinafter, a specific embodiment of the mixing unit 1200 will be described.

3 is a front view showing a mixing unit in an SCR mixer apparatus for reducing NOx in FIG. 2;

As described above, the mixing unit 1200 may be formed such that the outer tube 1210 and the inner tube 1220 have the same central axis. In the illustrated state, only the first blade unit 1310 is apparently shown. The second blade portion 1320 is formed in a space between the outer tube 1210 and the inner tube.

The first blade portion 1310 may be coupled to the outer tube 1210 and the outer circumferential side portion may be disposed to contact the inner surface of the casing portion 1100 in consideration of the detachability of the mixing portion 1200. However, The second blade portion 1320 may be coupled at one end to the inner circumferential side of the outer tube 1210 and at the other end to the outer circumferential side of the inner tube 1220. [ It is preferable that the above connection is made by a welding method, but it is not limited thereto.

The outer tube 1210 and the inner tube 1220 may be formed with a plurality of flow holes 1211 and 1221 that can penetrate the inner and outer circumferential sides. The flow of the reducing agent may flow together with the exhaust gas flowing therebetween.

The outer tube 1210 may be formed in a chamfered shape so that a reducing agent can be introduced into the first and second space sides of the outer tube 1210 where the injector is disposed. As shown in the figure, . The inflow side space of the thus formed mixing unit 1200 is defined as an injection space 1240.

The reducing agent introduced into the first and / or second spaces through the injection space 1240 is divided into the outer pipe 1210 and the inner pipe 1220 so that the reducing agent is divided into the flow holes 1211 and 1221 In particular, the mixing efficiency is maximized by the rotational flow generated in the opposite direction in each space by the first blade portion 1310 and the second blade portion 1320.

Meanwhile, the reducing agent flowing down along the surface of the inner tube 1220 or the outer tube 1210 due to its own weight in spite of the generation and mixing of the flow, or the reducing agent flowing down through the flow holes 1211 and 1221, (1100). Such a reducing agent may not only be unnecessarily consumed but also become adhered to the flow, which may be a negative factor.

Therefore, as a further concept of the present invention, a lower member 1330, which is a structure protruding downward, may be formed at the bottom of the outer tube 1210.

The lower member 1330 functions to temporarily store the reducing agent flowing along the surface of the inner pipe 1220 or the outer pipe 1210 or the flow holes 1211 and 1221 so that the reducing agent can be temporarily lifted by the rotary flow while being temporarily stored For this purpose, the lower member 1330 is convex downward to provide a water storage space.

The lower member 1330 may be disposed as a single unit on the lower end side of the outer tube 1210. However, it is preferable that the lower members 1330 are symmetrically formed by being slightly offset from the center side bottom portion in the forward and backward directions.

FIG. 4 is a perspective view of the mixing unit viewed from one side, and FIG. 5 is a side view for explaining the operation of the inner and outer blades and the blades in the SCR mixer apparatus for reducing nitrogen oxides of the present invention.

An embodiment of the symmetrical arrangement of the lower member 1330 is shown on the perspective view. As shown in the figure, the lower member 1330 has a rib shape extending from the inflow side of the outer tube 1210 of the mixing unit 1200 to a side where the first blade unit 1310 is disposed, So that a water storage space is provided with a predetermined curved surface.

The lower member 1330 is formed so that the end portion thereof is directed upward, and performs a function of guiding the reducing agent, which has been accumulated by the rotating flow, to rise again.

The lower member 1330 may be formed symmetrically with respect to both sides of the central axis.

3, the mixing unit 1200 is formed such that the outer tube 1210 is spaced apart from the inner circumferential side of the casing unit 1100 by a predetermined distance. The first blade unit 1310 is disposed in a simple contact form, There may be a problem in structural stability.

One or more supporting portions may be further provided to fix the position by connecting the inner pipe 1220 and the outer pipe 1210 to each other and to be supported on the inner circumferential side of the casing portion 1100. [ For example, the support portion can be divided into a vertical support portion 1231 for supporting in the longitudinal direction and a horizontal support portion 1232 for supporting in the lateral direction.

The vertical support portion 1231 connects the inner tube 1220 and the outer tube 1210 to the outflow side of the mixing portion 1200 so that the upper and lower ends thereof can be supported by the upper and lower ends of the inside of the body of the casing portion 1100 And the lateral support 1232 on the inflow side can interconnect the inner tube 1220 and the outer tube 1210 so that both ends can be supported on the inner left and right sides of the body 1101 of the casing part 1100 have. However, the shape and arrangement of the vertical support portion 1231 and the horizontal support portion 1232 are optional.

The vertical supporting portion 1231 and the horizontal supporting portion 1232 are preferably plate-shaped in order to secure an area in the longitudinal direction to some extent for the purpose of enhancing the supporting force. In consideration of the flow of the exhaust gas and the inflow and outflow of the reducing agent, It is more preferable that they are formed.

It is preferable that the lateral support portion 1232 is formed on the inflow side in the form of a plate so as to prevent the reducing agent from flowing downwardly in response to the injection of the injector 1030. Such a lateral support portion 1232 includes an adapter portion 1110, And may be formed corresponding to a portion where the space 1240 is disposed.

The second blade portion 1320 is formed at a position before the first blade portion 1310 in the drawing. In this case, the reducing agent directly flowing into the second space from the injection space 1240 proceeds while rotating in one direction by the second blade portion 1320, and the reducing agent diffused to the outer circumference in the rotating process flows into the first space through the flow hole. And can be diffused along the other rotational flow.

In this process, the reducing agent flowing down due to its own weight is temporarily stored by the lower member 1330, and can be raised and mixed into the exhaust gas as described above.

6 is a schematic diagram for explaining an SCR system to which a mixer device for SCR for reducing nitrogen oxides according to the present invention is applied.

Described mixer apparatus 1000 of the present invention is configured in the previous stage of the SCR apparatus 2100 and can be coupled to the exhaust pipe by a predetermined plunger as described above.

Such a mixer apparatus 1000 may be installed directly on the rear end of the muffler in a state where a DPF (Diesel Particulate Filter Trap) or a Diesel Oxidation Catalyst (DOC) . The pump module and the sensor module as the dosing device for the urea water which is the reducing agent may be coupled to the SCR mixer device for reducing nitrogen oxides of the present invention, and will be described with reference to the drawings.

The injector 1030 is installed in the adapter unit 1110 and functions to inject the reducing agent supplied from a predetermined container (not shown) by the injector 1030 under the control of the controller unit 2200 in a fixed amount.

The controller unit 2200 can perform the adjustment of the proper injection amount and / or the control of the SCR apparatus 2100 by receiving the nitrogen oxide concentration feedback of the exhaust gas from the NOx sensor 1020 mounted on the NOx sensor mounting unit 1122. The measurement of the nitrogen oxide concentration may be performed selectively or additionally at the rear stage of the SCR apparatus 2100. For this purpose, the exhaust sensor 2110 may be further disposed at the rear end of the SCR apparatus 2100. [

On the other hand, at the rear end side of the mixer apparatus for SCR for reducing nitrogen oxides, the temperature is measured in the exhaust gas flowing into the SCR apparatus 2100, more precisely in the exhaust gas containing the reducing agent, A temperature sensor 1010 may be further disposed in the mounting portion 1121. [

On the other hand, the level sensor unit 3000 capable of measuring the storage level of the reducing agent may return the level signal to the controller unit 2200 so that the operator or the driver can be informed of the supplemental warning.

In an SCR system using an existing number of elements, it is necessary that the elements are mostly converted to NH ₃ at the front end of the SCR device and have a uniform flow distribution characteristic. The present invention can maximize NH ₃ generation and flow uniformity at the front end of the SCR device by constructing a mixer device for SCR for reducing nitrogen oxide so as to be able to meet such a demand, thereby advantageously reducing the emission amount of nitrogen oxides remarkably .

Further, the present invention has an economical advantage in that productivity can be improved because the facility can be simply installed while minimizing the structural change and the addition of the apparatus on the conventional exhaust line.

In the foregoing, the present invention has been described in detail based on the embodiments and the accompanying drawings. However, the scope of the present invention is not limited by the above embodiments and drawings, and the scope of the present invention will be limited only by the content of the following claims.

1000 ... mixer device 1010 ... temperature sensor
1020 ... NOx sensor 1030 ... injector
1100 ... casing portion 1101 ... body
1102 ... plunger 1110 ... adapter portion
1121 ... Temperature sensor mount 1122 ... NOx sensor mount
1200 ... Mixer 1210 ... Appearance
1211,1221 ... distribution hall 1220 ... inside
1231 ... Vertical support portion 1232 ... Horizontal support portion
1240 ... injection space 1310 ... first blade portion
1320 ... second blade portion 1330 ... lower member
2100 ... SCR device 2110 ... discharge sensor
2200 ... controller unit 3000 ... level sensor unit

Claims (10)

An adapter unit disposed at the front end of the SCR apparatus on the exhaust line and coupled with the injector, a casing unit 1100 having a body; And
A first blade portion disposed between the outer tube and the body; a second blade portion disposed between the inner tube and the outer tube to rotate in a direction opposite to the first blade portion; And a mixing portion 1200 having a second blade portion for generating a flow,
The mixing unit is supported on the inner circumferential surface of the body so as to fix the position of the outer tube and the inner tube and prevents the reducing agent sprayed from the injector from falling directly into the lower space before reaching the first blade portion or the second blade portion. And a horizontal support portion for supporting the SCR.
The method according to claim 1,
The above-
A mixer apparatus for SCR for reducing nitrogen oxides constituting an injection space in the form of a chamfer for introducing a reducing agent into a cylindrical shape at a site where the injector is disposed.
The method according to claim 1,
Wherein the mixing unit comprises:
A mixer device for SCR for reducing nitrogen oxides, further comprising a vertical supporting portion for fixing the position of an outer tube and an inner tube, wherein a horizontal support portion is provided on the inflow side of the exhaust gas and a vertical support portion is formed on the outflow side.
delete An adapter unit disposed at the front end of the SCR apparatus on the exhaust line and coupled with the injector, a casing unit 1100 having a body; And
A first blade portion disposed between the outer tube and the body; a second blade portion disposed between the inner tube and the outer tube to rotate in a direction opposite to the first blade portion; And a mixing portion 1200 having a second blade portion for generating a flow,
Wherein the mixing unit comprises at least one lower member coupled to the lower side of the outer tube and temporarily storing the reducing agent flowing through the surface of the outer tube or through the flow hole and rotating the reducing agent by rotational flow.
delete 6. The method of claim 5,
Wherein the lower member comprises:
And the end portions of the mixer are formed so as to be inclined upward, the mixer devices being arranged symmetrically with respect to the longitudinal centerline of the outer tube.
6. The method according to claim 1 or 5,
The casing unit includes:
And a temperature sensor mounting portion disposed at a rear end of the adapter portion and equipped with a temperature sensor capable of measuring the temperature of the exhaust gas flowing into the SCR device.
9. The method of claim 8,
The casing unit includes:
Further comprising a NOx sensor mounting portion disposed at a front end of the adapter portion and mounted with a NOx sensor capable of measuring the concentration of nitrogen oxide with respect to exhaust gas flowing into the SCR device.


delete

Images