AT521744B1 - Gasoline engine arrangement and method with an NSC system - Google Patents

Abstract

The invention relates to a spark-ignition engine arrangement and a method for operating the spark-ignition engine arrangement, the spark-ignition engine arrangement comprising a spark-ignition engine (1) and an exhaust gas after-treatment system (2) with a main catalytic converter (3), a spark-ignition engine particle filter (4) and a NOx storage catalytic converter (10), wherein the main catalytic converter (3) is designed or acts as a 3-way catalytic converter, with the main catalytic converter (3) being followed by the petrol engine particle filter (4), which optionally acts as a 4-way catalytic converter, with the petrol engine particle filter (4) having the NOx Storage catalytic converter (10) is arranged downstream, and where an oxidation catalytic converter (18) is optionally arranged upstream of the NOx storage catalytic converter (10), with a heating element (11), in particular a catalytically coated one, for heating in the front area of the NOx storage catalytic converter (10). of the NOx storage catalyst (10) is provided, the heating element (11) being arranged after the Otto particle filter (4).

Description

description

GASOLINE ENGINE ARRANGEMENT AND METHOD WITH AN NSC SYSTEM

The invention relates to an Otto engine assembly and a method according to the preambles of the independent claims.

Various methods for operating an internal combustion engine are known from the prior art, for example operation within a lambda window around A=1, which can optionally be interrupted by unfired overrun phases.

[0003] Methods are known, for example, in which the nitrogen oxides emitted by a diesel engine, in particular in the form of nitrogen dioxide NO», are stored at least temporarily in a NOx storage catalytic converter, a so-called NSC. Such NOx storage catalysts can include, for example, heavy alkali metals (e.g. potassium, sodium), heavy alkaline earth metals (e.g. barium, calcium) or light rare earths (e.g. lanthanum, cerium) in the form of the oxide or the carbonate as storage materials.

[0004] These storage materials make it possible to at least temporarily store the nitrogen oxides contained in the exhaust gas in the NOx storage catalytic converter. In order to enable the storage of nitrogen oxides, in particular in the form of nitrogen dioxide NO», an excess of oxygen is required in the exhaust gas, which is guaranteed with a conventional diesel arrangement. In order to release and reduce the stored nitrogen dioxide again, the state-of-the-art engine has to be operated sub-stoichiometrically in defined phases.

Methods for operating a diesel engine are also known in which an oxidation catalyst coated with an oxidation catalyst coating is provided, the oxidation catalyst coating being set up to convert nitrogen monoxide NO with oxygen 0>» to form nitrogen dioxide NO2. As a result, NO » is generated in or on the oxidation catalytic converter coating as soon as NO and O » » are supplied to it.

Furthermore, methods for operating a diesel or Otto engine are known in which the particle-laden exhaust gas is filtered when penetrating a porous filter wall of an exhaust gas filter. During the filtration process, particles are retained by the filter medium of the exhaust gas filter and are deposited on it.

The filter walls of the exhaust gas filter can consist of different porous materials and can be made up of fibers or powder, for example. The fibers or the powder itself consist in particular of ceramics or metals. Classic ceramics are mullite, cordierite, silicon carbide (SiC) and aluminum titanate.

[0008] Quite generally, as a result of the particles being deposited on the surface or inside the filter wall, a layer of particles affecting the filtration can form - a so-called filter cake in the case of formation on the surface, which on the one hand leads to the preferably already load-free The best possible filtration efficiency is further improved, on the other hand the flow resistance and thus also the differential pressure generated by the exhaust gas volume flow at the exhaust filter increase.

As already known from conventional diesel systems, a regeneration of the exhaust gas filter is also necessary in the Otto engine arrangement in the case of a correspondingly high soot load in order to be able to reduce or prevent excessive back pressure or unwanted temperature peaks that endanger components when the soot burns off in the particle filter. Since a gasoline engine arrangement has a significantly lower raw particle emission level in comparison to a diesel arrangement in combination with a significantly higher exhaust gas temperature level, regeneration of the gasoline engine arrangement is necessary less often.

[0010] The active initiation of the regeneration of the gasoline engine particulate filter is also necessary in the gasoline engine arrangement at the latest when the exhaust gas

gendruck exceeds an exhaust gas back pressure threshold value, at which the exhaust gas emissions are severely impeded and, in particular, component limit values of the engine or the exhaust gas aftertreatment system that are potentially relevant to long-term damage are exceeded.

In conventional Otto engine configurations, on the one hand, the exhaust gas temperature is higher than in conventional diesel configurations, making thermal-oxidative regeneration easier in the presence of oxygen. On the other hand, in comparison to conventional diesel configurations, less oxygen is produced in conventional Otto engine configurations due to normal stoichiometric operation, as a result of which significantly less oxygen is available for regeneration of the Otto engine particle filter.

[0012] Further Otto engine arrangements are known, for example, from US 2009193796 A1, US 2003131593 A1, WO 2007113677 A1 and EP 3115566 A1.

It is an object of the invention to overcome the disadvantages of the prior art. In particular, the object of the invention is to create a gasoline engine arrangement in order to further reduce or lower the already low nitrogen oxide level after the at least one main catalytic converter, in particular the 3-way catalytic converter, as far as possible, in particular in the direction of immission ambient air limit values. It is therefore the object of the invention to come closer to the so-called vision of "zero impact emissions" in order to provide the end customer with an economical petrol engine arrangement on the one hand and on the other hand to protect the environment by falling below the pollutant emission laws prescribed by the legislator as far as possible.

The object according to the invention is achieved in particular by the features of the independent patent claims.

The invention relates to a spark-ignition engine arrangement, the spark-ignition engine arrangement comprising a spark-ignition engine and an exhaust gas after-treatment system with at least one main catalytic converter, a spark-ignition engine particle filter and a NOx storage catalytic converter, the main catalytic converter being designed or acting as a 3-way catalytic converter, and the main catalytic converter being Gasoline engine particle filter, which optionally acts as a 4-way catalyst, is downstream.

According to the invention, it is provided that the NOx storage catalytic converter is arranged downstream of the Otto engine particle filter and that, if necessary, a further catalytic converter, in particular an oxidation catalytic converter, is arranged in front of the NOx storage catalytic converter and that a heating element, in particular a catalytically coated one, is arranged in the front area of the NOx storage catalytic converter Heating of the NOx storage catalytic converter is provided, the heating element being arranged after the Otto particle filter (4).

The Otto engine arrangement can be the Otto engine arrangement of an internal combustion engine, in particular the Otto engine arrangement of a motor vehicle.

[0018] The Otto engine arrangement comprises a Otto engine and an exhaust gas aftertreatment system. The exhaust gas aftertreatment system includes a main catalytic converter, in particular a 3-way catalytic converter, a gasoline engine particle filter arranged downstream of the main catalytic converter and a NOx storage catalytic converter arranged downstream of the petrol engine particle filter.

Optionally, the NOx storage catalytic converter is positioned at a position in the exhaust aftertreatment system in which the exhaust gas temperature has a lower temperature when it enters the NOx storage catalytic converter than when it exits the gasoline engine.

Furthermore, the exhaust aftertreatment system can include the main catalytic converter(s), the gasoline engine particulate filter and the NOx storage catalytic converter and optionally one or more primary catalytic converter(s) and/or one or more secondary catalytic converter(s), in particular one or more oxidation catalytic converter(s), which/r an oxidation catalytic converter coating/s, and/or one or more heated catalytic converter/s and/or one or more gasoline engine particulate filters coated in particular in gaseous form with effective exhaust gas aftertreatment and/or one or more NOx storage catalytic converters and/or one or more exhaust gas aftertreatment components /n, which include a NOx storage catalyst coating, and / or

one or more SCR system(s) and/or one or more exhaust gas aftertreatment component/s, which include an SCR coating, and/or include a secondary air injection system.

Furthermore, the exhaust aftertreatment system can consist of the main catalytic converter(s), the gasoline engine particle filter and the NOx storage catalytic converter and optionally one or more primary catalytic converter(s) and/or one or more secondary catalytic converter(s), in particular one or more oxidation catalytic converter(s), which/ r comprises an oxidation catalytic converter coating/s, and/or one or more heated catalytic converter/s and/or one, in particular one or more gaseous exhaust gas aftertreatment-effectively coated, gasoline engine particulate filter/s and/or one or more NOx storage catalytic converter/s and/or one or several exhaust gas aftertreatment component/s, which includes a NOx storage catalyst coating/s, and/or one or more SCR system/s and/or one or more exhaust gas aftertreatment component/s, which includes an SCR coating/s, and/or one Secondary air injection be formed.

In a preferred embodiment, the gasoline engine particle filter and the NOx storage catalyst are provided on a common carrier body. In a further preferred embodiment, the gasoline engine particle filter and the NOx storage catalytic converter are provided on two carrier bodies arranged one behind the other. This makes it possible to decouple the two exhaust gas aftertreatment components, in particular thermally. In particular, provision can be made for the two exhaust gas aftertreatment components to be arranged in a housing, in particular in a steel housing, in order to enable a compact design.

In particular, the exhaust gas generated in the gasoline engine flows through the main catalytic converter, then through the additional catalytic converter that may be provided, in particular the oxidation catalytic converter, through the gasoline engine particle filter and then through the NOx storage catalytic converter of the exhaust gas aftertreatment system.

Since the NOx storage catalytic converter is arranged after the main catalytic converter and after the gasoline engine particle filter, the NOx storage catalytic converter can be protected from high exhaust gas temperatures, which occur in particular in areas of the exhaust gas aftertreatment system close to the engine.

[0025] This means that the exhaust gas emitted by the gasoline engine may cool down as it flows through the exhaust gas aftertreatment system and the exhaust gas aftertreatment components arranged in the exhaust gas aftertreatment system. As a result, the exhaust gas flows through the NOx storage catalytic converter at a lower temperature than the entry temperature into the exhaust aftertreatment system. As a result, on the one hand thermal stresses, but in particular also thermal aging effects in the NOx storage catalytic converter can be reduced and/or prevented, as a result of which the service life of the NOx storage catalytic converter can be increased, in particular maximized.

If necessary, oxygen, in particular air, is supplied to the additional catalytic converter that may be provided, in particular to the oxidation catalytic converter and the NOx storage catalytic converter. In this so-called storage mode, the nitrogen oxides emitted by the gasoline engine, in particular in the form of nitrogen dioxide NO», can be stored at least temporarily and, if necessary, the stored nitrogen oxides can be converted back to nitrogen N» if the NOx storage catalytic converter or the exhaust gas flowing through the NOx storage catalytic converter Has a temperature which is greater than a storage temperature, in particular greater than 100° C., preferably greater than 180° C. It is stated here that with the different NOx storage catalytic converter coating technologies, a different “light off” storage temperature required for storage must be reached. Subsequently, the storage temperature should exceed a maximum value as little as possible in order not to drop out of a so-called storage window again.

[0027] Furthermore, the Otto engine arrangement according to the invention makes it possible to store the nitrogen oxides emitted by the Otto engine in the form of NO in the NOx storage catalytic converter and to store these

subsequently converted into water, carbon dioxide and nitrogen, for example.

If, for example, barium Ba is used as a storage material in the NOx storage catalytic converter, the nitrogen oxides emitted by the gasoline engine are stored essentially according to the following rule:

1 BaCO, + 2N0, +5 02 > Ba(NO3)2 + CO,

It may also be possible that the stored nitrogen dioxide is released again by the supply of carbon monoxide CO and/or hydrocarbon HC and the resulting decomposition of the nitrate. If, for example, barium Ba is used as storage material, this withdrawal essentially takes place according to the following rule:

Ba(NO2)> + CO » BaCOz +2 NO + 0,

The resulting nitrogen monoxide NO can be reduced to nitrogen N» by a reducing agent such as hydrocarbon HC, hydrogen H2 or carbon monoxide CO on a noble metal component of the NOx storage catalytic converter, in particular on rhodium Rh. This reduction is essentially based on the following rule:

1HC +2 NO +02 +5 H2 + CO > H20 +2CO2 + N;

It is preferably provided that a catalytic converter coated with an oxidation catalytic converter coating is provided in the front region of the NOx storage catalytic converter or in front of the NOx storage catalytic converter. This oxidation catalytic converter coating can be set up to convert NO with O » to NO ». This conversion essentially takes place according to the following rule:

2NO0 +0, > 2N0,

The oxidation catalyst coating preferably comprises a platinum metal, such as in particular platinum, rhodium and/or palladium, or is formed from a platinum metal, such as in particular platinum, rhodium and/or palladium.

Furthermore, this oxidation catalytic converter coating can be set up to absorb NH which may be formed as a by-product and intermediate product of catalytic reactions in the catalytic converters in the presence of CO; with O2» to NOx. This conversion essentially takes place according to the following rule:

4NHz3z + (3 + 2x)0, > 4N0, + 6H,0 where x = {1,2}

In particular, the oxidation catalyst with oxygen can minimize or reduce any NH3 formed. The resulting reaction products, in particular the nitrogen oxides, can then be fed to a NOx aftertreatment system that is preferably as effective as possible, such as a NOx storage catalytic converter.

This makes it possible to oxidize by-products and intermediate products of catalytic reactions, for example NHe, in the catalytic converters, in particular in the oxidation catalytic converter, and to supply the reaction products produced during this oxidation in the oxidation catalytic converter, in particular the nitrogen oxides, to the best possible NOx aftertreatment. In particular, it is possible that in the main catalytic converter, in particular in the 3-way catalytic converter, NH; formed when CO or H2 is present in the exhaust gas.

In order to store nitrogen oxides in the NOx storage catalytic converter, it can be provided that both the NOx storage catalytic converter and the oxidation catalytic converter coating are supplied with oxygen and, in particular, air. As a result, nitrogen monoxide can be reacted with oxygen to form nitrogen dioxide in a first step, and the nitrogen dioxide produced in this way can be stored in the NOx storage catalytic converter in a second step.

In the context of the present invention, the at least one main catalyst or the main catalyst includes one or more catalyst(s), in particular a plurality of main catalysts.

Iysatoren to understand, which essentially have the same effect and / or function. If appropriate, the at least one main catalytic converter comprises one or more catalytic converter(s), in particular one or more primary or secondary catalytic converter(s) and/or one or more heated catalytic converter(s). The at least one main catalytic converter may be formed from one or more main catalytic converter(s), in particular from one or more primary and/or secondary catalytic converter(s) and/or from one or more heated catalytic converter(s). At least one of the abovementioned catalysts is preferably coated with a 3-way coating.

If necessary, it is provided that the Otto engine is designed as an Otto engine regulated in a lambda window by )=1 in front of the exhaust gas aftertreatment system.

In the normal operating phase, which essentially corresponds to the regular operating mode of the Otto engine arrangement or the Otto engine, fuel and air are introduced into the combustion chamber of at least one cylinder of the Otto engine and converted to exhaust gas by combustion.

In the normal operating phase, the Otto engine can preferably be operated and/or regulated in a lambda window around )=1. This means that the Otto engine is optionally operated oscillating around a lambda value X of 1.0 and in particular operated and/or regulated with a lambda value A in the range from 0.9 to 1.1, preferably from 0.95 to 1.05 becomes. Provision can be made for the Otto engine to be operated and/or controlled in its normal operating phase in phases or permanently substoichiometrically or overstoichiometrically or richly or leanly, provided that the exhaust gas aftertreatment components of the Otto engine arrangement allow a sufficiently high, in particular the best possible, raw emission conversion under these conditions.

This may mean that in the normal operating phase, in the storage mode of the NOx storage catalytic converter and/or in the regeneration mode of the gasoline engine particle filter, a sufficient, preferably the greatest possible, degree of conversion of the pollutants by the exhaust gas aftertreatment components should be ensured overall. As a result, a sufficiently high reduction in pollutants can be made possible in both operating phases. In particular, it is provided that the pollutant emission conversion level of the exhaust gas aftertreatment system never falls below a pollutant emission conversion level threshold value, below which a sufficiently high pollutant emission reduction is no longer given. If necessary, provision is made for the pollutant emission conversion efficiency threshold to be as high as possible, in particular in a range as close to 100% as possible.

In particular, it is provided that the exhaust gas generated by the gasoline engine is essentially oxygen-free in the normal operating phase and contains at most only small amounts of oxygen.

If necessary, it is provided that the gasoline engine particulate filter has the oxidation catalytic converter, in particular in its front area, with the oxidation catalytic converter being applied in particular in the direction of flow of the exhaust gas from the front of the gasoline engine particulate filter, and/or that the NOx storage catalytic converter, in particular in its front Area that has the oxidation catalytic converter and/or that the oxidation catalytic converter is provided between the main catalytic converter and the gasoline engine particle filter and/or that the oxidation catalytic converter is provided between the gasoline engine particle filter and the NOx storage catalytic converter, the oxidation catalytic converter being a platinum metal, preferably platinum, rhodium and/or palladium , includes.

Optionally, it is provided that the oxidation catalytic converter has an oxidation catalytic converter coating, acts as an oxidation catalytic converter and/or is formed from an oxidation catalytic converter coating.

The oxidation catalyst coating comprises an element of the platinum group metals or platinoids or is made from an element of the platinum group metals or platinoids such as, in particular, platinum,

rhodium and/or palladium. In English, platinum metals or platinoids are also referred to as Platinum Group Metals (PGM).

The oxidation catalytic converter coating is designed to convert nitrogen monoxide NO with oxygen O» to form nitrogen dioxide NO». Preferably, NO is reacted with O » to NO » in or on the oxidation catalytic converter coating.

The particles emitted by the Otto engine, in particular the soot emitted by the Otto engine and/or the ash emitted by the Otto engine, are filtered by the Otto engine particle filter. The petrol engine particle filter is loaded with the particles emitted by the petrol engine.

If necessary, the cleaning performance and/or the particle separation performance of the petrol engine particle filter is increased by the particle residue from the retained particles during filtration on the petrol engine particle filter, as a result of which the petrol engine particle filter has its preferably greatest possible basic filtration efficiency defined by the substrate and coating. Furthermore, the spark-ignition engine particle filter exhibits its preferably greatest possible normal filtration efficiency after a certain particle loading, in particular after a so-called preferably lowest possible basic loading. In addition, what is known as a filter cake can form in the gasoline engine particle filter, in particular if the gasoline engine particle filter is loaded with large amounts of particles or large amounts of ash.

If necessary, the regeneration in the normal operating phase, in particular the soot oxidation processes, takes place only slowly or not at all in large parts. The deceleration is mostly due to the lower oxygen content, in particular to the lower amount of oxygen, which flows through the gasoline engine particle filter in the normal operating phase. The lower the amount of oxygen introduced per unit of time, the slower the soot oxidation processes and thus the regeneration of the gasoline engine particle filter can take place.

According to a preferred embodiment, it is provided that the oxidation catalytic converter coating is set up to convert nitrogen monoxide NO with oxygen O» to form nitrogen dioxide NO». As a result, NO» can be generated in or on the oxidation catalyst coating as soon as NO and O> are supplied to it. The reaction of nitrogen monoxide with oxygen to form nitrogen dioxide essentially takes place according to the following rule:

1 NO +50; > NO,

[0051] Nitrogen dioxide NO» makes it possible to at least partially oxidize the soot particles, in particular the carbon C, located in the gasoline engine particle filter. This may make it possible to regenerate the gasoline engine particle filter. Soot oxidation essentially takes place according to the following rule:

2N02+C > 2N0+CO-,

The nitrogen dioxide NO » not converted by the gasoline engine particle filter can be taken up in a further step by the NOx storage catalytic converter arranged after the gasoline engine particle filter and/or optionally converted to water, carbon dioxide and nitrogen.

In a further step, the nitrogen monoxide NO produced by the gasoline engine particle filter can be further oxidized and absorbed by the NOx storage catalytic converter arranged after the gasoline engine particle filter to form nitrogen dioxide NO » and/or possibly converted to water, carbon dioxide and nitrogen.

In particular, the regeneration temperature required for the soot oxidation processes when using nitrogen dioxide NO » is significantly lower than the regeneration temperature required for the soot oxidation processes when using oxygen O ».

[0055] For example, the gasoline engine particulate filter is regenerated by the introduction of nitrogen dioxide NO » if the gasoline engine particulate filter itself, the exhaust gas flowing through the gasoline engine particulate filter and/or the particles located in the gasoline engine particulate filter has or have a temperature which is greater than a regeneration temperature. Especially

the Otto engine particle filter can already be regenerated at a regeneration temperature of less than 600° C., in particular less than 500° C., preferably between 200° C. and 500° C.

By using nitrogen dioxide-based regeneration, the so-called passive regeneration, and thus the lower temperatures occurring in the gasoline engine particulate filter, it is possible to increase, in particular to maximize, the thermal and/or thermo-mechanical aging resistance of the gasoline engine particulate filter in terms of sustainability .

[0057] Furthermore, it may be possible to reduce the quantity of particles in the gasoline engine particle filter without an active heating measure and/or without further CO emissions occurring. In particular, this makes it possible to keep the gasoline engine particle filter at a low loading level, but at least one that is suitably high for maximum filtration efficiency requirements, in the sense of minimizing emissions.

Furthermore, due to the lower regeneration temperature, a NOx storage catalytic converter that may be arranged after the gasoline engine particle filter can be operated in its optimum temperature window, in particular below 500° C. and preferably in a temperature range between 250° C. and 450° C.

If necessary, it is provided that the gasoline engine particulate filter includes the NOx storage catalytic converter, with the NOx storage catalytic converter being arranged in the rear area of the gasoline engine particulate filter, and/or that the gasoline engine particulate filter has a coating that acts as a NOx storage catalytic converter and/or that the NOx -A coating that acts as a storage catalyst is applied from the back of the gasoline engine particle filter in the flow direction of the exhaust gas, the coating that acts as a NOx storage catalyst in particular comprising a barium component, preferably barium oxide, barium carbonate and/or a cerium oxide component.

If necessary, it is provided that there is a supply line that opens into the exhaust aftertreatment system between the main catalytic converter and the additional catalytic converter, in particular the oxidation catalytic converter, between the main catalytic converter and the gasoline engine particle filter and/or between the gasoline engine particle filter and the NOx storage catalytic converter, and that the supply line to Supply of oxygen and in particular air is set up in the exhaust aftertreatment system and is flowed through in particular unidirectionally.

[0061] An oxygen-containing gas, in particular air, can be fed through the feed line to the Otto engine particle filter, the NOx storage catalytic converter and/or the further catalytic converter, in particular the oxidation catalytic converter.

In all embodiments, this means that this oxygen-containing gas, in particular the air, subsequently flows through the optionally present oxidation catalytic converter or a coating acting as an oxidation catalytic converter, optionally the Otto engine particle filter and the NOx storage catalytic converter.

[0063] By supplying oxygen, on the one hand the gasoline engine particle filter can be regenerated and/or on the other hand the nitrogen oxides can be stored and/or converted. When oxygen is supplied, the gasoline engine particle filter can be operated in its regeneration mode and/or the NOx storage catalytic converter can be operated in its storage mode.

If necessary, provision is made to regenerate the gasoline engine particle filter by supplying oxygen. This so-called active regeneration through the supply of oxygen can lead to at least partial combustion of the particles stored in the gasoline engine particle filter. The temperature during active regeneration can be above 500°C, preferably above 600°C.

If necessary, provision is made to generate nitrogen dioxide NO» by supplying oxygen upstream of the gasoline engine particle filter and to generate the gasoline engine particle filter through the supply

of the produced NO» to regenerate. This so-called passive regeneration through the supply of nitrogen dioxide can lead to at least partial oxidation of the particles stored in the gasoline engine particle filter. The temperature during passive regeneration can be below 500°C, preferably between 200°C and 500°C.

If necessary, provision is made for the NOx produced and/or the existing NO to be stored at least temporarily in the NOx storage catalytic converter by supplying oxygen upstream of the NOx storage catalytic converter and, if appropriate, subsequently to convert the stored NO” into water, carbon dioxide and nitrogen.

Provision is preferably made for oxygen-containing gas, in particular air, to flow through only the oxidation catalytic converter, which may be arranged upstream of the spark-ignition engine particle filter or upstream of the NOx storage catalytic converter, the spark-ignition engine particle filter and/or the NOx storage catalytic converter when oxygen-containing gas is supplied through the supply line 0who will.

In contrast to conventional methods, it is not necessary to periodically operate the gasoline engine lean or rich, since oxygen and in particular air is supplied to the optionally provided oxidation catalytic converter, the gasoline engine particle filter and/or the NOx storage catalytic converter via the supply line. In contrast to methods known from the prior art, it may be possible to operate and/or regulate the Otto engine, in particular always, in a lambda window around )=1. As a result, it may be possible for essentially always an essentially oxygen-free or low-oxygen exhaust gas to be supplied to the 3-way catalytic converter and the other exhaust gas aftertreatment components acting as a 3-way catalytic converter.

During the supply of air, the oxygen content of the exhaust gas flowing through the main catalytic converter or of the exhaust gas located in the main catalytic converter can be less than 5% by volume or essentially zero.

During the supply of air, the amount of oxygen in the exhaust gas flowing through the main catalytic converter or the amount of oxygen in the exhaust gas located in the main catalytic converter can therefore be kept so low that the efficiency of the main catalytic converter and/or, if appropriate, the pre-catalyst or secondary or heated catalytic converter is unaffected, so that at all times a sufficiently high, preferably the best possible, degree of pollutant emission conversion of the exhaust gas aftertreatment components is ensured overall.

In particular, the main catalytic converter, the main catalytic converters or the main catalytic converter(s) and the other exhaust gas aftertreatment components before the supply line opens into the exhaust gas aftertreatment system have a high, preferably best possible, efficiency in both normal and storage mode.

It may thereby be possible to store the nitrogen oxides emitted by the Otto engine in the form of NOx in the NOx storage catalytic converter without having to flood the exhaust gas aftertreatment system, in particular the main catalytic converter, with oxygen.

If necessary, storage operation is interrupted after the maximum possible storage of NOx in the NOx storage catalytic converter.

If necessary, it is provided that the Otto engine arrangement comprises a supply line that opens into the exhaust aftertreatment system, that the supply line opens into the exhaust aftertreatment system before the gasoline engine particle filter, before the NOx storage catalytic converter and/or before the additional catalytic converter that may be provided, in particular the oxidation catalytic converter, with the Feed line branches off between a compressor and an intercooler of the turbocharger, or the feed line branches off between an intercooler of the turbocharger and the Otto engine, or the feed line for introducing air from the environment outside the Otto engine arrangement to the ambient air, in particular unidirectionally, is open.

[0075] When supplying oxygen-containing gas to the exhaust gas aftertreatment system

through the supply line, air from the environment flows through the compressor of the turbocharger, optionally through the intercooler of the turbocharger, through the supply line and then through the gasoline engine particle filter, through the NOx storage catalytic converter and/or through the additional catalytic converter that may be provided, in particular the oxidation catalytic converter.

In particular, it is provided that air compressed by the compressor of the turbocharger enters the supply line after the compressor of the turbocharger or possibly after the intercooler of the turbocharger and before the additional catalytic converter that may be provided, in particular before the oxidation catalytic converter, before the gasoline engine particle filter and/or before exits the NOx storage catalytic converter from the feed line.

When oxygen-containing gas is supplied to the exhaust gas aftertreatment system, air can flow through the supply line and then through the gasoline engine particle filter, through the NOx storage catalytic converter and/or through the additional catalytic converter that may be provided, in particular the oxidation catalytic converter.

In particular, it is provided that uncompressed air, in particular uncompressed ambient air, enters the supply line and exits from the supply line upstream of the additional catalytic converter that may be provided, in particular the oxidation catalytic converter, upstream of the gasoline engine particle filter and/or upstream of the NOx storage catalytic converter.

If necessary, it is provided that a venturi nozzle is provided for introducing the ambient air of the supply line into the exhaust gas aftertreatment system and that the venturi nozzle opens into the exhaust gas aftertreatment system before the gasoline engine particle filter.

In particular, it can be provided that one end of the feed line opens into the environment, in particular outside of the exhaust gas aftertreatment system, and the other end into the exhaust gas aftertreatment system. Furthermore, it can be provided that the supply line is unidirectionally flown in the direction of the exhaust gas aftertreatment system.

In particular, it can be provided that the supply line into the exhaust gas aftertreatment system includes a safety device, such as in particular a check valve or a membrane, which prevents the exhaust gas from escaping into the environment or into other components of the exhaust gas aftertreatment system.

[0082]Furthermore, a negative pressure can exist or arise in the exhaust gas aftertreatment system when exhaust gas flows through the exhaust gas aftertreatment system. It can therefore be possible that this negative pressure means that air from the environment is sucked through the supply line into the exhaust gas aftertreatment system and is preferably introduced into the exhaust gas aftertreatment system upstream of the gasoline engine particle filter, upstream of the NOx storage catalytic converter and/or upstream of the additional catalytic converter that may be provided, in particular the oxidation catalytic converter becomes.

In particular, the ambient air can be introduced into the exhaust gas aftertreatment system via a Venturi nozzle. If necessary, it is provided that the exhaust gas after-treatment system and/or the supply line is/are designed as a Venturi nozzle in the area in which the supply line opens into the exhaust gas after-treatment system.

If necessary, it is provided that a controllable and/or regulatable blower for conveying the oxygen, in particular for conveying the air, is provided on the supply line, which is in particular unidirectional, and/or that a supply valve is provided along the supply line, with the Supply valve is set up for controlling the amount of oxygen or air that is supplied to the gasoline engine particle filter, the NOx storage catalytic converter and/or the additional catalytic converter that may be provided, in particular the oxidation catalytic converter.

If necessary, it is provided that the supply line has a controllable and/or adjustable blower for conveying the oxygen, in particular for conveying the air, in particular

Special to promote the optionally filtered ambient air includes.

If necessary, it is provided that the supply line comprises a pressure reservoir, in particular a compressed air reservoir, for storing and/or conveying the oxygen, in particular for storing and conveying the air, in particular for storing and conveying the ambient air, which may have been filtered.

If necessary, a pressure accumulator can be filled continuously or discontinuously by the blower and is arranged in the supply line between a blower and the point at which the supply line opens into the exhaust gas aftertreatment system.

The controllable and/or regulatable blower can be designed as a mechanical compressor and/or electric compressor.

If necessary, it is provided to introduce air from the air-filled pressure accumulator into the exhaust gas aftertreatment system via the supply line.

The controllable and/or regulatable blower can control the delivery rate of the oxygen, in particular the delivery rate of the air, which is introduced through the supply line into the exhaust gas aftertreatment system, in particular upstream of the gasoline engine particle filter, upstream of the NOx storage catalytic converter and/or upstream of the oxidation catalytic converter , controlled and/or regulated.

If necessary, it is provided that the NOx storage catalytic converter is the last catalytic converter of the exhaust gas aftertreatment system in the flow direction of the exhaust gas.

Optionally, it is provided that the gasoline engine particulate filter is uncoated or designed as a 2-way catalytic converter or as a 3-way catalytic converter or as a 4-way catalytic converter, or that the gasoline engine particulate filter has no catalytic converter or a 2-way catalytic converter or a 3-way Catalyst or a 4-way catalyst includes.

It can be provided that the Otto engine particle filter is uncoated in one embodiment and is set up exclusively to filter particles.

It can be provided that the gasoline engine particle filter is set up to filter particles and additionally convert and/or store hydrocarbons, carbon monoxide and/or nitrogen oxides, optionally or in combination. As a result, the gasoline engine particle filter is designed as a 2-, 3- or 4-way catalytic converter, depending on the coating.

It can be provided that the gasoline engine particle filter is set up to filter particles, to store NOx and to convert hydrocarbons, carbon monoxide and nitrogen oxides. As a result, the gasoline engine particulate filter is designed as a 4-way catalytic converter with a storage function.

If necessary, it is provided that after the Otto engine and before the main catalytic converter, in particular in the front area of the main catalytic converter, a heating element, in particular catalytically coated, is provided for heating the main catalytic converter and/or that after the Otto engine, in particular after the main catalytic converter, and upstream of the oxidation catalytic converter, in particular in the front area of the oxidation catalytic converter, a heating element, in particular catalytically coated, for heating the oxidation catalytic converter is provided and/or downstream of the gasoline engine, in particular downstream of the oxidation catalytic converter, and in front of the gasoline engine particulate filter, in particular in the front region of the gasoline engine particulate filter , In particular catalytically coated heating element, is provided for heating the gasoline engine particulate filter.

The heating elements can be fed by the vehicle electrical system, which in particular has a nominal voltage of 12 volts or 48 volts.

If necessary, it is provided that at least one heating element is provided in front of each exhaust gas aftertreatment component of the exhaust gas aftertreatment system, in particular in the front area of each exhaust gas aftertreatment component. For example, the respective catalysts and / or oxidation catalysts and / or gasoline engine particle filter and / or

all other components of the exhaust aftertreatment system reach the functional temperature (light-off temperature) required for their efficient function earlier thanks to the heating elements.

According to the invention, a heating element is provided in front of the NOx storage catalytic converter, in order to be able to quickly heat the NOx storage catalytic converter to its operating temperature, especially during a cold start of the internal combustion engine, and thus to reduce the emission of harmful, gaseous emissions such as CO, THC or NOx - Minimize emissions. Since the NOx storage catalytic converter generally requires a lower temperature for its function than the 3-way catalytic converter, the NOx emissions emitted by the gasoline engine during a cold start can be absorbed by the NOx storage catalytic converter.

It may also be advantageous for the catalytically coated heating element to be installed in front of an oxidation catalyst and/or in front of the gasoline engine particle filter, which may include an oxidation catalyst coating and/or a NOx storage catalyst function, or in front of a separate NOx storage catalyst component or in front the overall grouping of the exhaust gas aftertreatment components, is arranged in order to enable an active 3-way function as soon as possible after or preferably when the engine is started, in addition to the above-mentioned advantages relating to NOx emissions.

Furthermore, the heating elements and the heating of the individual catalysts made possible by them can be used for their desulfurization. In particular, this makes it possible to carry out desulfurization of the NOx storage catalytic converter with the heating element. Since the NOx storage catalytic converter can also be arranged as the last exhaust gas component in the exhaust gas aftertreatment system, such a desulfurization has the least thermal influence on the other exhaust gas aftertreatment components. In contrast to conventional processes, no additional fuel or only a small amount of additional fuel is required for desulfurization, and particulate emissions are also essentially not increased. The temperature required for the desulfurization, in particular the temperature window required for the desulfurization, can be above that in which storage of nitrogen oxides is possible. In order to avoid unwanted emissions of nitrogen oxides, the NOx storage catalytic converter is, if necessary, completely regenerated before desulfurization takes place.

If necessary, it is provided that the Otto engine can be operated in an operating phase, which includes a normal operating phase and an overrun phase, that the Otto engine converts fuel and air into an exhaust gas in the normal operating phase, that the Otto engine in the normal operating phase preferably converts in a lambda window A=1 is operated and/or controlled, that the overrun phase is formed by at least one unfired overrun phase and/or at least one fired overrun phase, that in the fired overrun phase the gas flowing through the main catalytic converter is low in oxygen, in particular essentially oxygen-free, and in particular the exhaust gas is a stoichiometric or sub-stoichiometric, in particular phase-wise sub-stoichiometric, combustion, with an exhaust gas recirculation line being provided that the Otto engine in an unfired overrun phase before or during the transition from the normal operating phase in the unfired exhaust gas generated in the first overrun phase in the petrol engine,

or wherein an exhaust gas recirculation line is provided, which supplies the Otto engine in an unfired overrun phase with the exhaust gas generated before or during the transition from the fired overrun phase to the unfired overrun phase in the Otto engine.

If necessary, it is provided that an oxidation catalytic converter coated with an oxidation catalytic converter coating is provided between the main catalytic converter and the gasoline engine particulate filter, or that the gasoline engine particulate filter is provided with an oxidation catalytic converter coating at least in its front region, the oxidation catalytic converter coating being added to this is set up to convert NO with O2 to NO2.

Optionally, it is provided that the Otto engine arrangement comprises a supply line which opens into the exhaust aftertreatment system, the supply line being used to supply the Otto engine particle filter, in particular for regenerating the Otto engine particle filter, and/or

oxygen and in particular air, preferably filtered ambient air, can be fed to the oxidation catalytic converter, and/or wherein oxygen and in particular air, preferably filtered ambient air, can be fed via the feed line to the NOx storage catalytic converter, in particular for storing and converting nitrogen oxides, and/or to the oxidation catalytic converter is.

In particular, it is provided to use the oxygen introduced through the supply line in combination and to operate the NOx storage catalytic converter in its storage mode on the one hand and the gasoline engine particle filter in its regeneration mode on the other hand with this oxygen. As a result, it may be possible to regenerate a gasoline engine particle filter positioned in front of the NOx storage catalytic converter in operating ranges of the gasoline engine arrangement in which regeneration could previously not take place due to a lack of oxygen.

If necessary, it is provided that the supply line bringing oxygen to the gasoline engine particle filter and the NOx storage catalytic converter opens into the exhaust gas aftertreatment system before the gasoline engine particle filter and after the main catalytic converter.

If necessary, it is provided that the exhaust gas after-treatment system comprises an SCR catalytic converter, that the SCR catalytic converter is arranged after the main catalytic converter, after the oxidation catalytic converter and/or after the gasoline engine particle filter, that the gasoline engine arrangement has a or the opening into the exhaust gas after-treatment system, in particular through which flow can flow unidirectionally, Includes supply line, and that via the supply line to the SCR catalytic converter, in particular for the reduction of nitrogen oxides, oxygen and in particular air, preferably filtered ambient air can be fed.

[00108] It is optionally provided that oxygen, in particular ambient air, is supplied to the gasoline engine particle filter, the oxidation catalytic converter, the NOx storage catalytic converter and/or the SCR catalytic converter via a supply line.

Alternatively, it is provided that oxygen, in particular ambient air, is supplied to the gasoline engine particle filter, the oxidation catalytic converter, the NOx storage catalytic converter and/or the SCR catalytic converter via a separate supply line.

If necessary, it is provided that before the SCR catalytic converter and in particular after the oxidation catalytic converter, a dosing device for introducing a fuel, in particular what is known as AdBlue®, is provided.

In particular, the invention relates to a method for operating the spark-ignition engine arrangement according to the invention, the spark-ignition engine arrangement comprising a spark-ignition engine and an exhaust gas aftertreatment system with a main catalytic converter, a spark-ignition engine particle filter and a NOx storage catalytic converter, and the exhaust gas first passes through the main catalytic converter, then the spark-ignition engine particle filter and then the Flow through NOx storage catalytic converter.

In the context of the present invention, a front region of an exhaust gas aftertreatment component is to be understood as meaning the region through which the exhaust gas flows earlier in the flow direction of the exhaust gas in the respective exhaust gas aftertreatment component. In particular, this can be the area through which the exhaust gas enters the respective exhaust gas aftertreatment component.

In the context of the present invention, a rear area of an exhaust gas aftertreatment component is understood to mean the area through which the exhaust gas later flows in the flow direction of the exhaust gas in the respective exhaust gas aftertreatment component. In particular, this can be the area through which the exhaust gas exits from the respective exhaust gas aftertreatment component.

[00114] Further features according to the invention can be found in the claims, the description of the exemplary embodiments and the figures. The invention will now be explained further using the example of exemplary, non-exclusive and/or non-limiting embodiments.

Figures 1a, 1b, 1c and 1d show schematic diagrams of variants of a

first embodiment of a gasoline engine arrangement according to the invention,

2a and 2b show schematic graphic representations of variants of a second embodiment of a spark-ignition engine arrangement according to the invention,

3 shows a schematic graphic representation of a third embodiment of a spark-ignition engine arrangement according to the invention,

4a and 4b show schematic graphic representations of variants of a fourth embodiment of a spark-ignition engine arrangement according to the invention,

5 shows a schematic diagram of a fifth embodiment of a spark-ignition engine arrangement according to the invention, and

6a to 6c show schematic graphic representations of variants of a sixth embodiment of a spark-ignition engine arrangement according to the invention.

Unless otherwise indicated, the reference symbols correspond to the following components: gasoline engine 1, exhaust gas aftertreatment system 2, main catalytic converter 3, gasoline engine particle filter 4, turbocharger 5, throttle valve 6, compressor 7, turbine 8, exhaust gas recirculation line 9, NOx storage catalytic converter 10, heating element 11, Supply valve 12, intercooler 13, supply line 14, Venturi nozzle 15, housing 16, oxidation catalyst coating 17, oxidation catalyst 18, further main catalyst 19, filter device 20, safety device 21, blower 22 and pressure accumulator 23.

1a, 1b, 1c and 1d show schematic graphic representations of different variants of a first embodiment of a spark-ignition engine arrangement according to the invention.

In this embodiment, the Otto engine arrangement comprises an Otto engine 1 and an exhaust gas aftertreatment system 2. The exhaust gas aftertreatment system 2 includes a main catalytic converter 3, a gasoline engine particle filter 4 arranged downstream of the main catalytic converter 3 and a NOx storage catalytic converter 10 arranged downstream of the Otto engine particle filter 4. In this embodiment, the main catalytic converter is 3 designed as a 3-way catalytic converter and arranged directly after the turbine 8 of the turbocharger 5, in particular close to the engine.

Alternatively, the exhaust aftertreatment system 2 includes a main catalytic converter 3, at least one additional catalytic converter, an oxidation catalytic converter 18, a gasoline engine particle filter 4 and a NOx storage catalytic converter 10.

Furthermore, the Otto engine assembly of Figures 1 includes a turbocharger 5 and a throttle valve 6. The turbocharger 5 includes a compressor 7 and a turbine 8. According to FIG 4 and the NOx storage catalytic converter 10, a heating element 11 is provided. The heating element 11, which is fed by the vehicle electrical system, makes it possible to heat up catalytic converters, with this heating up being able to take place flexibly and quickly.

In the normal operating phase, which corresponds to regular operation of the Otto engine arrangement, fuel is supplied to the Otto engine 1 . In the normal operating phase, the fuel is converted with air to form an exhaust gas.

In the normal operating phase, the Otto engine 1 is operated and/or regulated in a lambda window around λ=1. This means that the Otto engine 1 is operated oscillating around a lambda value X of 1.0 and is operated and/or regulated in the range from λ=0.9 to 1.1, preferably from λ=0.95 to 1.05 . According to this specific embodiment, provision can be made for Otto engine 1 to be operated rich or lean and/or regulated in phases or permanently in its normal operating phase.

According to this embodiment, the NOx storage catalytic converter 10 is the last catalytic converter of the exhaust gas aftertreatment system 2 in the direction of exhaust flow.

[00124] The exhaust gas emitted by the Otto engine 1 is as it flows through the exhaust aftertreatment

treatment system 2 and the exhaust gas aftertreatment components arranged in the exhaust gas aftertreatment system 2 cools down. Consequently, the exhaust gas flows through the NOx storage catalytic converter 10 at a temperature that is lower than the temperature entering the exhaust gas aftertreatment system 2. This makes it possible to reduce and/or prevent thermal stresses and thermal aging in the NOx storage catalytic converter 10 and, for example, to extend the service life of the NOx storage catalyst 10 to increase.

[00125] This makes it possible to resolve the aforementioned conflict of objectives and to create a method and an Otto engine arrangement which enable low fuel consumption, low pollutant emissions and a high degree of reliability and longevity.

Since the NOx storage catalytic converter 10 is provided according to this embodiment as the last exhaust gas component in the exhaust gas aftertreatment system 2, any desulfurization of the NOx storage catalytic converter 10 that may occur has the least thermal influence on the other exhaust gas aftertreatment components. During the desulfurization, the NOx storage catalytic converter 10 can be heated in a targeted manner to its desulfurization temperature, in particular 700° C., and damage to other exhaust gas aftertreatment components can be prevented and/or reduced.

If, as shown in FIG. 1b, a heating element 11 is arranged in front of the NOx storage catalytic converter 10, the NOx storage catalytic converter 10 can be brought to its desulfurization temperature by the heating element 11. In contrast to conventional methods, no additional fuel or only a small amount of additional fuel is required for the desulfurization of the NOx storage catalytic converter 10 and the particle emissions are also essentially not increased.

According to FIGS. 1c and 1d, the Otto engine arrangement comprises a supply line 14. The supply line 14 is set up for supplying air upstream of the NOx storage catalytic converter 10. In these variants, the oxidation catalytic converter coating 17 is provided in the front area of the NOx storage catalytic converter 10 . In the variants of the first embodiment shown in FIGS. 1c and 1d, air enters the supply line 14 after the compressor 7 of the turbocharger 5 and before the intercooler 13 of the turbocharger 5 and exits the supply line 14 before the NOx storage catalytic converter 10.

By supplying oxygen, the NOx storage catalytic converter 10 can be operated in so-called storage mode. In this case, NO can be stored at least temporarily in the NOx storage catalytic converter 10 and, if appropriate, the stored NO can then be converted into water, carbon dioxide and nitrogen.

In contrast to conventional methods, it is not necessary to periodically operate the Otto engine 1 lean or rich since the NOx storage catalytic converter 10 is supplied with oxygen and in particular air via the supply line 14 . Even in contrast to the method described in the prior art, it may be possible to operate and/or regulate the Otto engine 1, in particular always, in a lambda window around \=1.

During the supply of the oxygen, in particular the air, through the supply line 14, the oxygen content of the exhaust gas flowing through the main catalytic converter 3 or of the exhaust gas located in the main catalytic converter 3 can be less than 5% by volume or essentially zero.

During the supply of the oxygen, in particular the air, through the supply line 14, the amount of oxygen in the exhaust gas flowing through the main catalytic converter 3 or the amount of oxygen in the exhaust gas located in the main catalytic converter 3 can be kept so low that the efficiency of the main catalytic converter 3 is unaffected.

According to FIGS. 1c and 1d, it is provided that air flows through the NOx storage catalytic converter 10, which comprises the oxidation catalytic converter coating 17, as the only exhaust gas aftertreatment component during the supply of air.

According to FIG. 1d, compared to the gasoline engine arrangement of FIG. 1c, the Otto engine arrangement additionally comprises an exhaust gas recirculation line 9, namely a high-pressure EGR line of a high-pressure EGR system.

2a and 2b show schematic representations of different variants of a second embodiment of a gasoline engine arrangement according to the invention. The features of the variants of the embodiment according to FIGS. 2a and 2b can preferably correspond to the features of the embodiments according to FIGS. 1a, 1b, 1c and 1d.

According to FIG. 2a, an oxidation catalytic converter coating 17 is provided in the front area of the gasoline engine particle filter 4 .

According to FIG. 2b, an oxidation catalytic converter 18 having an oxidation catalytic converter coating 17 is provided in front of the gasoline engine particle filter 4 .

The oxidation catalyst coating 17 is formed from at least one element of the platinum metals or platinoids.

In these variants, air can be introduced upstream of the oxidation catalytic converter 18 or the gasoline engine particle filter 4 comprising the oxidation catalytic converter coating 17 into the exhaust gas aftertreatment system 2 via a feed line 14 .

Furthermore, the oxidation catalytic converter coating 17 is set up to convert nitrogen monoxide NO with oxygen O» to form nitrogen dioxide NO». As a result, 17 NO» is generated in or on the oxidation catalyst coating as soon as this NO and O;» is supplied.

The generated nitrogen dioxide NO» makes it possible to at least partially oxidize the combustible components of the particles located in the gasoline engine particle filter 4, in particular the carbon C. Soot oxidation essentially takes place according to the following rule:

2N02+C >2N0+ CO,

In the case of regeneration with nitrogen dioxide NO », the so-called passive regeneration, the soot oxidation processes can be better controlled and/or regulated in comparison to active regeneration, as a result of which the advantages mentioned above are realized.

Furthermore, the variants of the second embodiment make it possible for the nitrogen dioxide NO2 not converted by the gasoline engine particle filter 4 to be stored at least temporarily in the NOx storage catalytic converter 10 and/or optionally converted to water, carbon dioxide and nitrogen.

This means that in these variants, the gasoline engine particle filter 4 is regenerated synergistically and the nitrogen oxides can be stored in the NOx storage catalytic converter 10 and, if necessary, converted.

3 shows a schematic representation of a third embodiment of a spark-ignition engine arrangement according to the invention. The features of the third embodiment can preferably correspond to the features of the embodiments according to FIGS. 1a, 1b, 1c, 1d, 2a and 2b.

According to the third embodiment, the gasoline engine particle filter 4 and the NOx storage catalytic converter 10 are provided on two different carrier bodies and are arranged in a housing 16, namely a steel housing.

[00147] This enables thermal decoupling of the two exhaust gas aftertreatment components on the one hand and a compact design on the other.

In the embodiments shown in FIGS. 1, 2 and 3, oxygen and in particular air can be introduced upstream of the gasoline engine particle filter 4, upstream of the NOx storage catalytic converter 10 and/or upstream of the oxidation catalytic converter 18 that may be provided. The supply line 14 supplying the oxygen may comprise a safety device 21 and a supply valve 12 . Furthermore, the supply line 14 can introduce air from the environment or from the intake tract of the Otto engine arrangement into the exhaust gas aftertreatment system 2.

gene and in particular include a pressure accumulator 23, a fan 22 and / or an air filter. Provision can also be made for parts of the exhaust gas aftertreatment system 2 to be in the form of Venturi nozzles 15, in particular where the feed line 14 opens into the exhaust gas aftertreatment system 2.

4a and 4b show schematic representations of different variants of a fourth embodiment of a gasoline engine arrangement according to the invention. The features of the variants of the embodiment according to FIGS. 4a and 4b can preferably correspond to the features of the embodiments according to FIGS. 1a, 1b, 1c, 1d, 2a, 2b and 3.

According to FIG. 4a, the ambient air is introduced into the exhaust gas aftertreatment system 2 via a feed line 14 opening out in front of the NOx storage catalytic converter 10.

The variant according to FIG. 4b has a further main catalytic converter 19 in addition to the variant according to FIG. 4a.

In these variants, the exhaust gas aftertreatment system 2 is designed as a Venturi nozzle 15 in the area where the feed line 14 opens into the exhaust gas aftertreatment system 2 . Furthermore, an oxidation catalytic converter coating 17 can be provided on the NOx storage catalytic converter 10, in particular in its front area.

Figure 5 shows a schematic diagram of a fifth embodiment of a spark ignition engine assembly according to the invention. The features of the embodiment according to FIG. 5 can preferably correspond to the features of the embodiments according to FIGS. 1a, 1b, 1c, 1d, 2a, 2b, 3, 4a and 4b.

According to this embodiment, the exhaust gas aftertreatment system 2 comprises a main catalytic converter 3, an oxidation catalytic converter 18, a gasoline engine particle filter 4 and a NOx storage catalytic converter 10.

Ambient air is introduced into the exhaust gas aftertreatment system 2 upstream of the oxidation catalytic converter 18 via a supply line 14 .

6a, 6b and 6c show schematic diagrams of variants of a sixth embodiment of a spark-ignition engine arrangement according to the invention. The features of the embodiment according to FIGS. 6a to 6c can preferably correspond to the features of the embodiments according to FIGS. 1a, 1b, 1c, 1d, 2a, 2b, 3, 4a, 4b and 5.

According to FIG. 6a, ambient air, which has been filtered by a filter device 20, is introduced into the exhaust gas aftertreatment system 2 upstream of the NOx storage catalytic converter 10. On the supply line 14, a supply valve 12 and a safety device 21 are provided.

According to FIG. 6b, a further main catalytic converter 19 is arranged between the main catalytic converter 3 and the gasoline engine particle filter 4 in addition to the variant in FIG. 6a. The ambient air filtered by the filter device 20 is introduced in front of the NOx storage catalytic converter 10 by means of a blower 22, which is designed as an electric compressor 7 in this embodiment.

According to FIG. 6c, the air is introduced into a pressure accumulator 23 in front of the compressor 7 of the turbocharger 5 via a blower 22 . The air can then be introduced into the exhaust aftertreatment system 2 upstream of the NOx storage catalytic converter 10 via the pressure accumulator 23 .

Furthermore, an oxidation catalytic converter coating 17 can be provided on the NOx storage catalytic converter 10, in particular in its front area.

With this exemplary configuration, the effects of the present invention can be obtained.

The invention is not limited to the illustrated embodiments, but includes any Otto engine arrangement and any method according to the following claims.

Claims (1)

patent claims 1. Gasoline engine arrangement, - wherein the Otto engine arrangement comprises a Otto engine (1) and an exhaust gas after-treatment system (2) with at least one main catalytic converter (3), a Otto engine particle filter (4) and a NOx storage catalytic converter (10), - wherein the main catalytic converter (3) is designed or acts as a 3-way catalytic converter, - and wherein the main catalytic converter (3) is followed by the gasoline engine particle filter (4), which optionally acts as a 4-way catalytic converter, - and that the NOx storage catalytic converter (10) is arranged downstream of the gasoline engine particle filter (4), - and that, if appropriate, a further catalytic converter, in particular an oxidation catalytic converter (18), is arranged in front of the NOx storage catalytic converter (10), characterized, that in the front area of the NOx storage catalytic converter (10), in particular catalytically coated, heating element (11) for heating the NOx storage catalytic converter (10) is seen, wherein the heating element (11) after the Otto particle filter (4) is arranged. 2. Otto engine arrangement according to claim 1, characterized in that the Otto engine (1) is constructed as a Otto engine (1) regulated in a lambda window by )=1 before the exhaust gas after-treatment system (2). 3. Otto engine arrangement according to claim 1 or 2, characterized in that - that between the main catalytic converter (3) and the Otto engine particle filter (4) an oxidation catalytic converter (18) is provided, - wherein the oxidation catalytic converter (18) is a platinum metal, preferably platinum, rhodium and/or or palladium. 4. Gasoline engine arrangement according to one of the preceding claims, characterized in that - That the Otto engine particle filter (4) comprises the NOx storage catalytic converter (10), the NOx storage catalytic converter (10) being arranged in the rear area of the Otto engine particle filter (4), - and/or that the gasoline engine particle filter (4) has a coating that acts as a NOx storage catalytic converter (10), - and/or that the coating acting as a NOx storage catalytic converter (10) is applied in the flow direction of the exhaust gas from the back of the gasoline engine particle filter (4), - wherein the coating acting as a NOx storage catalyst (10) comprises in particular a barium component, preferably barium oxide, barium carbonate and/or a cerium oxide component. 5. Otto engine arrangement according to one of the preceding claims, characterized in that - that a between the main catalytic converter (3) and the further catalytic converter, in particular the oxidation catalytic converter (18), between the main catalytic converter (3) and the gasoline engine particle filter (4) and/or between the gasoline engine particle filter (4) and the NOx storage catalytic converter (10) in the exhaust gas aftertreatment system (2) is provided which opens into the supply line (14), - And that the supply line (14) for supplying oxygen and in particular air into the exhaust gas aftertreatment system (2) is set up and in particular flows through it unidirectionally. 6. Gasoline engine arrangement according to one of the preceding claims, characterized in that - that the gasoline engine arrangement comprises a feed line (14) which opens into the exhaust gas aftertreatment system (2), - that the feed line (14) upstream of the spark-ignition engine particle filter (4), upstream of the NOx storage catalytic converter ( 10) and/or before any further catalytic 10 11. 12. Austrian AT 521 744 B1 2022-05-15 gate, in particular the oxidation catalytic converter (18), opens into the exhaust gas aftertreatment system (2), - wherein the feed line (14) branches off between a compressor (7) and an intercooler (13) of the turbocharger (5), - or wherein the supply line (14) branches off between an intercooler (13) of the turbocharger (5) and the Otto engine (1), - Or wherein the supply line (14) for the introduction of air from the environment outside the Otto engine arrangement to the ambient air, in particular unidirectionally, is open. Gasoline engine arrangement according to one of the preceding claims, characterized in net, - that a Venturi nozzle (15) is provided for introducing the ambient air of the supply line (14) into the exhaust gas aftertreatment system (2), - and that the Venturi nozzle (15) opens into the exhaust gas after-treatment system (2) in front of the gasoline engine particle filter (4). Gasoline engine arrangement according to one of the preceding claims, characterized in net, - that a controllable and/or adjustable blower (22) for conveying the oxygen, in particular for conveying the air, is provided on the supply line (14), - and/or that a supply valve (12) is provided along the supply line (14), the supply valve (12) being set up to regulate the quantity of oxygen or quantity of air which the gasoline engine particle filter (4), the NOx storage catalytic converter (10) and/or or the optionally provided further catalyst, in particular the oxidation catalyst (18). Otto engine arrangement according to one of the preceding claims, characterized in that the NOx storage catalytic converter (10) is the last catalytic converter of the exhaust gas aftertreatment system (2) in the flow direction of the exhaust gas. Gasoline engine arrangement according to one of the preceding claims, characterized in net, - that the petrol engine particle filter (4) is uncoated or designed as a 2-way catalytic converter or as a 3-way catalytic converter or as a 4-way catalytic converter, - or that the gasoline engine particulate filter (4) does not include a catalytic converter or a 2-way catalytic converter or a 3-way catalytic converter or a 4-way catalytic converter. Gasoline engine arrangement according to one of the preceding claims, characterized in net, - that after the Otto engine (1) and before the main catalytic converter (3), in particular in the front area of the main catalytic converter (3), a heating element (11), in particular catalytically coated, is provided for heating the main catalytic converter (3), - and/or that after the Otto engine (1), in particular after the oxidation catalytic converter (18), and before the Otto engine particle filter (4), particularly in the front area of the Otto engine particle filter (4), a heating element (11), in particular a catalytically coated one, for heating of the gasoline engine particle filter (4) is provided. Gasoline engine arrangement according to one of the preceding claims, characterized draws, - that the Otto engine (1) can be operated in an operating phase that includes a normal operating phase and an overrun phase, - that the petrol engine (1) converts fuel and air into an exhaust gas in the normal operating phase, - that the Otto engine (1) is preferably operated and/or regulated in a lambda window around A=1 in the normal operating phase, - that the overrun phase is formed by at least one unfired overrun phase and/or at least one fired overrun phase, 13. 14 15 16 17 Austrian AT 521 744 B1 2022-05-15 - that in the fired overrun phase the gas flowing through the main catalytic converter (3) is low in oxygen, in particular essentially free of oxygen, and in particular the exhaust gas of a stoichiometric or sub-stoichiometric, in particular phase-wise sub-stoichiometric, combustion is, - wherein an exhaust gas recirculation line (9) is provided, which supplies the Otto engine (1) in an unfired overrun phase with the exhaust gas generated before or during the transition from the normal operating phase to the unfired overrun phase in the Otto engine (1), - or wherein an exhaust gas recirculation line (9) is provided, which supplies the Otto engine (1) in an unfired overrun phase with the exhaust gas produced before or during the transition from the fired overrun phase to the unfired overrun phase in the Otto engine (1). Gasoline engine arrangement according to one of the preceding claims, characterized draws, - an oxidation catalytic converter (18) coated with an oxidation catalytic converter coating (17) is provided between the main catalytic converter (3) and the gasoline engine particle filter (4), - or that the petrol engine particle filter (4) is provided with an oxidation catalyst coating (17) at least in its front area, - The oxidation catalytic converter coating (17) being set up to convert NO with O» to NO». Gasoline engine arrangement according to one of the preceding claims, characterized draws, - that the Otto engine arrangement comprises a feed line (14) which opens into the exhaust gas aftertreatment system (2), - wherein oxygen and in particular air, preferably filtered ambient air, can be fed via the feed line (14) to the petrol engine particle filter (4), in particular for the regeneration of the petrol engine particle filter (4), and/or the oxidation catalytic converter (18), - and/or oxygen and in particular air, preferably filtered ambient air, can be fed via the feed line (14) to the NOx storage catalytic converter (10), in particular for storing and converting nitrogen oxides, and/or the oxidation catalytic converter (18). Gasoline engine arrangement according to one of the preceding claims, characterized draws, - that the exhaust aftertreatment system (2) includes an SCR catalytic converter, - that the SCR catalytic converter is arranged after the main catalytic converter (3), after the oxidation catalytic converter (18) and/or after the gasoline engine particle filter (4), - that the Otto engine arrangement comprises a supply line (14) which opens into the exhaust gas aftertreatment system (2) and can in particular be flown through unidirectionally, - And that via the supply line (14) the SCR catalytic converter, in particular for the reduction of nitrogen oxides, oxygen and in particular air, preferably filtered ambient air can be fed. Gasoline engine arrangement according to one of the preceding claims, characterized draws, - In front of the SCR catalytic converter and in particular after the oxidation catalytic converter (18), there is a metering device for introducing a fuel, in particular what is known as AdBlue®. Method for operating an Otto engine arrangement according to one of Claims 1 to 16, characterized, - That the Otto engine arrangement comprises a Otto engine (1) and an exhaust aftertreatment system (2) with a main catalytic converter (3), a Otto engine particle filter (4) and a NOx storage catalytic converter (10), - and that the exhaust gas first flows through the main catalytic converter (3), then the petrol engine particle filter (4) and finally the NOx storage catalytic converter (10). 5 sheets of drawings