KR20180075039A - Selective catalytic reduction system - Google Patents

Abstract

The present invention relates to a selective catalytic reduction system for reducing nitrogen oxide contained in exhaust gas. The selective catalytic reduction system according to an embodiment of the present invention includes a burner supply module, a reducing agent dosing module, and an integrated compressed air supply device. The burner supply module includes a fuel supply unit for fuel supply and a first support frame supporting the fuel supply unit and formed in a block form. The reducing agent dosing module includes a reducing agent supply unit supplying a reducing agent for nitrogen oxide reduction and a second support frame supporting the reducing agent supply unit, formed in a block form, and separably coupled to the first support frame. The integrated compressed air supply device supplies compressed air to the burner supply module and the reducing agent dosing module.

Description

{SELECTIVE CATALYTIC REDUCTION SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a selective catalytic reduction system for reducing nitrogen oxides contained in an exhaust gas using a selective catalytic reduction reaction and more particularly to a selective catalytic reduction system capable of integrally controlling compressed air required in various fields will be.

Generally, a selective catalytic reduction (SCR) system is a system for reducing nitrogen oxides by purifying exhaust gas generated from a diesel engine, a boiler, and an incinerator.

The selective catalytic reduction system reacts the nitrogen oxides contained in the exhaust gas with the reducing agent while passing the exhaust gas and the reducing agent together in the reactor equipped with the catalyst, thereby reducing the nitrogen and the water vapor.

The selective catalytic reduction system uses ammonia (NH ₃ ) generated by directly spraying urea as a reducing agent to reduce nitrogen oxides or by hydrolyzing urea. And the reducing agent is supplied and injected through the reducing agent supply system.

On the other hand, in the selective catalytic reduction system, compressed air is used for various purposes.

For example, compressed air can be used to atomize the fuel injected into the burner, and can also be used to atomize the reducing agent when injecting the reducing agent. The compressed air may also be used to remove or clean the remaining reducing agent after stopping the injection of the reducing agent.

However, in the past, compressed air supply was performed independently for each required field. As a result, the overall configuration of the selective catalytic reduction system becomes complicated and the installation area occupied by the selective catalytic reduction system becomes large.

In addition, in the conventional selective reduction system, the burner, the reducing agent supply device, the compressed air supply device, and the like are independently provided, making it difficult to efficiently utilize the space.

As described above, since the overall configuration of the selective reduction system becomes complicated and efficient utilization of space becomes difficult, there is a problem that not only difficulty in initial installation but also maintenance becomes troublesome.

Further, in order to reduce nitrogen oxides, a reducing agent and compressed air are supplied to the injection nozzle to supply the atomized reducing agent into the high-temperature gas through the injection nozzle. In this case, when the urea is injected through the injection nozzle, the injected urea must undergo a thermal decomposition process. Therefore, the residence time for pyrolysis or hydrolysis is required before the injected urea is mixed with the exhaust gas and then reaches the catalyst.

Further, the amount of the reducing agent supplied varies depending on the operating conditions of the engine. That is, the amount of the nitrogen oxide contained in the exhaust gas varies depending on the operating condition of the engine, and the amount of the reducing agent required to reduce the amount of nitrogen oxide differs. When the reducing agent is supplied more than necessary, the ammonia used as the reducing agent may be discharged together with the exhaust gas. When ammonia is discharged together with the exhaust gas, it may become a new pollutant, so it is required to supply a proper amount of the reducing agent.

However, in the conventional reductant supply system, the amount of the reducing agent supplied varies according to the operating conditions of the engine, but the compressed air used for atomizing and atomizing the reducing agent is always supplied at a constant pressure.

Accordingly, there is a problem that the size of the reducing agent injection particles varies according to the operation conditions of the engine depending on the amount of the reducing agent supplied. The larger the particles of the injected reducing agent, the more retention time and the greater heat quantity are required for pyrolysis or hydrolysis. This is because the size of the evaporator in which pyrolysis or hydrolysis proceeds is increased, Thereby increasing the distance from the catalyst to the reactor equipped with the catalyst.

The increase in the size of the evaporator and the increase in the distance from the injector position of the reducing agent to the reactor equipped with the catalyst greatly restricts the selective catalytic reduction (SCR) system.

Further, if the compressed air is always supplied at a constant pressure, the difference between the pressure of the reducing agent and the pressure of the compressed air becomes large under the operating condition of the engine with a low reducing agent supply amount, . Specifically, when the pressure of the reducing agent is higher than the pressure of the compressed air, if the reducing agent is injected and becomes lower than the pressure of the compressed air of the reducing agent, irregular injection phenomenon may occur, in which the reducing agent is not sprayed.

The embodiments of the present invention provide a selective catalytic reduction system in which modularization is realized for each field in order to simplify the overall structure and facilitate maintenance.

According to an embodiment of the present invention, the selective catalytic reduction system includes a burner supply module, a reducing agent dosing module, and an integrated compressed air supply. The burner supply module includes a fuel supply part for supplying fuel and a first support frame formed in a block shape to support the fuel supply part. The reducing agent dosing module includes a reducing agent supply part for supplying a reducing agent for reducing nitrogen oxides, and a second support frame formed in a block shape for supporting the reducing agent supplying part and detachably coupled to the first supporting frame. An integrated compressed air supply supplies compressed air to the burner supply module and the reducing agent dosing module.

The selective catalytic reduction system may further include a burner that receives fuel from the fuel supply unit of the burner supply module. The burner may include a burner main body and a fuel injection portion.

The selective catalytic reduction system may further include a reducing agent injecting unit injecting the reducing agent supplied by the reducing agent supplying unit.

The reducing agent supply unit may include a reducing agent flow meter for measuring a flow rate of the reducing agent to be supplied to the reducing agent spraying unit and a reducing agent flow rate control valve for controlling a flow rate of the reducing agent supplied to the reducing agent spraying unit.

The burner supply module may further include a compressed air burner connection part that receives compressed air from the integrated compressed air supply device, transfers the compressed air to the burner, and is supported by the first support frame. The reducing agent dosing module may further include a compressed air reducing agent connection part that receives compressed air from the integrated compressed air supply device, transfers the compressed air to the reducing agent supply line and the reducing agent spraying part of the reducing agent supplying part, and is supported by the second supporting frame Ha

The integrated compressed air supply device supplies compressed air necessary for atomizing the fuel to be injected by the fuel injecting section of the burner, atomizes the reducing agent to be injected by the reducing agent injecting section, or cleans the reducing agent injecting section and the reducing agent supplying section It is possible to supply the compressed air necessary for the operation.

The burner supply module may further include a blower that supplies combustion air to the burner and is supported inside the first support frame.

The reducing agent dosing module may further include a washing water supply part supplying washing water to the reducing agent supplying part and the reducing agent spraying part and being supported inside the second supporting frame.

The selective catalytic reduction system may further include a fuel tank for storing the fuel to be supplied by the fuel supply unit, a reducing agent tank for storing the reducing agent to be supplied to the reducing agent supplying unit, and a washing water tank for storing the washing water to be supplied to the washing water supplying unit .

In addition, the selective catalytic reduction system described above can reduce nitrogen oxides contained in the exhaust gas discharged from an engine having a variable load. The integrated compressed air supply device supplies the compressed air supplied to the reducing agent spraying unit via the reducing agent dosing module and the pressure or flow rate of the compressed air supplied to the burner through the burner supply module according to the load fluctuation of the engine Can be adjusted.

As the load is lowered on the basis of when the load of the engine is the maximum load, the integrated compressed air supply apparatus is configured to reduce the compressed air supplied by the fuel injection unit to atomize the fuel to be injected and the reducing agent to be injected by the reducing agent injection unit The pressure or the flow rate of the compressed air to be supplied can be reduced, respectively.

Wherein the compressed air supply device supplies the compressed air supplied from the compressed air supply source to the reducing agent spraying unit and the fuel spraying unit, The pressure or the flow rate of the fluid can be adjusted.

The selective catalytic reduction system described above may include an electronic proportional pressure reducing valve (EPPRV).

The load of the engine can be calculated through one of the rotational speed of the engine, the rotational speed of the turbocharger mounted on the engine, or the scavenging pressure supplied to the engine.

The selective catalytic reduction system may further include a coupling member coupling the first support frame and the second support frame to each other.

The engaging member may include an engaging pin which is engaged with a part of the first supporting frame and a part of the second supporting frame.

The coupling member may include a hinge for rotatably connecting one area of the first support frame and one area of the second support frame.

The coupling member may include a cicada ring.

According to the embodiment of the present invention, the selective catalytic reduction system can realize the modularization in each field to simplify the overall structure and to facilitate the maintenance.

Further, according to the embodiment of the present invention, the selective catalytic reduction system can integrally control the supply of the compressed air used in various fields.

Further, according to the embodiment of the present invention, the selective catalytic reduction system can suitably supply as much compressed air as necessary in accordance with the load variation of the engine.

1 is a configuration diagram of a selective catalytic reduction system according to a first embodiment of the present invention.
2 is a perspective view showing a burner supply module and a reducing agent dosing module of the selective catalytic reduction system of FIG.
FIG. 3 is a perspective view showing a state in which the burner supply module and the reducing agent dosing module of FIG. 2 are separated.
Figure 4 is a top view of the burner supply module and the reducing agent dosing module of Figure 2;
FIG. 5 is a perspective view of a coupling member for coupling the burner supply module and the reducing agent dosing module of FIG. 1;
6 is a mapping graph for a compressed air supply used in a selective catalytic reduction system according to a modification of the first embodiment of the present invention.
7 is a perspective view illustrating a state in which the burner supply module and the reducing agent dosing module are rotated about one region in the selective catalytic reduction system according to the second embodiment of the present invention.
Figs. 8 and 9 are perspective views of the coupling members used in the selective catalytic reduction system of Fig.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In addition, in the various embodiments, components having the same configuration are denoted by the same reference symbols in the first embodiment. In the other embodiments, only components different from those in the first embodiment will be described.

The drawings are schematic and illustrate that they are not drawn to scale. The relative dimensions and ratios of the parts in the figures are shown exaggerated or reduced in size for clarity and convenience in the figures, and any dimensions are merely illustrative and not restrictive. And to the same structure, element or component appearing in more than one drawing, the same reference numerals are used to denote similar features.

The embodiments of the present invention specifically illustrate ideal embodiments of the present invention. As a result, various variations of the illustration are expected. Thus, the embodiment is not limited to any particular form of the depicted area, but includes modifications of the form, for example, by manufacture.

Hereinafter, a selective catalytic reduction (SCR) system 101 according to a first embodiment of the present invention will be described with reference to FIG.

For example, the selective catalytic reduction system 101 can reduce nitrogen oxides (NOx) contained in the exhaust gas discharged from an engine (not shown) having a variable load through a reduction reaction. Here, the engine may be a two-stroke low-speed or four-stroke medium-speed diesel engine used on a ship. However, the first embodiment of the present invention is not limited thereto, and the engine may be used in various fields such as a vehicle and a plant.

1, the selective catalytic reduction system 101 according to the first embodiment of the present invention includes a burner supply module 200, a reducing agent dosing module 300, and a compressed air supply device 500, .

The selective catalytic reduction system 101 according to the first embodiment of the present invention includes a reducing agent spraying unit 600, a burner 400, a coupling member 701 (shown in FIG. 5), a fuel tank 820, (830), and a washing water tank (860).

Further, although not shown, the selective catalytic reduction system 101 may further include a reactor provided with a catalyst for reducing nitrogen oxides therein, and an exhaust passage for moving the exhaust gas of the engine to the reactor.

The burner 400 burns the fuel to raise the temperature of the fluid. Specifically, the burner 400 can raise the temperature of the exhaust gas discharged from the engine and moving along the exhaust passage. For example, the burner 400 may be an oil burner or a plasma burner.

However, the first embodiment of the present invention is not limited to the above, and the object to be heated by the burner 400 may vary depending on the overall structure and type of the selective catalytic reduction system 101. That is, the burner 400 may increase the temperature of the exhaust gas before passing through the reactor or the temperature of the exhaust gas after passing through the reactor, or may raise the temperature of the outside air flowing into the selective catalytic reduction system 101.

Specifically, the burner 400 may include a burner main body 410 and a fuel injecting portion 470. The fuel injector 470 of the burner 400 receives fuel from the fuel supply unit 220 of the burner supply module 200 to be described later and can receive compressed air from the compressed air burner connection unit 240. The compressed air burner connection part 240 is connected to an integrated compressed air supply device 500 to be described later.

The fuel injector 470 injects the fuel supplied by the fuel supply unit 220 of the burner supply module 200 into the burner main body 210 through the compressed air burner connection unit 240, The compressed air can be supplied from the air supply device 500 and used to atomize the fuel supplied from the fuel supply unit 220.

The burner supply module 200 may include a fuel supply part 220 and a first support frame 205 (shown in FIG. 2). In addition, the burner supply module 200 may further include a compressed air burner connection part 240 and a blower 280.

The fuel supply unit 220 supplies fuel to be burned inside the burner body 410 of the burner 400. Specifically, the fuel supply unit 220 supplies the fuel stored in the fuel tank 820 to the burner 400, and may include a fuel supply pump, a fuel supply valve, a fuel filter, and the like. Here, the fuel tank 820 may be separately provided outside the burner supply module 200. However, the first embodiment of the present invention is not limited to the above, and the fuel tank 820 may be included in the burner supply module 200 as well.

The compressed air burner connection part 240 receives the compressed air from the integrated compressed air supply device 500 and transfers the compressed air to the burner 400.

The compressed air burner connection part 240 is installed in the compressed air burner connection line 241 connecting the integrated compressed air supply device 500 and the burner 400 and the compressed air burner connection line 241, And a compressed air burner connection valve 242 that opens and closes the connection line 241.

The blower 280 can supply air for combustion to the burner 400. [ In one example, the blower 280 may be a ring blower. Ring blowers are suitable for high wind pressure conditions with low air flow.

The first support frame 205 supports the fuel supply unit 220, the compressed air burner connection unit 240, and the blower 280. The first support frame 205 is formed in a block shape of various shapes and can be detachably coupled to a second support frame 305 to be described later.

Accordingly, the burner supply module 200 can be manufactured in various shapes according to the installation space, and can be easily combined with or separated from the reducing agent dosing module 300 described later.

The reducing agent dosing module 300 may include a reducing agent supply 310 and a second support frame 305. Further, the reducing agent dosing module 300 may further include a washing water supply part 360 and a compressed air reducing agent connecting part 380.

The reducing agent supply unit 310 supplies a reducing agent for reducing the nitrogen oxide to the reducing agent spraying unit 600 to be described later. At this time, the reducing agent supply unit 310 can supply the reducing agent stored in the reducing agent tank 830. Here, the reducing agent tank 830 may be separately provided outside the reducing agent dosing module 300. However, the first embodiment of the present invention is not limited to the above, and the reducing agent tank 830 may also be included in the reducing agent dosing module 300.

Specifically, the reducing agent supply unit 310 includes a reducing agent supply pump 320 for supplying the reducing agent stored in the reducing agent tank 830, a reducing agent supply line 331, a reducing agent injection control valve 347, The reductant supply control valve 333, the reducing agent supply control valve 332, the return line 336, the return valve 338, the reducing agent supply check valve 329, the reducing agent supply manual valve 334, the reducing agent supply manifold 350, A reducing agent drain valve 355, and an additional reducing agent pressure regulating valve 337. [

The reducing agent supply unit 310 may further include a filter 328 required for installing the reducing agent supply pump 320, a pressure gauge 326 for the reducing agent supply pump, a valve 327 for the reducing agent supply pump, and the like.

The reducing agent supply line 331 transfers the reducing agent supplied by the reducing agent supplying pump 320 to the reducing agent spraying unit 600 to be described later.

The reducing agent supply manifold 350 is used to distribute the reducing agent at a uniform flow rate when a reducing agent spraying unit 600 to be described later uses a plurality of nozzles.

The reducing agent drain line 355 is connected to the lower portion of the reducing agent supply manifold 350 so that the reducing agent, washing water, or foreign matter remaining in the reducing agent supply manifold 350 can be drained if necessary. The reducing agent drain valve 357 may be installed on the reducing agent drain line 355 to open or close the reducing agent drain line 355.

The reducing agent injection control valve 347 is provided in the reducing agent supply line 331 to control whether or not the reducing agent spraying unit 600 injects the reducing agent. For example, the reducing agent injection control valve 347 can control on-off that the reducing agent is injected through the reducing agent injecting section 600.

The reducing agent supply pressure confirming member 333 is installed on the reducing agent supply line 331 to check whether or not the reducing agent is normally supplied. That is, the reducing agent supply pressure confirming member 333 does not need to precisely detect the pressure of the reducing agent, and it is sufficient if the normal operation of the reducing agent supplying unit 310 can be confirmed. For example, as the reducing agent supply pressure confirming member 333, a pressure switch or a pressure sensor may be used.

The reducing agent pressure regulating valve 332 regulates the pressure of the reducing agent supplied through the reducing agent supply line 331. And a reducing agent pressure gauge for detecting the pressure of the reducing agent supplied through the reducing agent supply line 331 for setting the reducing agent pressure regulating valve 332. [ In addition, the first embodiment of the present invention is not limited to the above-described embodiment, and the reducing agent pressure gauge may be embedded in the reducing agent pressure regulating valve 332 without being separately formed.

The return line 336 branches at the reducing agent supply line 331 and returns a part of the reducing agent moving along the reducing agent supply line 331 to the reducing agent tank 830.

Further, for example, an additional reductant pressure regulating valve 337 may be provided on the return line 336. In this case, the pressure of the reducing agent supplied through the reducing agent supply line 331 can be kept constant by controlling the flow rate of the reducing agent, which is recovered through the return line 336, by the additional reducing agent pressure regulating valve 337. Of course, the additional reducing agent pressure regulating valve 337 may be omitted.

At least one reducing agent supply check valve 329 is installed in the reducing agent supply line 331 to prevent the reducing agent from flowing backward.

The reducing agent manual valve 334 may be installed in the reducing agent supply line 331 and may be operated by the user to open or close the emergency agent supply line 331 or use it as a safety device.

In the first embodiment of the present invention, the reducing agent supply unit 310 includes a reducing agent flow meter 343 for measuring the flow rate of the reducing agent to be supplied to the reducing agent spraying unit 600, a flow rate of the reducing agent supplied to the reducing agent spraying unit 600 And a reducing agent flow control valve 342 for controlling the flow rate of the reducing agent.

Specifically, the reducing agent flow meter 343 and the reducing agent flow control valve 342 supply the reducing agent spraying unit 600 with the reducing agent supplying unit 310 so that the reducing agent spraying unit 600 can spray the reducing agent to the target spraying amount It is used to control the flow rate of the reducing agent.

As described above, in the first embodiment of the present invention, the amount of the reducing agent supplied by the reducing agent supplying unit 310 and supplied by the reducing agent spraying unit 600 through the reducing agent flow meter 343 and the reducing agent flow control valve 342 . That is, according to the first embodiment of the present invention, it is possible to precisely control the amount of the reducing agent required for the selective catalytic reduction reaction and suppress the injection of the reducing agent more than necessary, thereby minimizing the occurrence of ammonia slip.

In the first embodiment of the present invention, the reducing agent flow meter 343 and the reducing agent flow rate control valve 342 are connected to each other through a connection between the reducing agent supply line 331 and the cleansing water supply line 361 of the cleansing water supply unit 360 And the reducing agent supply line 331 between the point and the reducing agent supply manifold 350. [ In this case, the cleansing water supply unit 360, which will be described later, inflows the cleansing water into the reducing agent supply line 331 through the cleansing water supply line 361 to remove the cleansing water from the reducing agent supply line 331 and the reducing agent spraying unit 600 The washing water can be remained in one area of the reducing agent supply line 331 provided with the reducing agent flow meter 343 and the reducing agent flow control valve 342. [ Therefore, it is possible to prevent the reducing agent flowmeter 343 and the reducing agent supply line 331 provided with the reducing agent flow control valve 342 from rushing, so that the reducing agent flowmeter 343 installed to control the supply flow rate of the reducing agent, Can be prevented.

On the other hand, unlike the first embodiment of the present invention, after the reducing agent supply line 331 and the reducing agent spraying unit 600 are cleaned, when the reducing agent supply line 331 provided with the reducing agent flow meter 343 becomes empty, The flow meter 343 malfunctions and it is difficult to measure the accurate flow rate.

The cleansing water supply unit 360 supplies cleansing water to the reducing agent supply line 331 and a reducing agent spraying unit 600 to be described later. The washing water supplied from the washing water supply unit 360 is used to remove the reducing agent remaining in the reducing agent supply line 331 or the reducing agent spraying unit 600 after the supply of the reducing agent to the reducing agent spraying unit 600 is stopped. At this time, the rinse water supply unit 360 can supply the rinse water stored in the rinse water tank 860. Here, the washing water tank 860 may be separately provided outside the reducing agent dosing module 300. However, the first embodiment of the present invention is not limited to the above, and the washing water tank 860 may also be included in the reducing agent dosing module 500.

Specifically, the washing water supply unit 360 includes a washing water supply line 361, a washing water control valve 365, a washing water pressure confirming member 363, a washing water pressure adjusting valve 362, 369, and a rinse water pass valve 364.

The washing water supply line 361 is connected to the reducing agent supply line 331. The washing water pressure confirming member 363 is installed in the washing water supply line 361 to check whether or not the washing water is normally supplied. As an example, a pressure switch or a pressure sensor may be used as the rinse water pressure confirming member 363.

The rinse water control valve 365 is provided in the rinse water supply line 361 to control whether the rinse water supplied by the rinse water supply unit 360 is supplied or not. For example, the rinse water control valve 365 can control on-off that the rinse water is supplied to the reducing agent supply line 331 through the rinse water supply line 361.

The rinse water pressure regulating valve 362 regulates the pressure of the rinse water supplied through the rinse water supply line 361. And a rinse water pressure gauge for detecting the pressure of the rinse water supplied through the rinse water supply line 361 for setting the rinse water pressure regulating valve 362. [ In addition, the first embodiment of the present invention is not limited to the above, and the washing water pressure gauge may be built in the washing water pressure regulating valve 362 without being separately formed.

The rinse water manual valve 364 may be installed in the rinse water supply line 361 and may be operated by a user to open or close the rinse water supply line 361 or to use it as a safety device.

One or more rinse water check valves 369 are provided in the rinse water supply line 361 to prevent the rinse water from flowing backward.

The compressed air reducing agent connecting unit 380 receives the compressed air from the integrated compressed air supplying apparatus 500 to be described later and transfers the compressed air to the reducing agent supplying line 331 and the reducing agent spraying unit 600 of the reducing agent supplying unit 310.

The compressed air delivered by the compressed air reducing agent connection unit 380 may be used for atomizing the reducing agent injected from the compressed air injecting unit 600 or for washing the reducing agent supplying line 331 and the reducing agent injecting unit 600.

Specifically, the compressed air reducing agent connection 380 includes a compressed air reductant connecting line 381, a compressed air control valve 385, a purge fine 386, a purge control valve 387, an air supply pressure confirming member 383, Air pressure regulating valve 382, compressed air supply manifold 390, compressed air drain line 395, compressed air drain valve 397, compressed air check valve 389, .

The compressed air reducing agent connecting line 381 connects the integrated compressed air supplying apparatus 500 and the reducing agent spraying unit 600, which will be described later. The purge line 386 connects the compressed air reducing agent connecting line 381 and the reducing agent supplying line 331. The reducing agent remaining in the reducing agent supply line 331 and the reducing agent spraying unit 600 can be removed by the purge line 386 using the compressed air supplied by the integrated compressed air supplying apparatus 500.

The connection point between the purge line 386 and the reducing agent supply line 331 is connected between the connecting point between the washing water supply line 361 and the reducing agent supply line 331 and between the reducing agent spraying unit 600 Lt; / RTI >

The compressed air supply manifold 390 is used to uniformly distribute the compressed air delivered through the compressed air reducing agent connecting line 381 when a reducing agent spraying unit 600 to be described later uses a plurality of nozzles.

The air injection control valve 385 is installed in the compressed air reducing agent connecting line 381 to control whether or not the reducing agent spraying unit 600 injects compressed air. For example, the air injection control valve 385 can control on-off that the compressed air is supplied to the reducing agent spraying unit 600 through the compressed air reducing agent connecting line 381.

A purge control valve 387 is provided in the purge line 386 to control the flow of compressed air moving through the purge line 386. In one example, the purge control valve 387 can control on-off that compressed air is supplied to the reducing agent supply line 386 through the purge line 386.

The air supply pressure confirming member 383 is installed in the compressed air reducing agent connecting line 381 to confirm whether or not the compressed air is normally supplied. That is, the air supply pressure confirming member 383 does not need to precisely detect the pressure of the compressed air, and it is sufficient if the normal operation of the integrated compressed air supplying apparatus 500 can be confirmed. As an example, a pressure switch or a pressure sensor may be used as the air supply pressure confirming member 383.

The air pressure regulating valve 382 regulates the pressure of the compressed air supplied through the compressed air reducing agent connecting line 381. That is, the air pressure regulating valve 382 regulates the pressure of the compressed air supplied to the reducing agent spraying unit 600. And an air pressure gauge for detecting the pressure of the compressed air supplied through the compressed air reducing agent connecting line 381 for setting the air pressure regulating valve 382. [ In addition, the first embodiment of the present invention is not limited to the above-described embodiment, and the air pressure gauge may be built in the air pressure regulating valve 382 without being separately formed.

The compressed air drain line 395 is connected to the lower portion of the compressed air supply manifold 390 to drain foreign matter remaining in the compressed air supply manifold 950 if necessary. And a compressed air drain valve 397 is provided on the compressed air drain line 395 to open and close the compressed air drain line 395. [

The compressed air passageway 384 may be installed in the compressed air reductant connection line 381 and may be operated by a user to open or close the compressed air reductant connection line 381 in an emergency or utilize it as a safety device.

The compressed air check valve 389 is installed in the compressed air reducing agent connecting line 381 and the purge line 386 to prevent backflow of compressed air.

The second support frame 305 supports the reducing agent supply unit 310, the cleaning water supply unit 360, and the compressed air reducing agent connection unit 380. The second support frame 305 is formed in a block shape of various shapes and may be detachably engaged with the first support frame 205 as shown in FIGS.

Therefore, the reducing agent dosing module 300 can be manufactured in various shapes according to the installation space, and can be easily combined with or separated from the burner supply module 200.

The reducing agent spraying unit 600 injects the reducing agent supplied by the reducing agent supplying unit 310 as shown in FIG. The reducing agent spraying unit 600 may use a plurality of nozzles. However, the first embodiment of the present invention is not limited thereto, and the reducing agent spraying unit 600 may use one nozzle.

In addition, for example, the reducing agent spraying unit 600 may be installed on the exhaust flow path. That is, the reducing agent spraying unit 600 can spray the reducing agent to the exhaust gas moving along the exhaust flow path.

However, the first embodiment of the present invention is not limited thereto. That is, the selective catalytic reduction system 101 may further include a separate decomposition chamber or an evaporator for decomposing the reducing agent. The reducing agent spraying unit 600 may be installed in the decomposition chamber or the evaporator to inject the reducing agent into the decomposition chamber or the evaporator. In some cases, the reducing agent spraying unit 600 may spray the reducing agent directly in the reactor provided with the catalyst for the selective catalytic reduction reaction.

In the first embodiment of the present invention, urea (CO (NH ₂ ) ₂ ) may be used as a reducing agent supplied from the reducing agent supplying unit 310 and injected from the reducing agent injecting unit 600. The reducing agent of urea _{(urea, CO (NH 2)} 2) is decomposed pyrolysis or hydrolysis produces ammonia (NH ₃₎ to reduce nitrogen oxides (NOx). More specifically, when the urea (urea, CO (NH _{2) 2)} injected through the reducing agent injection assembly 600 is disassembled, when isobutane with ammonia (NH ₃₎ is generated Ansan (Isocyanic acid, HNCO). And isocyanate is decomposed again and becomes ammonia. That is, the urea is decomposed and finally ammonia can be produced.

The integrated compressed air supply apparatus 500 supplies compressed air to the fuel injection unit 470 of the burner 400 through the compressed air burner connection line 241 of the burner supply module 200 and supplies the compressed air to the reducing agent dosing module 300, The compressed air is supplied to the reducing agent supplying unit 310 and the reducing agent spraying unit 600 through the compressed air reducing agent connecting line 381 of FIG.

Specifically, the integrated compressed air supply apparatus 500 supplies the compressed air necessary for atomizing the fuel to be injected by the fuel injecting section 470 of the burner 400, atomizes the reducing agent to be injected by the reducing agent injecting section 600, Or supply the compressed air necessary for cleaning the reducing agent supply part 310 and the reducing agent spray part 600. [

In the first embodiment of the present invention, the compressed air supplied by the integrated compressed air supply device 500 can be designed to have a diameter and a shape of a pipe for supplying compressed air so that the flow velocity is 25 m / s or less.

The engaging member 701 engages the first support frame 205 and the second support frame 305, as shown in Figs. 4 and 5.

In the first embodiment of the present invention, the engaging member 701 may be an engaging pin which is fitted in a state where a part of the first supporting frame 205 and a part of the second supporting frame 305 are engaged.

Accordingly, the burner supply module 200 and the reducing agent dosing module 300 can be easily joined or separated from each other.

As described above, according to the first embodiment of the present invention, the compressed air supplied to the modularized burner supply module 200 and the reducing agent dosing module 300 can be integrally managed.

Particularly, according to the first embodiment of the present invention, the integrated compressed air supply apparatus 500 can reduce the pressure or the flow rate of the compressed air to be finally supplied to the reducing agent spraying unit 600 and the fuel spraying unit 470, Can be adjusted.

More specifically, as the load is lowered on the basis of when the load of the engine is the maximum load, the integrated compressed air supply apparatus 500 causes the compressed air supplied from the fuel injecting section 470 to atomize the fuel to be injected and the reducing agent injecting section 600 can reduce the pressure or the flow rate of the compressed air supplied to atomize the reducing agent to be sprayed, respectively.

Since the temperature of the exhaust gas varies depending on the load of the engine, the degree of operation of the burner 400 for raising the exhaust gas may also vary depending on the load of the engine. That is, the amount of fuel supplied to the burner 400 also depends on the load of the engine.

Therefore, when the compressed air used to atomize the injected fuel is always supplied at a constant pressure, the fuel may not be atomized to an appropriate size or the fuel may be injected irregularly. Specifically, if the fuel is injected in excess of the appropriate fuel injection amount to the pressure of the compressed air, atomization of the injected fuel may not be sufficient. On the other hand, if the injection amount of the fuel is significantly lower than the pressure of the compressed air, irregular injection phenomenon in which the fuel is not injected instantaneously or intermittently by the pressure of the compressed air may occur.

However, according to the first embodiment of the present invention, the pressure or the flow rate of the compressed air to be supplied to the fuel injecting section 470 can be adjusted according to the load variation of the engine. Therefore, compressed air can be appropriately supplied in accordance with the fuel supply amount.

Also, the concentration of nitrogen oxide contained in the exhaust gas varies depending on the load of the engine. Therefore, the amount of the reducing agent required for the selective catalytic reduction reaction for reducing the nitrogen oxides contained in the exhaust gas varies depending on the load of the engine. That is, when the load of the engine is lowered, the concentration of the nitrogen oxide contained in the exhaust gas is also lowered. Therefore, in the first embodiment of the present invention, as the load becomes lower on the basis of the maximum load of the engine, 500 also reduces the pressure or the flow rate of the compressed air supplied to the reducing agent spraying unit 600.

More specifically, the reducing agent supply unit 310 precisely controls the reducing agent flow meter 343 and the reducing agent flow rate control valve 342 to inject the reducing agent as needed through the reducing agent spray unit 600 according to the engine load variation . As a result, unnecessary reducing agent is injected, so that generation of ammonia slip can be suppressed.

As described above, according to the first embodiment of the present invention, when the amount of the reducing agent supplied varies according to the operating conditions of the engine, the pressure of the compressed air used for spraying and atomizing the reducing agent can be adjusted in conjunction with the variation in the amount of the reducing agent supplied .

Therefore, it is possible to prevent a phenomenon that the size of the reducing agent injection particles varies depending on the operation conditions of the engine depending on the amount of the reducing agent supplied.

In addition, when the pressure of the reducing agent is higher than the pressure of the compressed air, if the reducing agent is injected and the pressure of the reducing agent is lower than the pressure of the compressed air, irregular injection phenomenon that the reducing agent is not sprayed is prevented, Can regularly and uniformly inject the reducing agent.

In the first embodiment of the present invention, as the load of the engine increases and the amount of the reducing agent supplied increases, the supply pressure of the compressed air also increases proportionally. When the load of the engine decreases and the amount of the reducing agent decreases, The supply pressure of the compressed air can also be reduced.

For this purpose, the air pressure regulating valve 382 may be an electronic proportional pressure reducing valve (EPPRV).

Further, in the first embodiment of the present invention, the load of the engine can be calculated through one of the rotational speed of the engine, the rotational speed of the supercharger mounted on the engine, or the scavenging pressure supplied to the engine.

This is because the rotation speed of the engine, the scavenging pressure, and the rotation speed of the supercharger increase or decrease in proportion to the load of the engine. Therefore, in addition to the rotational speed of the engine, the rotational speed of the turbocharger mounted on the engine, or the desired pressure supplied to the engine, the load of the engine may be calculated on the basis of other factors that increase or decrease in accordance with the load fluctuation of the engine.

Hereinafter, the operation principle of the reducing agent dosing module 300 in the selective catalytic reduction system 101 according to the first embodiment of the present invention will be described in detail.

When the selective catalytic reduction system 101 starts operating, the reducing agent dosing module 300 receives compressed air from the integrated compressed air supply device 500.

At this time, the pressure of the compressed air is detected through the air supply pressure confirming member 383. At this time, if the pressure of the compressed air is not detected, the integrated compressed air supply apparatus 500 may be checked and then the integrated compressed air supply apparatus 00 may be restarted. When the pressure of the compressed air is detected, the reducing agent supply unit 310 is operated.

When the reducing agent supply unit 310 is operated, the reducing agent supply pressure is detected through the reducing agent supply pressure confirming member 333. At this time, if the reducing agent supply pressure is not detected, the reducing agent supplying unit 310 can be restarted after the reducing agent supplying unit 310 is checked. When the reducing agent supply pressure is detected, the reducing agent spraying unit 600 starts spraying the reducing agent. At this time, the reducing agent injection can be started by opening the reducing agent injection control valve 347.

When the load of the engine fluctuates after the start of the injection of the reducing agent, the reducing agent supply unit 310 adjusts the amount of the reducing agent supplied according to the load variation of the engine. The air pressure regulating valve 382 is controlled according to the engine load variation to regulate the pressure of the compressed air supplied to the reducing agent spraying unit 600 in proportion to the load of the engine. The load of the engine and the supply amount of the reducing agent are proportional to each other, so that the pressure of the compressed air can be adjusted in conjunction with the fluctuation of the reducing agent supply amount.

Thus, the pressure of the compressed air supplied from the integrated compressed air supply device 500 to the reducing agent spraying unit 600 through the reducing agent dosing module 300 is adjusted in accordance with the load variation of the engine.

Thereafter, when the injection of the reducing agent is terminated or when the clogging of the reducing agent injecting unit 600 is detected, the reducing agent injection is stopped. Then, the reducing agent may be injected again after removing the reducing agent or foreign matter remaining in the reducing agent supplying line 331 and the reducing agent injecting unit 600 or solving the clogging of the reducing agent injecting unit 600 by performing purge .

With such a structure, the selective catalytic reduction system 101 according to the first embodiment of the present invention can realize modularization for each field in order to simplify the overall structure and to facilitate maintenance.

In addition, according to the first embodiment of the present invention, the selective catalytic reduction system 101 can integrally control the supply of compressed air used for various purposes in various fields.

Further, according to the first embodiment of the present invention, the selective catalytic reduction system 101 can appropriately supply as much compressed air as necessary in accordance with the load fluctuation of the engine.

Therefore, the fuel injected from the fuel injecting unit 470 of the burner 400 can be effectively atomized, and the reducing agent injected from the reducing agent injecting unit 600 can be effectively atomized.

Also, since the pressure of the compressed air is adjusted according to the variation of the amount of the reducing agent, when the amount of the reducing agent injected increases, the pressure of the compressed air also increases, and the size of the injected particles of the reducing agent injected from the reducing agent injecting unit 600 can be maintained constant. That is, the width of the lower limit and the upper limit of the reducing agent injection flow rate that are effectively sprayed by the reducing agent spraying unit 600 can be widened.

A modification of the first embodiment of the present invention will be described below.

6, according to a modification of the first embodiment of the present invention, the pressure of the compressed air according to the load variation of the engine is mapped and the compressed air supplied from the integrated compressed air supply apparatus 500 Can be controlled step by step.

However, the modification of the first embodiment of the present invention is not limited to the above-described one, and it is also possible to linearly control the pressure of the compressed air supplied by the integrated compressed air supply apparatus 500 in proportion to the load variation of the engine .

As described above, according to the modification of the first embodiment of the present invention, the integrated compressed air supply apparatus 500 is capable of controlling the pressure or flow rate of the compressed air required for each load of the engine, The pressure or the flow rate of the compressed air supplied to the burner 400 through the burner supply module 200 and the compressed air supplied to the reducing agent spraying unit 600 through the reducing agent dosing module 300 can be adjusted.

Hereinafter, a second embodiment of the present invention will be described with reference to Figs. 6 to 8. Fig.

6, in the selective catalytic reduction system 102 according to the second embodiment of the present invention, the first supporting frame 205 of the burner supplying module 200 and the second supporting frame 205 of the reducing agent dosing module 300 The frame 305 is rotatably coupled with one region.

The coupling member 702 may include a hinge that pivotally connects one area of the first support frame 205 and one area of the second support frame 305. [

In addition, another area of the first support frame 205 and another area of the second support frame 305 may be detachably coupled to each other through another engaging member 703. [ At this time, the other engagement member 703 may include a cicada ring.

With this structure, the selective catalytic reduction system 102 according to the second embodiment of the present invention can easily couple or separate the first support frame 205 and a part of the second support frame 305. Thus, the selective catalytic reduction system 102 can be effectively maintained.

In addition, the present invention can be variously modified in combination with the above-described first and second embodiments. For example, the coupling pins and hinges may be used in combination with the coupling members 701, 702, 703, or only the cimmerian rings may be used.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. will be.

It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

101, 102: selective catalytic reduction system
200: Burner supply module
220: fuel supply unit
240: Compressed air burner connection
241: Compressed air burner connection line
242: Compressed Air Burner Connection Valve
280: Blower
300: Reducing agent dosing module
310: Reducing agent supply unit
320: Reducing agent feed pump
326: Pressure gauge for reductant feed pump
327: Valve for reductant feed pump
328: Filter
329: Reducing agent supply check valve
331: Reducing agent supply line
332: Reducing agent pressure regulating valve
333: absence of reductant supply pressure check member
334: Reducing agent supply manual valve
336: return line
337: Additional reducing agent pressure regulating valve
338: Return valve
342: Reducing agent flow control valve
343: Reducing agent flowmeter
347: Reducing agent injection control valve
350: Reducing agent supply manifold
355: Reductant drain line
357: Reducing agent drain valve
360: Cleaning water supply part
361: Cleaning water supply line
362: Wash water pressure regulating valve
363: washing water pressure confirmation member
364: and rinse water manual valve
365: Clean water control valve
369: Wash water check valve
380: Compressed air reducing agent connection part
381: Compressed air reducing agent connection line
382: Air pressure regulating valve
383: Air supply pressure check member
384: Compressed air manual valve
385: Compressed air control valve
386: Fuzzy Pine
387: Purge control valve
389: Compressed air check valve
390: Compressed air supply manifold
395: Compressed air drain line
397: Compressed air drain valve
400: Burner
410: burner body
470: fuel injection part
500: Integrated compressed air supply
600: Reducing agent dispenser
701, 702, 703:
820: Fuel tank
830: Reducing agent tank
860: Cleaning water tank

Claims (18)

A burner supply module including a fuel supply part for supplying fuel and a first support frame formed in a block shape to support the fuel supply part;
A reducing agent supplying unit for supplying a reducing agent for reducing nitrogen oxides; a reducing agent dosing module including a second supporting frame formed in a block shape supporting the reducing agent supplying unit and detachably coupled to the first supporting frame; And
An integrated compressed air supply device for supplying compressed air to the fuel injection part of the burner supply module and the reducing agent supply part of the reducing agent dosing module,
≪ / RTI > The method according to claim 1,
Further comprising a burner for supplying fuel from the fuel supply portion of the burner supply module,
Characterized in that the burner includes a burner main body and a fuel injection part 3. The method of claim 2,
And a reducing agent injecting unit injecting the reducing agent supplied by the reducing agent supplying unit. The method of claim 3,
Wherein the reducing agent supply unit includes a reducing agent flow meter for measuring a flow rate of the reducing agent to be supplied to the reducing agent spraying unit and a reducing agent flow rate control valve for controlling a flow rate of the reducing agent supplied to the reducing agent spraying unit. The method of claim 3,
Wherein the burner supply module further comprises a compressed air burner connection portion that receives compressed air from the integrated compressed air supply device and transfers the compressed air to the burner and is supported by the first support frame,
The reducing agent dosing module may further include a compressed air reducing agent connecting part which receives compressed air from the integrated compressed air supplying device and transfers the compressed air to the reducing agent supplying line and the reducing agent spraying part of the reducing agent supplying part and is supported by the second supporting frame ≪ / RTI > 6. The method of claim 5,
The integrated compressed air supply device supplies compressed air necessary for atomizing the fuel to be injected by the fuel injecting section of the burner, atomizes the reducing agent to be injected by the reducing agent injecting section, or cleans the reducing agent injecting section and the reducing agent supplying section And the compressed air is supplied to the selective catalytic reduction system. 3. The method of claim 2,
Wherein the burner supply module further comprises a blower for supplying combustion air to the burner and supported inside the first support frame. The method of claim 3,
Wherein the reducing agent dosing module further comprises a washing water supply unit that supplies washing water to the reducing agent supplying unit and the reducing agent spraying unit and is supported inside the second supporting frame. 9. The method of claim 8,
A fuel tank for storing fuel to be supplied by the fuel supply unit;
A reducing agent tank for storing a reducing agent to be supplied to the reducing agent supplying unit; And
A cleaning water tank for storing cleaning water to be supplied by the cleaning water supply unit;
Further comprising a catalytic reduction catalyst. 6. The method of claim 5,
The selective catalytic reduction system described above reduces nitrogen oxides contained in the exhaust gas discharged from an engine having a variable load,
The integrated compressed air supply device adjusts the pressure or the flow rate of the compressed air supplied to the reducing agent spraying unit via the reducing agent dosing module and the compressed air supplied to the burner through the burner supply module in accordance with the load variation of the engine Wherein the selective catalytic reduction system comprises: 11. The method of claim 10,
As the load is lowered on the basis of when the load of the engine is the maximum load, the integrated compressed air supply apparatus is configured to reduce the compressed air supplied by the fuel injection unit to atomize the fuel to be injected and the reducing agent to be injected by the reducing agent injection unit And the pressure or flow rate of the compressed air to be supplied is respectively reduced. 11. The method of claim 10,
Wherein the compressed air supply device supplies the compressed air supplied from the compressed air supply source to the reducing agent spraying unit and the fuel spraying unit, Wherein the pressure or flow rate of the selective catalytic reduction system is controlled. 11. The method of claim 10,
And an electronic proportional pressure reducing valve (EPPRV). 11. The method of claim 10,
Wherein the load of the engine is calculated through one of the rotational speed of the engine, the rotational speed of the turbocharger mounted on the engine, or the desired pressure supplied to the engine. 15. The method according to any one of claims 1 to 14,
Further comprising a coupling member for coupling the first support frame and the second support frame to each other. 16. The method of claim 15,
Wherein the engaging member includes an engaging pin that is engaged with a part of the first support frame and a part of the second support frame. 16. The method of claim 15,
Wherein the engaging member includes a hinge that pivotally connects one area of the first support frame and one area of the second support frame. 16. The method of claim 15,
Wherein said coupling member comprises a cicada ring.

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