KR102538626B1 - Exhaust gas treatment apparatus - Google Patents

Abstract

An exhaust gas treatment device is provided according to an embodiment of the present invention.
An exhaust gas treatment device according to an embodiment of the present invention includes an exhaust pipe including an inlet portion through which exhaust gas including soot generated from a combustion engine flows in and an outlet portion through which the exhaust gas is discharged, an inlet portion and an outlet portion. A stepped part formed inside the exhaust pipe between the parts, and the inner diameter decreases stepwise, and a wing part installed inside the exhaust pipe between the inlet part and the stepped part to generate centrifugal force by rotating the exhaust gas, and between the wing part and the stepped part. A soot collection tank in which at least a part of the exhaust pipe is protruded to collect the soot contained in the exhaust gas, and a spray nozzle for spraying at least one of ammonia, ammonia aqueous solution, and urea water into the exhaust pipe between the inlet and the outlet. can do.

Description

Exhaust gas treatment apparatus {Exhaust gas treatment apparatus}

The present invention relates to an exhaust gas treatment device, and more particularly, to an exhaust gas treatment device capable of improving the effect of removing nitrogen oxides in a selective catalytic reduction reactor by effectively separating soot, an inflammable substance contained in exhaust gas. It is about.

In general, various engines installed in ships generate power by burning fuel, and exhaust gas generated during the combustion of fuel contains harmful substances such as nitrogen oxides (NOx) and sulfur oxides (SOx). Since these harmful substances are a major cause of air pollution, it is necessary to remove them from exhaust gas. In general, sulfur oxides are removed using a wet scrubber, and nitrogen oxides are removed using a selective catalytic reduction (SCR). The selective catalytic reduction reactor injects urea water into the exhaust gas discharged from the engine, passes it through a catalyst layer, and reacts ammonia and nitrogen oxides generated by thermal decomposition of urea water, thereby converting the nitrogen oxides into water and nitrogen.

Meanwhile, soot, which is an inflammable material due to incomplete combustion of fuel, is also introduced into the selective catalytic reduction reactor. The soot adheres to the catalyst of the selective catalytic reduction reactor and interferes with the reaction of ammonia and nitrogen oxides. Therefore, in the prior art, a soot blower was installed in the selective catalytic reduction reactor to separate the soot attached to the catalyst, but there is a problem in that the soot blower is structurally complicated and manufacturing and installation costs increase as a separate soot blower is installed.

Accordingly, there is a need for an exhaust gas treatment device capable of improving the nitrogen oxide removal effect by separating the soot included in the exhaust gas with a simple structure.

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

A technical problem to be achieved by the present invention is to provide an exhaust gas treatment device capable of improving the nitrogen oxide removal effect in a selective catalytic reduction reactor by effectively separating soot, which is an inflammable material, contained in exhaust gas.

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 following description.

An exhaust gas treatment device according to an embodiment of the present invention for achieving the above technical problem is an exhaust pipe including an inlet portion through which exhaust gas including soot generated from a combustion engine is introduced and an outlet portion through which the exhaust gas is discharged. And, a step portion formed inside the exhaust pipe between the inlet portion and the outlet portion, the inner diameter of which decreases stepwise, and a centrifugal force installed inside the exhaust pipe between the inlet portion and the step portion to rotate the exhaust gas A soot collection tank for collecting the soot included in the exhaust gas by protruding at least a part of the exhaust pipe between the wing portion and the stepped portion, and between the inlet portion and the outlet portion. and an injection nozzle for injecting at least one of ammonia, aqueous ammonia, and urea solution into the exhaust pipe.

The injection nozzle may be installed at a position facing the soot collection tank.

The spray nozzle may be formed between the wing portion and the stepped portion, and a nozzle end portion may be disposed closer to the center of the exhaust pipe than to an inner circumferential surface of the stepped portion.

The injection nozzle may inject at least one of the ammonia, the ammonia aqueous solution, and the urea solution toward a direction in which the exhaust gas flows with a nozzle end formed toward the outlet.

The injection nozzle may be disposed between the stepped portion and the outlet portion.

In the exhaust pipe, an inner diameter of the outlet portion may be smaller than an inner diameter of the inlet portion as the inner diameter of the exhaust pipe becomes smaller with respect to the stepped portion.

The soot collection tank may include a soot outlet through which at least a portion of a surface in contact with the exhaust pipe and the soot collection tank is opened, and the soot in the exhaust pipe is discharged into the soot collection tank.

The soot outlet may be formed adjacent to the stepped portion rather than the wing portion.

The soot collection tank may include a soot discharge port that is selectively opened and closed to discharge the soot collected therein to the outside.

According to the present invention, soot, which is an inflammable substance included in exhaust gas, can be separated from the front end of the selective catalytic reduction reactor and collected in the soot collection tank. Therefore, it is possible to prevent the soot from adhering to the catalyst of the selective catalytic reduction reactor and interfering with the reaction of ammonia and nitrogen oxides, and thus, nitrogen oxides included in exhaust gas in the selective catalytic reduction reactor can be effectively removed.

1 is a diagram showing an exhaust gas treatment device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of part A of FIG. 1 cut in the longitudinal direction.
3 is a cross-sectional view taken along line BB of FIG. 2;
4 is an exemplary view showing a disposition state of injection nozzles.
5 is an operation diagram for explaining the operation of the exhaust gas treatment device.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only these embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to completely inform the person who has the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numbers designate like elements throughout the specification.

Hereinafter, with reference to FIGS. 1 to 5, an exhaust gas treatment device 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.

An exhaust gas treatment device 1 according to an embodiment of the present invention is a device for removing soot included in exhaust gas generated in a combustion engine (EG) and supplied to a selective catalytic reduction reactor (SCR) through an exhaust pipe 10. , for example, can be applied to ships.

The exhaust gas treatment device 1 may separate soot, which is an inflammable substance included in the exhaust gas, from the front of the selective catalytic reduction reactor (SCR) and collect it in the soot collection tank 40 . Therefore, it is possible to prevent the soot from adhering to the catalyst of the selective catalytic reduction reactor (SCR) and interfering with the reaction of ammonia and nitrogen oxides. There are features that can be effectively removed.

Hereinafter, with reference to FIGS. 2 to 4, the exhaust gas treatment device 1 will be described in detail.

FIG. 2 is a cross-sectional view taken along the longitudinal direction of part A of FIG. 1, FIG. 3 is a cross-sectional view taken along the line BB of FIG. 2, and FIG. 4 is an exemplary view showing the arrangement of spray nozzles.

An exhaust gas treatment device 1 according to the present invention includes an exhaust pipe 10, a stepped portion 20, a wing portion 30, a soot collection tank 40, and a spray nozzle 50.

The exhaust pipe 10 is a pipe for supplying exhaust gas including soot generated from the combustion engine EG to the selective catalytic reduction reactor (SCR), and includes an inlet 10a connected to the combustion engine EG and a selective catalyst. It includes an outlet part 10b connected to the reduction reactor (SCR). That is, the exhaust gas flows into the inlet 10a of the exhaust pipe 10 and is discharged through the outlet 10b. Combustion engines (EG) usually burn fossil fuels to generate various powers required for ships, so exhaust gases are generated by burning fossil fuels, and the generated exhaust gases contain a large amount of nitrogen oxides and soot due to incomplete combustion. may be included. Nitrogen oxides included in the exhaust gas cause air pollution and soot deteriorates the function of the selective catalytic reduction reactor (SCR), so it is necessary to remove them from the exhaust gas. Nitrogen oxides are removed in a selective catalytic reduction reactor (SCR), and since the selective catalytic reduction reactor (SCR) is a known technology, a detailed description thereof will be omitted. Soot may be collected in a soot collection tank 40 to be described later. A stepped portion 20 may be formed inside the exhaust pipe 10 .

The stepped portion 20 is a portion whose inner diameter decreases in steps, and may be formed inside the exhaust pipe 10 between the inlet portion 10a and the outlet portion 10b. For example, the inner diameter of the exhaust pipe 10 decreases along the stepped portion 20 so that the inner diameter d2 of the outlet portion 10b is smaller than the inner diameter d1 of the inlet portion 10a. As the stepped portion 20 is formed inside the exhaust pipe 10, when the wing portion 30, which will be described later, generates centrifugal force in the exhaust gas, soot separated from the exhaust gas due to its relatively heavy and large particles is placed on the stepped portion 20. It is caught and cannot flow into the outlet part 10b, and thus, it is possible to prevent soot from flowing into the selective catalytic reduction reactor (SCR).

The wing portion 30 generates centrifugal force by rotating exhaust gas, and may be installed inside the exhaust pipe 10 between the inlet portion 10a and the stepped portion 20 . The shape of the wing portion 30 is not limited, but, for example, the body portion disposed in the center of the exhaust pipe 10 and the outer circumferential surface of the body portion are radially arranged and refracted along the circumferential direction of the exhaust pipe 10. It may consist of a plurality of blades fixed inside the exhaust pipe 10 . That is, the wing part 30 is fixedly installed inside the exhaust pipe 10, and the exhaust gas can rotate while flowing along the wing surface of the blade. As the wing part 30 rotates the exhaust gas to generate centrifugal force, as described above, the relatively heavy and large-particle soot is separated from the exhaust gas by the centrifugal force and moves away from the center of the exhaust pipe 10, and the soot collection tank 40 ) can be easily captured. In addition, since the exhaust gas is converted into a turbulent flow, at least one of ammonia, ammonia aqueous solution, and urea water sprayed from the injection nozzle 50 to be described later can be easily mixed with the exhaust gas.

The soot collection tank 40 collects the soot included in the exhaust gas, and may be formed by protruding at least a portion of the exhaust pipe 10 between the wing portion 30 and the stepped portion 20 . At this time, as shown, the soot collection tank 40 may be formed by partially protruding the exhaust pipe 10 between the wing part 30 and the stepped part 20 to the outside of the exhaust pipe 10, and the wing part The exhaust pipe 10 between the 30 and the stepped portion 20 may be formed to partially protrude toward the center of the exhaust pipe 10 . However, the soot collection tank 40 is not limited to being formed by protruding at least a part of the exhaust pipe 10 between the wing part 30 and the stepped part 20, and the soot separated from the exhaust gas by centrifugal force Any form is possible as long as the structure can be filtered and collected. Hereinafter, a structure in which the soot collection tank 40 is formed by protruding a part of the exhaust pipe 10 between the wing portion 30 and the stepped portion 20 to the outside of the exhaust pipe 10 will be described with more emphasis.

In the soot collection tank 40, at least a part of the surface in contact with the exhaust pipe 10 is opened to form a soot outlet 40a for collecting soot, and the soot outlet 40a is formed adjacent to the stepped portion 20, Soot in the exhaust pipe 10 may be discharged into the soot collection tank 40 . That is, the soot separated from the exhaust gas by the centrifugal force moves away from the center of the exhaust pipe 10 and is collected in the soot collection tank 40 through the soot outlet 40a. Since the soot outlet 40a is formed adjacent to the stepped portion 20, as described above, the soot is caught on the stepped portion 20 and is easily discharged through the soot outlet 40a without flowing into the outlet portion 10b. It can be. At least a part of the exhaust pipe 10 is expanded in the radial direction between the inlet part 10a and the outlet part 10b so that the inner diameter is larger than the inner diameter of the stepped part 20, and the internal space of the soot collection tank 40 is formed. Since this includes the extension portion 11, the soot discharged through the soot outlet 40a may be collected in the extension portion 11. The expansion part 11 may be formed to be larger than the soot outlet 40a and extend toward the wings 30 from the outside of the exhaust pipe 10 in order to prevent the collected soot from escaping back to the soot outlet 40a. . In addition, the soot collection tank 40 may be formed with a soot discharge port 40b through which soot collected therein is discharged to the outside. The soot discharge port 40b may be closed by a cover 41 such as a manhole, and may be selectively opened and closed by a user when necessary. If necessary, a drain pipe (not shown) may be connected to the soot outlet 40b to immediately discharge the collected soot. In the drawings, the soot outlet 40a is shown as being formed on a different surface from the inner diameter of the stepped portion 20, but is not limited thereto, and the soot outlet 40a is on the same surface as the inner diameter of the stepped portion 20. may be formed.

The injection nozzle 50 may inject at least one of ammonia, aqueous ammonia, and urea solution into the exhaust pipe 10 between the inlet 10a and the outlet 10b. One side of the injection nozzle 50 is connected to a storage tank (not shown) to receive at least one of ammonia, aqueous ammonia, and urea water, and the other side located inside the exhaust pipe 10 is provided by the wing 30 It may be installed at a point after the exhaust gas passes through the soot collection tank 40 in consideration of the direction in which the exhaust gas rotates. Since the injection nozzle 50 is installed at a point after the exhaust gas has passed through the soot collection tank 40, when the aqueous ammonia solution or the urea solution is sprayed, liquid particles having a large mass enter the soot collection tank 40 together with the soot. capture can be prevented. As shown in FIGS. 2 and 3, the injection nozzle 50 may be installed at a position opposite to the soot collection tank 40, and at this time, the nozzle end 51 faces the center of the exhaust pipe 10. It may be arranged so as to face the flow direction of the exhaust gas. However, the injection nozzle 50 will be limited to being installed at a point after the exhaust gas has passed through the soot collection tank 40 or installed at a position opposite to the soot collection tank 40 in consideration of the direction in which the exhaust gas rotates. It is not, and the installation structure of the spray nozzle 50 may be variously modified. For example, the injection nozzle 50 may be installed at the front end of the wing 30 or installed on the same line as the wing 30, installed on the same side as the soot collection tank 40, or installed in a vertical position. It could be.

Referring to FIG. 4 , the installation structure of the injection nozzle 50 may be variously modified. For example, the spray nozzle 50 is formed between the wing portion 30 and the stepped portion 20, as shown in (a) of FIG. 4, and the nozzle end 51 is the exhaust pipe 10 It is disposed toward the center, but may be disposed closer to the center of the exhaust pipe 10 than the inner circumferential surface of the stepped portion 20. Exhaust gas spread outward by the centrifugal force passes through the stepped portion 20 and is collected in the center to flow into the small-diameter outlet portion 10b. When the nozzle end 51 is disposed closer to the center of the exhaust pipe 10 than the inner circumferential surface of the stepped part 20, at least one of ammonia, ammonia aqueous solution, and urea water sprayed through the nozzle end 51 is collected in the center of the exhaust gas. Since it can be easily mixed in, the reaction between ammonia and nitrogen oxides can be effectively performed in the selective catalytic reduction reactor (SCR), and accordingly, the removal rate of nitrogen oxides can be increased.

In addition, as shown in (b) of FIG. 4, the injection nozzle 50 is formed so that the nozzle end 51 faces the outlet portion 10b toward the direction in which the exhaust gas flows, such as ammonia, aqueous ammonia, At least one of urea water may be injected. When the nozzle end 51 is formed to face the outlet part 10b, at least one of ammonia, ammonia aqueous solution, and urea water sprayed through the nozzle end 51 flows through the exhaust pipe 10 together with the exhaust gas and is mixed. Since the available time is increased, the reaction between ammonia and nitrogen oxides can be effectively performed in the selective catalytic reduction reactor (SCR), and accordingly, the removal rate of nitrogen oxides can be increased.

In addition, the injection nozzle 50 may be disposed between the stepped portion 20 and the outlet portion 10b, as shown in (c) of FIG. 4 . Exhaust gas flowing through the exhaust pipe 10 between the stepped portion 20 and the outlet portion 10b is in a state where the soot is separated and is collected in the center to have straightness. When the injection nozzle 50 is disposed between the stepped portion 20 and the outlet portion 10b, at least one of ammonia, ammonia aqueous solution, and urea water injected through the nozzle end 51 can be more easily mixed with the exhaust gas. Therefore, the reaction between ammonia and nitrogen oxides can be more effectively performed in the selective catalytic reduction reactor (SCR), and thus, the removal rate of nitrogen oxides can be further increased. In the drawing, the nozzle end 51 is shown as being disposed toward the center of the exhaust pipe 10, but is not limited thereto, and the nozzle end 51 may be disposed at the inlet 10a or the outlet 10b as necessary. It can also be placed facing up.

The exhaust gas treatment device 1 may be formed as a single piece and installed between the combustion engine (EG) and the selective catalytic reduction reactor (SCR), or may be formed in a unit form and formed in a plurality of units between the combustion engine (EG) and the selective catalytic reduction reactor. (SCR) may be connected in series.

Hereinafter, with reference to FIG. 5, the operation of the exhaust gas treatment device 1 will be described in more detail.

5 is an operation diagram for explaining the operation of the exhaust gas treatment device.

The exhaust gas treatment device 1 according to the present invention may separate soot, which is an inflammable substance included in the exhaust gas, from the front of the selective catalytic reduction reactor (SCR) and collect it in the soot collection tank 40. Therefore, it is possible to prevent the soot from adhering to the catalyst of the selective catalytic reduction reactor (SCR) and interfering with the reaction of ammonia and nitrogen oxides. can be effectively removed.

Referring to FIG. 5 , the exhaust gas containing nitrogen oxides and soot generated in the combustion engine (EG) is introduced into the inlet 10a of the exhaust pipe 10, and is rotated while passing through the wing 30 to generate centrifugal force. occurs As the centrifugal force is generated in the exhaust gas, the heavy and large-sized soot is separated from the exhaust gas and moved away from the center of the exhaust pipe 10, and is discharged through the soot outlet 40a formed in the exhaust pipe 10 to the soot collection tank 40. are captured in Since the soot outlet 40a is formed adjacent to the stepped portion 20, the soot may be caught on the stepped portion 20 and discharged through the soot outlet 40a without flowing into the outlet portion 10b. After the soot is removed, the exhaust gas with only nitrogen oxides remaining is mixed with at least one of ammonia, aqueous ammonia, and urea water injected from the injection nozzle 50, and then supplied to the selective catalytic reduction reactor (SCR) through the outlet part 10b. . Since the exhaust gas from which soot is removed is supplied to the selective catalytic reduction reactor (SCR), the reaction between ammonia and nitrogen oxides is increased in the selective catalytic reduction reactor (SCR), so that nitrogen oxides included in the exhaust gas can be effectively reduced.

On the other hand, when a large amount of soot is collected in the expansion part 11 constituting the inner space of the soot collection tank 40, the user separates the cover part 41 and opens the soot outlet 40b to open the expansion part 11 ) can be discharged to the outside.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art to which the present invention pertains can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. you will be able to understand Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting.

1: Exhaust gas treatment device
10: exhaust pipe 10a: inlet
10b: exit part 11: extension part
20: stepped part 30: wing part
40: soot collection tank 40a: soot outlet
40b: soot discharge port 41: cover portion
50: injection nozzle 51: nozzle end
EG: combustion engine SCR: selective catalytic reduction reactor

Claims (9)

an exhaust pipe including an inlet through which exhaust gas including soot generated from a combustion engine flows in and an outlet through which the exhaust gas is discharged;
a stepped portion formed inside the exhaust pipe between the inlet and the outlet, the inner diameter of which decreases stepwise;
a wing part installed inside the exhaust pipe between the inlet part and the stepped part to generate centrifugal force by rotating the exhaust gas;
A soot collection tank in which at least a part of the exhaust pipe between the wing portion and the stepped portion protrudes to collect the soot included in the exhaust gas; and
Including a spray nozzle for spraying at least one of ammonia, ammonia aqueous solution, and urea water into the exhaust pipe between the inlet and the outlet,
The exhaust gas treatment device of claim 1 , wherein an inner diameter of the exhaust pipe decreases with respect to the stepped portion so that an inner diameter of the outlet portion is smaller than an inner diameter of the inlet portion. According to claim 1,
The injection nozzle is an exhaust gas treatment device installed at a position facing the soot collection tank. According to claim 1,
The injection nozzle is formed between the wing part and the stepped part, and the nozzle end is disposed closer to the center of the exhaust pipe than the inner circumferential surface of the stepped part. According to claim 1,
The injection nozzle is an exhaust gas treatment device in which a nozzle end is formed toward the outlet and injects at least one of the ammonia, the aqueous ammonia solution, and the urea solution toward the direction in which the exhaust gas flows. According to claim 1,
The injection nozzle is an exhaust gas treatment device disposed between the stepped portion and the outlet portion. delete According to claim 1,
The soot collection tank includes a soot outlet through which at least a part of a surface in contact with the exhaust pipe and the soot collection tank is opened so that the soot in the exhaust pipe is discharged into the soot collection tank. According to claim 7,
The soot outlet is formed adjacent to the stepped portion rather than the wing portion. According to claim 1,
The exhaust gas treatment device of claim 1 , wherein the soot collection tank includes a soot discharge port that discharges the soot collected therein to the outside and is selectively opened and closed.

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