Exhaust fluid filter with a medium for detecting hydrocarbons

Abstract

Method for detecting hydrocarbons in a post-treatment system (100) with a reducing agent container (110) and a hydrocarbon detection device (140, 240) coupled to the reducing agent container, wherein the method comprises: Allowing the reducing agent in the reducing agent container to act on the hydrocarbon detection device; and Determine that the hydrocarbon detection device has provided an indication of the presence of a hydrocarbon in the reducing agent in the reducing agent container, wherein allowing the reducing agent in the reducing agent container (110) to act on the hydrocarbon detection device (140, 240) includes allowing the reducing agent in the hydrocarbon detection device to act on a hydrophobic paper.

Description

Technical field

[0001] The present disclosure relates generally to exhaust aftertreatment systems for use with internal combustion engines (IC engines). background

[0002] During the combustion process in an internal combustion engine (for example, a diesel engine), sulfur is simultaneously released along with carbon monoxide (CO) and hydrocarbons (HC), such as various sulfur oxides (SO₄). x ). formed. Typically, 97-99% of the total amount of SO₂ present in the exhaust gas consists of SO₂. x Sulfur dioxide (SO2) and 1-3% sulfur trioxide (SO3) are present. Fuels with a higher sulfur content tend to produce larger amounts of SO3. For example, a fuel with a sulfur content of 1000 ppm can form approximately 1-3 ppm SO3.

[0003] Exhaust aftertreatment systems are used to capture and treat exhaust gases produced by internal combustion engines. Conventional exhaust aftertreatment systems incorporate any number of several different components to reduce the proportion of harmful exhaust emissions. For example, certain exhaust aftertreatment systems for diesel-powered internal combustion engines include a selective catalytic reduction (SCR) catalyst to convert NOₓ. x(NO and NO2 in minor proportions) are converted into harmless nitrogen gas (N2) and water vapor (H2O) in the presence of ammonia (NH3). Generally, in such conventional aftertreatment systems, an exhaust reducing agent (e.g., a diesel exhaust fluid such as urea) is injected into the aftertreatment system to provide an ammonia source and mixed with the exhaust gas to partially reduce the SOx and / or NOx gases. The byproducts of exhaust gas reduction are then conveyed by flow to the catalyst incorporated into the SCR aftertreatment system to essentially decompose all SOx and NOx gases into relatively harmless byproducts, which are then emitted from such conventional SCR aftertreatment systems. A major cause of malfunctions and failures in conventional SCR systems is contamination of the exhaust reducing agent with hydrocarbons. For example, the exhaust reducing agent can be contaminated with diesel fuel, injector cleaner (e.g., urea), or other contaminants.Hydrocarbons can contaminate the exhaust reducing agent (e.g., toluene) or engine oil. These hydrocarbons can overheat the SCR catalyst, degrade the ethylene propylene diene monomer (EPDM) seals in the exhaust reducing agent tank or pump, attack the coatings in the exhaust reducing agent tank and lines, and even cause the exhaust reducing agent pump diaphragm to swell. Approximately 37% to 50% of all SCR aftertreatment system failures can be attributed to hydrocarbon contamination. This results in a significant number of warranty claims from customers, as it is not always possible to determine whether the SCR aftertreatment system failure is due to hydrocarbon contamination, which can be attributed to the customer's lack of control.

[0004] From WO 2010 / 077 188 A1, a urea level measuring device, particularly for use in a vehicle's urea tank, is known, comprising measuring units. The article "Detection of fuel in AdBlue tanks with oil test paper" from "Camlab's blog and information database" concerns testing the urea solution "AdBlue" for the presence of fuel. DE 10 2008 053 ​​026 A1 relates to a device, a system, and a method for a filter for filtering a metering fluid in an exhaust gas treatment system. Summary

[0005] The embodiments described here relate to methods for detecting hydrocarbons in exhaust aftertreatment systems and to exhaust aftertreatment systems for use with internal combustion engines according to the preambles of claims 1, 6, 12, 17 and 18. Different embodiments are defined by the dependent claims. Brief description of the drawings

[0006] The foregoing and further features of the present disclosure will become clearer with reference to the following description and the attached claims, which should be read in conjunction with the accompanying drawings. Provided that these drawings represent only some implementations in accordance with the disclosure and are therefore not to be considered limiting in scope, the disclosure is described with additional precision and detail by means of the accompanying drawings. Fig. Figure 1 is a schematic block diagram of a post-treatment system that includes a hydrocarbon detection device according to one embodiment. Fig. Figure 2A is a side view of an exhaust gas reducing agent filter comprising a hydrocarbon detection device arranged on a side wall of the filter according to one embodiment; and Fig. 2B shows a color change experience in the hydrocarbon detection device from Fig. 2A in the presence of an exhaust gas reducing agent contaminated with hydrocarbons. Fig. Figure 3 is a schematic flowchart of a method for detecting the presence of a hydrocarbon in an exhaust gas reducing agent using a hydrocarbon detection device according to one embodiment. Fig. Figure 4A shows a hydrocarbon detection device enclosing a hydrophobic paper exposed to an uncontaminated diesel emission fluid; and Fig. 4B shows the hydrocarbon detection device Fig. 4A after a brief exposure to a diesel emission fluid contaminated with diesel fuel.

[0007] The entire following detailed description refers to the accompanying drawings. In the drawings, similar symbols typically denote similar components unless the context indicates otherwise. The illustrative representations described in the detailed description, drawings, and claims are not intended to be limiting. Other embodiments may be used, and other modifications may be made without departing from the fundamental concept or scope of protection of the subject matter presented here. It is understood that the aspects of this disclosure, as generally described herein and illustrated in the drawings, can be arranged, substituted, combined, and designed in many different configurations, all of which are expressly considered and form part of this disclosure. Detailed description of various designs

[0008] The embodiments described here relate generally to exhaust aftertreatment systems for use with internal combustion engines, in particular exhaust aftertreatment systems that include an exhaust reducing agent filter with a hydrocarbon detection device. The embodiments described here can provide several advantages over conventional aftertreatment systems, including, for example: (1) visual diagnosis of hydrocarbon contaminants in exhaust reducing agents (e.g.,(1) diesel emission fluid) by observing a color change of the hydrocarbon detection device; (2) the ability to detect very low concentrations of hydrocarbons in the exhaust reducing agent; (3) easy adaptability to conventional aftertreatment systems without significant modifications to the conventional aftertreatment systems; and (4) providing clarification as to whether any damage to aftertreatment systems is due to the presence of hydrocarbons in the exhaust reducing agent, which is based on user error and is not covered by the warranty, thereby reducing the number of erroneous warranty claims.

[0009] Fig. Figure 1 shows an aftertreatment system 100 that can be used to treat exhaust gas (e.g., diesel exhaust) produced by an internal combustion engine (e.g., a diesel engine), according to one embodiment. The aftertreatment system 100 comprises an exhaust gas reducing agent tank 110, a filter 130, a hydrocarbon detection device 140, and an SCR system 150. The aftertreatment system 100 can be used with any type of internal combustion engine, for example, diesel engines (e.g., vehicle diesel engines, marine engines, industrial power generator diesel engines, etc.).

[0010] The exhaust gas reducing agent container 110 is designed to store exhaust gas reducing agent and is fluidly coupled to the filter 130. In some embodiments, the exhaust gas reducing agent container 110 may include a diesel emission fluid container, and the exhaust gas reducing agent may include a diesel exhaust fluid. The diesel emission fluid may comprise urea, an aqueous urea solution, or any other ammonia-containing fluid, byproducts, or any other diesel emission fluids known from the prior art (e.g., the diesel emission fluid marketed under the name ADBLUE®).

[0011] In some embodiments, the aftertreatment system 100 may also include an exhaust gas reducing agent pump (not shown). In such embodiments, the exhaust gas reducing agent pump may be fluidly coupled to the SCR system 150. The exhaust gas reducing agent pump may be configured to pump the exhaust gas reducing agent from the exhaust gas reducing agent reservoir 110 to the SCR system 150 through the filter 130. The exhaust gas reducing agent pump may comprise any suitable pump, for example, a diaphragm pump, a centrifugal pump, a positive displacement pump, a vacuum pump, or a combination thereof. In some embodiments, the operation of the exhaust gas reducing agent pump may be controlled by a control system (e.g., an electronic control unit) to supply a known or otherwise determined quantity of an exhaust gas reducing agent to the SCR system 150.

[0012] Filter 130 is designed to filter out any particles from the exhaust gas reducing agent, such as dust, organic particles, crystals (e.g., urea crystals), or any other solid particles present in the exhaust gas reducing agent before it is fed to the SCR system 150. Filter 130 may include a housing made of a solid and rigid material, such as high-density polypropylene (HDPP), which can define an internal volume to accommodate a filter element. Any suitable filter element may be used, such as a cotton filter element, an acrylonitrile butadiene styrene (ABS) filter element, any other suitable filter element, or a combination thereof. The filter element may have any suitable pore size, for example, approximately 10 microns, approximately 5 microns, or approximately 1 micron.

[0013] The hydrocarbon detection device 140 is designed to indicate the presence of hydrocarbons in the exhaust gas reducing agent. In some embodiments, the hydrocarbon detection device 140 may include a hydrophobic paper (e.g., filter paper). The hydrophobic paper may be conventional paper (e.g., cellulose paper) coated with a hydrophobic coating, such as wax, styrene-maleic anhydride copolymers, siloxane, GREENCOAT®, or any other suitable coating or combination thereof. In some embodiments, the hydrocarbon detection device 140 may consist of nylon, acrylonitrile butadiene styrene (ABS), polycarbonates, cellulose, and / or polymethyl methacrylate.

[0014] The hydrocarbon detection device 140 can be configured to change color when a hydrocarbon present in the exhaust reducing agent (e.g., diesel emission fluid), such as diesel fuel, injector fluid, or oil, acts upon it. For example, the hydrocarbon detection device 140 can include hydrophobic paper that incorporates hydrophobic nonpolar groups on its surface, which repel aqueous solutions free of hydrocarbons. For example, the exhaust reducing agent may be diesel emission fluid, which is generally an aqueous urea solution. Therefore, the hydrophobic paper repels the uncontaminated diesel emission fluid, which is why the diesel emission fluid cannot wet or moisten the hydrophobic paper. However, if the diesel emission fluid is contaminated with hydrocarbons (e.g.,If diesel fuel is contaminated, the hydrocarbons are attracted to the hydrophobic, non-polar groups of the hydrophobic paper (e.g., deposited on the surface of the hydrophobic paper). The hydrocarbons are then absorbed by the hydrophobic paper, forming a film on its surface or moistening it in some other way, causing the hydrophobic paper to change color. This color change indicates that the diesel emission fluid is contaminated with hydrocarbons.

[0015] In some embodiments, the hydrocarbon detection device 140 can be arranged within the filter 130. For example, the hydrocarbon detection device 140 can be arranged on an inner surface of a side wall of the filter 130. Furthermore, the hydrocarbon detection device 140 can include a strip of hydrophobic paper arranged on an inner surface of a side wall of the filter 130. In such embodiments, the side wall of the filter 130 can be made of a transparent or translucent material, allowing the strip of hydrophobic paper to be observed through the side wall of the filter. Any color change of the hydrophobic paper can thus be attributed to the presence of one or more hydrocarbons in the exhaust gas reducing agent, as described herein.

[0016] In some embodiments, the hydrocarbon detection device 140 can be enclosed within a filter element of the filter 130. For example, the hydrocarbon detection device 140 (e.g., the hydrophobic paper) can be ground into particles or powder and packed into the filter 130 along with the filter element. In such embodiments, the exhaust gas reducing agent can act on the hydrocarbon detection device 140 as it flows through the filter element of the filter 130. If hydrocarbon contaminants are present in the exhaust gas reducing agent, the hydrocarbon detection device 140 enclosed in the filter element changes color, which may appear as if the filter element itself is changing color. This indicates that the exhaust gas reducing agent is contaminated with hydrocarbons.

[0017] In some embodiments, the hydrocarbon detection device 140 can be arranged in the exhaust gas reducing agent container 110. For example, the hydrocarbon detection device 140 can include a strip of hydrophobic paper arranged on an inner surface of a side wall of the exhaust gas reducing agent container 110. In such embodiments, the side wall of the exhaust gas reducing agent container 110 can be made of a completely or partially transparent or translucent material to allow observation of the hydrocarbon detection device 140 through a side wall of the exhaust gas reducing agent container 110.

[0018] In some embodiments, the hydrocarbon detection device 140 can be arranged in both the filter 130 and the exhaust gas reducing agent container 110. In some embodiments, one or more side walls of the filter 130 and / or the exhaust gas reducing agent container 110 can be made of a hydrophobic material, such that the side wall of the filter 130 and / or the exhaust gas reducing agent container 110 serves as the hydrocarbon detection device 140.

[0019] The hydrocarbon detection device 140 described herein can be configured to detect very low concentrations of hydrocarbon impurities present in the exhaust gas reducing agent (e.g., diesel exhaust fluid). In some embodiments, the hydrocarbon detection device 140 can be configured to detect the presence of hydrocarbons in the exhaust gas reducing agent at concentrations of less than approximately 0.1 wt.%. For example, the hydrocarbon detection device 140 can be configured to detect the presence of hydrocarbons in the exhaust gas reducing agent at a concentration of less than approximately 1 wt.%, for example, approximately 0.9 wt.%, 0.8 wt.%, 0.7 wt.%, 0.6 wt.%, 0.5 wt.%, 0.4 wt.%, 0.3 wt.%, 0.2 wt.%, 0.1 wt.%, 0.05 wt.%, or approximately 0.025 wt.%, including all intermediate ranges and values.

[0020] The SCR system 150 is designed to treat exhaust gas (e.g., diesel exhaust) flowing through it. The SCR system 150 may include an injection port configured to direct the exhaust gas reducing agent received from the exhaust gas reducing agent reservoir 110, via the filter 130 (e.g., pumped by the exhaust gas reducing agent pump), into one or more chambers of the SCR system 150. The exhaust gas reducing agent reacts with the exhaust gas to at least partially reduce one or more components of the gas (e.g., SOx and NOx) or to promote the reduction of one or more components in the presence of one or more catalysts.

[0021] The SCR system 150 comprises one or more catalysts designed to selectively reduce exhaust gas emissions. Any suitable catalyst can be used, such as a platinum-, palladium-, rhodium-, cerium-, iron-, manganese-, copper-, or vanadium-based catalyst, or any other suitable catalyst, or a combination thereof. The catalyst can be mounted on a suitable substrate, such as a ceramic (e.g., cordierite) or metallic (e.g., Kanthal) monolithic core, which may, for example, have a honeycomb structure. A washcoat (intermediate layer) can also be used as a support material for the catalysts. Such washcoat materials may include, for example, aluminum oxide, titanium dioxide, silicon dioxide, any other suitable washcoat material, or a combination thereof. The exhaust gas (e.g.,Diesel exhaust gas can flow over and around the catalyst in such a way that all SOx or NOx gases contained in the exhaust gas are further reduced, resulting in an exhaust gas that is essentially free of carbon monoxide and SOx or NOx gases.

[0022] In some embodiments, a hydrocarbon detection device can be arranged in a filter that is enclosed in a post-treatment system. Fig. 2A and Fig. Figure 2B shows, for example, side views of a filter 230, which contains a hydrocarbon detection device 240 arranged in the filter 230. The filter 230 can be integrated into any aftertreatment system, for example, the aftertreatment system 100 or any other aftertreatment system designed to treat exhaust gases (e.g., diesel exhaust gases).

[0023] The filter 230 is designed to receive exhaust gas reducing agent (e.g., diesel emission fluid) from an exhaust gas reducing agent container enclosed in the aftertreatment system and to filter out particles (e.g., dust, organic particles, crystals (e.g., urea crystals), etc.) from the exhaust gas reducing agent before it is fed to the SCR system integrated in the aftertreatment system. The filter 230 includes a housing 232, which defines an internal volume. A filter element 234 is arranged within the internal volume defined by the housing 232. This filter element is designed to filter out particles from the exhaust gas reducing agent. For example, the filter element 234 can be arranged within the internal volume such that the exhaust gas reducing agent can flow through the filter element 234, but particles remain trapped within the filter element 234.Filter element 234 can include any suitable filter element capable of filtering particles from the exhaust gas reducing agent before the exhaust gas reducing agent is fed to the SCR system. Filter element 234 can be made of any suitable material, such as cotton, acrylonitrile butadiene styrene (ABS), any other suitable material, or a combination thereof. Furthermore, filter element 234 can have any suitable pore size, for example, approximately 10 micrometers, approximately 5 micrometers, or approximately 1 micrometer.

[0024] The hydrocarbon detection device 240 is designed to indicate the presence of hydrocarbons in the exhaust gas reducing agent. For example, the hydrocarbon detection device 240 may be designed to change color when a hydrocarbon present in the exhaust gas reducing agent acts upon it. In some embodiments, the hydrocarbon detection device 240 may contain a strip of hydrophobic paper, such as filter paper, cellulose paper coated with a hydrophobic coating (e.g., wax, styrene-maleic anhydride copolymers, siloxane, GREENCOAT®, or any other suitable coating or combination thereof), or any other suitable hydrophobic paper. In some embodiments, the hydrocarbon detection device may consist of nylon, acrylonitrile butadiene styrene (ABS), polycarbonates, cellulose, and / or polymethyl methacrylate.The hydrocarbon detection device 240 can be arranged on an inner surface of a side wall of the filter 230 such that an exhaust gas reducing agent flowing through the filter can act on the hydrocarbon detection device 240. The side wall of the filter 230 can be transparent or translucent, so that the hydrocarbon detection device 240 can be visually observed through the side wall of the filter 230.

[0025] In a Fig. In the first case shown in Figure 2A, an uncontaminated exhaust gas reducing agent (e.g., urea diesel exhaust fluid) flows through the filter 230. The uncontaminated exhaust gas reducing agent does not wet or otherwise moisten the hydrocarbon detection device 240, so the hydrocarbon detection device 240 does not change color. In a Fig. In the second case shown in Figure 2B, an exhaust gas reducing agent contaminated with hydrocarbons (e.g., diesel fuel, injector fluid, and / or oil) flows through the filter 230. In such cases, the hydrocarbons present in the exhaust gas reducing agent can moisten, adhere to, stick to, or otherwise form a film on the hydrocarbon detection device 240, causing the hydrocarbon detection device 240 to change color. For example, the hydrocarbon detection device 240 may be light-colored in the first case, while in the second case, it may be dark-colored. The color change can be visually perceived through the side wall of the filter 230 and thus indicates that the exhaust gas reducing agent is contaminated with one or more hydrocarbons.

[0026] While the hydrocarbon detection device 240 in the Fig. 2A and Fig. 2B, which is shown arranged on a side wall of the filter 230, can in some embodiments be integrated into the filter element 234 of the filter 230, as described herein with reference to the hydrocarbon detection device 140 enclosed in the system 100. In such embodiments, the hydrocarbon detection device 240 integrated into the filter element 234 changes its color in the presence of hydrocarbons such that it appears as a color change of the entire filter element 232. Furthermore, the hydrocarbon detection device 240 can be designed to detect the presence of hydrocarbons in the exhaust gas reducing agent at very low concentrations. In some embodiments, the hydrocarbon detection device 240 can be configured to detect the presence of hydrocarbons in the exhaust gas reducing agent at a concentration of less than about 1 wt.-% to demonstrate, for example, approximately 0.9 wt.%, 0.8 wt.%, 0.7 wt.%, 0.6 wt.%, 0.5 wt.%, 0.4 wt.%, 0.3 wt.%, 0.2 wt.%, 0.1 wt.%, 0.05 wt.% or approximately 0.025 wt.-%, including all intermediate ranges and values.

[0027] Fig. Figure 3 is a schematic flow diagram of an example method 300 for the detection of hydrocarbons in an exhaust gas reducing agent (e.g., a diesel emission fluid as described herein) flowing through an aftertreatment system, employing a hydrocarbon detection device. Method 300 can be used in conjunction with any aftertreatment system, such as aftertreatment system 100, and can be integrated into any aftertreatment procedure or process.

[0028] Method 300 involves passing an exhaust gas reducing agent through an exhaust gas reducing agent filter 302. The exhaust gas reducing agent may be a diesel emission fluid (e.g., an aqueous urea solution) or any other exhaust gas reducing agent as described herein. The exhaust gas reducing agent filter includes a housing that defines an internal volume. A filter element is arranged within the internal volume, which is configured to filter out particles from an exhaust gas reducing agent flowing through the filter element. The filter element may include any suitable filter element as described herein with respect to filters 130, 230, or with respect to any other filter described herein.

[0029] A hydrocarbon detection device is arranged within the internal volume of the exhaust gas reducing agent filter. The hydrocarbon detection device is designed to indicate the presence of hydrocarbons in the exhaust gas reducing agent. The hydrocarbon detection device may be substantially similar to hydrocarbon detection device 140, 240, or any other hydrocarbon detection device described herein. In some embodiments, the hydrocarbon detection device may comprise a hydrophobic paper (e.g., as described with respect to hydrophobic detection device 140 or 240). In some embodiments, the hydrocarbon detection device may be arranged on an inner surface of a side wall of the exhaust gas reducing agent filter.In such embodiments, the side wall of the exhaust gas reducing agent filter can be transparent or translucent to allow visual inspection of the hydrocarbon detection device through the side wall.

[0030] Procedure 300 further includes observing a potential color change of the hydrocarbon detection device at 304. The color change indicates the presence of a hydrocarbon in the exhaust reducing agent. It is then determined at 306 whether the hydrocarbon detection device has changed color. If the hydrocarbon detection device has not changed color, no action is performed and procedure 300 returns to action 302. However, if the hydrocarbon detection device has changed color, the exhaust reducing agent filter at 308 is replaced.

[0031] Method 300 can enable the detection of hydrocarbons in diesel exhaust fluid at very low concentrations. For example, the hydrocarbon detection device can be configured to detect the presence of hydrocarbons in diesel exhaust fluid at a concentration of less than approximately 1 wt%, for example, approximately 0.9 wt%, 0.8 wt%, 0.7 wt%, 0.6 wt%, 0.5 wt%, 0.4 wt%, 0.3 wt%, 0.2 wt%, 0.1 wt%, 0.05 wt%, or approximately 0.025 wt%, including all intermediate ranges and values. Hydrocarbon detection device with hydrophobic paper

[0032] Fig. Figure 4A shows a hydrocarbon detection device enclosing a strip of hydrophobic paper. The hydrophobic paper is cellulose paper with a wax coating. In its dry state, the hydrophobic paper was light blue. A diesel emission fluid, comprising approximately 33 wt% urea dissolved in water and containing no hydrocarbons, was poured onto the hydrophobic paper. The diesel emission fluid did not moisten the hydrophobic paper, and no color change of the hydrophobic paper was observed, as shown in Figure 4A. Fig.Figure 4A shows the process. The same diesel emission fluid, this time contaminated with approximately 0.05 wt% diesel fuel, was then poured over the hydrophobic paper. The hydrophobic paper changed color to dark blue after contact with the contaminated diesel emission fluid. This demonstrates that the hydrophobic paper can be used as a detection medium for hydrocarbons in diesel emission fluid.

[0033] As used herein, the terms "about" and "approximately" generally mean plus or minus 10% of the stated value. For example, "about 0.5" would include the values ​​0.45 and 0.55, "about 10" would include 9 to 11, and "about 1000" would include 900 to 1100.

[0034] The singular forms "ein / eine" and "der / die / das" used herein also include the plural forms, unless the context explicitly states otherwise. Therefore, for example, the term "ein Element" should mean a single element or a combination of elements, and "ein Material" should mean one or more materials or a combination thereof.

[0035] It should be noted that the term "exemplary", as used here to describe various embodiments, is intended to indicate that such embodiments are possible examples, representations and / or illustrations of possible embodiments (and that such a term is not necessarily intended to imply that such embodiments are exceptional or outstanding examples).

[0036] The terms "coupled," "connected," and the like, as used here, mean the direct or indirect connection of two elements. This connection can be stationary (e.g., permanent) or movable (e.g., removable or detachable). This connection can be achieved by the two elements, or the two elements and any further intermediate elements, being integrally formed as a single, unified body, or by the two elements, or the two elements and any further intermediate elements, being attached to one another.

[0037] It should be noted that the construction and arrangement of the various exemplary embodiments serve only for illustrative purposes. Although only some embodiments have been described in detail in this disclosure, those skilled in the art will readily recognize upon reading this disclosure that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and sections of the various elements, values ​​of parameters, assembly arrangements, use of materials, colors, orientations, etc.) without significantly deviating from the novel teachings and advantages of the subject matter described herein. Further substitutions, modifications, changes, and omissions can also be made in the design, operating conditions, and arrangement of the various exemplary embodiments without deviating from the scope of the present invention. Reference symbol list 100 aftercare system 110 Exhaust gas reducing agent tanks 130, 230 filters 140, 240 Hydrocarbon detection device 150 SCR system 232 cases 234 Filter element

Claims

[1] A method for detecting hydrocarbons in an aftertreatment system (100) having a reducing agent tank (110) and a hydrocarbon detection device (140, 240) coupled to the reducing agent tank, the method comprising: Allowing the reducing agent in the reducing agent container to act on the hydrocarbon detection device; and Determining that the hydrocarbon detection device has provided an indication of the presence of a hydrocarbon in the reductant in the reductant container, wherein the reducing agent in the reducing agent container (110) acts on the hydrocarbon detection device (140, 240) comprises the reducing agent in the hydrocarbon detection device acting on a hydrophobic paper. [2] The method of claim 1, further comprising the steps of: Flowing the reducing agent through an exhaust gas reducing agent filter (130, 230); and Changing the exhaust reductant filter (130, 230) in response to determining that the hydrocarbon detection device has provided the indication. [3] The method of claim 1, wherein the indication is a color change. [4] The method of claim 3, wherein the hydrocarbon detection device (140, 240) is configured to provide the indication in response to absorbing a hydrocarbon. [5] The method of claim 1, wherein the hydrocarbon detection device (140, 240) is configured to provide the indication in response to the reducing agent having a concentration of the hydrocarbon between 0.025 wt% and 1 wt% inclusive. [6] A method for detecting hydrocarbons in an aftertreatment system (100) having a reductant filter (130, 230) and a hydrocarbon detection device (140, 240) coupled to the reductant filter, the method comprising: Allowing the reducing agent in the reducing agent filter to act on the hydrocarbon detection device; and Determining that the hydrocarbon detection device has provided an indication of the presence of a hydrocarbon in the reductant in the reductant filter, wherein determining that the hydrocarbon detection device (140, 240) has provided the indication comprises observing the hydrocarbon detection device through a portion of a sidewall of the reductant filter (130, 230), the portion being transparent or translucent. [7] The method of claim 6, further comprising changing the hydrocarbon detection device (140, 240) in response to determining that the hydrocarbon detection device has provided the indication. [8] The method of claim 6, wherein: the display is a color change; and the hydrocarbon detection device (140, 240) is configured to provide the indication in response to absorbing a hydrocarbon. [9] The method of claim 6, wherein exposing the reducing agent in the reducing agent filter (130, 230) to the hydrocarbon detection device (140, 240) comprises exposing the reducing agent in the hydrocarbon detection device to a hydrophobic paper. [10] The method of claim 6, wherein the hydrocarbon detection device (140, 240) is arranged on an inner surface of a side wall of the reductant filter (130, 230). [11] The method of claim 6, wherein the hydrocarbon detection device (140, 240) is configured to provide the indication in response to the reducing agent having a concentration of the hydrocarbon between 0.025 wt% and 1 wt% inclusive. [12] Aftertreatment system (100) comprising: a reductant filter (130, 230) comprising a reductant filter sidewall and a housing defining an internal volume; a reducing agent container (110) comprising a side wall of the reducing agent container; and a hydrophobic paper which provides an indication of the presence of a hydrocarbon in the reducing agent upon contact with the reducing agent, wherein the hydrophobic paper comprises at least one of: Arrangement on an inner surface of the side wall of the reducing agent filter; Coupling with the side wall of the reducing agent filter; Arrangement in the internal volume; Arrangement on an inner surface of the side wall of the reducing agent container; or Coupling with the side wall of the reducing agent tank. [13] Aftertreatment system (100) according to claim 12, wherein: the hydrophobic paper is arranged on an inner surface of the side wall of the reducing agent container and / or coupled to the side wall of the reducing agent container; the side wall of the reducing agent container is partially or completely transparent or translucent. [14] Aftertreatment system (100) according to claim 12, wherein: the hydrophobic paper is arranged in the side wall of the reductant filter and / or coupled to the side wall of the reductant filter; the side wall of the reducing agent filter is partially or completely transparent or translucent. [15] The aftertreatment system (100) of claim 12, wherein the hydrophobic paper is configured to provide the indication in response to the reducing agent having a concentration of the hydrocarbon between 0.025 wt% and 1 wt% inclusive. [16] Aftertreatment system (100) according to claim 12, wherein: the display is a color change; and the hydrophobic paper comprises at least one of nylon, acrylonitrile butadiene styrene, polycarbonate, cellulose, a cellulose paper coated with a hydrophobic coating, or polymethyl methacrylate. [17] A method for detecting hydrocarbons in an aftertreatment system (100) having a reductant filter (130, 230) and a hydrocarbon detection device (140, 240) coupled to the reductant filter, the method comprising: Allowing the reducing agent in the reducing agent filter to act on the hydrocarbon detection device; and Determining that the hydrocarbon detection device has provided an indication of the presence of a hydrocarbon in the reductant in the reductant filter, wherein the reducing agent in the reducing agent filter (130, 230) is exposed to the hydrocarbon detection device (140, 240) comprises the reducing agent in the hydrocarbon detection device being exposed to a hydrophobic paper. [18] A method for detecting hydrocarbons in an aftertreatment system (100) having a reductant filter (130, 230) and a hydrocarbon detection device (140, 240) coupled to the reductant filter, the method comprising: Allowing the reducing agent in the reducing agent filter to act on the hydrocarbon detection device; and Determining that the hydrocarbon detection device has provided an indication of the presence of a hydrocarbon in the reductant in the reductant filter, wherein the hydrocarbon detection device (140, 240) is arranged on an inner surface of a side wall of the reducing agent filter (130, 230).

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