KR20240023906A - Exhaust gas treatment apparatus - Google Patents

Abstract

An exhaust gas treatment device is provided by one embodiment of the present invention.
An exhaust gas treatment device according to an embodiment of the present invention supplies exhaust gas discharged from a combustion engine to a selective catalytic reduction reactor, and includes an exhaust pipe including an inlet connected to the combustion engine and an outlet connected to the selective catalytic reduction reactor; At least one discharge port for spraying a reducing agent is formed through the outer peripheral surface, and is located inside the exhaust pipe between the inlet and the outlet, a reducing agent supply pipe that supplies at least one of ammonia, aqueous ammonia solution, and urea water as a reducing agent, and a sliding agent on the reducing agent supply pipe. Possibly combined, it may include a valve unit that opens the outlet when the exhaust gas moves upward and closes the outlet when it moves downward by gravity.

Description

Exhaust gas treatment apparatus {Exhaust gas treatment apparatus}

The present invention relates to an exhaust gas treatment device, and more specifically, to an exhaust gas treatment device in which a reducing agent is automatically injected when the exhaust gas temperature is above a certain temperature.

In general, various engines installed on ships generate power by burning fuel, and exhaust gases generated during the combustion process of fuel contain harmful substances such as nitrogen oxides and sulfur oxides. Since these harmful substances are a major cause of air pollution, they need to be removed from exhaust gases. Typically, sulfur oxides are removed in a wet scrubber, and nitrogen oxides are removed in a selective catalytic reduction reactor (SCR).

The selective catalytic reduction reactor reduces nitrogen oxides to nitrogen and water by passing exhaust gas mixed with a reducing agent through a catalyst layer installed inside the reactor, and gaseous ammonia is used as a reducing agent. However, gaseous ammonia is difficult to store and use due to its high risk of explosion and corrosiveness, so urea water stored in a tank is supplied to the front of the selective catalytic reduction reactor when necessary. The urea water supplied to the front of the selective catalytic reduction reactor is thermally decomposed by the exhaust gas and converted into gaseous ammonia. At this time, if the temperature of the exhaust gas is low, not only the conversion rate of urea water but also the reduction rate of nitrogen oxides decreases. Therefore, conventionally, the temperature of the exhaust gas was measured when the engine was running and urea water was injected only when the temperature was above a certain temperature, but there was an inefficiency problem as the operator directly controlled the injection of urea water.

Republic of Korea Patent No. 10-1758217 (2017.07.10.)

The technical problem to be achieved by the present invention is to provide an exhaust gas treatment device in which a reducing agent is automatically injected when the exhaust gas is above a certain temperature.

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

An exhaust gas treatment device according to an embodiment of the present invention for achieving the above technical problem supplies exhaust gas discharged from a combustion engine to a selective catalytic reduction reactor, and includes an inlet connected to the combustion engine and the selective catalytic reduction reactor. An exhaust pipe including a connected outlet portion, and at least one outlet for spraying a reducing agent on the outer circumferential surface are formed through the exhaust pipe, and are located inside the exhaust pipe between the inlet portion and the outlet portion to purify at least one of ammonia, aqueous ammonia solution, and urea water. It includes a reducing agent supply pipe that supplies the reducing agent, and a valve unit that is slidably coupled to the reducing agent supply pipe and opens the outlet when the exhaust gas moves upward and closes the outlet when it moves downward by gravity.

The valve unit may include a ring-shaped hub pipe body that is slidably coupled to the outer peripheral surface of the reducing agent supply pipe to open and close the outlet, and a plurality of blades extending outward from the hub pipe body.

The hub pipe body has a reducing agent accommodating space formed therein, at least one communication hole communicating with the reducing agent accommodating space and the outlet is formed through an inner surface in contact with the reducing agent supply pipe, and at least one injection port is provided on the outer surface. When the outlet is formed through the outlet and the communication port overlaps, the reducing agent may be injected into the exhaust pipe through the injection port.

The injection port is formed on an outer surface adjacent to the outlet portion and sprays the reducing agent toward the flow direction of the exhaust gas, or is formed on an outer surface adjacent to the inlet portion and sprays the reducing agent in a direction opposite to the flow direction of the exhaust gas. The reducing agent may be sprayed or formed on the outer surface between the blades to spray the reducing agent toward the inner peripheral surface of the exhaust pipe.

The reducing agent supply pipe may have an outer diameter gradually increased at the end to form a stepped portion that limits movement of the valve unit.

The reducing agent supply pipe includes a horizontal pipe at one end connected to a reducing agent storage tank located outside the exhaust pipe and the other end penetrating the exhaust pipe in the diametric direction, at least a portion of which is located inside the exhaust pipe, and extending vertically from the horizontal pipe and having an outer peripheral surface. It may include a vertical pipe in which the outlet is formed.

According to the present invention, when the exhaust gas exceeds a certain temperature, the force pushing the valve unit increases and the outlet formed in the reducing agent supply pipe is opened, so that the reducing agent can be automatically injected. As in the past, this method has the advantage of being structurally simple and easy to apply as it does not require a separate driving device to move the valve unit, as it is efficient because the operator does not have to directly control the spraying of the reducing agent.

1 is a diagram showing an exhaust gas treatment device according to an embodiment of the present invention.
FIG. 2 is a diagram showing portion A of FIG. 1 cut longitudinally.
3 and 4 are operational diagrams for explaining the operation of an exhaust gas treatment device according to an embodiment of the present invention.
Figure 5 is a diagram showing an exhaust gas treatment device according to another embodiment of the present invention.
Figure 6 is an operational diagram for explaining the operation of an exhaust gas treatment device according to another embodiment of the present invention.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are merely provided to ensure that the disclosure of the present invention is complete and to be understood by those skilled in the art. 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 the specification.

Hereinafter, with reference to FIGS. 1 to 4, the exhaust gas treatment device 1 according to an embodiment of the present invention will be described in detail.

1 is a diagram showing an exhaust gas treatment device according to an embodiment of the present invention.

The exhaust gas treatment device 1 according to an embodiment of the present invention is a device that supplies a reducing agent to the exhaust gas generated from the combustion engine (EG) and supplied to the selective catalytic reduction reactor (SCR) through the exhaust pipe 10, For example, it can be applied to ships.

In the exhaust gas treatment device (1), when the exhaust gas exceeds a certain temperature, the force pushing the valve unit (see 30 in FIG. 2) increases, and the outlet formed in the reducing agent supply pipe (see 20 in FIG. 2) (see 20a in FIG. 2) ) is open, so the reducing agent can be automatically sprayed. As in the prior art, the operator does not have to directly control the spraying of the reducing agent, so it is not only efficient, but also structurally simple and easy to apply because it does not require a separate driving device to move the valve unit 30.

Hereinafter, with reference to FIG. 2, the exhaust gas treatment device 1 will be described in more detail.

FIG. 2 is a diagram showing portion A of FIG. 1 cut longitudinally.

The exhaust gas treatment device 1 according to the present invention includes an exhaust pipe 10, a reducing agent supply pipe 20, and a valve unit 30.

The exhaust pipe 10 supplies the exhaust gas discharged from the combustion engine (EG) to the selective catalytic reduction reactor (SCR). The inlet part 10a connected to the combustion engine (EG) and the selective catalytic reduction reactor (SCR) are connected to the exhaust pipe 10. It includes an outlet portion (10b). That is, the exhaust gas discharged from the combustion engine (EG) flows into the inlet portion (10a) of the exhaust pipe (10), is discharged through the outlet portion (10b), and is supplied to the selective catalytic reduction reactor (SCR). The exhaust gas flowing inside the exhaust pipe 10 comes into contact with the reducing agent supplied from the reducing agent supply pipe 20.

The reducing agent supply pipe 20 is located inside the exhaust pipe 10 between the inlet portion 10a and the outlet portion 10b and supplies at least one of ammonia, ammonia solution, and urea water as a reducing agent, and is the length of the exhaust pipe 10. At least one outlet (20a) for spraying a reducing agent may be formed penetrating the outer peripheral surface of one side extending in this direction. A plurality of discharge ports 20a are formed spaced apart on the same plane along the outer peripheral surface of the reducing agent supply pipe 20, and each discharge port 20a has a circular or polygonal shape and can penetrate the reducing agent supply pipe 20. The reducing agent supply pipe 20 has a smaller diameter than the exhaust pipe 10 and includes a horizontal pipe 22 and a vertical pipe 23. The horizontal pipe 22 has one end connected to the reducing agent storage tank 24 located outside the exhaust pipe 10, and the other end penetrates the exhaust pipe 10 in the diametric direction, so that at least a portion of it may be located inside the exhaust pipe 10. . The vertical pipe 23 extends vertically from the other end of the horizontal pipe 22 in the longitudinal direction of the exhaust pipe 10, and an outlet 20a may be formed on the outer peripheral surface. That is, the reducing agent stored in the reducing agent storage tank 24 flows through the horizontal pipe 22 into the vertical pipe 23 and is supplied into the exhaust pipe 10 through the discharge port 20a. Although the vertical pipe 23 is shown in the drawing as extending toward the outlet portion 10b, it is not limited thereto, and the vertical pipe 23 may extend toward the inlet portion 10a if necessary. In addition, for convenience of explanation, the horizontal pipe 22 and the vertical pipe 23 are described separately, but the horizontal pipe 22 and the vertical pipe 23 are of an integrated structure, and each region of the reducing agent supply pipe 20 is It may be compartmentalized. The valve unit 30 may be slidably coupled to this reducing agent supply pipe 20.

The valve unit 30 opens and closes the discharge port 20a and can be slidably coupled to the vertical pipe 23. More specifically, the valve unit 30 moves to the upper part adjacent to the outlet part 10b by exhaust gas to open the outlet 20a, and moves to the lower part adjacent to the inlet part 10a by gravity to open the outlet 20a. ) can be closed. For example, in the initial state where the temperature of the exhaust gas flowing into the inlet 10a is low, the flow rate of the exhaust gas is slow and the force pushing the valve unit 30 upward is weak, so the valve unit 30 is connected to the outlet ( It overlaps with 20a) and the outlet (20a) can be closed. When the discharge port 20a is closed, the reducing agent cannot be supplied into the exhaust pipe 10 and may remain contained within the reducing agent supply pipe 20. As the temperature of the exhaust gas flowing into the inlet 10a increases, the flow rate of the exhaust gas increases and the force pushing the valve unit 30 upward increases, so the valve unit 30 moves upward and reaches the outlet 20a. can be opened. When the discharge port 20a is opened, the reducing agent inside the reducing agent supply pipe 20 can be supplied into the exhaust pipe 10. Only when the exhaust gas rises above a certain temperature, the valve unit 30 opens the outlet 20a and the reducing agent is automatically sprayed, so that when an ammonia solution or urea water is used as a reducing agent, conversion to ammonia is easily accomplished. Reduction of nitrogen oxides can also be easily accomplished in a selective catalytic reduction reactor (SCR). In addition, it is efficient because the operator does not have to directly control the spraying of the reducing agent as in the prior art, and it also has the advantage of being structurally simple because a separate driving device for moving the valve unit 30 is not required. Since the reducing agent supply pipe 20 is formed with a step 21 whose outer diameter gradually increases at the end of the vertical pipe 23, the valve unit 30 has a range of movement between the step 21 and the horizontal pipe 22. It is limited so that it can slide without leaving the reducing agent supply pipe (20).

The valve unit 30 includes a hub pipe body 31 and a plurality of blades 32 extending outward from the hub pipe body 31. The hub pipe body 31 is a ring-shaped member with a penetrating center, and is slidably coupled to the outer peripheral surface of the vertical pipe 23 of the reducing agent supply pipe 20 to open and close the discharge port 20a. The hub pipe body 31 has an inner diameter formed to be the same as the outer diameter of the vertical pipe 23 and is in close contact with the outer peripheral surface of the vertical pipe 23, and a plurality of blades 32 are radially arranged and coupled to the outer surface. The blade 32 rotates the exhaust gas to generate centrifugal force, and can be bent along the circumferential direction of the exhaust pipe 10. Since the exhaust gas flows and rotates along the wing surface of the blade 32 and is converted into turbulence, it can be easily mixed with the reducing agent.

Hereinafter, with reference to FIGS. 3 and 4, the operation of the exhaust gas treatment device 1 will be described in more detail.

3 and 4 are operational diagrams for explaining the operation of an exhaust gas treatment device according to an embodiment of the present invention.

In the exhaust gas treatment device (1) according to the present invention, when the exhaust gas exceeds a certain temperature, the force pushing the valve unit (30) increases and the outlet (20a) formed in the reducing agent supply pipe (20) is opened, so that the reducing agent is automatically discharged. can be sprayed. As in the past, the operator does not have to directly control the spraying of the reducing agent, so it is not only efficient, but also has the advantage of being structurally simple and easy to apply since a separate driving device for moving the valve unit 30 is not required.

The exhaust gas discharged from the combustion engine EG flows into the inlet 10a of the exhaust pipe 10, and simultaneously or sequentially, the reducing agent flows into the reducing agent supply pipe 20. In the initial state where the temperature of the exhaust gas flowing into the inlet 10a is low, the flow rate of the exhaust gas is slow and the force pushing the valve unit 30 upward is weak, so as shown in FIG. 3, the valve unit 30 ) can be maintained in a lowered state. If the valve unit 30 is maintained in the lowered state, the discharge port 20a is closed, and the reducing agent cannot be supplied into the exhaust pipe 10 and may remain contained within the reducing agent supply pipe 20. The exhaust gas flows along the wing surface of the blade 32, is converted into turbulence, and is discharged to the outlet portion 10b.

As the temperature of the exhaust gas flowing into the inlet portion 10a increases, the flow rate of the exhaust gas increases and the force pushing the valve unit 30 upward increases, so as shown in FIG. 4, the valve unit 30 You can move to the top. Since the reducing agent supply pipe 20 is formed with a step 21 at the end, the movement of the valve unit 30 is restricted, thereby preventing it from leaving the reducing agent supply pipe 20. When the valve unit 30 moves upward, the outlet 20a is opened, and the reducing agent can be supplied into the exhaust pipe 10 through the outlet 20a. The reducing agent is decomposed into ammonia in contact with high-temperature exhaust gas, and the exhaust gas passes through the blade 32 together with ammonia, is converted into a turbulent flow, mixed with ammonia, and then discharged to the outlet portion 10b to create a selective catalytic reduction reactor (SCR). ) can be supplied.

Hereinafter, with reference to FIGS. 5 and 6, the exhaust gas treatment device 1-1 according to another embodiment of the present invention will be described in detail.

FIG. 5 is a diagram showing an exhaust gas treatment device according to another embodiment of the present invention, and FIG. 6 is an operational diagram for explaining the operation of the exhaust gas treatment device according to another embodiment of the present invention.

In the exhaust gas treatment device (1-1) according to another embodiment of the present invention, a reducing agent receiving space (31a) is formed inside the hub pipe body (31), and the reducing agent is injected into the exhaust pipe (10) through the hub pipe body (31). do. In the exhaust gas treatment device (1-1) according to another embodiment of the present invention, a reducing agent receiving space (31a) is formed inside the hub pipe body (31), and the reducing agent is injected into the exhaust pipe (10) through the hub pipe body (31). Except for this, it is substantially the same as the above-described embodiment. Therefore, this will be mainly explained, but unless otherwise stated, the description of the remaining components will be replaced by the above-mentioned details.

Referring to FIG. 5, the hub pipe body 31 has a reducing agent receiving space 31a formed therein, and at least one communication hole 31b may be formed through the inner surface in contact with the reducing agent supply pipe 20. The communication port (31b) communicates with the reducing agent receiving space (31a) and the outlet (20a), and may be formed in accordance with the number and location of the outlet (20a). The hub pipe body 31 has at least one injection hole 31c formed through the outer surface, so that when the discharge port 20a and the communication hole 31b overlap, the reducing agent will be injected into the exhaust pipe 10 through the injection hole 31c. You can. A plurality of injection holes 31c are arranged radially along the outer surface of the hub pipe 31, and each injection hole 31c may be formed in a circular or polygonal shape. At this time, as shown in (a) of FIG. 5, the injection hole 31c is formed on the outer surface adjacent to the outlet portion 10b and can spray the reducing agent toward the flow direction of the exhaust gas. When the reducing agent is injected toward the flow direction of the exhaust gas, the reducing agent naturally joins the center of the exhaust gas that passes through the blade 32 and is converted into a turbulent flow, and can be easily thermally decomposed and mixed. Alternatively, as shown in (b) of FIG. 5, the injection hole 31c may be formed on the outer surface adjacent to the inlet portion 10a to spray the reducing agent in a direction opposite to the flow direction of the exhaust gas. If the reducing agent is injected in a direction opposite to the flow direction of the exhaust gas, the time it is in contact with the exhaust gas increases and it passes through the blade 32 together with the exhaust gas, so that it can be more easily thermally decomposed and mixed. Alternatively, as shown in (c) of FIG. 5, the injection hole 31c may be formed on the outer surface between the blades 32 to spray the reducing agent toward the inner peripheral surface of the exhaust pipe 10. When the reducing agent is sprayed toward the inner peripheral surface of the exhaust pipe 10, the reducing agent joins the flow of the exhaust gas that flows and rotates along the wing surface of the blade 32 and can be easily thermally decomposed and mixed.

Referring to FIG. 6, the exhaust gas discharged from the combustion engine EG flows into the inlet 10a of the exhaust pipe 10, and simultaneously or sequentially, the reducing agent flows into the reducing agent supply pipe 20. As the temperature of the exhaust gas flowing into the inlet portion 10a gradually increases, the flow rate of the exhaust gas increases and the force pushing the valve unit 30 upward increases, and accordingly, the valve unit 30 can move upward. . When the valve unit 30 moves upward, the outlet (20a) and the communication port (31b) overlap, and the reducing agent passes through the reducing agent receiving space (31a) through the communication port (31b) and then through the injection port (31c). It can be supplied inside the exhaust pipe 10. The reducing agent is decomposed into ammonia in contact with high-temperature exhaust gas, and the exhaust gas passes through the blade 32 together with ammonia, is converted into a turbulent flow, mixed with ammonia, and then discharged to the outlet portion 10b to create a selective catalytic reduction reactor (SCR). ) can be supplied.

Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. You will be able to understand it. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

1: Exhaust gas treatment device
10: exhaust pipe 10a: inlet
10b: outlet 20: reducing agent supply pipe
20a: outlet 21: step portion
22: horizontal pipe 23: vertical pipe
24: reducing agent storage tank 30: valve unit
31: hub pipe 31a: reducing agent receiving space
31b: communication port 31c: injection port
32: blade
EG: Combustion engine SCR: Selective catalytic reduction reactor

Claims (6)

An exhaust pipe that supplies exhaust gas discharged from the combustion engine to the selective catalytic reduction reactor and includes an inlet connected to the combustion engine and an outlet connected to the selective catalytic reduction reactor;
At least one outlet for spraying a reducing agent is formed on the outer peripheral surface, and is located inside the exhaust pipe between the inlet and the outlet to supply at least one of ammonia, aqueous ammonia solution, and urea water as the reducing agent, and
An exhaust gas treatment device comprising a valve unit that is slidably coupled to the reducing agent supply pipe and opens the outlet when the exhaust gas moves upward and closes the outlet when it moves downward by gravity. The method of claim 1, wherein the valve unit is:
An exhaust gas treatment device comprising a ring-shaped hub pipe body that is slidably coupled to the outer peripheral surface of the reducing agent supply pipe to open and close the outlet, and a plurality of blades extending outward from the hub pipe body. The method of claim 2, wherein the hub tube body,
A reducing agent accommodating space is formed inside, at least one communication hole communicating with the reducing agent accommodating space and the outlet is formed through an inner surface in contact with the reducing agent supply pipe, and at least one injection hole is formed through an outer surface,
An exhaust gas treatment device in which the reducing agent is injected into the exhaust pipe through the injection port when the outlet and the communication port overlap. The method of claim 3, wherein the nozzle is:
It is formed on the outer surface adjacent to the outlet portion and sprays the reducing agent toward the flow direction of the exhaust gas,
It is formed on the outer surface adjacent to the inlet portion and sprays the reducing agent in a direction opposite to the flow direction of the exhaust gas, or
An exhaust gas treatment device formed on the outer surface between the blades and spraying the reducing agent toward the inner peripheral surface of the exhaust pipe. According to claim 1,
An exhaust gas treatment device in which an outer diameter of the reducing agent supply pipe is gradually increased at the end to form a stepped portion that limits movement of the valve unit. The method of claim 1, wherein the reducing agent supply pipe is:
A horizontal pipe at one end connected to a reducing agent storage tank located outside the exhaust pipe and the other end penetrating the exhaust pipe in the diametric direction and at least a portion of the pipe located inside the exhaust pipe;
An exhaust gas treatment device comprising a vertical pipe extending vertically from the horizontal pipe and having the outlet formed on an outer peripheral surface.

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