L-shaped mixing and evaporating device

Abstract

The invention relates to an evaporation and gas mixing device for an exhaust gas aftertreatment system for mixing an exhaust gas stream from an exhaust gas aftertreatment system with an evaporated reducing agent.

Description

Technical Field

[0001] The present invention relates to a liquid vaporization and gas mixing device for an exhaust gas aftertreatment system, the device being used to mix an exhaust gas flow from an internal combustion engine with a vaporized reducing agent. Furthermore, the present invention relates to an aftertreatment system for exhaust gases from an internal combustion engine incorporating the device. Furthermore, the present invention relates to a vehicle comprising the device according to the present invention and the aftertreatment system. The present invention further relates to the use of the device according to the present invention for mixing an exhaust gas flow from an internal combustion engine with a vaporized liquid reducing agent. Background Art

[0002] Achieving efficient evaporation of an aqueous urea solution from a dosing module, uniform mixing of the resulting reducing agent product (e.g., ammonia) into the exhaust gas, and subsequent uniform distribution across the catalytic components is a known challenge in the field of exhaust aftertreatment systems. Several inventions have been proposed to achieve this while minimizing the risk of urea deposits, minimizing backpressure, and minimizing space requirements. An exhaust aftertreatment system including a selective catalytic reduction (SCR) system may be included downstream of an internal combustion engine to remove or reduce nitrogen oxide (NOx) emissions from the engine. The SCR system involves introducing a reducing agent into the exhaust gas stream. A mixer is added to aid in evaporating, decomposing, and mixing the reducing agent in the exhaust gas stream. Adequate mixing can help improve performance by ensuring uniform distribution of the reducing agent, which enables the catalytic reaction to proceed uniformly across the cross-section of the catalyst, thereby minimizing ammonia slip and NOx emissions. US2010139258 relates to exhaust mixing systems, and more particularly to mixing systems for SCR systems. International patent application PCT / EP2019 / 061541 relates to a different mixing device, which concerns a device for evaporating a liquid spray and subsequently mixing it into the exhaust gas from an internal combustion engine, the internal combustion engine comprising a housing including a flow-guiding device located inside the housing. Summary of the Invention

[0003] The present invention solves many of the problems of prior art mixing systems for aftertreatment systems while also differing from them. The result is a compact mixing system that meets functional requirements, yet is simple to manufacture, allows for axial dosing from the top, and is scalable to various catalyst diameters. The present invention relates to a novel, compact, L-shaped evaporation and gas mixing device intended to form part of a vehicle exhaust aftertreatment system. Efficient evaporation of urea-water droplets from a dosing module, uniform mixing of these evaporated urea components and subsequent reducing agent products, such as ammonia, into the exhaust gas, and subsequent uniform distribution over the catalytic components is a known problem in the field, which the present invention now addresses. Numerous inventions have been proposed to achieve this while minimizing the risk of urea deposits, backpressure, and space requirements. Intended for use in an aftertreatment system, harmful exhaust gases from a vehicle engine pass through an oxidation catalyst, such as a diesel oxidation catalyst (DOC), and / or a particulate filter, such as a diesel particulate filter (DPF), before entering the compact exhaust gas mixing device of the present invention.

[0004] The proposed invention achieves all of the above objectives while being different from existing inventions. The result is a compact mixing system that meets functional requirements, can be used with multiple different dosing modules, and can be scaled for different catalyst diameters.

[0005] The mixing device of the present invention allows for the evaporation of a liquid reductant, such as an aqueous urea solution, and subsequent mixing of the evaporated reductant with exhaust gas, while minimizing the space requirements in the direction of exhaust gas flow through an exhaust aftertreatment system incorporating the device of the present invention. This device allows an exhaust aftertreatment system incorporating the device of the present invention to disperse an improved mixture of exhaust gas and reductant over the surface of a selective catalytic reduction (SCR) to reduce NOx to harmless nitrogen and water. In this regard, the aqueous urea solution is injected under pressure into the mixing system through a reductant dosing module, forming a liquid spray that is exposed to the fast-moving exhaust gas flow within the device, thereby enhancing evaporation.

[0006] In a first aspect, the present invention relates to an evaporation and gas mixing device for an exhaust gas aftertreatment system, the device for mixing an exhaust gas flow from the exhaust gas aftertreatment system with an evaporated reducing agent, the device comprising:

[0007] a) a housing having an upstream inlet for receiving a flow of exhaust gas and a downstream outlet for distributing the flow of exhaust gas after mixing with a vaporized reducing agent,

[0008] b) a mixing chamber located within the housing for swirling the exhaust gas flow and the evaporated reductant for mixing within the chamber, the mixing chamber having at least one opening for introducing the reductant into the mixing chamber, and having at least two separate inlets for receiving the exhaust gas flow and at least one outlet communicating with a downstream outlet of the housing for distributing the exhaust gas flow after mixing with the evaporated reductant,

[0009] c) a dosing module for introducing a reducing agent into the mixing chamber through the at least one opening for evaporation and mixing with the exhaust gas flow, wherein the dosing module is arranged at an end of the mixing chamber opposite the at least one outlet of the mixing chamber,

[0010] d) a first guiding device, located within the housing, having at least one inlet adapted to receive the exhaust flow and guide it to the mixing chamber, wherein the exhaust flow is guided perpendicularly to the exhaust flow distributed from the at least one outlet of the mixing chamber,

[0011] e) a second guide device located within the housing and arranged at one end of the mixing chamber, opposite the at least one outlet of the mixing chamber, the second guide device having at least one inlet adapted to receive the exhaust gas flow and guide it into the mixing chamber, wherein the exhaust gas flow is guided perpendicularly to the exhaust gas flow distributed from the at least one outlet of the mixing chamber, and wherein the second guide device has an opening for introducing the reducing agent into the mixing chamber.

[0012] In one embodiment, the mixing chamber is adapted to swirl the exhaust flow clockwise and / or counterclockwise within the mixing chamber. Typically, the mixing chamber is adapted to swirl the exhaust flow both clockwise and counterclockwise within the mixing chamber.

[0013] In another embodiment, the first guiding means comprise at least one bypass opening for guiding a portion of the exhaust gas flow directly to the downstream outlet of the housing, thereby bypassing the mixing chamber.

[0014] In another embodiment, the first guiding device comprises a cylindrical tube having a plurality of openings adapted to induce swirl in the exhaust flow, the cylindrical tube being positioned at the periphery of the mixing chamber. In one alternative, the first guiding device induces a clockwise swirl in the exhaust flow within the mixing chamber, while the second guiding device induces a counterclockwise swirl in the exhaust flow within the mixing chamber. In another embodiment, the first guiding device induces a counterclockwise swirl in the exhaust flow within the mixing chamber, while the second guiding device induces a clockwise swirl in the exhaust flow within the mixing chamber.

[0015] In another embodiment, the first guiding device comprises a spiral tube having at least one opening adapted to induce a vortex in the exhaust flow, the spiral tube being positioned at the periphery of the mixing chamber. In one alternative, the first guiding device induces a clockwise vortex in the exhaust flow within the mixing chamber, while the second guiding device induces a counterclockwise vortex in the exhaust flow within the mixing chamber. In another embodiment, the first guiding device induces a counterclockwise vortex in the exhaust flow within the mixing chamber, while the second guiding device induces a clockwise vortex in the exhaust flow within the mixing chamber.

[0016] In another embodiment, the second guide device is located at one end of the mixing chamber, directly opposite to the outlet of the mixing chamber, and forms a space that is part of the mixing chamber.

[0017] In another embodiment, the mixing chamber defines a longitudinal axis from at least one opening for introducing reductant into the mixing chamber to at least one outlet communicating with a downstream outlet of the housing for distributing the exhaust flow after mixing with the vaporized reductant.

[0018] In another embodiment, the mixing chamber comprises a cylindrical tube having a plurality of openings in an upper portion of the mixing chamber adjacent to the dosing module.

[0019] In another embodiment, the housing is L-shaped having an upstream inlet for receiving the exhaust flow and a downstream outlet for distributing the exhaust flow after mixing with the evaporated reductant, wherein the upstream inlet defines a first longitudinal axis and the downstream outlet defines a second longitudinal axis, wherein the first longitudinal axis is substantially perpendicular to the second longitudinal axis.

[0020] In another embodiment, the dosing module for introducing the reducing agent is arranged to introduce the reducing agent parallel to the longitudinal axis of the mixing chamber.

[0021] In another embodiment, the dosing module is selected from a pressure nebulizer or an air-assisted nebulizer.

[0022] In another embodiment, the dosing module further comprises an injection protection accessory.

[0023] In another embodiment, the apparatus of the present invention comprises a spray breakup device for impacting the liquid spray.

[0024] In one embodiment, the evaporated liquid reductant is an evaporated urea-water solution.

[0025] In a second aspect, the present invention relates to an aftertreatment system for exhaust gases from an internal combustion engine, characterized in that it comprises at least one device according to the present invention and any one of the above-described embodiments.

[0026] In an embodiment of the second aspect, the aftertreatment system further comprises a particulate filter, typically a DPF.

[0027] In another embodiment of the second aspect, the aftertreatment system further includes an SCR catalyst.

[0028] In another embodiment of the second aspect, the aftertreatment system further includes an oxidation catalyst, such as a DOC.

[0029] In another embodiment of the second aspect, the aftertreatment system further includes an ammonia slip catalyst.

[0030] In a third aspect, the present invention relates to the use of at least one device of the present invention and any one of the above-described embodiments for mixing an exhaust gas flow from an internal combustion engine with a vaporized liquid reducing agent.

[0031] In one embodiment, the internal combustion engine is a diesel engine.

[0032] In another embodiment, the internal combustion engine is an Otto engine.

[0033] In another embodiment, the internal combustion engine is an Atkinson engine.

[0034] In a fourth aspect, the present invention relates to a vehicle, characterized in that it comprises the aftertreatment system of the present invention and any one of the above-described embodiments.

[0035] In one embodiment, the vehicle is powered by a diesel engine.

[0036] In another embodiment, the vehicle is powered by an Otto engine.

[0037] In another embodiment, the vehicle is powered by an Atkinson engine.

[0038] In another aspect, the present invention relates to the use of at least one device according to the invention and any one of the above-described embodiments in connection with the construction of an exhaust gas aftertreatment system.

[0039] Other objects and advantages of the invention will appear from the following description and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is an exploded view of the various components and subassemblies of an embodiment of the evaporation and gas mixing device of the present invention.

[0041] Figure 2 The evaporation and gas mixing device of the present invention is shown as a 3D-shaped cross-section within a housing for receiving exhaust gases to be treated and mixed.

[0042] Figure 3 yes Figure 1 and Figure 2 A cross-sectional view of the liquid vaporization and gas mixing device of the present invention is shown.

[0043] Figure 4A Shows Figure 1 An embodiment wherein the conical top is connected and sealed to the bottom of the mixing chamber.

[0044] Figure 4B Shown Figure 4A An alternative to the embodiment in FIG.

[0045] Figure 5A yes Figure 1 and Figure 2 A top cross-sectional view of the liquid vaporization and gas mixing apparatus of the present invention is shown.

[0046] Figure 5B Shown Figure 5A An alternative to the embodiment in FIG. DETAILED DESCRIPTION

[0047] The present invention has numerous advantages in its broad context, as well as further advantageous aspects of its embodiments.

[0048] Achieving efficient evaporation of a liquid reductant (e.g., aqueous urea solution) from a dosing module, uniform mixing of the resulting reductant product (e.g., ammonia) into the exhaust gas, and subsequent uniform distribution over the catalytic components is a known problem in the field of the invention. Several prior art devices have been proposed to achieve this while minimizing the risk of urea deposits, minimizing backpressure, and minimizing space requirements.

[0049] The present invention, through the structure described in detail herein, provides an improvement over the prior art while distinguishing itself from existing devices. The result is a compact mixing system that meets the required functional requirements, yet is simple to manufacture, can be used with a variety of different dosing modules, axial dosing, multiple dosing modules, and can be scaled for different catalyst diameters.

[0050] As used herein, the term "reductant" refers to a reducing agent, for example, a liquid reducing agent such as an aqueous urea solution suitable for reducing harmful gases in internal combustion engines, such as DEF (diesel exhaust fluid).

[0051] As used herein, the term "longitudinal axis" refers to an imaginary axis within a housing that defines the direction of exhaust gas flow from the housing.

[0052] As used herein, the term "openings" refers to openings of any size, as long as they are large enough to facilitate exhaust gas flow, such as circular, polygonal, or other openings.

[0053] Now refer to the attached Figure 1 、 Figure 2 、 Figure 3 、 Figure 4A 、 Figure 4B 、 Figure 5A 、 Figure 5B (hereinafter referred to as Figure 1 -5) Describe the method and apparatus according to the present invention in more detail. The accompanying drawings illustrate one way of implementing the present invention and should not be interpreted as limiting the present invention in any way.

[0054] Figure 1 All parts shown in FIG5 can be produced by rolling the outer spiral, the inner tube can be produced by laser cutting and rolling, the cover can be produced by deep drawing, and the bottom can be laser cut. Finally, these parts can be connected together using welding, brazing or any other safe connection method known to those skilled in the art. The housing (32) can be produced by deep drawing.

[0055] The material used may be stainless steel having low thermal expansion, resistance to urea corrosion, good formability and weldability.

[0056] Figure 1 The present invention is an exploded view of the various components and subassemblies of an embodiment of an evaporation and gas mixing device. The evaporation and gas mixing device (10) consists of a conical top (12), a mixing chamber defined by a cylindrical tube (20), wherein the upper portion of the mixing chamber directly connected to the conical top is surrounded by an outer spiral portion (20), which produces a counterclockwise swirling airflow within the mixing chamber. The conical top (12) has two inlets (14, 16) for receiving exhaust gas and an opening (18) in the top for introducing a reducing agent during operation. In particular, the conical top (12) is designed to keep the nozzle tip clean. The mixing chamber has an inner cylindrical tube (20), the upper portion of which has a hole (24) and is surrounded by a spiral outer portion (22) in the upper portion, which is suitable for receiving exhaust gas into the spiral outer portion through an inlet (26), and the exhaust gas spirals into the mixing chamber through the hole (24) in the upper portion. In addition, a confining body (25) is provided which divides the exhaust gas into a flow passing through the top (12) and another flow entering the mixing chamber through the inlet (26). At the end of the exhaust gas flow exiting the mixing chamber, a through hole (29) is provided to help keep the trailing edge of the cylindrical tube (20) free of trapped liquid reductant.

[0057] Figure 2The evaporation and gas mixing device of the present invention is shown as a 3D-shaped cross-section within a housing (32) for receiving exhaust gases to be treated and mixed. The gas mixing device of embodiment (30) is located within the housing (32) having an upstream inlet at arrow (48) for receiving the exhaust gas flow, and a downstream outlet (44) for distributing the exhaust gas flow after mixing with the evaporation reducing agent from the metering inlet (42). The housing (32) has an L-shaped configuration having an upstream inlet for receiving the exhaust gas flow indicated by the inlet at arrow (48), the upstream inlet being perpendicular to the downstream outlet, the downstream outlet being for distributing the exhaust gas flow after mixing with the evaporation reducing agent indicated by the longitudinal axis (50) having the outlet (44). The evaporation and gas mixing device (10, as Figure 1 The evaporation and gas mixing device has a mixing chamber defined by a cylindrical tube (34) and a conical top (40). The cylindrical tube (34) is designed to adjust the swirl flow before leaving the outlet (44). The top conical portion (40) of the mixing chamber (34, 40) is at the top (18, Figure 1 ) has an opening for injecting and distributing a reducing agent (such as a liquid reducing agent, such as a urea aqueous solution) into the exhaust gas when the aftertreatment system is operated in an internal combustion engine in a vehicle (such as a diesel truck, etc.). When the evaporation and gas mixing device ( Figure 1 10) in operation, the opening (18, Figure 1 ) is equipped with a dosing module, which is arranged at one end of the mixing chamber (34, 40) opposite to the outlet (44) of the mixing chamber (34). The top (40) of the mixing chamber (34, 40) has two first openings (14, 16, such as Figure 1 The invention relates to a mixing chamber comprising a top portion (40) and a second guide device (20) for receiving the exhaust gas swirled when entering the openings (14, 16). Each of the two openings (14, 16) is provided with a second guide device (two second guide devices in this embodiment) adapted to receive the exhaust gas flow and guide it into the mixing chamber, wherein the exhaust gas flow is guided perpendicularly to the exhaust gas flow (50, 56) distributed from the outlet (44) of the mixing chamber (46), and wherein the top portion (40) (second guide device) has an opening (18, 19) for introducing the reducing agent into the mixing chamber via a dosing module (not shown). Figure 1 ), wherein the top opening (18, Figure 1 ) is in communication with the opening (42) of the housing (32). In the embodiment shown, the openings (18, 42) are centrally aligned along the longitudinal axis (50). Typically, the exhaust gas entering the inlet (14, 16) in the top (40) swirls clockwise as indicated by arrows (52) and mixes with the evaporated reducing agent through the opening (42). The exhaust gas further passes through the second inlet (26, as shown in the direction indicated by arrows (48) Figure 1The exhaust gas is directed to the mixing chamber through an inlet (26) defined by an axis (46) and in a direction indicated by an arrow (48). The second inlet opening (26) provides a first guide (in this embodiment, a first guide) adapted to receive the exhaust gas flow and direct it into the mixing chamber, wherein the exhaust gas flow is directed perpendicularly to the exhaust gas flow (50, 56) distributed from the outlet (44) of the mixing chamber (46). Alternatively, if the swirling gas from the inlet (26, 48) swirls clockwise, the exhaust gas entering the inlet (14, 16) of the top (40) swirls counterclockwise. The upper portion of the mixing chamber (34) facing the top conical mixing portion (40) is surrounded by an outer spiral portion (36), wherein the outer spiral portion induces a counterclockwise swirling gas flow (54) within the mixing chamber (34). Typically, as shown in the figure, the upper portion of the mixing chamber (34) has an opening or hole (38) for receiving the exhaust gas when the exhaust gas enters the inlet (26) and swirls through the space formed by the spiral outer portion (36) and the mixing chamber (34). The spiral outer portion (36) is directly connected to the inlet (26), and the exhaust gas is swirled when entering the mixing chamber. The first opening and the second opening (26) are here separated by the shielding element (25, Figure 1 ) to ensure that the exhaust gas is divided into two separate streams ( Figure 1 14, 16, Figure 2 26 and 48 in FIG). Preferably, as shown in the figure, the first flow portion of the exhaust gas enters the top mixing portion of the mixing chamber and swirls clockwise (52), while the second flow portion of the exhaust gas enters the inlet of the second opening (26) and swirls counterclockwise (54). The swirl creates a high-speed flow to aid evaporation, and the opposite swirl directions ensure good mixing of the gaseous materials.

[0058] Figure 3 yes Figure 1 and Figure 2 The cross-sectional view of the liquid evaporation and gas mixing device of the present invention is shown. In particular, the exhaust gas enters the housing (32) in the direction indicated by the arrow (48). Then, the exhaust gas is divided into two streams. The first exhaust gas stream passes through the top cyclone device (40) inlet ( Figure 114, 16) enters the evaporation and mixing device, and with the help of the top swirl device, the air flow is accelerated around the injection point, which helps evaporation and mixing between the gas and the reducing agent. The reducing agent is usually a urea aqueous solution, which is introduced into the exhaust gas as a spray through a reducing agent dosing module that is basically perpendicular to the exhaust gas inlet axis (46). The exhaust gas carrying gaseous ammonia and droplets from the top swirl device (40) enters the inner tube (34) in a clockwise swirl direction. Secondly, the exhaust gas flow enters the evaporation and mixing device through the swirl device inlet (26) and enters the mixing chamber (34) that is directly connected to the top swirl device (40). With the help of the swirl device (36), the air flow is accelerated around the inner tube (34), and the accelerated air flow passes through the inner tube and flows out through the outlet (44), which causes the air flow to adopt a (high-speed) swirl motion, which helps evaporation and mixing in the second direction. Typically, as shown in the figure, the upper part of the mixing chamber (34) has an opening or hole (38) for the exhaust gas to enter the inlet ( Figure 2 26) and receives the exhaust gas as it swirls through the space formed by the spiral outer part (36) and the mixing chamber (34). The tube extension helps to avoid deposition in the mixer outlet (44). When the first and second air flows of the exhaust gas from the top vortex device and the lower vortex device are mixed in the inner tube and forced toward the mixer outlet, a vortex motion in a clockwise or counterclockwise direction is maintained. The present invention can be used in conjunction with distribution, deflection and swirl baffle connection and continue to pass through the SCR catalyst. After leaving the outlet (44) and the mixing chamber (inner tube) (34), the air flow is reversed 180° through the guide device in the distribution unit (not shown). Thereafter, the air flow passes through the swirl baffle (not shown), which causes the air flow to adopt a swirl motion, which helps mixing and prevents the formation of a low pressure area behind the guide device. The uniformly mixed gaseous substances are processed by a selective catalytic reduction catalyst or an SCR filter catalyst.

[0059] Figure 4A Shows Figure 1 Embodiment (10) in which the conical top (12) is connected and sealed to a bottom portion consisting of a mixing chamber defined by a cylindrical tube (20), and wherein an upper portion of the mixing chamber directly communicating with the conical top is surrounded by an outer spiral portion (22), wherein the outer spiral portion induces a counterclockwise swirling airflow within the mixing chamber. The conical top (12) has two inlets (14, 16) for receiving exhaust gases and an opening (18) in the top portion for introducing a reducing agent during operation. The mixing chamber has an inner cylindrical tube (20) having a hole (29) in its lower portion for relieving a low pressure zone near the trailing edge of the cylindrical tube (20) and is surrounded by an upper spiral outer portion (22) adapted to receive exhaust gases through the inlet (26) into the spiral outer portion, the exhaust gases passing through the hole (38, Figure 2) swirls into the mixing chamber. In addition, a defining body (25) is provided which divides the exhaust gas into a flow passing through the top (12) and another flow entering the mixing chamber through the inlet (26).

[0060] Figure 4B Shown Figure 1 An alternative embodiment of (60) wherein the mixing chamber has an inner cylindrical tube 20 having holes (29) in its lower portion for relieving a low pressure zone near the trailing edge of the cylindrical tube (20) and is surrounded by an outer portion (63) of the upper portion adapted to receive exhaust gas to the exterior via rotating blades (62), the exhaust gas passing through the through holes (38, Figure 2 ) vortexed into the mixing chamber.

[0061] Figure 5A Shown as Figure 1 and Figure 2 A top cross-sectional view of the liquid vaporization and gas mixing device (70) of the present invention is shown. In particular, the outer spiral portion (76) directs a counterclockwise swirling airflow within the mixing chamber upon entering the opening (80).

[0062] Figure 5B yes Figure 1 and Figure 2 The top cross-sectional view of the liquid vaporization and gas mixing device (90) of the present invention is shown. In particular, the bypass hole (92) is shown as a bypass hole. Figure 5A Such bypass holes are designed to allow heat flux from the outside of the pipe extension to the inside of the pipe extension.

[0063] The liquid evaporation and gas mixing device of the present invention can be made by various production methods. Figure 1 -5 One embodiment of the device is described in more detail. The conical top and mixing chamber can each be composed of four parts: a laser-cut and rolled tube, a laser-cut and rolled outer helical portion, a pressed conical top, and a laser-cut defining body. The inner tube is welded to the defining body to form a first assembly. The formed outer helical portion is welded to the defining body of the first assembly, and the conical top is subsequently welded to the defining body of the assembly. Finally, the assembled components are installed and welded into a housing.

[0064] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0065] All headings and sub-headings are used herein for convenience only and should not be construed as limiting the invention in any way.

[0066] Any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

[0067] Unless otherwise indicated herein, recitation of ranges of values ​​herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, and each separate value is incorporated into the specification as if it were individually recited herein. Unless otherwise indicated herein, all exact values ​​provided herein represent corresponding approximate values ​​(e.g., all exact example values ​​provided with respect to a particular factor or measurement may also be considered to provide the corresponding approximate measurement, modified by "about" where appropriate).

[0068] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.

[0069] The terms "a," "an," "the," and similar designations used in the context of describing the present invention should be construed as inserting both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Thus, "a," "an," and "the" mean at least one or one or more terms that can be used interchangeably.

[0070] As used herein, the term "and / or" is intended to represent both alternatives as well as each alternative individually. For example, the expression "xxx and / or yyy" means "xxx and yyy; xxx; or yyy", with all three alternatives depending on the respective embodiment.

[0071] Unless otherwise specified, the use of any and all examples or exemplary language (e.g., "such as") provided herein is intended merely to better illuminate the invention and does not limit the scope of the invention. No language in the specification should be construed as indicating any element is essential to the practice of the invention unless expressly stated otherwise.

[0072] The citation and incorporation of patent documents herein is for convenience only and does not reflect any opinion regarding the validity, patentability and / or enforceability of such patent documents.

[0073] The use of terms such as “comprising,” “having,” “including,” or “containing” herein to describe any aspect or embodiment of the invention with reference to one or more elements is intended to provide support for similar aspects or embodiments of the invention “consisting of,” “consisting essentially of,” or “consisting essentially of” that particular element, unless otherwise specified or clearly contradicted by context (e.g., a composition described herein comprising a particular element should be understood to also describe a composition consisting of that element, unless otherwise specified or clearly contradicted by context).

[0074] To the maximum extent permitted by applicable law, this invention includes all modifications and equivalents of the subject matter recited in the aspects or claims set forth herein.

[0075] The features disclosed in the above description may, alone or in any combination, be material for realizing various forms of the invention.

Claims

1. An evaporation and gas mixing device for an exhaust gas aftertreatment system, the device being used to mix an exhaust gas flow from the exhaust gas aftertreatment system with an evaporated reducing agent, the device comprising: a) a housing having an upstream inlet for receiving the exhaust gas flow and a downstream outlet for distributing the exhaust gas flow after mixing with the vaporized reductant; b) a mixing chamber within the housing, the mixing chamber being configured to swirl the exhaust gas flow and the evaporated reductant for mixing within the mixing chamber, the mixing chamber having at least one opening for introducing the reductant into the mixing chamber, and having at least two separate inlets for receiving the exhaust gas flow and at least one outlet communicating with the downstream outlet of the housing for distributing the exhaust gas flow after mixing with the evaporated reductant; c) a dosing module for introducing the reducing agent into the mixing chamber through the at least one opening in order to evaporate and mix with the exhaust gas flow, wherein the dosing module is arranged at an end of the mixing chamber opposite the at least one outlet of the mixing chamber; d) a first guide device positioned within the housing, the first guide device having at least one inlet adapted to receive the exhaust flow and guide the exhaust flow to the mixing chamber, wherein the exhaust flow is guided perpendicular to the exhaust flow distributed from the at least one outlet of the mixing chamber; e) a second guide device located within the housing, the second guide device being arranged at an end of the mixing chamber opposite the at least one outlet of the mixing chamber, the second guide device having at least one inlet adapted to receive the exhaust flow and guide the exhaust flow into the mixing chamber; wherein the exhaust gas flow is directed perpendicularly to the exhaust gas flow distributed from the at least one outlet of the mixing chamber, and wherein the second guiding device has an opening for introducing the reducing agent into the mixing chamber.

2. The apparatus of claim 1, wherein the mixing chamber is adapted to swirl the exhaust flow clockwise and / or counterclockwise within the mixing chamber.

3. The device according to any one of claims 1-2, wherein the first guiding means comprises at least one bypass opening for guiding a portion of the exhaust gas flow directly to the downstream outlet of the housing, thereby bypassing the mixing chamber.

4. The device according to any one of claims 1 to 3, wherein the first guide device comprises a cylindrical tube having a plurality of openings adapted to induce swirl in the exhaust gas flow, the cylindrical tube being located on the outer periphery of the mixing chamber.

5. The device according to any one of claims 1 to 3, wherein the first guiding device comprises a spiral tube having at least one opening adapted to induce swirl in the exhaust gas flow, the spiral tube being located on an outer periphery of the mixing chamber.

6. The device according to any one of claims 4 to 5, wherein the first guide device causes the exhaust gas flow to swirl clockwise in the mixing chamber, and the second guide device causes the exhaust gas flow to swirl counterclockwise in the mixing chamber.

7. The device according to any one of claims 4 to 5, wherein the first guide device causes the exhaust gas flow to swirl counterclockwise in the mixing chamber, and the second guide device causes the exhaust gas flow to swirl clockwise in the mixing chamber.

8. The device according to any one of claims 1 to 7, wherein the second guide device is located at the top of the mixing chamber directly opposite to the outlet of the mixing chamber and forms a space as a part of the mixing chamber.

9. The apparatus of any one of claims 1-8, wherein the mixing chamber defines a longitudinal axis extending from the at least one opening for introducing the reductant into the mixing chamber to at least one outlet communicating with the downstream outlet of the housing for distributing the exhaust flow after mixing with the evaporated reductant.

10. The device according to any one of claims 1 to 9, wherein the mixing chamber comprises a cylindrical tube having a plurality of openings in an upper portion of the mixing chamber adjacent to the dosing module.

11. The apparatus of any one of claims 1-10, wherein the housing is L-shaped, the housing having the upstream inlet for receiving the exhaust flow and the downstream outlet for distributing the exhaust flow after mixing with the evaporated reductant, wherein the upstream inlet defines a first longitudinal axis and the downstream outlet defines a second longitudinal axis, wherein the first longitudinal axis is substantially perpendicular to the second longitudinal axis. 12 . The device according to claim 1 , wherein the dosing module for introducing the reducing agent is arranged to introduce the reducing agent parallel to the longitudinal axis of the mixing chamber.

13. The device according to any one of claims 1 to 12, wherein the dosing module is selected from a pressure nebulizer or an air-assisted nebulizer.

14. The device according to any one of claims 1 to 12, wherein the dosing module further comprises an injection protection accessory.

15. Apparatus according to any one of claims 1 to 10, comprising spray break-up means for impacting the liquid spray.

16. A post-treatment system for exhaust gas from an internal combustion engine, characterized in that It comprises at least one device according to any one of the preceding claims.

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