JP6530222B2 - Exhaust gas aftertreatment system and method for exhaust gas aftertreatment - Google Patents

Description

  The present invention relates to an exhaust gas aftertreatment system. The invention further relates to a method for exhaust gas aftertreatment.

  In order to minimize carbon-containing particulate matter from combustion, so-called particle filters are usually used. A typical particle filter configuration is known from US Pat. In such particulate filters, a filter media comprised of a ceramic, metal or fibrous substrate receives a throughflow of exhaust gas. Particles contained in the exhaust gas are accumulated in the filter material and are thus prevented from reaching the clean gas side of the filter. The filter must be cleaned or replaced at regular intervals as it will plug with ash from the burned engine oil or fuel as the age of use increases. For replacement, the facility has to be shut down, which leads to undesirable down time, especially when it comes to power plant or ship equipment with high age and availability requirements.

From experience, the particle filter, at least one exhaust gas post-treatment assembly disposed upstream of the particle filter in the flow direction of the exhaust gas, and at least downstream of the particle filter in the flow direction of the exhaust gas An exhaust gas aftertreatment system for an internal combustion engine is known, comprising one exhaust gas aftertreatment assembly. The exhaust gas post-treatment assembly arranged upstream in the flow direction of the particle filter is, in particular, an oxidation catalytic converter for the oxidation of nitric oxide (NO) to nitrogen dioxide (NO ₂ ). The exhaust gas aftertreatment assembly arranged downstream in the flow direction of the particle filter may be a silencer. Specifically, when viewed in the flow direction of the exhaust gas stream, an oxidation catalytic converter for the oxidation of NO to NO ₂ is placed upstream of the particle filter, and NO is converted to NO ₂ according to the formula It is oxidized in the oxidation catalytic converter with the aid of residual oxygen O ₂ contained in the exhaust gas flowing into it.
2NO + O ₂ ⇔ 2NO ₂

  During this oxidation of nitric oxide to nitrogen dioxide, the equilibrium of the oxidation reaction at high temperature is on the side of nitric oxide. The achievable constituents of nitrogen dioxide are thereby largely limited at high temperatures.

In a particulate filter, the nitrogen dioxide extracted by the oxidation catalytic converter is carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen (N ₂ ), and one of carbon-containing particles, so-called soot, collected in the particulate filter. It is converted to nitric oxide (NO). In the process, continuous removal of carbon-containing particulate matter or soot accumulated in the particle filter is performed in the sense of passive regeneration of the particle filter, this conversion is performed according to the following equation .
2NO ₂ + C → 2NO + CO ₂
NO ₂ + C → NO + CO
2C + 2NO ₂ → N ₂ + 2CO ₂

  In particular, if such a passive regeneration of the particle filter does not allow a complete conversion of the carbon-containing particulate matter accumulated in the particle filter or soot, the carbon component in the particle filter or The soot content increases, and the particulate filter then has a tendency towards clogging, as a result of which the so-called exhaust gas profile in the internal combustion engine located upstream of the exhaust gas aftertreatment system is eventually The pressure increases. The increasing exhaust gas back pressure in an internal combustion engine reduces the power of the internal combustion engine and causes an increase in fuel consumption.

  It is also already known from experience to apply a catalytic coating to the particle filter to avoid an increase in or of the carbon-containing particulate matter in the particle filter and thus to avoid clogging of the particle filter There is. Here, platinum-containing coatings are preferentially used. The use of such a particulate filter with a catalytic coating, however, can only prevent clogging of the particulate filter by the carbon-containing particulate matter, ie soot, to an insufficient extent.

  Specifically, this is typically a marine diesel engine, where the internal combustion engine on which the exhaust gas aftertreatment system is operated is operated with a high sulfur content fuel, such as, for example, heavy oil fuel. Sometimes there is a further problem that, due to the intensive accumulation of ash, clogging of the particulate filter of the exhaust gas aftertreatment system can likewise occur. Specifically, in the case of heavy oil fuel operated internal combustion engines, the maintenance intervals of the particle filter can be dramatically shortened by the ash, so that the meaningful operation of the exhaust gas aftertreatment system It will no longer be possible.

U.S. Pat. No. 4,415,344

  Starting from this, the invention is based on the object of creating a new type of exhaust gas aftertreatment system and a new type of method for exhaust gas aftertreatment. This object is solved by an exhaust gas aftertreatment system according to claim 1.

  The exhaust gas aftertreatment system according to the invention comprises a particle separator in the form of a particulate-containing moving bed reactor or fluidized bed reactor downstream of the internal combustion engine for removing soot or ash particles from the exhaust gas, In the separator, the exhaust gas to be purified can be supplied to the particle separator via at least one exhaust gas supply line, and in the particle separator the purified exhaust gas can be at least one exhaust gas discharge line The particulates can be discharged via the particulate separator via the at least one particulate supply and the particulates can be fed to the particulate separator via the at least one particulate discharge from the particulate separator via the at least one particulate discharge. Exhaust gas in the particle separator may flow around the particles, and in the process, soot and ash particles adhere to the particles and / or are bound to the particles and / or particulate Body and reaction , Granulate together with soot and ash particles and / or reaction products thereof, may be discharged from the particle separator through the or each granulate discharge unit.

  Furthermore, the exhaust gas post-treatment system according to the invention is for separating soot and ash particles emitted from the particle separator and / or their reaction products from the particulates together with the particulates, and for the soot and ash particles Separation device assigned to a particle separator for at least partial return of particles separated therefrom and / or from their reaction products into a particle separator via at least one particle feed Equipped with

  The invention proposes an exhaust gas aftertreatment system comprising at least one particle separator in the form of a particulate-containing moving bed reactor or a fluidized bed reactor and a separation device assigned to the particle separator. In the particle separator, soot and ash particles can be effectively separated from the exhaust gas and can be discharged via particulates. In the separation device, the particulates are separated from the soot and ash particles and / or from the reaction products of the particulates and soot and ash particles, in order to at least partially return the cleaned particulates back to the particle separator. It can be done. Thus, effective exhaust gas purification, ie removal of soot and ash particles from the exhaust gas of an internal combustion engine, is possible. Specifically, for example, in the case of heavy oil fuel operated internal combustion engines used on ships, effective removal of soot and ash particles from the exhaust gases of the internal combustion engine may be realized.

  According to an advantageous further development, the particle separator can be such that the exhaust gas passes horizontally through the particle separator, the particles can be fed to the particle separator via the or each particle feed and the bottom The particulate matter may be discharged from the or each granular material discharge part, and the movement or flow direction of the granular material between the or each granular material supply part and the or each granular material discharge part in the vertical direction may be the flow of exhaust gas. It is designed as a cross-flow moving bed reactor or fluidized bed reactor for exhaust gas and particulates so as to cross the direction. Such cross flow particle separators allow particularly effective removal of soot and ash particles from the exhaust gases of internal combustion engines.

  Preferentially, the particle separator is embodied in multiple stages and the exhaust gas flows continuously through the individual stages of the particle separator, in each stage the chemical composition of the granules and / or the particles The size of the body and / or the speed of movement or flow of the particles and / or the flow rate of the exhaust gas deviate from one another. The effectiveness of the removal of soot and ash particles from the exhaust gas of an internal combustion engine can thereby be further improved.

According to an advantageous further development, the exhaust gas aftertreatment system comprising for the oxidation of SO ₂ to SO _3, an oxidation catalytic converter arranged downstream of the internal combustion engine upstream of the particle separator, SO ₃ and And / or condensed H ₂ SO ₄ serves for the direct oxidation of soot in the particle separator. Through the oxidation catalytic converter for the oxidation of SO ₂ to SO ₃ , the oxidation of soot in the particle separator can be improved.

According to a further advantageous further development, the oxidation catalytic converter for oxidation of NO to NO ₂ is upstream of the particle separator, arranged downstream of the internal combustion engine, NO ₂ is soot in the particle separator Useful for oxidation, an oxidation catalytic converter for the oxidation of NO to NO ₂ is connected in parallel to the oxidation catalytic converter for the oxidation of SO ₂ to SO ₃ and from the exhaust gas stream via a shutoff valve It can be blocked. During operation of an internal combustion engine with a fuel that is relatively rich in sulfur, the exhaust gas stream can be conducted through an oxidation catalytic converter for the oxidation of SO ₂ to SO _3, and the internal combustion engine with a fuel that is relatively low in sulfur during operation, the exhaust gas stream can be conducted through the oxidation catalytic converter for oxidation of NO to NO _2. This configuration is advantageous when an internal combustion engine with different types of fuel is operated. This is the case of a marine engine.

In the case of an internal combustion engine with exhaust gas turbocharger, an oxidation catalytic converter for the oxidation of SO ₂ to SO ₃ is arranged upstream of the turbine of the exhaust gas turbocharger, and the particle separator is upstream of the turbine Will be placed. The oxidation of SO ₂ to SO ₃ at the oxidation catalytic converter is promoted because of the relatively high temperature and pressure present upstream of the turbine.

  According to a further advantageous further development, the exhaust gas aftertreatment system according to the invention can, on the one hand, be supplied with an oxidizing agent for the oxidation of soot and, on the other hand, soot and particulates separated from particulate matter in the separation device. A reactor is provided downstream of the separation device, to which ash particles can be supplied. Downstream of the separation device, the ash separated from the particulates can thus be effectively released from the weir. The reactor may also be arranged between the particle separator and the separation device, in a further embodiment, so that the carbon-containing soot can be oxidized even before it enters the separation device. A method for exhaust gas aftertreatment according to the invention is defined in claim 15.

  Preferred further developments of the invention result from the dependent claims and the following description. Exemplary embodiments of the invention are described in more detail with the aid of the drawings, without being limited thereto.

FIG. 1 is a block diagram of a first exhaust gas aftertreatment system according to the invention; FIG. 2 is a detail of FIG. 1; Figure 2 is a block diagram of a second exhaust gas aftertreatment system according to the invention; FIG. 5 is a block diagram of a third exhaust gas aftertreatment system according to the invention; FIG. 5 is a block diagram of a fourth exhaust gas aftertreatment system according to the invention; Figure 5 is a block diagram of a fifth exhaust gas aftertreatment system according to the invention;

  The present invention relates to an exhaust gas aftertreatment system for internal combustion engines used on ships, preferably operated on fuel rich in sulfur, for example heavy fuel oil, for example.

  FIG. 1 shows a first exemplary embodiment of an exhaust gas aftertreatment system 2 arranged downstream of an internal combustion engine 1. The exhaust gas post-treatment system 2 of FIG. 1 comprises a particle separator 3 located downstream of the internal combustion engine 1. The particle separator 3 is a particulate-containing moving bed reactor or fluidized bed reactor which serves to remove soot and ash particles from the exhaust gas of the internal combustion engine 1.

  At least one further exhaust gas aftertreatment component of the exhaust gas aftertreatment system, viewed in the flow direction of the exhaust gas upstream of the particle separator 3 and also in the flow direction of the exhaust gas downstream of the particle separator 3 It is pointed out here that each can be arranged.

  The particle separator 3 can be supplied with exhaust gas to be purified in the particle separator 3 via at least one exhaust gas supply line 4. The exhaust gas purified by the particle separator 3 can be discharged from the particle separator 3 via at least one exhaust gas discharge line 5. The granules required in the particle separator 3 can be supplied to the particle separator 3 via at least one particle supply 6, the particles being separated off via at least one particle outlet 7 It can be discharged from the vessel 3.

  In the particle separator 3, the exhaust gas circulates around the granules, and in the process soot and ash particles from the exhaust gas adhere to the granules and / or are bound to the granules and / or The particulates, which react with the particulates, the particulates with the soot and the ash particles, and / or the reaction products thereof, can be discharged from the particle separator 3 via the or each particulate discharge 7.

  The particle separator 3 is assigned a separation device 8. The separation device 8 can supply the particles discharged from the particle separator 3 through the or each particle discharge portion 7 together with the soot and ash particles and / or the reaction product thereof, the separation device 8 Separates soot and ash particles and / or their reaction products from the granules. Soot and ash particles, and / or their reaction products can be discharged from the separation device 8 following separation from the granules, according to arrow 9, the cleaned granules, according to arrow 10, at least one granule It can be at least partially returned into the particle separator 3 via the feed 6.

  FIG. 2 shows the details of the particle separator 3 and the particle separator 3 schematically illustrated in FIG. 2 is embodied in multiple stages. The exhaust gas to be purified in the particle separator 3, which may be supplied to the particle separator 3 of FIG. 2 via the exhaust gas supply line 4, flows first through the first stage 11, and then subsequently Flow through the second stage 12 of the particle separator 3 to be discharged from the particle separator 3 via the exhaust gas discharge line 5. Both stages 11 and 12 of the particle separator 3 are each embodied as a moving bed reactor or a fluidized bed reactor, each of these two stages 11 and 12 via the granulate feed 6 The granulates 13 and 14 required in the respective stages 11, 12 can be respectively supplied, and the respective granulates 13, 14 can be discharged from the respective stages 11, 12 via the granulate outlet 7 .

  Specifically, as shown in FIG. 2, when the particle separator 3 is embodied in multiple stages, the chemical composition of the granules 13, 14 and / or the size of the granules 13, 14 and / or The velocity of movement or flow of the granules 13, 14 and / or the flow velocity of the exhaust gas can preferentially be offset from one another in the individual stages 11, 12 of the particle separator 3.

  Thus, for example, in the individual stages 11, 12, it is possible to use granules having the same chemical composition but different particle sizes and different migration or flow rates. Furthermore, it is possible, for example, to use particulates 13, 14 with different chemical compositions in the individual stages 11, 12, ie catalytically active on the one hand and catalytically inactive ones on the other hand is there. In particular, the size of the granules and / or the speed of movement or flow of the granules are individual, even when different granules 13, 14 are used in respect of their chemical composition in the individual stages 11, 12 Can be offset from one another in stages 11 and 12.

  The particle separator 3 embodied as a moving bed reactor or fluidized bed reactor is preferentially a particle separator 3 with a cross flow of exhaust gas and granules.

  Thus, the exhaust gas passes horizontally through the particle separator 3, while the granules 13 and 14 of the individual stages 11 and 12 of the respective stages 11 and 12 respectively can be fed from the top, respectively from the bottom It can be discharged from the stages 11 and 12, and the movement and flow direction of the respective particulates 13 and 14 proceeds vertically from the top to the bottom crossing the flow direction 24 of the exhaust gas, specifically, It is clear from FIG. This enables a particularly effective removal of soot and ash particles in the particle separator 3.

  As already explained above, catalytically inactive particles can be used as particles 13, 14 in the particle separator 3. Here, cordierite, granite, corundum, silicon carbide, aluminum oxide or granules of metallic material may in particular be used. By deflecting the soot and ash particles in the stages 11 and 12 of the particle separator 3, the soot and ash particles are particulated via impaction and / or diffusion and / or interception. Separated above.

FIG. 3 shows a further development of the exhaust gas aftertreatment system 2 of FIG. 1, downstream of the separation device 8 a reactor 15 is arranged. The reactor 15 may, on the one hand, be supplied with soot and ash particles starting from the separation device 8 according to arrow 9 and likewise be supplied with oxidant according to arrow 16. In the reactor 15, soot particles are oxidized to thereby release soot ash. The ash released from the weir can be discharged from the oxidation catalytic converter 15 according to the arrow 17. The CO ₂ created during soot oxidation is discharged from the reactor 15 according to arrow 18.

As an oxidizing agent in reactor 15, H ₂ SO ₄ and / or HNO ₃ and / or NO ₂ and / or SO ₃ and / or SO ₂ may be preferentially utilized. Specifically, when the NO ₂ and / or SO ₃ from the reactor 15 is utilized as an oxidant, these oxidants can be used to catalyze the catalyst 24 through the oxidation of NO and / or SO ₂ contained in the exhaust gas. Can be generated by H ₂ SO ₄ and HNO ₃ can be extracted via subsequent condensation. H ₂ SO ₄ (sulfuric acid) can oxidize the soot effectively, in particular at temperatures below 250 ° C. Condensation can take place in a separate condenser 25 and / or in the reactor 15.

The oxidation of soot in the oxidation catalytic converter 15 with the aid of SO ₃ as oxidant in this case takes place according to the following reaction equation:
2SO ₃ + C → CO ₂ + 2SO ₂
SO ₃ + C → CO + SO ₂

  A heating device is provided upstream of the oxidation catalytic converter 15 to heat the soot and ash particles supplied to the oxidation catalytic converter 15 to a defined process temperature in order to promote the oxidation of soot at the oxidation catalytic converter 15. Can be placed.

A further exemplary embodiment of the exhaust gas aftertreatment system 2 assigned to the internal combustion engine 1 is illustrated by FIG. 4, the exemplary embodiment of FIG. 4 being arranged upstream of the particle separator 3 in the internal combustion engine 1. The downstream embodiment differs from the exemplary embodiment of FIG. 1 in that an oxidation catalytic converter 19 for the oxidation of SO ₂ to SO ₃ is provided. In the oxidation catalytic converter 19, the oxidation of SO ₂ to SO ₃ is performed according to the following reaction formula.
2SO ₂ + O ₂ ⇔ 2SO ₃

In the oxidation catalytic converter 3, SO ₂ contained in the exhaust gas of the internal combustion engine 1 is oxidized to SO _3, SO ₃ extracted in this process is useful for the oxidation of direct soot in the particle separator 3 . The oxidation of soot in the particle separator _{3 with} the aid of SO ₃ formed in the oxidation catalytic converter 19 in this case takes place again according to the following reaction equation:
2SO ₃ + C → CO ₂ + 2SO ₂
SO ₃ + C → CO + SO ₂

If the exhaust gas is cooled below the sulfuric acid dew point, condensation of H ₂ SO ₄ (sulfuric acid) is performed according to the following reaction equation:
SO ₃ + H ₂ O → H ₂ SO ₄
Here, H ₂ SO ₄ can likewise be used for the oxidation of soot in the particle separator 3. Here, sulfuric acid can effectively oxidize soot at exhaust gas temperatures specifically below 250 ° C.

The oxidation catalytic converter 19 comprises vanadium (V), and / or potassium (K), and / or sodium (Na), and / or iron (for example), and / or cerium (Ce) , and / or cesium (Cs) And / or oxides of these elements are used as active components for the oxidation of SO ₂ to SO ₃ , wherein the oxidation catalytic converter 19 is a titanium oxide TiO ₃ stabilized by tungsten oxide WO _{3 2} and / or preferentially utilize silicon oxide SiO ₂ . The component of vanadium in the oxidation catalytic converter 19 which is present as an active component for the oxidation of SO ₂ to SO ₃ is more than 5%, preferably more than 7%, particularly preferably more than 9%. . It is also possible to introduce vanadium into the exhaust gas and / or to use a vanadium-containing fuel to operate an internal combustion engine. The vanadium component is at least 20 mg / kg, preferably 50 mg / kg, most preferably 75 mg / kg. The conversion of SO ₂ to SO ₃ in the oxidation catalytic converter 19 is at least 7: 1, preferably at least 12: 1, particularly preferably at least 16 in the region of the particle separator 3 downstream of the oxidation catalytic converter 19. It is carried out such that a mass ratio between SO ₃ and 煤 of 1: 1 is present.

5 shows a further development of the exhaust gas aftertreatment system 2 of FIG. 4, the internal combustion engine of FIG. 5 being an internal combustion engine with an exhaust gas turbocharger, the exhaust gas for extracting mechanical energy; Exhaust gas turbo exhaust which is expanded in the turbine 20 of the exhaust gas turbocharger and whose mechanical energy is not shown in order to compress the charge air to be supplied to the internal combustion engine 1 in the compressor of the exhaust gas turbocharger. Help to drive the feeder compressor. Specifically, when the exhaust gas post-treatment system 2 accordingly comprises a turbine 20 as shown in FIG. 5, the oxidation catalytic converter 19 is arranged upstream of the turbine 20 and the particle separator 3 of the turbine 20 is It is located downstream. The high pressure and temperature upstream of the exhaust gas turbocharger turbine 20 aids the oxidation of SO ₂ to SO ₃ at the oxidation catalytic converter 19.

A further advantageous further development of the exhaust gas aftertreatment system 2 of FIG. 4 is illustrated by FIG. 6 and the version of FIG. 6 specifically relates to a fuel having a relatively high sulfur content and a relatively low sulfur content. It is utilized in an internal combustion engine 1 which is operated with both fuel having a quantity. Thus, FIG. 6 comprises an oxidation catalytic converter 19 arranged upstream of the internal combustion engine 1 and a particle separator 3 arranged downstream of the oxidation catalytic converter 19 for the oxidation of SO ₂ to SO ₃ . Although an exhaust gas aftertreatment system 2, an exhaust gas aftertreatment system 2 in FIG. 6 includes an additional oxidation catalytic converter 21 for the oxidation of NO to NO _2. The NO ₂ extracted by the oxidation catalytic converter 21 likewise serves for the oxidation of soot in the particle separator 3. In FIG. 6, the oxidation catalytic converter 21 for the oxidation of NO to NO ₂ is connected in parallel with the oxidation catalytic converter 19 for the oxidation of SO ₂ to SO ₃ and the exhaust gases of the internal combustion engine are shut off Depending on the opening position of 22, 23, it is conducted through either the oxidation catalytic converter 19 or the oxidation catalytic converter 21.

In particular, when the internal combustion engine 1 is operated with a fuel which is relatively rich in sulfur, the exhaust gas stream of the internal combustion engine 1 then carries out the oxidation catalytic converter 19 for the oxidation of SO ₂ to SO ₃ . The shut-off valve 22 is opened and the shut-off valve 23 is closed so that the oxidation catalytic converter 21, which is conducted through and is oxidized for NO to NO ₂ , is separated from the exhaust gas stream. In contrast, if the internal combustion engine 1 of FIG. 6 is operated with a fuel containing relatively little sulfur, the exhaust gas is conducted through the oxidation catalytic converter 21 for the oxidation of NO to NO ₂ , SO _The shutoff valve 23 is opened and the shutoff valve 22 is closed so that the oxidation catalytic converter 19 for the oxidation of SO ₂ to ₃ is separated or shut off from the exhaust gas stream. The version of FIG. 6 is particularly suitable for use in marine engines operated on fuels which are relatively rich in sulfur and on the other hand relatively low in sulfur.

Specifically, during operation of the internal combustion engine 1 with a fuel rich in sulfur, the oxidation catalytic converter 21 serving for the oxidation of NO to NO ₂ remains sulfur-free when the shut-off valve 23 is closed. become.

  An alternative to this is to omit the shut-off valve and to operate the oxidation catalytic converter 21 following operation with a fuel rich in sulfur, so that the exhaust gas temperature is increased and thus sulfur is desorbed at the oxidation catalytic converter 21. It is about making it suitable. The version with the shut-off valves 22, 23 is, however, preferred because, following the operation of the internal combustion engine 1 with a fuel containing sulfur, the oxidation catalytic converter 21 is immediately ready for subsequent operation.

  In the above exemplary embodiments, the exhaust gas can flow continuously through the particle separator 3 and the particulates can be supplied to the particle separator 3 continuously or periodically, and the particles separated continuously or periodically. It can be discharged from the vessel 3.

  The separation device 8 of the above exemplary embodiments may be, for example, a drum peeler, a drum screen, a vibrating screen, a mill, or a washing device using water as a washing medium for washing the granules.

  As already mentioned above, catalytically active granules can also be used as granules 13, 14 in the particle separator 3. In this case, the components of the exhaust gas can be reacted with the particles in the particle separator 3 and the drum peeler can then, in turn, react with the shells of the particles that are reacting with the components of the exhaust gas, the components of the exhaust gas. And the separation device 8 in order to separate it from the nuclei of the particles that have not yet reacted.

  According to the method for exhaust gas post-treatment of the exhaust gas leaving the internal combustion engine according to the invention, the exhaust gas is conducted via the particle separator 3 and soot and ash with the particulates discharged from the particle separator 3 The particles and / or their reaction products are separated from the particulates in the separating device 8 and the particulates separated from the soot and ash particles and / or their reaction products are at least partially returned to the particle separator 3 Be Further details of the method for exhaust gas aftertreatment can be obtained from the above description of the exhaust gas aftertreatment system of FIGS. 1 to 6 according to the invention.

1 Internal combustion engine
2 Exhaust gas post-treatment system
Three particle separator
4 Exhaust gas supply line
5 Exhaust gas discharge line
6 Granule feed section
7 Granule discharge part
8 separation devices
9 Ash and soot particles
10 Particulate Matter Purified
11 stages
12 stages
13 granular body
14 granular body
15 oxidation catalytic converter
16 Oxidizer
17 Ash
18 carbon dioxide
19 Oxidation catalytic converter
20 turbines
21 Oxidation catalytic converter
22 shut off valve
23 shutoff valve
24 Exhaust gas flow

Claims (14)

An exhaust gas aftertreatment system (2) for an internal combustion engine (1),
A particle separator (3) arranged downstream of an internal combustion engine (1) for removing soot or ash particles from exhaust gas in the form of a moving bed reactor or fluidized bed reactor containing particulate matter, said The exhaust gas to be purified in the particle separator (3) may be supplied to the particle separator (3) via at least one exhaust gas supply line (4) and purified in the particle separator (3) The exhaust gas can be discharged from the particle separator (3) via at least one exhaust gas discharge line (5), the granules (13, 14) comprising at least one granule supply (6) Can be fed to the particle separator (3) via the at least one particle outlet (7) and the particles (13, 14) can be discharged from the particle separator (3), the particles The exhaust gas in the separator (3) flows around the granules (13, 14), and in the process soot and ash particles adhere to the granules (13, 14), And / or the particulates bound to the particulates (13, 14) and / or reacted with the particulates (13, 14), together with the soot and ash particles and / or their reaction products A particle separator (3) , wherein (13, 14) may be discharged from said particle separator (3) via at least one said particulate discharge (7);
For separating the soot and ash particles released from the particle separator (3) and / or the reaction product thereof from the particulate (13, 14) together with the particulate (13, 14), and the soot And at least partial return of the particles separated from the ash particles and / or from the reaction product thereof into the particle separator (3) via the at least one particle feed (6) of the particle separator and (3) assigned to the separation device (8) possess Therefore,
The exhaust gas aftertreatment system comprises an oxidation catalytic converter (19) arranged upstream of the particle separator (3) and downstream of the internal combustion engine (1) for the oxidation of SO ₂ to SO ₃ In addition,
SO ₃ and / or the exhaust gas aftertreatment system for condensing H ₂ SO ₄ is applied for direct oxidation of soot of said particle separator (3) in an internal combustion engine (1) (2).   The exhaust gas post-treatment system according to claim 1, characterized in that the granules are made of cordierite, granite, corundum, silicon carbide, aluminum oxide or metal material.   The exhaust gas may flow continuously through the particle separator (3), and the particulates may be supplied to the particle separator (3) continuously or periodically, from the particle separator (3) continuously The exhaust gas aftertreatment system according to claim 1, characterized in that the exhaust gas can be exhausted periodically or periodically.   Cross-flow moving bed reactor or fluidized bed of exhaust gas and granules (13, 14) such that the particle separator (3) passes the exhaust gas horizontally through the particle separator (3) 4. The exhaust gas aftertreatment system according to claim 1 or 3, characterized in that it is designed as a reactor and the direction of movement or flow of the particles travels in a vertical direction intersecting the flow direction of the exhaust gas. Wherein as the particulate material supply part (6) and the granulate discharge section (7) the direction of movement or flow of the granulate (13, 14) between is carried out in the vertical direction from top to bottom, the granulate is (13, 14) is supplied to the particle separator (3) through said from the upper granular material feeding portion (6) obtained, the particle separator through the granulate discharge portion (7) from the bottom Exhaust gas aftertreatment system according to claim 4, characterized in that it can be discharged from the vessel (3).   The particle separator (3) is embodied in multiple stages, and the exhaust gas flows continuously through the individual stages (11, 12) of the particle separator (3), the individual stages (11) , 12) the chemical composition of the granules (13, 14) and / or the size of the granules (13, 14) and / or the velocity of movement or flow of the granules (13, 14) And / or an exhaust gas post-treatment system according to any of the preceding claims, characterized in that the flow rates of the exhaust gases are offset from one another.   7. The method according to claim 1, wherein the granules (13, 14) of at least one stage (11, 12) of the particle separator (3) are catalytically active. Exhaust gas post-treatment system as described in.   8. The method according to claim 1, wherein the granules (13, 14) of at least one stage (11, 12) of the particle separator (3) are catalytically inactive. An exhaust gas post-treatment system according to claim 1. The oxidation catalytic converter (19) comprises vanadium and / or potassium and / or sodium and / or iron and / or iron and / or cerium and / or cesium as active ingredients for the oxidation of SO ₂ to SO ₃ And / or oxides of these elements, wherein the oxidation catalytic converter preferentially utilizes, as a base material, titanium oxide and / or silicon oxide stabilized by tungsten oxide. An exhaust gas post-treatment system according to any one of the preceding claims. The oxidation catalytic converter (19) is characterized in that it comprises, as active component , vanadium in an amount by weight to the total of more than 5%, preferably more than 7%, particularly preferably more than 9%. The exhaust gas post-treatment system according to any one of Items 1 to 9 . Downstream of the oxidation catalytic converter (19), in the region of the particle separator (3), the mass ratio between SO ₃ and soot is at least 7: 1, preferably at least 12: 1, particularly preferably at least 16: characterized by comprising a 1, the exhaust gas after-treatment system according to any one of claims 1 to 10. Upstream of the particle separator (3), downstream of the internal combustion engine (1) is the oxidation catalytic converter (21) is arranged for the oxidation of NO to NO _2, the NO ₂ is the particle separator (3) the oxidation catalytic converter (21) serving for the oxidation of soot in the soot and for the oxidation of NO to the NO ₂ , the oxidation catalytic converter (for the oxidation of SO ₂ to the SO ₃ ( are connected in parallel to the 19), characterized in that can be blocked from the exhaust gas stream through a shut-off valve (23), an exhaust gas aftertreatment system according to any one of claims 1 to 11. Said separation device (8), wherein on the one hand an oxidizing agent for the oxidation of soot can be supplied, on the other hand the soot and ash particles separated from the granules in the separation device (8) can be supplied. characterized by a reactor of disposed downstream (15), an exhaust gas aftertreatment system according to any one of claims 1 to 12. A method for the exhaust gas post-treatment of exhaust gas leaving an internal combustion engine, wherein the exhaust gas stream is conducted through a particle separator in the form of a particulate-containing moving bed reactor or fluidized bed reactor and is particulate The soot and ash particles and / or their reaction products discharged from the particle separator together with the body are separated from the granules in a separation device and separated from the soot and ash particles and / or their reaction products The method according to any one of the preceding claims , wherein the particulates being stored are at least partially returned to the particle separator , the method being carried out with the aid of an exhaust gas aftertreatment system according to any one of the preceding claims .

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