METHOD FOR EVALUATING ON A TEST BENCH A SOLUTION FOR IMPREGNATING A PARTICLE FILTER INTENDED FOR A MOTOR VEHICLE WITH A COMBUSTION ENGINE

Abstract

The invention relates to a method for evaluating on a test bench an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine, the test bench comprising a particulate filter sample comprising the impregnation solution, a reaction mixture and a heating system, said reaction mixture having a predetermined hourly volume reaction rate, characterized in that the method comprises the following steps: an evaluation step under starting conditions (E1) during which the sample passes from an initial temperature to a final temperature at a predetermined heating rate, said final temperature being higher than said initial temperature and an evaluation step under running conditions (E2) during which the sample is studied at a fixed temperature. Abstract figure: Fig. 1

Description

Title of the invention: METHOD FOR EVALUATING ON A TEST BENCH A SOLUTION FOR IMPREGNATING A PARTICLE FILTER INTENDED FOR A MOTOR VEHICLE WITH A COMBUSTION ENGINE

[0001] The invention relates to particulate filters for motor vehicles with thermal engines, and more particularly to the impregnation solutions present on these particulate filters.

[0002] Known from the prior art is a patent application FR3029968 which describes a device for post-treatment of exhaust gases from a combustion engine. The device comprises a set of components arranged from upstream to downstream according to the following configuration: an oxidation catalyst member, a mouth of a means for introducing a reducing agent or precursor of a reducing agent for the selective catalytic reduction of nitrogen oxides, a catalyst member for selective catalytic reduction of nitrogen oxides, a particulate filter, an ammonia leak treatment member and a catalyst member for selective catalytic reduction of nitrogen oxides. The introduction means is an injector comprising an actuator. The catalyst member for selective catalytic reduction of nitrogen oxides has a length of between 45 mm and 80 mm. The objective of the invention is to improve the performance of a pollution control system for a motor vehicle with a thermal engine.The particulate filter contains a catalytic impregnation solution for selective reduction of nitrogen oxides, which also allows for the filtration of soot. However, to evaluate the impregnation solution, it is necessary to carry out a test on the motor vehicle. In the event of poor performance or even no performance, it is necessary to completely dismantle the particulate filter to replace the impregnation solution.

[0003] The objective of the present invention is to remedy these drawbacks by proposing a means for testing an impregnation solution before its integration into the particle filter of a motor vehicle with a thermal engine.

[0004] To achieve this objective, the invention proposes a method for evaluating on a test bench an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine, the test bench comprising a sample of particulate filter comprising the impregnation solution, a reaction mixture and a heating system, said reaction mixture comprising a quantity of dioxygen, a quantity of carbon dioxide, a quantity of carbon monoxide, a quantity of dihydrogen, a quantity of nitrogen oxides, a quantity of toluene and a quantity of water, the reaction mixture being supplemented with a quantity of nitrogen, said reaction mixture having a predetermined hourly volume reaction rate, remarkable in that the method comprises the following steps: - a step of evaluating the impregnation solution under the starting conditions of said vehicle during which the sample passes from an initial temperature to a final temperature at a predetermined heating rate, said final temperature being higher than said initial temperature; - a step of evaluating the impregnation solution under the rolling conditions of said vehicle during which the sample is studied at a fixed temperature.

[0005] Thanks to the invention, the impregnation solutions are tested directly on a sample on a test bench, without this requiring the assembly of said particulate filter in said vehicle.

[0006] Advantageously, said sample has a diameter of 2.5 cm and a length greater than or equal to 2.5 cm.

[0007] Preferably, during the evaluation step under the starting conditions of said vehicle, the initial temperature is between 15°C and 25°C and the final temperature is greater than or equal to 500°C.

[0008] These are the standard conditions for reproducing vehicle startup.

[0009] Preferably, during the evaluation step in the starting conditions of said vehicle, the predetermined speed is between 1°C / s and 1°C / min.

[0010] Advantageously, the hourly volume reaction rate is between 30,000 h 1 and 150,000 h *, preferably 100,000 h 1.

[0011] Advantageously, during the evaluation step under the running conditions of said vehicle, the fixed temperature is between 400°C and 500°C, preferably 450°C.

[0012] When driving, the particle filter of a vehicle operates in this temperature range. This allows the impregnation solution to be evaluated according to real conditions.

[0013] Advantageously, the reaction mixture has a total volume, the amount of oxygen being between 0% and 2.5% by volume relative to the total volume, the amount of carbon dioxide being between 5% and 15% by volume relative to the total volume, the amount of carbon monoxide being between 0% and 4% by volume relative to the total volume, the amount of hydrogen being between 0% and 2% by volume relative to the total volume, the amount of nitrogen oxides being between 0% and 0.5% by volume relative to the total volume, the amount of toluene being between 0.005% and 0.3% by volume relative to the total volume and the amount of water is between 0% and 15% by volume relative to the total volume.

[0014] Advantageously, during the evaluation step in the rolling conditions of said vehicle, the amount of oxygen is less than 2% by volume compared to the total volume.

[0015] The invention also relates to a test bench configured to evaluate a solution for impregnating a particle filter intended for a motor vehicle with a thermal engine, remarkable in that said test bench implements said method of evaluation on a test bench of a solution for impregnating a particle filter intended for a motor vehicle with a thermal engine described above.

[0016] Furthermore, the invention relates to a motor vehicle with a thermal engine comprising a particulate filter, remarkable in that said particulate filter comprises an impregnation solution having been evaluated by implementing said evaluation method on a test bench of an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine previously described.

[0017] The invention will be further detailed by the description of a non-limiting embodiment, and on the basis of the appended figure illustrating the invention, in which [Fig.l] schematically illustrates a method of evaluating on a test bench an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine according to an embodiment of the invention.

[0018] [Fig.l] schematically illustrates a method for evaluating on a test bench an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine. The particulate filter is a device designed to reduce the emissions of harmful particles from the thermal engine. The role of the particulate filter is to permanently capture the primary soot particles from the thermal engine. However, under certain conditions such as starting for example, secondary particles, otherwise known as secondary organic aerosols, form downstream of the particulate filter. The test bench comprises a particulate filter sample. Preferably, the sample has a diameter of 2.5 cm and a length greater than or equal to 2.5 cm. The particulate filter sample comprises the impregnation solution.The purpose of the impregnation solution is to improve the retention of solid particles by the particulate filter. The test bench contains a reaction mixture for testing the impregnation solution. The reaction mixture is a combination of chemicals, or reactants, that react together to form other chemicals, or products. The reaction mixture includes a quantity of oxygen, a quantity of carbon dioxide, a quantity of carbon monoxide, a quantity of hydrogen, a quantity of nitrogen oxides, a quantity of toluene, a quantity of water, and a quantity of nitrogen. Toluene is a monocyclic aromatic component found in combustion engine emissions. For the purposes of evaluating the impregnation solution, toluene represents the precursors of organic aerosols. secondary. Thus, the evaluation serves to determine whether the impregnation solution is capable of capturing and destroying toluene, which would imply that the said impregnation solution tested is capable of capturing and destroying secondary organic aerosol precursors under real conditions. The reaction mixture has a predetermined hourly volume reaction rate. The hourly volume rate is the ratio between a volume flow rate value of the reaction mixture and a volume value of a catalyst that treats them. The hourly volume rate is thus expressed in units of volume of reactant per hour. The hourly volume rate therefore changes according to the volume flow rate value of the reaction mixture and / or the volume value of the catalyst. The catalyst is a chemical substance that accelerates the transformation of reactants into products, without changing the final result of the reaction.Advantageously, the hourly volumetric velocity is between 30,000 h 1 and 150,000 h 1, preferably 100,000 h 1. In addition, the test bench comprises a heating system. The starting and running phases of said vehicle when the heat engine has not reached an adequate temperature are the phases generating the most solid particles. The method comprises a step of evaluating the impregnation solution under the starting conditions E1 of said vehicle. During said step of evaluating the impregnation solution under the starting conditions E1, the sample undergoes a temperature increase causing it to pass from an initial temperature to a final temperature at a determined heating rate, said final temperature being higher than said final temperature. Preferably, the initial temperature is between 15°C and 25°C and the final temperature is greater than or equal to 500°C.When said motor vehicle with a thermal engine starts, the particulate filter undergoes a temperature increase. The objective of said step of evaluating the impregnation solution under the starting conditions of said vehicle is to reproduce the starting conditions. Thus, the impregnation solution can be tested without having to mount said particulate filter on said vehicle, which takes considerable time. In addition, this avoids having to test the particulate filter on a roller bench which is an expensive piece of equipment intended to carry out tests and evaluations on the vehicle. Preferably, during said step of evaluating under the starting conditions of said vehicle, the predetermined speed is between l°C / s and l°C / min. During a step of evaluating the impregnation solution under the rolling conditions E2, the sample is studied at a fixed temperature throughout the reaction.Preferably, the fixed temperature is between 400°C and 500°C, preferably 450°C. The purpose of said step of evaluating the impregnation solution under the rolling conditions E2 is to subject the sample to the temperature at which the emissions of solid particles are emitted when the vehicle is rolling and said thermal engine of the vehicle has not. still reaches the appropriate temperature. Advantageously, the reaction mixture has a total volume. The amount of oxygen is between 0% and 2.5% by volume relative to the total volume, the amount of carbon dioxide is between 5% and 15% by volume relative to the total volume, the amount of carbon monoxide is between 0% and 4% by volume relative to the total volume, the amount of hydrogen is between 0% and 2% by volume relative to the total volume, the amount of nitrogen oxides is between 0% and 0.5% by volume relative to the total volume, the amount of toluene is between 0.005% and 0.3% by volume relative to the total volume and the amount of water is between 0% and 15% by volume relative to the total volume. The amount of nitrogen is added in order to complete said reaction mixture. The percentage by volume relative to the total volume is otherwise called the volume percentage.The volume percentage makes it possible to express the volume composition of a gaseous or liquid mixture. Preferably, during said step of evaluating the impregnation solution under the E2 rolling conditions, the amount of oxygen is less than 2% by volume relative to the total volume. The invention also relates to a test bench configured to evaluate an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine, said test bench allowing the implementation of said method previously described. Furthermore, the invention relates to a motor vehicle with a thermal engine comprising a particulate filter comprising an impregnation solution having been evaluated by implementing said method previously described.

Claims

Claims

1. Method for evaluating on a test bench an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine, the test bench comprising a sample of particulate filter comprising the impregnation solution, a reaction mixture and a heating system, said reaction mixture comprising a quantity of dioxygen, a quantity of carbon dioxide, a quantity of carbon monoxide, a quantity of dihydrogen, a quantity of nitrogen oxides, a quantity of toluene and a quantity of water, the reaction mixture being supplemented with a quantity of dinitrogen, said reaction mixture having a predetermined hourly volume reaction rate,characterized in that the method comprises the following steps: - a step of evaluating the impregnation solution under the starting conditions (El) of said vehicle during which the sample passes from an initial temperature to a final temperature at a predetermined heating rate, said final temperature being higher than said initial temperature; - a step of evaluating the impregnation solution under the running conditions (E2) of said vehicle during which the sample is studied at a fixed temperature.,

2. Method according to claim 1 characterized in that said sample has a diameter of 2.5 cm and a length greater than or equal to 2.5 cm.

3. Method according to claim 1 or 2 characterized in that, during the evaluation step in the starting conditions of said vehicle, the initial temperature is between 15°C and 25°C and the final temperature is greater than or equal to 500°C.

4. Method according to any one of claims 1 to 3 characterized in that, during the evaluation step in the starting conditions of said vehicle, the predetermined speed is between 1°C / s and 1°C / min.

5. Method according to any one of claims 1 to 4, characterized in that the hourly volume reaction rate is between 30,000 h 1 and 150,000 h *, preferably 100,000 h 1.

6. Method according to any one of claims 1 to 5 characterized in that, during the evaluation step in the rolling conditions of said vehicle, the fixed temperature is between 400°C and 500°C, preferably 450°C.

7. Process according to any one of claims 1 to 6, characterized in that the reaction mixture has a total volume, the quantity of oxygen being between 0% and 2.5% by volume relative to the total volume, the quantity of carbon dioxide being between 5% and 15% by volume relative to the total volume, the quantity of carbon monoxide being between 0% and 4% by volume relative to the total volume, the quantity of hydrogen being between 0% and 2% by volume relative to the total volume, the quantity of nitrogen oxides being between 0% and 0.5% by volume relative to the total volume, the quantity of toluene being between 0.005% and 0.3% by volume relative to the total volume and the quantity of water being between 0% and 15% by volume relative to the total volume.

8. Method according to claim 7 characterized in that, during the evaluation step under the running conditions of said vehicle, the quantity of oxygen is less than 2% by volume relative to the total volume.

9. Test bench configured to evaluate an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine, characterized in that said test bench implements said method of evaluation on a test bench of an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine according to any one of claims 1 to 8.

10. Motor vehicle with a thermal engine comprising a particulate filter, characterized in that said particulate filter comprises an impregnation solution having been evaluated by implementing said evaluation method on a test bench of an impregnation solution for a particulate filter intended for a motor vehicle with a thermal engine according to any one of claims 1 to 8.

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