KR20230067319A - Exhaust gas treatment apparatus - Google Patents

Abstract

The present invention provides an exhaust gas treatment apparatus capable of improving effect of removing nitrogen oxide from a selective catalytic reduction reactor by effectively separating soot. According to an embodiment of the present invention, the exhaust gas treatment apparatus includes: an exhaust pipe including an outlet unit and an inlet unit into which exhaust gas including the soot generated in a combustion engine flows, wherein the exhaust gas is discharged from the outlet unit; a wing unit installed in the exhaust pipe between the inlet unit and the outlet unit and generating a centrifugal force by rotating the exhaust gas; a soot collecting tank collecting the soot separated from the exhaust gas as at least a part in the exhaust pipe between the wing unit and the outlet unit protrudes; a spray nozzle spraying at least one among ammonia, an ammonia aqueous solution, and a urea solution to the inside of the exhaust pipe between the inlet unit and the outlet unit; and a backflow prevention unit preventing backflow of the soot by being installed in the soot collecting tank.

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 nitrogen oxide removal effect of a selective catalytic reduction reactor by effectively separating soot, an inflammable substance contained in exhaust gas. it's 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 and passes it through a catalyst layer to react 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 of 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 includes 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. An exhaust pipe, a wing part installed inside the exhaust pipe between the inlet part and the outlet part to generate centrifugal force by rotating the exhaust gas, and at least a part of the exhaust pipe between the wing part and the outlet part protrudes, A soot collection tank for collecting the soot separated from the exhaust gas, a spray nozzle for injecting at least one of ammonia, ammonia aqueous solution, and urea water into the exhaust pipe between the inlet and the outlet, and the soot collection tank and a backflow prevention unit installed on the soot to prevent backflow of the suit.

The backflow prevention unit may be installed at a soot outlet in which a part of the exhaust pipe is opened and connected to the soot collection tank.

In the backflow prevention unit, an area of an inlet through which the soot is introduced may be larger than an area of an outlet through which the soot is discharged into the soot collection tank.

The backflow prevention unit may include a fixing portion fixed to the soot outlet, and a blocking plate hinged to the fixing portion, blocking the soot outlet and swinging only into the soot collection tank to open the soot outlet. .

The backflow prevention part may be formed in a plate shape in which an arc-shaped through hole through which the soot passes is formed, and one surface adjacent to the exhaust pipe is inclined toward the other surface adjacent to the soot collection tank.

The exhaust gas treatment device further includes a stepped portion formed inside the exhaust pipe between the soot collection tank and the outlet portion and having an inner diameter that decreases stepwise, and the soot outlet may be formed adjacent to the stepped portion. .

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. In particular, since the backflow prevention unit is installed in the soot collection tank, it is possible to prevent the collected soot from flowing back to the exhaust pipe.

1 is a use state diagram of 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 an operation diagram for explaining the operation of the exhaust gas treatment device.
4 is a view showing a backflow prevention unit according to another embodiment of the present invention.
5 is a view showing a backflow prevention unit according to another embodiment of the present invention.

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 3, an exhaust gas treatment device 1 according to an embodiment of the present invention will be described in detail.

1 is a use state diagram of 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 a soot collection tank (see 30 in FIG. 2 ). 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. In particular, since the backflow prevention unit (see 50 in FIG. 2 ) is installed in the soot collection tank 30 , it is possible to prevent the collected soot from flowing back to the exhaust pipe 10 .

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

FIG. 2 is a cross-sectional view of part A of FIG. 1 cut in the longitudinal direction.

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

The exhaust pipe 10 is a pipe for supplying exhaust gas containing soot generated in the combustion engine (EG) to the selective catalytic reduction reactor (SCR), and includes an inlet portion 10a connected to the combustion engine (EG), It includes an outlet part 10b connected to the selective catalytic 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 30 to be described later. The exhaust pipe 10 has a stepped portion 11 formed therein, and a wing portion 20, a soot collection tank 30, and a spray nozzle 40 are provided between the inlet portion 10a and the outlet portion 10b. can be installed

The stepped portion 11 is a portion whose inner diameter decreases stepwise, and may be formed inside the exhaust pipe 10 between the soot collection tank 30 and the outlet portion 10b, which will be described later. For example, the inner diameter of the exhaust pipe 10 decreases along the stepped portion 11 so that the inner diameter of the outlet portion 10b may be smaller than that of the inlet portion 10a. As the stepped portion 11 is formed inside the exhaust pipe 10, when the wings 20 generate centrifugal force on the exhaust gas, the soot separated from the exhaust gas is caught on the stepped portion 11 because it is relatively heavy and has large particles. It 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 20 generates centrifugal force by rotating exhaust gas, and may be installed inside the exhaust pipe 10 between the inlet portion 10a and the outlet portion 10b. More specifically, the wing portion 20 may be disposed between the inlet portion 10a and the stepped portion 11 . The shape of the wings 20 is not limited, but, for example, the body portion disposed in the center of the exhaust pipe 10, and radially arranged on the outer circumferential surface of the body portion are refracted along the circumferential direction of the exhaust pipe 10, and the end It may consist of a plurality of blades fixed inside the exhaust pipe 10 . That is, the wing part 20 is fixedly installed inside the exhaust pipe 10, and the exhaust gas can be rotated while flowing along the wing surface of the blade. When the wings 20 generate centrifugal force by rotating the exhaust gas, soot having relatively heavy and large particles is separated from the exhaust gas by the centrifugal force, moves away from the center of the exhaust pipe 10, and is easily collected in the soot collection tank 30. It can be. 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 40 to be described later can be easily mixed with the exhaust gas. However, the wing unit 20 is not limited to being composed of a body unit and a blade, and may be transformed into various structures capable of generating centrifugal force by rotating exhaust gas.

The soot collection tank 30 collects soot separated from exhaust gas, and may be formed by protruding at least a part of the exhaust pipe 10 between the wing portion 20 and the outlet portion 10b. At this time, as shown, the soot collection tank 30 may be formed by partially protruding to the outside of the exhaust pipe 10 between the wing 20 and the outlet 10b, and the wing 20 and the outlet The exhaust pipe 10 between the portions 10b may be formed by protruding partly into the exhaust pipe 10 . However, the soot collection tank 30 is not limited to being formed by protruding at least a portion of the exhaust pipe 10 between the wing portion 20 and the outlet portion 10b, and removes 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, the structure in which the soot collection tank 30 is formed by partially protruding outside of the exhaust pipe 10 between the wing portion 20 and the outlet portion 10b will be described with more emphasis.

The soot collection tank 30 has a collection space 30b formed therein, and a part of the exhaust pipe 10 is opened to form a soot outlet 30a connected to the soot collection tank 30. At this time, the soot outlet 30a may be formed adjacent to the stepped portion 11 . That is, the soot in the exhaust pipe 10 separated from the exhaust gas by the centrifugal force moves away from the center of the exhaust pipe 10 and is discharged through the soot outlet 30a and collected in the collecting space 30b. Since the soot outlet 30a is formed in the exhaust pipe 10 adjacent to the stepped portion 11, as described above, the soot is caught on the stepped portion 11 and does not flow into the outlet portion 10b, and the soot outlet 30a can be easily discharged. The collecting space 30b may be formed larger than the soot outlet 30a and extend from the outside of the exhaust pipe 10 toward the wing 20 to prevent the collected soot from escaping back to the soot outlet 30a. . In addition, the soot collection tank 30 may have at least one soot outlet 30c for discharging the soot collected in the collection space 30b to the outside, and the soot outlet 30c is a cover such as a manhole. It is closed by the part 60 and can be opened by the user when necessary. If necessary, a drain pipe (not shown) may be connected to the soot outlet 30c to immediately discharge the collected soot.

A backflow prevention unit 50 may be installed in the soot collection tank 30 . The backflow prevention unit 50 prevents the backflow of soot collected in the collecting space 30b and may be installed at the soot outlet 30a. The backflow prevention unit 50 is formed in a plate shape corresponding to the shape of the soot outlet 30a, and the area of the inlet through which the soot flows in may be larger than the area of the outlet through which the soot is discharged to the soot collection tank 30. there is. By installing the backflow preventing part 50 in the soot outlet 30a, it is possible to prevent the soot collected in the collection space 30b from escaping back to the exhaust pipe 10, thereby minimizing the inflow into the outlet 10b. there is. However, the backflow prevention unit 50 is not limited to being installed in the soot discharge port 30a, and the backflow prevention unit 50 may be installed in the collecting space 30b if necessary.

The injection nozzle 40 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 40 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 controls the direction in which the exhaust gas rotates. Taking this into consideration, it may be installed at a point after the exhaust gas has passed through the soot collection tank 30. Since the injection nozzle 40 is installed at a point after the exhaust gas has passed through the soot collection tank 30, when the aqueous ammonia solution or the urea solution is sprayed, liquid particles having a large mass enter the soot collection tank 30 together with the soot. capture can be prevented. The injection nozzle 40 may be installed at a position opposite to the soot collection tank 30, and at this time, the nozzle end 41 may be disposed to face the flow direction of the exhaust gas, and the center of the exhaust pipe 10 It can also be arranged to face. When the nozzle end 41 is disposed to face the flow direction of the exhaust gas, at least one of the injected ammonia, aqueous ammonia, and urea water flows through the exhaust pipe 10 together with the exhaust gas, increasing the mixing time. , The reaction between ammonia and nitrogen oxides can be effectively performed in the selective catalytic reduction reactor (SCR), and thus, the removal rate of nitrogen oxides can be increased. However, the injection nozzle 40 will be limited to being installed at a point after the exhaust gas has passed through the soot collection tank 30 or installed at a position opposite to the soot collection tank 30 in consideration of the direction in which the exhaust gas rotates. It is not, and the installation structure of the spray nozzle 40 may be variously modified. For example, the injection nozzle 40 may be installed at the front end of the wing part 20, installed on the same line as the wing part 20, or installed between the stepped part 11 and the outlet part 10b. In addition, the injection nozzle 40 may be installed on the same side as the soot collection tank 30 or installed in a vertical position.

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. 3, the operation of the exhaust gas treatment device 1 will be described in more detail.

3 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 material, from the exhaust gas at the front of the selective catalytic reduction reactor (SCR) and collect it in the soot collection tank 30. 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. In particular, since the backflow prevention unit 50 is installed in the soot collection tank 30, it is possible to prevent the collected soot from flowing back to the exhaust pipe 10.

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 rotated while passing through the wing 20 to generate centrifugal force. As the centrifugal force is generated in the exhaust gas, the heavy and large-sized soot is separated from the exhaust gas and deviates from the center of the exhaust pipe 10, and is discharged through the soot outlet 30a formed in the exhaust pipe 10 to the soot collection tank 30. is collected in the collection space 30b of Since the soot outlet 30a is formed adjacent to the stepped portion 11, the soot may be caught on the stepped portion 11 and discharged through the soot outlet 30a without flowing into the outlet portion 10b. The soot collected in the soot collection tank 30 is prevented from flowing back to the exhaust pipe 10 by the backflow prevention unit 50 and can be maintained in a state accommodated in the collection space 30b.

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 40, 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.

Meanwhile, when a large amount of soot is collected in the collecting space 30b, the user can separate the cover part 60 and open the soot outlet 30c to discharge the soot collected in the collecting space 30b to the outside. there is.

Hereinafter, with reference to FIG. 4, a backflow prevention unit 50 according to another embodiment of the present invention will be described in more detail.

4 is a view showing a backflow prevention unit according to another embodiment of the present invention.

The backflow prevention unit 50 according to another embodiment of the present invention includes a fixing portion 51 fixed to the soot outlet 30a, and a hinge coupled to the fixing portion 51 to block the soot outlet 30a and a soot collection tank ( 30) Includes a blocking plate 52 that swings only inward to open. The backflow prevention unit 50 according to another embodiment of the present invention includes a fixing portion 51 fixed to the soot outlet 30a, and a hinge coupled to the fixing portion 51 to block the soot outlet 30a and a soot collection tank ( 30) It is substantially the same as the foregoing embodiment except for including the blocking plate 52 that is opened by swinging inward only. Therefore, this will be mainly described, but unless otherwise noted, the description of the remaining components will be replaced with the above-described items.

The backflow prevention unit 50 includes a fixing unit 51 and a blocking plate 52 . The fixing part 51 is formed in a plate shape corresponding to the shape of the soot outlet 30a and fixed to the soot outlet 30a, and a through hole 51a overlapping the soot outlet 30a may be formed on one side. there is. In the drawings, a single through-hole 51a is shown as being formed in a semicircular shape in the fixing part 51, but it is not limited thereto, and the shape and number of through-holes 51a may be increased or decreased as needed. The blocking plate 52 is hinged to the fixing part 51 to block the soot outlet 30a, more specifically, the through hole 51a overlapping the soot outlet 30a, and swing only inside the soot collection tank 30 Thus, the through hole 51a can be opened. For example, the blocking plate 52 maintains the through-hole 51a closed when exhaust gas or soot pressure is not applied, and exhausts the exhaust pipe 10 toward the soot collection tank 30. When gas or soot pressure is applied, the through-hole 51a may be opened while swinging around the hinge axis. Since the blocking plate 52 is hinged so as to swing only inside the soot collection tank 30, it is possible to effectively prevent the soot collected in the soot collection tank 30 from flowing back to the exhaust pipe 10.

Hereinafter, with reference to FIG. 5, a backflow prevention unit 50 according to another embodiment of the present invention will be described in more detail.

5 is a view showing a backflow prevention unit according to another embodiment of the present invention.

In the backflow prevention unit 50 according to another embodiment of the present invention, at least one arc-shaped through hole 50a through which soot passes is formed, and one surface adjacent to the exhaust pipe 10 is a soot collection tank. It is formed in a plate shape inclined toward the other surface adjacent to (30). In the backflow prevention unit 50 according to another embodiment of the present invention, at least one arc-shaped through hole 50a through which soot passes is formed, and one surface adjacent to the exhaust pipe 10 is a soot collection tank. Except for being formed in a plate shape inclined toward the other surface adjacent to (30), it is substantially the same as the above-described embodiment. Therefore, this will be mainly described, but unless otherwise noted, the description of the remaining components will be replaced with the above-described items.

The backflow prevention unit 50 is formed in a plate shape corresponding to the shape of the soot outlet 30a, is fixed to the soot outlet 30a, and has at least one arc-shaped through hole 50a through which the soot passes. is formed At this time, the reverse flow prevention unit 50 is formed such that one surface adjacent to the exhaust pipe 10 is inclined toward the other surface adjacent to the soot collection tank 30, and an area of one side of the through hole 50a adjacent to the exhaust pipe 10 The area of the other side of the through hole 50a adjacent to the soot collection tank 30 may be formed larger. The area of one side of the through-hole 50a adjacent to the exhaust pipe 10 is formed larger than the area of the other side of the through-hole 50a adjacent to the soot collection tank 30, so that the soot collected in the soot collection tank 30 is removed from the exhaust pipe ( 10) to minimize backflow. In the drawings, it is shown that two through-holes 50a are formed in the backflow prevention unit 50, but the present invention is not limited thereto, and the number of through-holes 50a may be increased or decreased as necessary.

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: stepped part
20: wing part 30: soot collection tank
30a: soot outlet 30b: collection space
30c: soot outlet 40: injection nozzle
41: nozzle end 50: backflow prevention unit
50a: through hole 51: fixing part
51a: through hole 52: blocking plate
60: cover
EG: combustion engine SCR: selective catalytic reduction reactor

Claims (6)

An exhaust pipe comprising 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 wing part installed inside the exhaust pipe between the inlet part and the outlet 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 outlet protrudes to collect the soot separated from the exhaust gas;
A spray nozzle for spraying at least one of ammonia, aqueous ammonia, and urea water into the exhaust pipe between the inlet and the outlet, and
An exhaust gas treatment device including a backflow prevention unit installed in the soot collection tank to prevent a backflow of the soot. According to claim 1,
The backflow prevention unit is an exhaust gas treatment device installed in a soot outlet in which a part of the exhaust pipe is opened and connected to the soot collection tank. The method of claim 2, wherein the backflow prevention unit,
An exhaust gas treatment device in which an area of an inlet through which the soot is introduced is larger than an area of an outlet through which the soot is discharged into the soot collection tank. The method of claim 2, wherein the backflow prevention unit,
A fixing part fixed to the soot outlet;
An exhaust gas treatment device comprising a blocking plate hinged to the fixing part, blocking the soot outlet and swinging only inside the soot collection tank to open the soot outlet. The method of claim 2, wherein the backflow prevention unit,
An exhaust gas treatment device in which an arc-shaped through hole through which the soot passes is formed, and one surface adjacent to the exhaust pipe is formed in a plate shape inclined toward the other surface adjacent to the soot collection tank. According to claim 2,
Further comprising a step portion formed inside the exhaust pipe between the soot collection tank and the outlet portion, the inner diameter of which decreases stepwise,
The soot outlet is formed adjacent to the stepped portion.

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