KR20200104768A - System and method for exhaust gas after treatment, vehicle, and method for operating a vehicle - Google Patents

Abstract

Disclosed are a system and a method for post-treatment of exhaust gas, a vehicle, and a method of operating the vehicle. According to one embodiment of the present invention, the system for post-treatment of exhaust gas comprises: a catalyst converter which has a gas inlet, receives exhaust gas from an internal combustion engine through the gas inlet, and performs catalyst treatment for the exhaust gas; an exhaust gas line coupled to the gas inlet to couple the gas inlet to the exhaust of the internal combustion engine; a gas tank which stores gas fuel; an air tank which stores pressurized air; and a gas burner including an inlet which is coupled to the air tank and the gas tank, and an outlet which is coupled to the exhaust gas line on the upstream of the gas inlet of the catalyst converter, and burning the gas fuel introduced from the gas tank inside with the pressurized air introduced from the air tank so as to generate a high-temperature gas flow. According to the present invention, it is possible to heat the catalyst converter more efficiently.

Description

Exhaust gas aftertreatment system and method, and vehicle and vehicle operation method {SYSTEM AND METHOD FOR EXHAUST GAS AFTER TREATMENT, VEHICLE, AND METHOD FOR OPERATING A VEHICLE}

The present invention relates in particular to an exhaust gas aftertreatment system during operation of an internal combustion engine of a vehicle, for example a diesel engine. Further, the present invention relates to vehicles such as automobiles, buses and trucks. Further, the present invention relates to a method of operating a vehicle and a method of post-treating exhaust gas.

The catalytic converter is an exhaust gas control device that converts toxic gases and pollutants in exhaust gases from an internal combustion engine into low toxic or non-toxic substances by promoting redox reactions (reduction processes and complementary oxidation processes). Catalytic converters are used not only for kerosene heaters and stoves, but also for internal combustion engines fueled by gasoline or diesel, including in particular lean-burn engines. Another use of catalytic converters is known as gas engines, for example liquid natural gas engines or compressed natural gas engines.

SCR (Selective Catalytic Reduction) is a well-known technology used in catalytic converters, and nitrogen oxides, also known as NOx, are converted into diatomic nitrogen and water with the aid of a catalyst in a catalytic converter. A gaseous or fluid reducing agent such as anhydrous ammonia, liquid ammonia or urea is added to the stream of exhaust gas and adsorbed to the catalyst. Since the catalytic reaction is generally only initiated at temperatures above 200° C. to 250° C., the SCR converter requires a specific temperature to operate properly. Generally, the SCR is heated by passing exhaust gas. For this reason, it may take a relatively long time to heat the SCR converter under certain circumstances such as cold start or low load engine operation, for example during idling, or it is not possible without additional assistance until NOx emissions are effectively reduced. .

Efforts are being made to improve the performance of SCR and other catalytic converters in the heating step. For example, EP 2687694 A1 discloses providing an ozone generator configured to generate ozone that is injected into an exhaust pipe of an automobile upstream of an SCR converter. This approach converts the NO contained in NOx in the exhaust gas into NO ₂ with the aid of ozone. NO ₂ has a high reactivity and can be reduced to N ₂ in a chemical reaction with urea in SCR even when the exhaust gas temperature is low.

WO 2016/113045 A1 discloses another approach for improving the performance of the catalytic converter in the heating stage as pressurized air of the vehicle's air supply system is introduced into the exhaust gas line upstream of the catalytic converter. Accordingly, an exothermic reaction may occur in the catalytic converter under excessive air. Excess air promotes the reaction and thus accelerates the heating of the catalytic converter even when the exhaust gas temperature is relatively low.

It is an object of the present invention to provide an exhaust gas post-treatment system and method capable of heating a catalytic converter more efficiently, and a vehicle and a method of operating the vehicle.

The present invention relates to an exhaust gas post-treatment system according to claim 1, a vehicle according to claim 10, an operating method of a vehicle according to claim 12, and an exhaust gas post treatment method according to claim 14.

Further embodiments of the invention, with reference to the drawings, are subject to further subclaims and the following description.

A first aspect of the invention relates to an exhaust gas aftertreatment system. The system comprises a catalytic converter having a gas inlet, a catalytic converter receiving exhaust gas from an internal combustion engine at the gas inlet and receiving a catalytic treatment on the exhaust gas, the gas inlet to connect the gas inlet to the exhaust of the internal combustion engine. An exhaust gas line coupled to the gas inlet, a gas tank for storing gaseous fuel, and an air tank for storing pressurized air.

The exhaust gas line may include an inlet provided to be coupled to or connected to the exhaust of the internal combustion engine, and an outlet coupled or connected to the gas inlet of the catalytic converter. The exhaust gas line may be formed, for example, in a channel or pipe structure, and further configurations may be part or form part of this channel or pipe structure.

The gas tank can be configured to store gas or gaseous fuel in a liquid state, particularly under a predetermined pressure above atmospheric pressure. For example, the gas tank may be formed of metal. Similarly, the air tank may be configured to store pressurized air under a predetermined pressure above atmospheric pressure, for example in the range between 5 bar and 15 bar. For example, the air tank may be formed of metal.

The system further comprises a gas burner comprising an inlet coupled to the air tank and the gas tank, the gas burner comprising an outlet coupled to the exhaust gas line upstream of the gas inlet of the catalytic converter, the gas burner It may be configured to produce a hot gas flow by combusting gaseous fuel received from the gas tank therein with pressurized air received from the air tank. The outlet of the gas burner is coupled to the exhaust gas line at a location between the inlet and the outlet of the exhaust gas line and upstream of the catalytic converter with respect to the internal combustion engine. By supplying the hot gas flow generated by the gas burner to the exhaust gas line upstream of the catalytic converter, the catalytic converter can be heated by the hot gas flow.

According to a second aspect of the present invention, as an internal combustion engine and an exhaust gas post-treatment system according to the first aspect of the present invention, a high-temperature gas flow is reduced by combusting gaseous fuel received from the gas tank with pressurized air received from the air tank. An exhaust gas post-treatment system for generating and heating at least one of the exhaust gas from the catalytic converter and the internal combustion engine 101 by the high-temperature gas flow, and for post-treating the exhaust gas from the internal combustion engine, and compressed air There is provided a vehicle comprising a compressed air system comprising a reservoir of, wherein the reservoir forms an air tank of the exhaust gas aftertreatment system. Accordingly, the vehicle is a vehicle such as a vehicle, bus, or truck in which the reservoir of the pressurized air system of the vehicle is used as an air tank of the exhaust gas post-treatment system

A third aspect of the invention relates to a method of operating a vehicle according to the second aspect of the invention. The method comprises generating a hot gas flow by burning gaseous fuel with pressurized air in the gas burner, directing the hot gas flow to the exhaust gas line, and starting an internal combustion engine when a starting condition is met. Includes steps.

According to this aspect, the catalytic converter can be heated by the hot gas flow generated by the gas burner before starting the internal combustion engine. For example, this heating can be performed during the step in which the inlet air of the internal combustion engine is pretreated. This step can last, for example, about 2 to 15 seconds.

According to a fourth aspect of the present invention, generating a hot gas flow by burning gaseous fuel with pressurized air in a gas burner, exhausting from the internal combustion engine with the hot gas flow by inducing the hot gas flow with exhaust gas There is provided an exhaust gas post-treatment method comprising heating a gas and supplying the heated exhaust gas to a gas inlet of a catalytic converter to catalytically treat the heated exhaust gas.

The method according to this aspect of the invention can be carried out, for example, with the help of the system of the first aspect of the invention and/or in a vehicle according to the second aspect of the invention. Furthermore, the method according to this fourth aspect of the invention can be carried out as part of the method of the third aspect of the invention. For example, the method steps of this third aspect of the present invention can be carried out when the internal combustion engine is started after the temperature captured at the gas inlet of the catalytic converter reaches a predetermined temperature threshold. In this configuration, the method step of the fourth aspect can be carried out until the temperature captured at the gas inlet of the catalytic converter reaches a second predetermined temperature threshold, eg, the light off temperature of the catalytic converter.

One idea of the present invention is to provide a gas burner for the purpose of producing a hot gas stream used to heat the exhaust gas post-treatment component, in particular a catalytic converter, for example an SCR unit, located downstream of an internal combustion engine. It is a special offer.

As a result, the operating temperature of the catalytic converter and other configurations of the exhaust after treatment system (EATS) can be reached much faster than in conventional devices. In particular, the light-off temperature of the catalytic converter, that is, the temperature at which the catalytic reaction is started in the catalytic converter can be reached much earlier. Gas burners capable of combusting gaseous combustible materials provide the advantage that gaseous fuels such as natural gas are usually combusted with low particles and NOx emissions. In addition, gaseous fuel is generally available at an inexpensive price.

By providing a gas burner, it may be possible to heat the EATS before starting the engine. Indeed, the invention can be used to heat an aftertreatment system independent of engine operation. As a result, the invention provides an advantage with respect to the emission level, in particular during the cold start phase of the engine. Particularly in high-capacity engines with high thermal mass and EATS of high thermal mass, the emission and the heating time can be reduced. Thus, new and strict regulations can be met in the case of an internal combustion engine, especially a diesel engine. The present invention provides special advantages during cold climates and/or winters, as the heating energy is often available independently of electrical heating means that require a large amount of electrical energy.

In addition, since the present invention can use the pressurized air in the reservoir of the pressurized air system of the vehicle, the EATS can be implemented with a very compact design requiring only a minimum amount of configuration.

According to an embodiment of the EATS, the burner comprises a mixing unit configured to generate an air fuel mixture by mixing gas fuel received from the gas tank and pressurized air received from the air tank, and the air fuel mixture It includes an ignition device for igniting. That is, gas fuel stored in the gas tank and pressurized air stored in the air tank are mixed within the volume of the gas burner, and the gas burner includes an inclined blade for promoting turbulence in the gas flow entering the volume through the inlet. It can contain the same structure. The ignition device, for example an electric ignition device, is provided for igniting the air fuel mixture initially by introducing heat into the air fuel mixture, for example by creating a spark.

According to an embodiment, the ignition device may be formed by a spark plug or a piezo igniter. Spark plugs commonly used in internal combustion engines offer an inexpensive and reliable advantage. Piezo igniters are based on the principle of generating an electric arc due to sudden deformation of a piezo-electric material, thus providing the advantage of being able to operate independently of the electrical system. This deformation can be achieved by means of a spring-like mechanical configuration.

According to another embodiment, the system may further comprise a gas vaporizer configured to evaporate gaseous fuel stored in the gas tank. The gaseous fuel may be stored in a liquid state in the gas tank. The gas vaporizer may be arranged in a supply line connecting the gas tank with the inlet of the gas burner. For example, the gas vaporizer may comprise a heating element, for example an electric heating element, to heat the fuel passing through the supply line.

According to an embodiment, the system includes a reducing agent injector configured to inject or inject a reducing agent into an exhaust gas line upstream of the catalytic converter for catalytic reduction of exhaust gas in the catalytic converter, the reducing agent injector and the gas inlet of the catalytic converter It may further comprise a mixing unit arranged in the exhaust gas line between and configured to mix the reducing agent with the exhaust gas, and the outlet of the gas burner is coupled to the exhaust gas line upstream or downstream of the mixing unit. The reducing agent may be injected or injected in the form of gas and/or fluid.

Engaging the outlet of the gas burner upstream of the mixing unit has the advantage that the mixing unit is heated with the aid of a hot gas flow produced by the gas burner. Accordingly, liquid components that may be included in the reducing agent are evaporated, and the performance of the catalytic converter is further improved. Combining the outlet of the gas burner downstream of the mixing unit has the advantage that the reducing agent is already mixed with the exhaust gas and both are heated together by a hot gas stream from the gas burner. Further, since the hot gas stream is introduced immediately before the catalytic converter, the catalytic converter is heated within a short time.

According to an embodiment, the system may further include an oxidation catalyst configured to perform an oxidation treatment of exhaust gas and disposed in the exhaust gas line upstream of the catalytic converter, and the outlet of the gas burner is It can be coupled to the exhaust gas line either upstream or downstream. The oxidation catalyst may optionally include a particle filter.

Coupling the outlet of the gas burner upstream of the oxidation catalyst, for example between the inlet of the exhaust gas line and the oxidation catalyst, is an alternative option, such as a mixing unit located downstream of the oxidation catalyst and the oxidation catalyst. The configuration also offers the advantage of being heated. On the other hand, coupling the outlet of the gas burner downstream of the oxidation catalyst, for example between the oxidation catalyst and the selective mixing unit or between the selective mixing unit and the catalytic converter heats the catalytic converter to a predetermined temperature. The time required for this can be reduced.

According to one embodiment, the system may include a distribution manifold configured to selectively couple the outlet of the gas burner to a specific location in the exhaust gas line. For example, the distribution manifold may be configured to selectively couple the exhaust gas line between the catalytic converter and the mixing unit, between the mixing unit and the oxidation catalyst, or upstream of the oxidation catalyst. For example, in the method according to the third or fourth aspect of the present invention, first, the distribution manifold is positioned immediately adjacent to the gas inlet of the catalytic converter at the outlet of the gas burner for rapidly heating the catalytic converter. Can be combined with Then, the outlet of the gas burner may be coupled to the exhaust gas line between the mixing unit and the oxidation catalyst or upstream of the oxidation catalyst. Further, the location at which the outlet of the gas burner is coupled to the exhaust gas line may depend on the ambient temperature. For example, at a high ambient temperature, reaching a predetermined temperature within a predetermined time at the gas inlet of the catalytic converter may be sufficient to couple the outlet of the gas burner upstream of the oxidation catalyst to the exhaust gas line. On the other hand, at a low ambient temperature, it may be more preferable to couple the outlet of the gas burner to a position immediately adjacent to the gas inlet of the catalytic converter in order to quickly heat the catalytic converter within a predetermined time. Thus, the flexibility of the system can be improved with the aid of the manifold.

According to one embodiment, the system is a controller configured to control the operation of the gas burner according to at least one of a start command, a temperature at the gas inlet of the catalytic converter, and an oxygen content in the exhaust gas at the gas inlet of the catalytic converter It may include. The controller can be implemented as a processor, microcontroller, ASIC, FPGA, or similar processing device. The controller may be configured to generate a command signal to activate a control structure or apparatus of the gas burner to operate the gas burner. The control structure may be formed by an inlet valve connecting the gas tank and the air tank to the inlet of the gas burner and/or the ignition device or similar device.

The start command indicating that the ignition of the vehicle is on may be, for example, an electrical signal provided by the engine or other device of the vehicle. Optionally, the start command can be used to implement open loop control by triggering the operation of the gas burner for a predetermined time at a predetermined heat output. Optionally in addition to the start command, the temperature and the oxygen content at the gas inlet can be used to implement a closed loop control, and the controller meets a predetermined temperature and/or a predetermined oxygen content at the gas inlet. If possible, the operation of the gas burner is controlled to change the temperature and/or the oxygen content at the gas inlet.

The controller may also be configured to control the operation of the gas burner on initial ignition and/or heat output. For example, the ratio of pressurized air and gaseous fuel supplied from the air tank and the gas tank to the inlet of the gas burner may be determined by the temperature and/or oxygen content of the exhaust gas at the gas inlet of the catalytic converter, and/or other It can be varied depending on the operating conditions, in particular the thermodynamic state variables captured at the inlet of the catalytic converter or in the exhaust gas line.

According to one embodiment, the compressed air system is configured to supply compressed air to a brake system of a vehicle. For example, the reservoir can be coupled to the brake actuator of the brake system, for example a wheel cylinder, via a supply line and respective control devices such as valves and flaps. These structures are typically integrated into heavy duty vehicles (HDVs) such as trucks and buses or tractors. Thus, the EATS can be very easily integrated into a vehicle.

According to one embodiment, the vehicle includes a controller configured to control the air-fuel ratio of the internal combustion engine. Preferably, this controller incorporates the functions of the controller of EATS as described above. Thereby, the integration of EATS into the vehicle is further improved.

According to one embodiment of the method of the third aspect of the present invention, the starting condition is defined by the elapse of a predetermined time or a predetermined critical temperature. That is, after the catalytic converter is heated by the gas burner for a predetermined time, for example, for a time of 2 to 10 seconds, or the temperature at the gas inlet of the catalytic converter reaches a predetermined temperature threshold. It starts afterwards. In particular, the gas burner can be operated in open or closed loop control to create a starting condition at the gas inlet.

In closed loop control, the method comprises the steps of capturing the temperature at the gas inlet of the catalytic converter, for example by a temperature sensor, and starting the internal combustion engine when the captured temperature is equal to or greater than the predetermined critical temperature. It may include a step of.

Also optionally, the temperature can be captured at the gas inlet of the catalytic converter regardless of the open or closed loop control operation of the gas burner. In particular, the method comprises the steps of capturing a temperature at a gas inlet of the catalytic converter, and generating a hot gas stream by burning a gaseous fuel with pressurized air in the gas burner when the captured temperature is lower than the predetermined threshold temperature. It may include the step of. That is, if it is determined that the starting condition has already been satisfied before starting the vehicle, for example because the starting of the vehicle was turned off only a short time before, then heating is not required, and thus the gas burner is not operated.

According to an embodiment of the method according to the third or fourth aspect, for catalytic reduction in the catalytic converter, a reducing agent is injected or injected into the exhaust gas by a reducing agent injector, and the reducing agent is at the high temperature of the gas burner. It is injected or injected either upstream or downstream of the gas stream. The reducing agent can be for example urea.

According to another embodiment, pressurized air may be supplied to the gas burner at a pressure of 5 bar to 15 bar. The gaseous fuel may be supplied to the gas burner at the same pressure as described above. By using a pressure higher than atmospheric pressure, the hot gas stream produced by the gas burner can be introduced at a relatively high pressure into the exhaust gas line. Accordingly, the flow rate in the exhaust gas line is increased, which advantageously increases heat transfer and accelerates the heating of the catalytic converter.

The features described herein for the above EATS and vehicles are also disclosures to the method of the third and fourth aspects of the invention, and vice versa.

As used herein, “gas fuel” is a combustible material that takes on a gaseous state under atmospheric conditions. Atmospheric conditions are given at standard temperature and pressure (STP), ie 0° C. and 1013.25 hPA. The gaseous fuel is, for example, methane, propane, butane, mixtures thereof or natural gas, or may include them.

According to an embodiment of the present invention, the temperature of the catalytic converter and other components of the exhaust gas post-treatment system can reach its operating temperature very quickly, and in particular, the temperature of the catalytic converter is the temperature at which the catalytic reaction starts in the catalytic converter. Can be reached.

Further, according to an embodiment of the present invention, by being used to heat an exhaust gas aftertreatment system independent of engine operation, the present invention can provide an emission level advantage during the cold start phase of the engine.

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated herein to form a part of this specification. The drawings show one embodiment of the present invention and together with the description of the invention serve to explain the principles of the present invention. Other embodiments of the invention and many of the intended advantages of the invention may be better understood by reference to the following detailed description. Components in the drawings do not necessarily need to be scaled in proportion to each other. In the drawings, unless otherwise indicated, the same reference numerals denote identical or functionally similar elements.
1 schematically shows a vehicle including an exhaust gas aftertreatment system according to an embodiment of the present invention.
Fig. 2 schematically shows a gas burner used in an open gas aftertreatment system according to an embodiment of the present invention.
3 schematically shows an exhaust gas aftertreatment system according to a further embodiment of the invention.
4 schematically shows an exhaust gas aftertreatment system according to another further embodiment of the invention.
5 schematically shows an exhaust gas aftertreatment system according to another further embodiment of the present invention.
While specific embodiments have been shown and described herein, it will be apparent to those skilled in the art that various substitutions and/or equivalent implementations may be substituted for the specific embodiments without departing from the scope of the present invention. In general, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

1 schematically shows a vehicle 100 including an internal combustion engine 101 such as a diesel engine and an exhaust gas aftertreatment system 10 (EATS). As shown in Fig. 1, the vehicle 100 includes a compressed or pressurized air system 102 including a reservoir 104 that stores pressurized air.

The engine 101 drives a drive shaft 105 that sequentially drives at least one shaft 106 and 107 of the vehicle 100. In order to change the rotational motion of the shafts 106 and 107 into the translational motion of the vehicle 100, the wheel W is coupled to the shafts 106 and 107 as symbolically shown in FIG. 1.

The reservoir 104 may be implemented as a tank configured to store air under a pressure of, for example, 5 bar to 15 bar. The pressurized air system 102 includes a pneumatic line 108 connected to the reservoir to direct air from the reservoir 104 to various locations within the vehicle 100.

Further, the vehicle 100 includes a brake system symbolically shown as block 103 in FIG. 1. The brake system 103 is configured to apply a friction force to the wheel W to brake the vehicle 100. For example, the brake system 103 may include a pneumatic actuator (not shown). Thus, the brake system 103 can be coupled to the compressed air system 102 by means of a pneumatic line 108 as schematically shown in FIG. 1. In general, the compressed air system 102 is configured to supply compressed air to the brake system 103 of the vehicle 100.

The engine 101 exemplarily shown in FIG. 1 includes an air inlet 15a and an air inlet 15a to inject or inject fresh and cooled air into the engine 101 through a turbocharger 17 and a charge air cooler 16. Are combined. The engine 101 discharges exhaust gas through a gas pipe 15, and the exhaust gas is discharged from the exhaust gas 15b of the vehicle after passing through the turbine of the turbocharger.

The system 10 is configured to purify exhaust gases emitted from the internal combustion engine 101 of the vehicle 100. As exemplarily shown in FIG. 1, the system 10 comprises a selective oxidation catalyst or optionally a diesel particulate filter (both of which are indicated by reference numeral 19 in FIG. 1), a selective reducing agent injector 11, an optional mixing unit ( 12) and a series of exhaust gas aftertreatment devices comprising a catalytic converter 2, which may be, for example, a SCR (Selective Catalytic Reduction) device. In addition, the system 10 comprises a gas burner 1, a gas tank 3, and an air tank 4 which may be formed by the reservoir 104 of the pressurized air system 102.

1, the gas inlet 2a of the catalytic converter 2 may be coupled to the exhaust 15b of the engine 101 through the exhaust gas line 20. In particular, the inlet 21 of the exhaust gas line 20 is coupled to the exhaust 15b of the engine 101, and the outlet 22 of the exhaust gas line 20 is the gas inlet 2a of the catalytic converter 2 Is bound to That is, the exhaust gas generated by the engine 101 is introduced into the exhaust gas line 20 through the inlet 21, flows through the exhaust gas line 20 to the outlet 22 of the exhaust gas line 20, and , Supplied to the gas inlet 2a of the catalytic converter 2. Thus, the flow direction is defined from the inlet 21 of the exhaust gas line 20 to the inlet 2a of the catalytic converter 2.

As shown in FIG. 1, the selective oxidation catalyst 19 can be arranged in the exhaust gas line 20 adjacent to the inlet 21, ie upstream of the catalytic converter 2. The oxidation catalyst 19 may be of a general design and is configured to perform an oxidation treatment of exhaust gas, for example, in order to convert unburned hydrocarbons into carbon dioxide and water.

The selective reducing agent injector 11 is connected to the exhaust gas line 20 upstream of the catalytic converter 2, preferably between the catalytic converter 2 and the oxidation catalyst 19, as exemplarily shown in FIG. 1. Are combined. The injector 11 is configured to inject or inject a reducing agent into the exhaust gas line 20 upstream of the catalytic converter 2 for catalytic reduction of the exhaust gas in the catalytic converter 2. The reducing agent acts as a reducing agent in the catalytic process inside the SCR catalytic converter 2 in a conventional manner. For example, the SCR catalytic converter 2 may comprise a catalytically active substrate arranged between an inlet surface and an outlet surface (not shown). For example, the substrate may comprise a ceramic monolith having a honeycomb structure, for example providing a plurality of catalytically active sub-channels in a conventional manner, and the exhaust gas is used for catalytic treatment. It is guided through sub-channels.

Optionally, a mixing unit 12 is provided for enhancing mixing between the reducing agent, for example urea and the exhaust gas flowing in the exhaust gas line 20. Accordingly, the mixing unit 12 may be arranged downstream of the position where the reducing agent injector 11 is coupled to the exhaust gas line 20 as exemplarily shown in FIG. 1.

The gas tank 3 is a tank or container capable of or configured to store fuel in a liquid or gaseous state, in particular under pressures above atmospheric pressure, for example from 5 bar to 15 bar. For example, the gas tank 3 can be a metal tank of any desired shape. Fuel combustible materials such as natural gas, which are in gaseous state under atmospheric pressure and temperature, can be used. The gas tank may for example store liquefied petroleum gas or compressed natural gas.

The gas burner 1 is shown in more detail in FIG. 2. The gas burner 1 comprises an inlet 1a coupled to a gas tank 3 and an outlet 1b coupled to an exhaust gas line 20. Further, the gas burner 1 comprises a combustion chamber 7. Optionally, the gas burner 1 comprises a mixing section 5 and an ignition device 6.

The inlet 1a may include a flow control device such as a first valve 23 and a second valve 24 as exemplarily shown in FIG. 2. The control device is configured to change the flow rate of the fluid. In particular, the first valve 23 couples the gas tank 3 to the gas burner 1, and the second valve 23 couples the air tank 4 or the reservoir 104 to the gas burner 1 . The gaseous fuel stored in the gas tank 3 and the pressurized air stored in the air tank 4 are burned together with the pressurized air to create a hot gas flow provided at the outlet 1b of the gas burner 1 Can be introduced into the combustion chamber 7 to be used.

As schematically shown in Fig. 2, the mixing section 5 may be arranged adjacent to the inlet 1a, and the gas fuel received from the gas tank 3 and the pressure received from the air tank 4 By mixing air, an air fuel mixture is produced. For example, a plurality of blades (not shown) may be disposed on the mixing unit 5.

The ignition device 6 serves to initially ignite the air fuel mixture in the combustion chamber 7. For example, the ignition device 6 can be formed by a spark plug or a piezo igniter.

As illustratively shown in FIG. 1, the gas tank 3 and the air tank 4 are connected to the inlet 1a of the gas burner, for example via a supply line. Optionally, a gas vaporizer 8 configured to evaporate the gaseous fuel stored in the gas tank 3 can be arranged in the supply line between the gas tank 3 and the inlet 1a of the gas burner. For example, the gas vaporizer 8 may be implemented as an electric heater.

Referring again to FIG. 2, the gaseous pressurized air and gaseous fuel, which are selectively premixed in the mixing unit 5, are introduced into the gas burner 1 through the inlet 1a, and the gaseous fuel is the combustion chamber 7 ) Is burned with air. Thereby, the hot gas flow flows out of the combustion chamber 7 at the outlet 1b of the gas burner 1.

The outlet 1b of the gas burner is coupled to the exhaust gas line 20. 1, the outlet 1b of the gas burner is directly adjacent to the inlet 2a of the catalytic converter 2, for example of the selective mixing unit 12 and the catalytic converter 2 It can be coupled to the exhaust gas line 20 between the gas inlets 2a. In general, the outlet 1b of the gas burner is coupled to the exhaust gas line 20 downstream of the gas inlet 2a of the catalytic converter 2. Thereby, the high-temperature gas can be introduced into the exhaust gas line 20 downstream of the catalytic converter 2 and can be supplied to the catalytic converter 2. Thus, the catalytic converter 2 can be heated even when the temperature of the exhaust gas is low, or the engine 101 is stopped, for example, and there is no flow of the exhaust gas from the engine 101.

Alternatively, the outlet 1b of the gas burner can be coupled to the exhaust gas line 20 upstream of the mixing unit 12, as exemplarily shown in FIGS. 3 and 4. Optionally, the outlet 1b of the burner is an exhaust gas between the mixing unit 12 and the oxidation catalyst 19, i.e. downstream of the oxidation catalyst 19 and upstream of the mixing unit 12 as shown in FIG. It can be coupled to line 20. 4 shows that the outlet 1b of the gas burner 1 is upstream of the oxidation catalyst 19, i.e. between the oxidation catalyst 19 and the inlet 21 of the exhaust gas line 20, to the exhaust gas line 20. It shows an example of being combined. In general, the outlet 1b of the gas burner 1 can be coupled to the exhaust gas line 20 upstream of the gas inlet 2a of the catalytic converter 2.

The system 10 shown in FIG. 5 differs from the system 10 shown in FIG. 1 in that it includes a distribution manifold 9. The distribution manifold 9 is coupled to the outlet 1b of the gas burner 1 and includes a plurality of distribution outlets 9b, 9c, 9d. The first distribution outlet 9b is coupled to the exhaust gas line 20 between the catalytic converter 2 and the mixing unit 12. The second distribution outlet 9c is connected to the exhaust gas line 20 between the mixing unit 12 and the oxidation catalyst 10. The third distribution outlet 9d is coupled to the exhaust gas line 20 upstream of the oxidation catalyst 19. The distribution manifold 9 has a flap system (not shown) configured to selectively guide fluid between the outlet 1b of the gas butter 1 and one of the distribution outlets 9b, 9c, 9d. Can include. Thus, the distribution manifold 9 is selectively gas burner 1 between the catalytic converter 2 and the mixing unit 12, between the mixing unit 12 and the oxidation catalyst 19, or upstream of the oxidation catalyst 19. ) Is configured to couple the outlet 1b to the exhaust gas line 20.

As shown in FIGS. 1, 3 and 4, a controller 13 may be provided in the system 10 and/or the vehicle 100. The controller 13 may comprise a data storage device, in particular a nonvolatile data storage device such as a hard disk drive or a flash drive, and a processing unit such as a CPU. Of course, the controller 13 may be implemented as a microcontroller, ASIC, RPGA, or the like. The controller 13 is functionally connected to the gas burner 1 and optionally the engine 101 of the vehicle 100, for example via a wireless or wired connection. The controller 13 is configured to generate control commands for operating the various control devices of the system 10 and/or engine 101. In addition, the controller 13 can be functionally connected to various sensors provided through the system 10, for example a temperature sensor and/or a lambda sensor provided at the gas inlet 2a of the catalytic converter 2.

The controller 13 is at the gas inlet 2a of the catalytic converter 2, the temperature captured by the temperature sensor (not shown), for example, and the catalytic converter 2 captured by the lambda sensor, for example It is configured to control the operation of the gas burner 1 according to at least one of the oxygen content in the exhaust gas at the gas inlet 2a of. Additionally or alternatively, the controller 13 can be configured to control the operation of the gas burner 1 depending on the starting conditions. The starting condition is, for example, when the controller 13 detects a start signal indicating that the ignition of the vehicle 100 is turned on, for example an electrical signal provided by the engine 101 or another device of the vehicle 100 Can be satisfied.

In particular, the controller 13 is configured to control the operation of the gas burner 1 for initial ignition of gaseous fuel. That is, the controller 13 can generate a command signal that causes the ignition device 6 to generate a spark to initiate combustion of the gas fuel in the gas burner 1. Additionally or alternatively, the controller 13 can be configured to control the operation of the gas burner 1 on heat output. For example, the controller 13 may generate a command signal that causes the control device, for example valves 23, 24, to change the flow rate of gaseous fuel and/or pressurized air. Thereby, the air-fuel ratio can also be changed.

The controller 13 may be configured to control the optional distribution manifold 9. That is, the controller 13 connects the outlet 1b of the gas burner 1 to one of the manifold outlets 9b, 9c, 9d by the flap system (not shown) of the distribution manifold 9 You can generate a command signal to make it happen.

Further, the controller 13 may be configured to control the operation of the internal combustion engine 101 of the vehicle 100, for example the air-fuel ratio in the internal combustion engine 101.

The vehicle 100 operating method and the exhaust gas post-treatment method will be described below by way of example with reference to the vehicle 100 and system 10 described above. In particular, the controller 13 may be configured to cause the configuration of the system 10 and vehicle 100, in particular the gas burner 1 and engine 101, to be operated according to the method steps described below.

The method of operating the vehicle 100 may optionally include the step of capturing the temperature at the gas inlet 2a of the catalytic converter 2, for example by a temperature sensor (not shown). The hot gas flow is created by combusting gaseous fuel from the gas tank 3 in the gas burner 1 with pressurized air from the air tank 4 or the reservoir 104. Optionally, the hot gas stream can be created only when the captured temperature is below a certain critical temperature, or generally when the starting conditions are not met. In order to generate the hot gas flow, the controller 13 can control the valves 23 and 24 and the ignition device 6. The hot gas stream is directed to the exhaust gas line 20, in particular to one of the locations of the exhaust gas line 20 as shown in FIGS. 1, 3 or 4. When the captured temperature is equal to or higher than the predetermined threshold temperature, or when other starting conditions are satisfied, the internal combustion engine 101 is started. For example, the controller 13 initiates combustion of the air fuel mixture of the engine 101.

The exhaust gas post-treatment method is when the temperature at the inlet 2a of the catalytic converter 2 is still below a threshold value, that is, the light-off temperature of the catalytic converter 2, for example, after a cold start of the engine 101, the engine ( 101) is in operation.

According to this method, a hot gas flow is produced by combusting gaseous fuel with pressurized air in the gas burner 1 as described above. The hot gas stream is supplied to the exhaust gas line 20 to heat the exhaust gas from the internal combustion engine 101 into the hot gas stream, so that the hot gas stream is introduced into the exhaust gas. The heated exhaust gas is directed to a gas inlet 2a of the catalytic converter 2 through an exhaust gas line 20 to perform a catalytic treatment on the heated exhaust gas. Optionally, the reducing agent may be injected or injected into the exhaust gas by the reducing agent injector 11 for catalytic reduction in the catalytic converter 2 by the injector 11. As described above, the reducing agent may be injected or injected in the downstream or upstream of the hot gas flow of the gas burner 1.

Although the above-described systems and methods have been described in connection with vehicles such as trucks or automobiles, it may be clearly and unambiguously understood by those skilled in the art that the systems and methods described herein can be applied to various objects including combustion engines. have.

The invention has been described in detail according to an exemplary embodiment. However, it will be apparent to those skilled in the art that modifications can be made to these embodiments without departing from the principles and central spirit of the present invention, the scope of the present invention defined in the claims, and their equivalents.

1: gas burner
1a: inlet of gas burner
1b: outlet of gas burner
2: catalytic converter
2a: gas inlet of the catalytic converter
2b: gas outlet of the catalytic converter
3: gas tank
4: air tank
5: gas burner mixing section
6: ignition device
7: combustion chamber
8: gas vaporizer
9: distribution manifold
9c-d: distribution outlet
10: exhaust gas aftertreatment system
11: reducing agent injector
12: mixing unit
13: controller
15: gas pipe
15a: air inlet
15b: exhaust
16: charge air cooler
17: turbocharger
19: oxidation catalyst / particulate filter
20: exhaust gas line
21: inlet of exhaust gas line
22: outlet of the exhaust gas line
23: first valve
24: second valve
100: vehicle
101: internal combustion engine
102: pressurized air system
103: brake system
104: reservoir
105: drive shaft
106, 107: axis
108: pneumatic line
W: wheel

Claims (16)

A catalytic converter (2) having a gas inlet (2a), configured to receive exhaust gas from the internal combustion engine (101) at the gas inlet (2a), and to perform a catalytic treatment on the exhaust gas;
An exhaust gas line (20) coupled to the gas inlet (2a) to couple the gas inlet (2a) to the exhaust (15b) of the internal combustion engine (101);
A gas tank 3 for storing gaseous fuel;
An air tank 4 for storing pressurized air; And
An inlet (1a) coupled with the air tank 4 and the gas tank 3, and an outlet coupled to the exhaust gas line 20 upstream of the gas inlet 2a of the catalytic converter 2 ( A gas burner (1) comprising 1b) and configured to produce a hot gas flow by combusting gaseous fuel received from the gas tank (3) therein with pressurized air received from the air tank (4). ;
Exhaust gas aftertreatment system 10 comprising a. The method of claim 1,
The gas burner (1)
A mixing section (5) configured to produce an air fuel mixture by mixing gas fuel received from the gas tank (3) and pressurized air received from the air tank (4); And
An ignition device (6) for igniting the air fuel mixture;
Exhaust gas aftertreatment system 10 comprising a. The method of claim 2,
The ignition device 6 is an exhaust gas aftertreatment system 10 formed by a spark plug or a piezo igniter. The method of claim 1,
Exhaust gas aftertreatment system (10) further comprising a gas vaporizer (8) configured to evaporate gaseous fuel stored in the gas tank (3). The method of claim 1,
A reducing agent injector 11 configured to inject or inject a reducing agent into the exhaust gas line 20 upstream of the catalytic converter 2 for catalytic reduction of the exhaust gas in the catalytic converter 2; And
A mixing unit 12 arranged in the exhaust gas line 20 between the reducing agent injector 11 and the gas inlet 2a of the catalytic converter 2 and configured to mix the exhaust gas and the reducing agent;
Including,
The outlet (1b) of the gas burner (1) is coupled to the exhaust gas line (20) upstream or downstream of the mixing unit (12). The method of claim 1,
Further comprising an oxidation catalyst 19 disposed in the exhaust gas line 20 upstream of the catalytic converter 2 and performing oxidation treatment of the exhaust gas,
An exhaust gas aftertreatment system (10), wherein the outlet (1b) of the gas burner (1) is coupled to the exhaust gas line (20) upstream or downstream of the oxidation catalyst (19). The method of claim 1,
A reducing agent injector 11 configured to inject or inject a reducing agent into the exhaust gas line 20 upstream of the catalytic converter 2 for catalytic reduction of the exhaust gas inside the catalytic converter 2;
A mixing unit 12 disposed in the exhaust gas line 20 between the reducing agent injector 11 and the gas inlet 2a of the catalytic converter 2 and configured to mix the reducing agent with the exhaust gas;
An oxidation catalyst 19 disposed in the exhaust gas line 20 upstream of the reducing agent injector 11 and performing an oxidation treatment of the exhaust gas; And
Between the catalytic converter (2) and the mixing unit (12), between the mixing unit (12) and the oxidation catalyst (19), or upstream of the oxidation catalyst (19) of the gas burner (1). A distribution manifold (9) configured to selectively couple an outlet (1b) to the exhaust gas line (20);
Exhaust gas aftertreatment system comprising a (10) The method of claim 7,
According to at least one of a start command, a temperature at the gas inlet 2a of the catalytic converter 2, and the oxygen content in the exhaust gas at the gas inlet 2a of the catalytic converter 2, the gas burner ( The exhaust gas aftertreatment system 10 further comprising a controller 13 configured to control the operation of 1). The method of claim 8,
The controller 13 is
An exhaust gas aftertreatment system (10) configured to control operation of the gas burner (1) for at least one of initial ignition and heat output. Internal combustion engine 101;
The gas fuel received from the gas tank 3 is burned with pressurized air received from the air tank 4 to generate a high temperature gas flow, and the catalytic converter 2 and the internal combustion engine 101 An exhaust gas post-treatment system (10) for heating at least one of the exhaust gases from) and post-treating the exhaust gas from the internal combustion engine; And
A compressed air system 102 including a reservoir 104 of compressed air;
Including,
The storage tank 104 is a vehicle 100 that forms the air tank 4 of the exhaust gas post-treatment system 10 The method of claim 10,
The compressed air system 102 is configured to supply compressed air to the brake system 103 of the vehicle 100. Creating a hot gas stream in the gas burner 1 by burning the gaseous fuel with pressurized air;
Directing the hot gas flow into an exhaust gas line (20); And
Starting the internal combustion engine when the starting condition is satisfied;
Operating method of the vehicle 100 comprising a. The method of claim 12,
The above starting condition is
The method of operation of the vehicle 100 defined by the lapse of a predetermined time or a predetermined critical temperature. Creating a hot gas stream in the gas burner 1 by burning the gaseous fuel with pressurized air;
Heating the exhaust gas from the internal combustion engine 101 with the hot gas stream by directing the hot gas stream to the exhaust gas; And
Supplying the heated exhaust gas to a gas inlet 2a of a catalytic converter 2 to catalytically treat the heated exhaust gas;
Exhaust gas post-treatment method comprising a. The method of claim 14,
Further comprising the step of injecting or injecting a reducing agent into the exhaust gas by a reducing agent injector 11 for catalytic reduction in the catalytic converter 2,
The exhaust gas post-treatment method in which the reducing agent is injected or injected upstream or downstream of the hot gas flow of the gas burner (1). The method of claim 14,
The exhaust gas post-treatment method wherein the pressurized air is supplied to the gas burner 1 at a pressure of 5 to 15 bar.

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