KR101357915B1 - Internal combustion engine - Google Patents

Abstract

The present invention has at least one stage exhaust gas turbocharge system by at least one exhaust gas turbocharger (11, 24) and an exhaust gas purification system by particle filter (14) and SCR catalyst (15), and metering in reducing agent A hydrolysis catalyst 17 located in the exhaust gas bypass line 18 together with the device 16, wherein exhaust gas flow through the exhaust gas bypass line 18 can be regulated by the regulating device 19. Internal combustion engines, in particular marine diesel internal combustion engines operating with heavy oil, wherein the exhaust gas bypass line (18), on which the reducing agent metering device (16) and the hydrolysis catalyst (17) are located, has at least a particulate filter (14). ), So that exhaust gas can be directed towards the SCR catalyst 15 at least by bypassing the particle filter 14 via the exhaust gas bypass line 18.

Description

Internal combustion engine {INTERNAL COMBUSTION ENGINE}

The present invention relates to an internal combustion engine according to the preamble of claim 1.

From DE 10 2004 027 593 A1 an internal combustion engine having a single or two stage exhaust gas turbocharge system and an exhaust gas purification system with an SCR catalyst is known. According to the prior art, in the case of a single stage exhaust gas turbocharge system, the SCR catalyst is located downstream of the turbine of the exhaust gas turbocharger or upstream of the turbine of the exhaust gas turbocharger. Further, according to the prior art, in the case of a two stage exhaust gas turbocharge system with two exhaust gas turbochargers, the SCR catalyst is interposed or located between two turbines of both exhaust gas turbochargers. It is also already known from the prior art to bypass the SCR catalyst via a bypass line in order to lead the exhaust gas past the SCR catalyst and towards the turbine of the exhaust gas turbocharger located downstream of the SCR catalyst. The exhaust gas flow through such bypass lines can be regulated by the regulating device.

Another internal combustion engine is known from DE 10 2007 061 005 A1. The internal combustion engine according to the prior art also has an exhaust gas turbocharger in which the exhaust gas passing through the turbine of the exhaust gas turbocharger is then passed through an oxidation catalyst, through a particle filter behind the oxidation catalyst, followed by an SCR catalyst. And through another oxidation catalyst behind the SCR catalyst. The exhaust gas is directed through the exhaust gas bypass line, where the reducing agent dosing device and the hydrolysis catalyst are located, through the turbine of the exhaust turbocharger and the oxidation catalyst disposed behind the turbine to the particle filter. It is also known from the prior art that can be.

The problem of this invention starting from that is to provide a novel internal combustion engine.

Such a problem is solved by an internal combustion engine according to claim 1. According to the invention, an exhaust gas bypass line in which a reducing agent metering device and a hydrolysis catalyst are located is guided around at least the particle filter, whereby the exhaust gas bypasses at least the particle filter through the exhaust gas bypass line and is directed towards the SCR catalyst. Can be.

The invention proposes for the first time an internal combustion engine in which an exhaust gas bypass line in which a reducing agent metering device and a hydrolysis catalyst are located is guided around at least a particle filter. The exhaust gas thus guided through the exhaust gas bypass line and thus through the reducing agent metering device and the hydrolysis catalyst can be directed towards the SCR catalyst at least past the particle filter. As a result, the efficiency of the SCR catalyst can be increased. In addition, the counter pressure on the exhaust gas stream, produced by the particle filter, facilitates branching of the exhaust gas through an exhaust gas bypass line in which the reducing agent metering device and the hydrolysis catalyst are located.

Another exhaust gas bypass line allows the exhaust gas to be directed towards the SCR catalyst on the one hand at least by bypassing the particle filter and on the other hand by the reducing agent metering unit and the hydrolysis catalyst, while another exhaust gas bypass line is Preferably, the exhaust gas flow through can be regulated by another control device. Further increase in the efficiency of the SCR catalyst can be realized by at least by bypassing the particle filter as well as by means of another exhaust gas bypass line which allows to bypass the reducing agent metering device and the hydrolysis catalyst.

According to a further preferred configuration of the present invention, starting from the compressor of each exhaust gas turbocharger, the charge air is passed through the boost air bypass line to the exhaust gas bypass line where the reducing agent metering device and the hydrolysis catalyst are located, ie reducing agent metering. May be fed upstream of the apparatus and the hydrolysis catalyst. With such supercharged air delivered through the supercharged air bypass line, the exhaust gas delivered through the reducer metering device and the exhaust gas bypass line in which the hydrolysis catalyst is located is mixed with the supernatant air and through the reducing agent metering device and the hydrolysis catalyst It is possible to precisely control the temperature of the exhaust gases to be delivered, thereby increasing the efficiency of the reducing agent metering device and the hydrolysis catalyst and thus the efficiency of the SCR catalyst.

In the internal combustion engine according to the present invention, the exhaust gas bypass line in which the reducing agent metering device and the hydrolysis catalyst are located is guided around at least the particle filter, so that the exhaust gas guided through the exhaust gas bypass line passes at least the particle filter and the SCR. Can be directed towards the catalyst, thereby increasing the efficiency of the SCR catalyst. In addition, the efficiency of the SCR catalyst can be further increased by another exhaust gas bypass line that allows bypass of the particle filter as well as the reducing agent metering device and the hydrolysis catalyst.

1 shows schematically a supercharged internal combustion engine according to a first embodiment of the invention;
2 is a schematic representation of a turbocharged internal combustion engine according to a second embodiment of the invention;
3 schematically shows a turbocharged internal combustion engine according to a third embodiment of the invention;
4 schematically shows a turbocharged internal combustion engine according to a fourth embodiment of the invention;
5 is a schematic representation of a turbocharged internal combustion engine according to a fifth embodiment of the invention;
6 is a schematic representation of a turbocharged internal combustion engine according to a sixth embodiment of the invention;
7 is a schematic illustration of a turbocharged internal combustion engine according to a seventh embodiment of the invention;
8 is a schematic illustration of a turbocharged internal combustion engine according to an eighth embodiment of the invention;
9 is a schematic illustration of a turbocharged internal combustion engine according to a ninth embodiment of the invention;
10 is a schematic illustration of a turbocharged internal combustion engine according to a tenth embodiment of the invention;

The preferred additional configurations of the invention will become apparent from the dependent claims and the description below. Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings without limiting the invention thereto.

The present invention relates to an internal combustion engine, in particular a marine diesel internal combustion engine operated with heavy oil. Marine diesel internal combustion engines operating on heavy oil have the specificity that their fuel, ie heavy oil, has a relatively high sulfur content. Undesired reactions of sulfur oxides with ammonia can result in deposits that impair the efficiency of exhaust gas purification. In particular, such unwanted reactions occur in conjunction with low temperatures. In an internal combustion engine according to the invention it can be avoided.

FIG. 1 shows an embodiment of an internal combustion engine 10 having a one-stage exhaust gas supercharging system by means of an exhaust gas turbocharger 11, wherein a turbine 12 and a compressor 13 of the exhaust gas turbocharger 11 are shown. Is shown. The exhaust gas leaving the internal combustion engine is guided through the turbine 12 of the exhaust gas turbocharger 11 and depressurized in the turbine 12 where the energy obtained is compressed to compress the boost air to be supplied to the internal combustion engine 10. (13) is used to drive. The internal combustion engine 10 shown in FIG. 1 also has a particle filter 14 and an SCR catalyst 15 in the exhaust gas stream, in which the particle filter 14 is arranged downstream of the turbine 12, The SCR catalyst 15 is disposed downstream of the particle filter 14.

In addition, the internal combustion engine of FIG. 1 has a reducing agent metering device 16 and a hydrolysis catalyst 17 disposed in the exhaust gas bypass line 18, in the sense of the present invention reducing agent metering device 16 and hydrolysis. The exhaust gas bypass line 18 in which the catalyst 17 is located is guided at least around the particle filter 14 and thus through the exhaust gas bypass line and thus the reducing agent metering device 16 and the hydrolysis catalyst 17 Exhaust gas, which is directed through N, may bypass the particulate filter 14 and be directed towards the SCR catalyst 15. The exhaust gas flow through the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located can be regulated by the regulating device 19.

The hydrolysis catalyst 17 located in the exhaust gas bypass line 8 produces an effective vaporization and is introduced by the reducing agent metering device 16 into the exhaust gas flow directed through the exhaust gas bypass line 18. Accelerating the conversion of the reducing agent for the SCR exhaust gas purification in the catalyst 15, so that the effective operation of the SCR catalyst 15 can be ensured. By placing the reducing agent metering device 16 and the hydrolysis catalyst 17 in the exhaust gas bypass line 18 bypassing the particle filter 14, the particle filter 14 is placed upstream of the particle filter 14. Blockages are prevented due to the metered supply of the reducing agent and by the sediment. Therefore, according to the present invention, the efficiency of the particle filter 14 and the SCR catalyst 15 can be increased.

2 shows that the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located is guided around the particle filter 14, as well as the turbine 12 of the exhaust gas turbocharger 11. The configuration of the internal combustion engine according to the present invention, which is also guided through). Therefore, the exhaust gas is delivered not only through the turbine 12 of the exhaust gas turbocharger 11 but also through the particle filter 14, introducing a reducing agent into the exhaust gas delivered through the exhaust gas bypass line 18, and hydrolysis. It can be guided through catalyst 17 and then to the SCR catalyst.

In the remaining details, since the embodiment of FIG. 2 is the same as the embodiment of FIG. 1, the description of the embodiment of FIG. 1 may be referred to.

3 shows another exhaust gas bypass line 20 in addition to the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located, and another exhaust gas bypass line ( 20 through the exhaust gas is directed to the SCR catalyst 15 on the one hand bypassing the turbine 12 and the particle filter 14 and on the other hand bypassing the reducing agent metering device 16 and the hydrolysis catalyst 17. A further configuration of the embodiment of FIG. 2 is shown. The exhaust gas flow through such another exhaust gas bypass line 20 can be regulated by another regulator 21. By precisely adjusting the exhaust gas volume flow rates and temperatures by both exhaust gas bypass lines 18, 20, the efficiency of exhaust gas purification can be further increased. The exhaust gas bypass line 20 of FIG. 3 can also be used in the embodiment of FIG. 1, in which case the exhaust gas bypass line 20 is connected in parallel with the exhaust gas bypass line 18, and only particles Bypass only the filter 14.

FIG. 4 shows yet another further configuration of the embodiment of FIG. 2, where in the embodiment of FIG. 4 the charge air starts from the compressor 13, ie downstream of the compressor 13 in FIG. 4 and the internal combustion engine ( Starting from upstream of 10) via the supercharged air bypass line 22 to the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located, ie the reducing agent metering device according to FIG. Upstream of (16) and upstream of the hydrolysis catalyst (17). The boost air flow through such boost air bypass line 22 can be regulated by the regulator 23. As such, by incorporating the charge air into the exhaust gas that is passed through the particle filter 14 through the exhaust gas bypass line 18, the temperature of the exhaust gas that is delivered through the exhaust gas bypass line 18 is at a desired level. Can be adjusted accurately. Thereby, it is further possible to increase the efficiency in the area of the SCR catalyst 15 and thus increase the efficiency of exhaust gas purification. You also get the option to use the charge air as metered air.

FIG. 5 combines the embodiments of FIGS. 3 and 4 with each other, ie another exhaust gas bypass line 20 with its respective regulating devices 21, 23 as well as the supercharged air bypass line 22. An embodiment of the present invention is also illustrated. Such a combination is highly desirable to increase the efficiency of the SCR catalyst 15, where it should be noted that the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located is solely the particle filter 14. The same combination of another exhaust gas bypass line 20 and the supercharged air bypass line 22 also applies to the embodiment of FIG. 1, which does not bypass the turbine 12 of the exhaust gas turbocharger 11. Is to apply the intended use.

FIG. 6 is a further configuration of the internal combustion engine 10 of FIG. 1, in which a boost air bypass line 22 having the regulating device 23 is provided to provide an exhaust gas bypass line upstream of the reducing agent metering device 16. 18 shows an embodiment of supplying boost air. In the present embodiment, unlike the embodiments of FIGS. 4 and 5, the boost air is not exhaust downstream of the compressor 13 of the exhaust gas turbocharger 11 as in the embodiments of FIGS. 4 and 5. Upstream of the compressor 13 of the turbocharger 11 it is directed through the supercharged air bypass line 22 towards the exhaust gas bypass line 18. However, in order to be able to simply feed the charge air to the exhaust gas bypass line 18, the types of FIGS. 4 and 5 in which the charge air is branched downstream of the compressor 13 are preferred.

1 to 6 are common in that each internal combustion engine has a single stage exhaust gas turbocharge system. On the other hand, FIGS. 7 to 10 show embodiments of an internal combustion engine having a multistage exhaust gas turbocharge system, ie a two stage exhaust gas turbocharge system, and thus in addition to the exhaust gas turbocharger 11 a turbine ( Another exhaust gas turbocharger 24 with a 25 and a compressor 25 is provided.

In that case, the turbine 12 of the exhaust gas turbocharger 11 is a high pressure turbine, and the turbine 25 of the exhaust gas turbocharger 24 is a low pressure turbine. Correspondingly, the compressor 13 of the exhaust gas turbocharger 11 is a high pressure compressor, and the compressor 26 of the exhaust gas turbocharger 24 is a low pressure compressor.

In the embodiments of FIGS. 7-9, the particle filter 14 and the SCR catalyst 15 are located between the two turbines 12, 25 of both exhaust gas turbochargers 11, 24. That is, the SCR catalyst 15 is again located downstream of the particle filter 14.

In the internal combustion engine of FIG. 7, the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located bypasses only the particle filter 14.

On the other hand, in FIG. 8, the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located serves as a high-pressure turbine as well as the particle filter 14. The turbine 12 of) is also bypassed. In FIG. 8, as in the embodiments of FIGS. 4 and 5, an exhaust gas turbocharger in which the boost air for regulating the exhaust gas delivered through the exhaust gas bypass line 18 to an appropriate temperature is operated as a high pressure compressor. It can be introduced into the exhaust gas bypass line 18 via the boost air bypass line 22 branched downstream of the compressor 13 of (11).

In the embodiment of FIG. 9, which shows a further configuration of the embodiment of FIG. 8, another exhaust gas bypass line 20 is further provided, through which the exhaust gas is pressurized. Turbine 12 and particle filter 14, as well as reducing agent metering device 16 and hydrolysis catalyst 17, may be directed past SCR catalyst 15.

Of course, the boost air bypass line 22 according to FIGS. 8 and 9 may be branched between or in front of the compressors.

FIG. 10 has a two stage exhaust gas turbocharge system with two exhaust gas turbochargers 11, 24, but unlike the embodiments of FIGS. 7 to 9, the particle filter 14 and its particle filter ( The SCR catalyst 15 connected behind 14 is not disposed between the two turbines 12, 25, but rather downstream of the turbine 25 of the exhaust gas turbocharger 24, which serves as a low pressure turbine. Another embodiment of an internal combustion engine 10 is shown. At this time, in FIG. 10, the exhaust gas bypass line 18 in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located again bypasses only the particle filter 14. Alternatively, however, it is also possible to configure the exhaust gas bypass line 18 to bypass the turbine 25 of the exhaust gas turbocharger 24. Also in FIG. 10 another exhaust gas bypass line 20 and a charge air bypass line 22 may be used, in which case the charge air bypass line 22 is downstream of the compressor 26 or in the compressor ( Also downstream of 13), the boost air can be branched and supplied to the exhaust gas bypass line 18, that is, upstream of the reducing agent metering device 16.

In all embodiments, the exhaust gas is passed through the particle filter 14 through the exhaust gas bypass line 18 to pass the exhaust gas passed through the particle filter 14 to the reducing agent metering device 16 and the hydrolysis catalyst ( It is common in that it is sent through 17) and then fed to the SCR catalyst 15. Thereby, the efficiency of exhaust gas purification can be increased. On the one hand, blockage of the exhaust gas particle filter 14 is avoided, and on the other hand, effective conversion of the reducing agent for SCR exhaust gas purification in the SCR catalyst 15 can be ensured.

By completely degrading the liquid reducing agent into the product in gaseous form in the bypass with optimized conditions accordingly, it is only then sent to the SCR catalyst, thereby reducing the risk of formation of exhaust gas deposits on the SCR catalyst in conjunction with heavy oil operation. It means that the minimum service temperature for the SCR catalyst in sulfur containing fuels can be lowered and the temperature window for SCR operation can be larger.

10: internal combustion engine 11, 24: exhaust gas turbocharger
12, 25 turbine 13, 26 compressor
14 particle filter 15 SCR catalyst
16: reducing agent meter 17: hydrolysis catalyst
18, 20: exhaust gas bypass lines 19, 21, 23: regulator
22: Supercharged Air Bypass Line

Claims (6)

Reducing agent metering device 16 having at least one stage exhaust gas turbocharge system by at least one exhaust gas turbocharger 11, 24 and an exhaust gas purification system by particle filter 14 and SCR catalyst 15. Together with a hydrolysis catalyst 17 located in the exhaust gas bypass line 18, wherein the exhaust gas flow through the exhaust gas bypass line 18 can be regulated by the regulating device 19. In
The exhaust gas bypass line 18, in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located, is guided around at least the particle filter 14, whereby the exhaust gas passes through the exhaust gas bypass line 18. May be directed towards the SCR catalyst 15 at least by bypassing the particle filter 14,
A charge air bypass line 22 is provided, through which the charge air starts from the compressor 13 of each exhaust gas turbocharger, reducing the metering device 16 and the hydrolysis catalyst. Internal combustion engines, which can be fed to an exhaust gas bypass line 18 in which 17 is located, wherein the boost air flow through the boost air bypass line 22 can be regulated by the regulating device 23. . 2. The turbine 12 of the exhaust gas turbocharger of claim 1, wherein the exhaust gas bypass line 18, in which the reducing agent metering device 16 and the hydrolysis catalyst 17 are located, is guided around the particle filter 14 as well. It is also shown around, whereby exhaust gas can be directed to the SCR catalyst 15 by bypassing the turbine 12 and the particle filter 14 of each exhaust turbocharger via an exhaust gas bypass line 18. An internal combustion engine, characterized in that. A further exhaust gas bypass line (20) is provided, through which another exhaust gas bypass line (20) bypasses the particulate filter (14) on the one hand. And on the other hand, it can be diverted to the SCR catalyst 15 by bypassing the reducing agent metering device 16 and the hydrolysis catalyst 17, while the exhaust gas flow through another exhaust gas bypass line is further regulated. Internal combustion engine which can be adjusted by). delete An internal combustion engine according to claim 1 or 2, characterized in that it has a multistage exhaust gas turbocharge system, wherein the particle filter (14) and the SCR catalyst (15) are interposed between the two turbines (12, 25). . An exhaust gas bypass line (18) in which the reducing agent metering device (16) and the hydrolysis catalyst (17) are located surrounds the particle filter (14) and the high pressure turbine (17) located upstream of the particle filter. An internal combustion engine characterized by being guided.

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