KR102204806B1 - Urea dosing unit for exhaust gas cleaning system - Google Patents

Abstract

The present invention is to provide a urea dosing unit for an exhaust gas treatment device capable of increasing space utilization, improving urea supply response speed, and facilitating maintenance and repair. According to the present invention, a urea dosing unit for an exhaust gas treatment device comprises: a housing part; a junction box installed in the housing part and connected to a cable from the outside; and a dosing block installed in the housing part and configured to supply urea delivered from a supply unit in a fixed amount to an injection unit. The dosing block may include: a block body having a flow path formed therein so that urea and compressed air can flow; and a plurality of hydraulic and pneumatic elements formed to be disposed on the flow path by being fastened to the block body, and configured to discharge urea and compressed air to the injection unit or to purge residual urea in the flow path according to a control mode.

Description

Urea dosing unit for exhaust gas treatment system {UREA DOSING UNIT FOR EXHAUST GAS CLEANING SYSTEM}

The present invention relates to a urea dosing unit for an exhaust gas treatment device.

The regulation of ships' exhaust gas has recently been expanded by international organizations such as IMO and governments of each country, and technical measures are being prepared for this. The exhaust gas emissions of ships that cause pollution include nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), PM, methane (CH ₄ ), and soot. Among these, nitrogen oxide treatment is a selective non-catalytic reduction method (SNCR) in which ammonia or ammonia water is injected into high-temperature exhaust gas in the temperature range of 870 ~ 1200 ℃ without a catalyst, and an exhaust gas recycling method that reduces nitrogen oxides by lowering the combustion temperature. Several methods have been proposed including (Exhaust Gas Recirculation; EGR), and the Selective Catalytic Reduction (SCR) system with proven performance, safety and economics is in the spotlight.

In order to install an exhaust gas treatment device such as SCR for treating nitrogen oxides on a ship, a problem is how to install it in a narrow space inside the ship. Unlike automobiles, if you have a large engine or multiple engines such as a ship or a plant, the exhaust gas emission also increases so that the size of the exhaust treatment system increases accordingly, and how to configure the treatment of gas emitted from multiple engines in terms of equipment. Whether or not it affects the efficiency.

SCR is classified into HC-SCR using hydrocarbon, H ₂ -SCR using hydrogen and NH ₃ -SCR using ammonia depending on the reducing agent used in the reaction. Among them, NH ₃ -SCR is divided into a method using anhydrous ammonia as it is and a method using urea (urea water). In the case of urea SCR, it has a system for supplying urea to the catalytic reactor. This dosing system can vary depending on the amount and temperature of the exhaust gas and the concentration of nitrogen oxides (NOx), so it has complex equipment and piping elements for automated control and monitoring and prevention of clogging caused by urea solidification. Becomes difficult. As an example, in the case of the dosing unit, products are installed in the direction of gravity in a whole piping type, which causes abnormal performance, and complicated piping is required to mount the check valve horizontally.

*Related prior art

Korean Patent Application Publication No. 10-2018-0075039 (published on July 4, 2018)

An object of the present invention is to provide a urea dosing unit for an exhaust gas treatment apparatus capable of improving space utilization by utilizing a block and shortening a piping line to improve urea supply response speed and facilitate maintenance or repair.

The urea dosing unit for an exhaust gas treatment apparatus according to the present invention includes: a housing portion; A junction box installed in the housing and for connecting cables from the outside; And a dosing block installed in the housing and configured to supply quantitatively urea delivered from the supply unit to the injection unit, wherein the dosing block includes: a block body having a flow path therein to allow urea and compressed air to flow; And a plurality of hydraulic-pneumatic elements formed to be disposed on the flow path by being fastened to the block body, and configured to discharge urea and compressed air to the injection unit or purify residual urea in the flow path according to a control mode. Can include.

As an example related to the present invention, the block main body includes: a first surface to be fixed to one inner surface of the housing and a second surface opposite to the first surface; A third surface orthogonal to the first surface and a fourth surface opposite to the third surface; And a fifth surface orthogonal to the first surface and the third surface, respectively, and a sixth surface opposite to the fifth surface.

As an example related to the present invention, the third surface includes: a first inlet port through which urea is introduced and a first outlet port through which urea is discharged; And a second inlet port through which compressed air is introduced and a second outlet port through which compressed air is discharged.

As an example related to the present invention, the third surface includes: a first pressure sensor configured to transmit an electrical signal by sensing a pressure of urea introduced through the first inlet port; A second pressure sensor for transmitting an electrical signal by sensing the pressure of urea supplied through the first outlet port; A third pressure sensor for transmitting an electrical signal by sensing the pressure of compressed air flowing through the second inlet port; And a fourth pressure sensor that senses the pressure of compressed air supplied through the second outlet port and transmits an electrical signal.

As an example related to the present invention, the fourth surface includes: a first on-off valve for opening and closing the urea; A second on-off valve and a third on-off valve arranged to change the flow path of compressed air by on-off combination according to the control mode; And it may include a flow control valve formed to control the flow rate of the urea.

As an example related to the present invention, the fourth surface includes: a first check valve disposed on a flow path of urea in the block body; And a second check valve and a third check valve disposed on the flow path of the compressed air in the block body.

As an example related to the present invention, the fifth surface may include a flow meter formed to measure the flow rate of the urea.

As an example related to the present invention, the sixth surface may include at least one regulator formed to control the pressure of the compressed air.

As an example related to the present invention, the second surface includes: a first ball valve configured to manually open/close the urea introduced through the first inlet port; A second ball valve configured to manually open and close the urea supplied through the first outlet port; A third ball valve configured to manually open and close the compressed air introduced through the second inlet port; And a fourth ball valve configured to manually open and close the compressed air supplied through the second outlet port.

As an example related to the present invention, the second surface includes: a first pressure gauge formed to directly recognize the pressure of urea flowing through the first inlet port; And a second pressure gauge formed to directly recognize the pressure of urea supplied through the first outlet port.

As an example related to the present invention, the third surface is arranged to face downward of the housing portion, the fourth surface is arranged to face upward of the housing portion, and the housing is fixed to the mounting target surface A plurality of brackets coupled to the rear to be able to; A ring portion formed on the upper surface to lift the housing portion; And at least one door portion formed to be opened and closed with respect to the housing.

As an example related to the present invention, the urea dosing unit for the exhaust gas treatment apparatus may further include a drain port disposed on a lower surface of the housing portion.

According to the urea dosing unit for an exhaust gas treatment apparatus according to the present invention, a flow path of urea and compressed air is implemented in a block-shaped dosing block, and various pneumatic elements arranged on the flow path are mounted in a form of fastening to the dosing block. Compared to installing elements in a complicated hose or pipe, the volume and installation space can be significantly reduced. Such a blocked dosing unit can shorten the piping line to improve the supply response characteristic of urea, and improve maintenance and maintenance of the dosing unit having a compact configuration.

In addition, by modularizing the whole, it is possible to ideally mount each part in the vertical/horizontal direction, and it is possible to realize the manifold of all parts by miniaturizing all parts and especially the flow control valve, which is a core part.

1 is a conceptual diagram schematically showing a urea dosing unit 100 for an exhaust gas treatment apparatus according to the present invention.
2 is a schematic side view of the urea dosing unit 100 for the exhaust gas treatment apparatus of FIG. 1.
FIG. 3 is a partially cut-away view of the urea dosing unit 100 for the exhaust gas treatment apparatus of FIG. 1 as viewed from the lower side.
FIG. 4 is a partially cut-away view of the urea dosing unit 100 for an exhaust gas treatment apparatus of FIG. 1 as viewed from above.
5 is a hydraulic circuit diagram of a urea dosing unit for an exhaust gas treatment apparatus according to the present invention.
6 and 7 are operational state diagrams for conceptually explaining a flow path in a dosing mode and a purging mode in the state of FIG. 5.
8 is a hydraulic circuit diagram of a urea dosing unit for an exhaust gas treatment apparatus according to another example related to the present invention, and is a diagram conceptually showing a flow path in a purging mode.

Hereinafter, a urea dosing unit for an exhaust gas treatment apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

1 to 4 are views conceptually showing a urea dosing unit 100 for an exhaust gas treatment apparatus according to the present invention.

As shown in FIG. 1, the urea dosing unit 100 for an exhaust gas treatment apparatus includes a housing portion 101 in which several parts are accommodated. A junction box 102 for connecting cables from the outside is installed inside the enclosure 101, and a dosing block 110 for quantitatively supplying urea delivered from the supply unit is disposed under the junction box 102 Has been. The housing unit 101 is compactly configured for easy installation and maintenance, and in addition, as shown in FIG. 2, the door unit 103 and the housing unit 101 are lifted to be opened and closed with respect to the housing unit 101 It is provided with a plurality of brackets 107 coupled to the rear to fix the hook portion 105 formed on the upper surface to be able to, the drain port 106 installed on the lower surface and the housing portion 101 to the mounting surface. I can.

The dosing block 110 includes a block body 120 having a flow path therein to allow urea and compressed air to flow, and various hydraulic and pneumatic elements that are fastened to the block body 120. These hydraulic and pneumatic elements are fastened to the block body 120 and are arranged on the flow path of the block body 120. Depending on the control mode, urea and compressed air are discharged to the injection unit or residual urea in the flow path is purged. It is structured to be able to.

In order to describe the various hydraulic and pneumatic elements installed in the block body 120, an installation surface of the block body 120 is defined. The block body 120 is a first surface 121 to be fixed to the inner surface of the housing unit 101, the second surface 122 facing the first surface 121, orthogonal to the first surface 121 The third surface 123, the fourth surface 124 facing the third surface 123, the fifth surface 125 and the fifth surface orthogonal to the first surface 121 and the third surface 123, respectively It has a sixth side 126 opposite to 125. 1 is a description of the elements arranged on the second surface 122 of the block body 120, and FIG. 3 is for elements installed on the fourth surface 124, and FIG. 4 is a third surface ( 123).

A first inlet port 131 through which urea is introduced and a first outlet port 132 through which urea is discharged are installed on the third surface 123 (lower surface) of the block body 120, and the first outlet port 132 A second inlet port 133 through which compressed air is introduced and a second outlet port 134 through which compressed air is discharged are disposed adjacent to each other. These ports 131, 132, 133, and 134 may simplify and unify a connection to an external supply unit or a spray unit or a connection line to a compressor.

In addition, as shown in FIG. 4, the third surface 123 has a first pressure sensor 191 and a first outlet port 132 that senses the pressure of urea flowing through the first inlet port 131 and transmits an electrical signal. A second pressure sensor 192 that senses the pressure of urea discharged through) and transmits an electrical signal, and a third pressure that transmits an electrical signal by sensing the pressure of compressed air flowing through the second inlet port 133 A sensor 193 and a fourth pressure sensor 194 for transmitting an electrical signal by sensing the pressure of compressed air discharged through the second outlet port 134 may be provided. These pressure sensors (191, 192, 193, 194) are those that provide electrical signals, unlike a pressure gauge of a visual confirmation method or a manually operated valve, which will be described later, and are concentrated on the third surface 123 with inlet/outlet ports. Can be placed.

The second surface 122 has a first ball valve 141 formed to manually open and close urea flowing through the first inlet port 131 and open and close the urea discharged through the first outlet port 132. Through the second ball valve 142 formed to be able to be formed, the third ball valve 143 formed to manually open and close the compressed air introduced through the second inlet port 133, and the second outlet port 134 It is provided with a fourth ball valve 144 and the like formed to manually open and close the discharged compressed air. In addition, a filter 146 for filtering the compressed air introduced through the second inlet port 133 is provided. The filter 146 may be provided with a fifth ball valve 145 so that it can be bypassed according to circumstances.

In addition, on the second side 122, the first pressure gauge 151 and the first outlet port 132 so that the pressure of urea flowing through the first inlet port 131 can be directly grasped at the site. A second pressure gauge 152 may be disposed to directly recognize the pressure of urea.

As shown in FIG. 3, the fourth surface 124 has a flow control valve 171 for finely adjusting the amount of urea to a signal of 4 to 20 mA, and a first on-off valve for opening and closing urea according to an electrical signal. A second on-off valve 173 and a third on-off valve 174 are disposed so as to change the flow path of compressed air according to 172 and the control mode. In addition, the fourth surface 124 includes a first check valve 181 disposed on the flow path of urea in the block body 120, and a second check valve 182 and a third check disposed on the flow path of compressed air. Valves 183 are provided respectively.

Referring to FIG. 1 again, a flow meter 148 formed to measure the amount of urea is installed on the fifth surface 125 of the block body 120, and the amount of compressed air can be adjusted on the sixth surface 126. The first regulator 161 and the second regulator 162 are disposed so as to be possible. The first regulator 161 and the second regulator 162 are valves for reducing the pressure of the compressed air supplied during purging and automizing, which will be described later. In addition, a third pressure gauge 153 formed to directly recognize the pressure of compressed air may be installed on the sixth surface 126.

In this way, the hydraulic elements are arranged separately on the second surface 122 to the sixth surface 126 of the block body 120 in which the flow path of urea and compressed air is internally formed in terms of functions, installation, and inspection. , It is easy to fasten or separate from the block body 120, and since the volume of the block body 120 can be reduced and the overall flow path can be shortened, the response characteristics of supplying urea can be improved.

Hereinafter, the urea dosing unit 100 for an exhaust gas treatment apparatus according to the present invention will be described using a hydraulic circuit diagram.

5 is a circuit diagram showing that the aforementioned hydraulic and pneumatic elements are implemented in the dosing block 110. The flow path of the urea and the flow path of the compressed air formed inside the dosing block 110 are installed to pass through various control or sensing elements while the urea and compressed air are sent to the respective inlets and outlets. The flow path of the compressed air is branched at one position by the second on-off valve 173 and the third on-off valve 174 and is connected to the flow path of urea.

The urea dosing unit 100 for an exhaust gas treatment apparatus according to the present invention may have a dosing mode and a purging mode. In the dosing mode, urea is controlled to supply urea and compressed air to the injection unit through the first outlet port 132 and the second outlet port 134, respectively. In the purging mode, compressed air is supplied to the block body 120. It is configured to discharge the remaining urea to the injection unit through the first outlet port (132).

6 shows the flow of urea and compressed air in the dosing mode. That is, urea is introduced through the first inlet port 131 and quantitatively controlled by a set amount through the first on-off valve 172 and the flow control valve 171, and the first check valve 181 and the second on-off It is discharged to the injection unit through the valve 173. At this time, the compressed air is also discharged to the injection unit through the filter 146 and the second regulator 162 through the third on-off valve 174 and the third check valve 183 at a constant pressure.

7 shows the flow of urea and compressed air in the purging mode. The supply of urea is cut off when the first on-off valve 172 is closed, and the second check valve 182 for compressed air by opening the second on-off valve 173 and blocking the third on-off valve 174 ) And sent to the euro of urea. The compressed air is discharged to the injection unit together with the residual urea in the flow path in the block body 120. At this time, the compressed air is blocked toward the flow control valve 171 by the first check valve 181.

8 is a hydraulic circuit diagram of a urea dosing unit for an exhaust gas treatment apparatus according to another example related to the present invention, and is a diagram conceptually showing a flow path in a purging mode. In this example, unlike FIG. 7, the branch flow path of compressed air is joined upstream of the flow control valve 171'. Accordingly, in the purging mode, residual urea is expanded to a pipe line including the flow control valve 171 ′ to further reduce the possibility of clogging due to solidification of urea.

The urea dosing unit for the exhaust gas treatment apparatus described as described above is not limited to the configuration and method of the described embodiments. The above embodiments may be configured by selectively combining all or part of each of the embodiments so that various modifications can be made.

100: urea dosing unit for exhaust gas treatment device
101: housing unit 102: junction box
103: door portion 105: hook portion
106: drain port 107: bracket
110: dosing block 120: block body
121: page 1 122: page 2
123: p. 3 124: p. 4
125: p. 5 126: p. 6
131: first inlet port 132: first outlet port
133: second inlet port 134: second outlet port
141: first ball valve 142: second ball valve
143: third ball valve 144: fourth ball valve
145: fifth ball valve 146: filter
148: flow meter 151: first pressure gauge
152: second pressure gauge 153: third pressure gauge
161: first regulator 162: second regulator
171: flow control valve 172: first on-off valve
173: second on-off valve 174: third on-off valve
181: first check valve 182: second check valve
183: third check valve 191: first pressure sensor
192: second pressure sensor 193: third pressure sensor
194: fourth pressure sensor

Claims (12)

Enclosure;
A junction box installed in the housing and for connecting cables from the outside; And
It is installed in the housing and includes a dosing block configured to quantitatively supply urea delivered from the supply unit,
The dosing block,
A block body having a flow path formed therein to allow urea and compressed air to flow; And
It is formed to be disposed on the flow path by being fastened to the block body, and includes a plurality of hydraulic and pneumatic elements formed to discharge urea and compressed air to the injection unit or to purge residual urea in the flow path according to a control mode, ,
The block body,
A first surface to be fixed to an inner surface of the housing and a second surface opposite to the first surface;
A third surface orthogonal to the first surface and a fourth surface opposite to the third surface; And
And a fifth surface orthogonal to the first surface and the third surface, respectively, and a sixth surface opposite to the fifth surface,
On the third side,
A first inlet port through which urea is introduced and a first outlet port through which urea is discharged;
A second inlet port through which compressed air is introduced and a second outlet port through which compressed air is discharged;
A first pressure sensor for transmitting an electrical signal by sensing a pressure of urea flowing through the first inlet port;
A second pressure sensor for transmitting an electrical signal by sensing the pressure of urea supplied through the first outlet port;
A third pressure sensor for transmitting an electrical signal by sensing the pressure of compressed air flowing through the second inlet port; And
A fourth pressure sensor that senses the pressure of compressed air supplied through the second outlet port and transmits an electrical signal is mounted,
On the fourth side,
A first on-off valve for opening and closing the urea;
A second on-off valve and a third on-off valve arranged to change the flow path of compressed air by on-off combination according to the control mode;
A flow control valve formed to control the flow rate of the urea;
A first check valve disposed on the flow path of urea in the block body; And
A second check valve and a third check valve disposed on the flow path of compressed air in the block body are mounted,
In the dosing mode, the urea flows through the first inlet port and is quantitatively controlled by a set amount through the first on-off valve and the flow control valve, and passes through the first check valve and the second on-off valve. To be discharged to the injection unit,
In the purging mode, the supply of the urea is cut off as the first on-off valve is closed, and the compressed air is closed to the second check valve by opening the second on-off valve and shutting off the third on-off valve. A urea dosing unit for an exhaust gas treatment device configured to be sent to the flow path of the urea through the urea.
delete delete delete delete delete The method of claim 1,
The fifth surface includes a flow meter formed to measure the flow rate of the urea, the urea dosing unit for an exhaust gas treatment device.
The method of claim 1,
The sixth surface includes at least one regulator formed to adjust the pressure of the compressed air, a urea dosing unit for an exhaust gas treatment device.
The method of claim 1,
The second side,
A first ball valve formed to manually open and close the urea introduced through the first inlet port;
A second ball valve configured to manually open and close the urea supplied through the first outlet port;
A third ball valve configured to manually open and close the compressed air introduced through the second inlet port; And
A urea dosing unit for an exhaust gas treatment apparatus comprising a fourth ball valve configured to manually open and close the compressed air supplied through the second outlet port.
The method of claim 9,
The second side,
A first pressure gauge formed to directly recognize the pressure of urea flowing through the first inlet port; And
A urea dosing unit for an exhaust gas treatment apparatus further comprising a second pressure gauge configured to directly recognize a pressure of urea supplied through the first outlet port.
The method of claim 1,
The third surface is disposed to face downwards of the housing portion, and the fourth surface is disposed to face upwards of the housing portion,
The housing part,
A plurality of brackets coupled to the rear surface so as to fix the housing unit to the mounting target surface;
A ring portion formed on the upper surface to lift the housing portion; And
A urea dosing unit for an exhaust gas treatment apparatus including; at least one door portion formed to be openable and closed with respect to the housing.
The method of claim 11,
A urea dosing unit for an exhaust gas treatment apparatus further comprising a drain port disposed on a lower surface of the housing part.

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