KR20170113337A - Exhaust gas after-treatment system and internal combustion engine - Google Patents

Abstract

An exhaust gas after-treatment system 3 of the internal combustion engine, that is, an SCR exhaust gas after-treatment system, is connected to the SCR catalytic converter 9 accommodated in the reactor chamber 10, to the reactor chamber 10 and thus to the SCR catalytic converter 9 And an exhaust gas discharge line 11 leading from the reactor chamber 10 and hence away from the SCR catalytic converter 9, a reducing agent, in particular an ammonia or ammonia precursor material, into the exhaust gas Downstream of the introduction device 16 to mix the exhaust gas with the reducing agent upstream of the introduction device 16, the reactor chamber 10 or the SCR catalytic converter 9, which is assigned to the exhaust gas supply line 8, The mixing section 18 provided by the exhaust gas supply line 8 in the SCR catalytic converter 9 and the thermal energy of the exhaust gas from the exhaust gas downstream of the SCR catalytic converter 9, Includes the heat exchanger 25 will be delivered throw.

Description

[0001] EXHAUST GAS AFTER-TREATMENT SYSTEM AND INTERNAL COMBUSTION ENGINE [0002]

The present invention relates to an exhaust gas aftertreatment system for an internal combustion engine. The present invention also relates to an internal combustion engine having an exhaust gas aftertreatment system.

In combustion processes in fixed internal combustion engines employed in power plants, for example, and in combustion processes in non-fixed internal combustion engines employed, for example, on ships, nitrogen oxides are produced, Nitrogen oxides are typically produced during the combustion of sulfur-containing, fossil fuels such as charcoal, coal, crude oil, heavy oil, diesel fuel. For these reasons, exhaust gas aftertreatment systems are assigned to such internal combustion engines, which function, for cleaning, especially for the denitration of exhaust gases leaving the internal combustion engine.

In order to reduce the nitrogen oxides in the exhaust gas, so-called SCR catalytic converters are mainly employed in exhaust gas aftertreatment systems, known from practice. In the SCR catalytic converter, selective catalytic reduction of nitrogen oxides takes place, and ammonia (NH ₃ ) is required as a reducing agent for the reduction of nitrogen oxides. Ammonia or an ammonia precursor material such as, for example, urea is introduced for this purpose from the upstream of the SCR catalytic converter into the exhaust gas in the liquid state, and the ammonia or ammonia precursor material is mixed with the exhaust gas upstream of the SCR catalytic converter do. To this end, mixing sections are provided between the inlet of the ammonia or ammonia precursor material and the SCR catalytic converter, according to practice.

Although exhaust aftertreatment, particularly nitrogen oxide reduction, has already been successfully accomplished, with the exhaust aftertreatment systems known from the practice including SCR catalytic converters, there is a need to further improve the exhaust aftertreatment systems have. There is a need to enable effective exhaust aftertreatment, especially by the compact design of such exhaust aftertreatment systems.

Starting from this, it is an object of the present invention to build a new type of exhaust gas aftertreatment system of an internal combustion engine and an internal combustion engine having such an exhaust gas aftertreatment system.

This object is solved by an exhaust gas after-treatment system of an internal combustion engine according to claim 1. The exhaust aftertreatment system according to the present invention includes a heat exchanger in which the thermal energy of the exhaust gas can be transferred from the exhaust gas downstream of the SCR catalytic converter to the exhaust gas upstream of the SCR catalytic converter with its help. By means of the heat exchanger, the exhaust gas temperature can be set to an optimal level for the SCR process. The thermal energy released during the exothermic reaction of the SCR process and present in the exhaust gas downstream of the SCR catalytic converter is transferred to the exhaust gas upstream of the SCR catalytic converter. For this reason, effective exhaust gas after-treatment is possible by increasing the temperature upstream of the SCR catalytic converter.

According to another advantageous refinement of the invention, an exhaust gas supply line and an exhaust gas discharge line are connected on the common side of the reactor chamber, and in the sections forming the heat exchanger one of these exhaust gas lines is connected to this exhaust gas line Surrounding one of the other. These other improvements allow efficient exhaust after-treatment by a compact and simple design of the exhaust aftertreatment system.

Preferably, the exhaust emission line surrounds an exhaust gas supply line adjacent to the side of the reactor chamber, both of which are connected to sections on the outer side thereof, A section of the exhaust gas supply line, on the one hand, is surrounded by the exhaust gas emission line and extends into the reactor chamber, on the other hand, where exhaust gas is circulated around the upstream of the SCR catalytic converter. These other improvements allow efficient exhaust after-treatment by a particularly compact and simple design of the exhaust aftertreatment system. In particular, deposition on the walls of the exhaust gas supply line can be avoided.

According to another advantageous refinement of the invention, the ratio between the length of the SCR catalytic converter and the length of the section of the exhaust gas feed line, in which the exhaust gas circulates around and upstream of the SCR catalytic converter, is at least 1: 5 At least 1: 8, particularly preferably at least 1: 10. These other improvements allow efficient exhaust after-treatment by an especially simple and compact design of the exhaust aftertreatment system.

Another improvement consists in increasing the heat transfer by increasing the pressure level of the exhaust gas. Advantageously, the absolute pressure is increased to at least 0.2 MPa, advantageously to at least 0.3 MPa, most advantageously to at least 0.4 MPa. In order to be able to omit the separate compressors for increasing the exhaust gas pressure, it is appropriate to arrange the heat exchanger upstream of the at least one exhaust gas turbine and thus also the SCR catalytic converter.

The internal combustion engine according to the present invention is defined in claim 10.

Other preferred refinements of the invention are achieved from the dependent claims and the ensuing description. BRIEF DESCRIPTION OF THE DRAWINGS Exemplary embodiments of the present invention are described in further detail, not by way of limitation, but by way of the following figures.

1 is a schematic perspective view of an internal combustion engine having an exhaust gas aftertreatment system according to the present invention;
2 is a detailed view of the exhaust aftertreatment system of FIG.

The present invention relates to an exhaust aftertreatment system of an internal combustion engine, for example a stationary internal combustion engine in a power plant or a non-fixed internal combustion engine employed on a ship. Particularly, the exhaust gas aftertreatment system is employed on a diesel engine of a ship to be operated by heavy oil.

1 shows an arrangement of an exhaust gas supercharging internal combustion engine 1 having an exhaust gas turbocharger system 2 and an exhaust gas aftertreatment system 3. The internal combustion engine 1 may be a non-fixed or stationary internal combustion engine, particularly an internal combustion engine operated in non-fixed form of the ship. The exhaust gas leaving the cylinders of the internal combustion engine 1 is introduced into the exhaust gas supercharging system 2 in order to extract the mechanical energy from the thermal energy of the exhaust gas to compress the charge air supplied to the internal combustion engine 1 .

Thus, Figure 1 shows an exhaust gas turbocharger system 2 (not shown), including a plurality of exhaust gas turbochargers, a first exhaust gas turbocharger 4 on the high pressure side and a second exhaust gas turbocharger 5 on the low pressure side ). ≪ / RTI > The exhaust gas leaving the cylinders of the internal combustion engine 1 initially flows through the high pressure turbine 6 of the first exhaust gas turbocharger 4 and is expanded inside the high pressure turbine 6, , And is utilized in the high pressure compressor of the first exhaust gas turbocharger (4) to compress the charge air. In the direction of flow of the exhaust gas downstream of the first turbocharger 4, a second exhaust gas turbocharger 5 is arranged, through a second exhaust gas turbocharger, that is to say a second exhaust gas turbocharger 5, The exhaust gas that has already flowed through the high pressure turbine 6 of the first exhaust gas turbocharger 4 is moved through the low pressure turbine 7 of the first exhaust gas turbocharger 4. In the low pressure turbine 7 of the second exhaust gas turbocharger 5, the exhaust gas is further expanded and the energy extracted from the process is used to compress the charge air to be fed to the cylinders of the internal combustion engine 1 Pressure compressor of the second exhaust gas turbocharger 5, for example.

In addition to the exhaust gas supercharging system 2 comprising exhaust gas turbochargers 4 and 5 the internal combustion engine 1 comprises an exhaust gas aftertreatment system 3 which is an SCR exhaust gas aftertreatment system . The SCR exhaust gas aftertreatment system 3 is connected between the high pressure turbine 6 and the low pressure turbine 7 of the first exhaust gas turbocharger 4 and is thus connected to the high pressure turbine 4 of the first exhaust gas turbocharger 4, The exhaust gas leaving the turbine 6 can be initially moved through the SCR exhaust aftertreatment system 3 before reaching the region of the low pressure turbine 7 of the second exhaust turbocharger 5 . For this reason, the heat exchanger is operated at an elevated pressure level, resulting in improved heat transfer.

Figure 1 shows the exhaust gas from the high pressure turbine 6 of the first exhaust gas turbocharger 4 being moved in the direction of the SCR catalytic converter 9 (Figure 2) in which it is arranged in the reactor chamber 10 The exhaust gas supply line 8 shown in Fig.

1 also shows an exhaust gas emission line 11 which serves to discharge the exhaust gas from the SCR catalytic converter 9 in the direction of the low pressure turbine 7 of the second exhaust gas turbocharger 5. [

The exhaust gas from the low pressure turbine 7 flows through the line 21, in particular outwardly.

The exhaust gas feed line 8 and the reactor chamber 10 leading to the reactor chamber 10 and thus to the SCR catalytic converter 9 disposed in the reactor chamber 10 and hence away from the SCR catalytic converter 9 The ensuing exhaust emission line 11 is coupled via a bypass 12, into which the blocking element 13 is integrated. By the blocking element 13 being closed, the bypass 12 is blocked and therefore the exhaust gas can not flow through the bypass. In contrast, in particular, when the blocking element 13 is open, exhaust gas is passed through the bypass 12, that is to say, bypassing the reactor chamber 10 and thus in the reactor chamber 10, the SCR catalytic converter 9 ), And can flow.

Figure 2 shows the flow of exhaust gas through the exhaust aftertreatment system 3 with the bypass line 12 being closed through the blocking element 13 in the form of arrows 14 wherein the exhaust gas supply line 8 Is opened into the reactor chamber 10 at the downstream side end 15 and the exhaust gas in the region of this end 15 of the exhaust gas supply line 8 is subject to a flow deflection of approximately 180 °, The exhaust gas of the SCR catalytic converter 9 is moved through the SCR catalytic converter 9. As shown in Fig.

The exhaust gas supply line 8 of the exhaust gas aftertreatment system 3 is provided with a catalytic converter 9 which is required to convert the nitrogen oxides of the exhaust gas in a limited manner in the region of the SCR catalytic converter 9, , In particular an ammonia or ammonia precursor material, can be introduced. This introduction device 16 of the exhaust gas aftertreatment system 3 is preferably an injection nozzle through which the ammonia or ammonia precursor material can be injected into the exhaust gas flow inside the exhaust gas feed line 8. [ 2 illustrates the injection of the reducing agent into the exhaust gas in the region of the exhaust gas supply line 8 by means of the conical marker 17. Fig. The section of the exhaust gas aftertreatment system 3, which is located upstream of the SCR catalytic converter 9 downstream of the introduction device 16 as viewed in the flow direction of the exhaust gas, is described as a mixing section. In particular, the exhaust gas supply line 8 provides the mixing section 18 downstream of the introduction device 16 so that the exhaust gas can be mixed with the reducing agent upstream of the catalytic converter 9.

The exhaust gas supply line 8 opens into the reactor chamber 10 at the downstream end 15. This downstream side end 15 of the exhaust gas supply line 8 is provided with a baffle element 20 which can be displaced with respect to the downstream side end 15 of the exhaust gas supply line 8. In the illustrated exemplary embodiment, the baffle element 20 can be linearly displaced with respect to the end 15 of the exhaust gas supply line 8, which opens into the reactor chamber 10.

The baffle element 20 is connected to the exhaust gas supply line 8 to shut off the exhaust gas supply line 8 at the downstream end 15 or to open the exhaust gas supply line 8 at the downstream end 15 8 with respect to the downstream-side end 15 thereof. In particular when the baffle element 20 cuts off the exhaust gas feed line 8 at the downstream end 15 the blocking element 13 of the bypass 12 is now closed by the SCR catalytic converter 9 or the SCR catalytic converter 9 To move the exhaust gas completely bypassing the reactor chamber 10 containing the exhaust gas.

Particularly when the baffle element 20 opens the downstream end 15 of the exhaust gas supply line 8, the blocking element 13 of the bypass 12 can be completely closed or at least partially open. The relative position of the baffle element 20 with respect to the downstream end 15 of the exhaust gas supply line 8, particularly when the baffle element 20 opens the downstream end 15 of the exhaust gas supply line 8, Particularly the exhaust gas mass flow rate through the exhaust gas supply line 8 and / or the exhaust gas temperature of the exhaust gas in the exhaust gas supply line 8 and / or the reducing agent introduced into the exhaust gas flow through the introduction device 16 Depending on the quantity.

Another function of the baffle element 20 with the open downstream end 15 of the exhaust gas supply line 8 is to allow any droplets of liquid reducing agent present in the exhaust gas flow to reach the baffle element, The droplets in the baffle element are trapped and atomized to prevent droplets of the reducing agent from reaching the region of the SCR catalytic converter 9. [ The relative position of the baffle element 20 with respect to the downstream end 15 of the exhaust gas supply line 8 together with the open downstream end 15 allows the exhaust gas supply in the region of the baffle element 20, The exhaust gas deflected in the region of the downstream end 15 of the line 8 is supplied to the SCR catalytic converter 9 which is arranged in the direction of the sections of the SCR catalytic converter located further radially inward or more radially outward In the direction of the sections, whether to be moved or pulled can be determined.

According to a preferred embodiment, the exhaust gas supply line 8 is expanded in a funnel shape at the downstream end 15 to form a diffuser. The flow cross sectional area of the exhaust gas supply line 8 increases in the region of the downstream side end portion 15 so that the upstream side of the downstream side end portion 15 of the exhaust gas supply line 8 Sectional area of the exhaust gas supply line can be initially reduced when viewed in the flow direction of the exhaust gas in the exhaust gas supply line. 2 shows that the flow cross sectional area of the exhaust gas supply line 8 is initially substantially constant as viewed in the flow direction of the exhaust gas downstream of the introduction device 16 for the reducing agent, And finally extends in the region of the downstream end 15. This enlargement of the flow cross sectional area at the downstream end 15 of the exhaust gas supply line 8 is such that the exhaust gas supply line 8 initially narrows in front of the downstream end 15 therethrough, Which is preferably influenced by a shorter section of the exhaust gas supply line 8 than such a section. The SCR catalytic converter 9 is arranged radially outward of the exhaust gas supply line 8 at such an axial position of the exhaust gas supply line 8 in which the flow direction of the exhaust gas initially becomes gradually narrower.

Preferably, the baffle element 20 is curved and bell-like curved on the side 22 facing the exhaust gas supply line 8, preferably to form a flow guide for the exhaust gas. The side surface of the baffle element 20 facing the downstream side end portion 15 of the exhaust gas supply line 8 is located in the radial direction of the baffle element 20 with respect to the downstream side end portion 15 of the exhaust gas supply line 8 On the inner section, on the radially outer section of the baffle element. Thus, the baffle element 20 is pulled or curved at the center in the direction of the downstream end 15 of the exhaust gas supply line 8 against the flow direction of the exhaust gas.

2, the exhaust gas supply line 8 and the exhaust gas emission line 11 are connected together on the first side 24 of the reactor chamber 10, And is opened or extended into the reactor chamber 10.

Herein, the exhaust gas supply line 8 is an exhaust gas supply line in which the downstream end 15 of the exhaust gas supply line 8 is located opposite the first side 24 of the reactor chamber 10, The exhaust gas discharge line 11 is opened into the reactor chamber 10 on the first side 24 in such a way that it is positioned adjacent to the two side faces 23 of the reactor chamber 10, The exhaust gas supplied through the exhaust gas supply line 8 is supplied to the second side surface 23 of the reactor chamber 10 which is positioned opposite the downstream side end portion 15 of the exhaust gas supply line 8. [ And then flows through the SCR catalytic converter 9 and subsequently through the first side 24 into the region of the exhaust emission line 11. Between the second side 23 of the reactor chamber 10 which is located opposite the first side 24 of the reactor chamber 10 a wall 10 of the reactor chamber 10, .

According to the present invention, the exhaust gas aftertreatment system 3 is one in which the thermal energy of the exhaust gas can be transferred from the exhaust gas downstream of the SCR catalytic converter 9 to the exhaust gas upstream of the SCR catalytic converter 9 , And a heat exchanger (25). The thermal energy released during the exothermic reaction of the SCR process and present in the exhaust gas downstream of the SCR catalytic converter is transferred to the exhaust gas upstream of the SCR catalytic converter. For this reason, the exhaust gas temperature can be set to a level that is optimal for the SCR process and enables efficient exhaust gas after-treatment.

An exhaust gas supply line 8 and an exhaust gas emission line 11 are connected together on a first side 24 of the reactor chamber 10 and one of these exhaust gas lines 8, In part, encloses the other of these exhaust gas lines 8, 11 to form the exhaust gas line 25. In the illustrated preferred exemplary embodiment, the exhaust gas emission line 11 is arranged so that both the exhaust gas lines 8, 11 are partly externally and preferably concentrically connected thereto, Surrounding the exhaust gas supply line 8, near the one side 24.

Because of this, the thermal energy present in the exhaust gas downstream of the SCR catalytic converter can be reliably transferred to the exhaust gas upstream of the SCR catalytic converter 9, by means of a compact and simple design of the exhaust gas aftertreatment system 3 . There is no risk that deposits will form in the region of the exhaust gas supply line 8.

The exhaust gas discharge line 11 surrounds the exhaust gas supply line 8 in the region of the mixing section 18. The section of the exhaust gas supply line 8 surrounded by the section of the exhaust gas emission line 11 is an introduction device for introducing the reducing agent into the exhaust gas when viewed in the flow direction of the exhaust gas supply line 8 16 and in the mixing section 18 accordingly.

The length l1 of the SCR catalytic converter 9 and the length of the section of the exhaust gas supply line 8 circulating around the exhaust gas upstream of the SCR catalytic converter 9 12) is at least 1: 5, preferably at least 1: 8, particularly preferably at least 1:10. For this reason, the thermal energy present in the exhaust gas downstream of the SCR catalytic converter 9 can be reliably transferred to the exhaust gas upstream of the SCR catalytic converter 9.

The section of the exhaust gas supply line 8 in which the exhaust gas circulates around the upstream of the SCR catalytic converter 9 is surrounded on the one hand by the exhaust gas emission line 11 and on the other hand is surrounded by the reactor chamber 10 Lt; / RTI > The length 12 of such a section of the exhaust gas supply line 8, in which the exhaust gas circulates around the upstream of the SCR catalytic converter, thus corresponds to the length of the partial section 12, which is surrounded by the exhaust gas emission line 11. [ And a partial section length l22 that extends inside the reactor chamber 10. [

The reactor chamber 10 and / or the exhaust gas discharge line 11 and / or the exhaust gas supply line 8 are arranged such that the flow cross sectional area for the exhaust gas, when viewed in the flow direction of the exhaust gas, Lt; / RTI > This is ensured by the conical contouring of the first side 24 of the reactor chamber 10 in the exemplary embodiment. Through this narrowing of the flow cross-sectional area, the prescribed flow rate can be used to transfer the heat energy present in the exhaust gas downstream of the SCR catalytic converter to the exhaust gas upstream of the SCR catalytic converter 9, Is arranged within the section of the exhaust gas emission line (11), which surrounds the exhaust gas supply line (8) from the outside to form the exhaust gas outlet line (25).

In the case of the internal combustion engine 1 of Fig. 1, the exhaust gas aftertreatment system 3 is arranged in an upright position upstream of the exhaust gas supercharging system 2. Access to the cylinders of the internal combustion engine 1 is free, but the accessibility to the exhaust gas turbochargers 4, 5 is limited. When a maintenance work is required on the turbochargers 4, 5, the reactor chamber 10 can however simply be disassembled. In contrast to the upright arrangement of the exhaust gas aftertreatment system 3 upstream of the exhaust gas supercharging system 2 shown in Fig. 1, the exhaust gas aftertreatment system 3 has 90 A horizontal arrangement that is inclined by [deg.] Is also possible, but such a horizontal arrangement increases the length of the device. However, the internal combustion engine 1 and the exhaust gas supercharging system 2 are now available without any limitation on maintenance work, without the need to disassemble the reactor chamber 10.

Particularly preferably, the present invention is used with two-stage supercharged four-stroke engines or two-stroke, when the exhaust gas temperature upstream of the SCR catalytic converter is less than 300 ° C. In such engines, the exhaust gas temperature can be adjusted by the present invention to a level optimal for SCR processing.

1: Internal combustion engine 2: Exhaust gas supercharging system
3: Exhaust gas aftertreatment system 4: Exhaust gas turbocharger
5: Exhaust gas turbocharger 6: High pressure turbine
7: Low pressure turbine 8: Exhaust gas supply line
9: SCR catalytic converter 10: reactor chamber
11: Exhaust gas emission line 12: Bypass
13: Blocking element 14: Exhaust gas guide
15: end portion 16: introduction device
17: injection cone cover 18: mixing section
19: wall 20: baffle element
21: line 22: side
23: side 24: side
25: Heat exchanger

Claims (14)

An exhaust gas aftertreatment system (3) of an internal combustion engine, that is, an SCR exhaust aftertreatment system of an internal combustion engine, comprises an SCR catalytic converter (9) accommodated in a reactor chamber (10) An exhaust gas feed line 8 leading to the converter 9 and an exhaust gas emission line 11 leading from the reactor chamber 10 and hence away from the SCR catalytic converter 9 and a reducing agent and in particular an ammonia or ammonia precursor material An introduction device 16 which is assigned to the exhaust gas supply line 8 and an introduction device 16 for mixing the exhaust gas with the reducing agent upstream of the reactor chamber 10 or the SCR catalytic converter 9, 16. The exhaust aftertreatment system according to claim 1, wherein the mixing section (18) is provided by an exhaust gas supply line (8)
Characterized in that in the reactor chamber (10) at least one blow-down device (24) is arranged, which serves to purify the SCR catalytic converter (9). The method according to claim 1,
Characterized in that the pressure in the heat exchanger reaches an absolute pressure of at least 0.2 MPa, advantageously at least 0.3 MPa, most advantageously at least 0.4 MPa. 3. The method according to claim 1 or 2,
Wherein the heat exchanger is arranged upstream of at least one turbine of the exhaust gas supercharging internal combustion engine. The method according to claim 1,
The exhaust gas supply line 8 and the exhaust gas emission line 11 are connected together on the side surface 24 of the reactor chamber 10 and one of these exhaust gas lines forms a heat exchanger 25 And, in part, surrounds the other of these exhaust lines. 3. The method of claim 2,
The exhaust gas emission line 11 is connected to the exhaust gas supply line 8 in the vicinity of the side surface 24 of the reactor chamber 10 where both the exhaust gas lines 8 and 11 are partly outsidely connected thereto And the exhaust gas after-treatment system. 6. The method of claim 5,
Wherein the exhaust gas discharge line (11) concentrically surrounds the exhaust gas supply line (8). The method according to claim 5 or 6,
Characterized in that the exhaust emission line (11) surrounds the exhaust gas supply line (8), on the outside, in the region of the mixing section (18). 8. The method according to any one of claims 5 to 7,
The section of the exhaust gas supply line 8 surrounded by the section of the exhaust gas emission line 11 is an introduction device for introducing the reducing agent into the exhaust gas when viewed in the flow direction of the exhaust gas supply line 8 16. The exhaust aftertreatment system according to claim 1, 9. The method according to any one of claims 5 to 8,
The ratio between the length of the SCR catalytic converter 9 and the length of the section of the exhaust gas supply line 8 circulating around the exhaust gas upstream of the SCR catalytic converter 9 is at least 1: At least 1: 8, particularly preferably at least 1: 10. 10. The method according to any one of claims 5 to 9,
The section of the exhaust gas supply line 8 in which the exhaust gas circulates around upstream of the SCR catalytic converter 9 is surrounded on the one hand by the exhaust gas emission line 11 and on the other hand the reactor chamber 10 ) Of the exhaust gas. ≪ / RTI > 11. The method according to any one of claims 5 to 10,
The reactor chamber 10 and / or the exhaust gas discharge line 11 and / or the exhaust gas supply line 8 are arranged so as to have a flow cross sectional area for the exhaust gas downstream of the SCR catalytic converter 9, as viewed in the flow direction of the exhaust gas Wherein the exhaust gas treatment system is contoured in a narrowing manner. The internal combustion engine (1), in particular an internal combustion engine operated by diesel fuel or heavy fuel oil, comprising an exhaust gas after-treatment system (3) according to any one of claims 1 to 11, . 13. The method of claim 12,
An exhaust gas aftertreatment system (2) comprising at least one exhaust turbocharger (4), wherein the exhaust gas aftertreatment system (3) is connected between the cylinders of the internal combustion engine and the exhaust gas supercharging system And the internal combustion engine. 13. The method of claim 12,
A multistage exhaust supercharging system (2) comprising a first exhaust gas turbocharger (4) comprising a high pressure turbine (6) and a second exhaust gas turbocharger (5) comprising a low pressure turbine (7) And the exhaust gas aftertreatment system (3) is connected between the high pressure turbine (6) and the low pressure turbine (7).

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