A device for storing a first liquid intended to heat a second liquid.

Abstract

A device for storing a first liquid for heating a second liquid. The invention relates to a device (5) comprising a first volume (10) for storing a first liquid, in particular a coolant from a vehicle drive system, in particular a motor vehicle, the device (5) comprising a second volume (20) for storing a second liquid, in particular a second liquid used in a selective catalytic reduction system in the exhaust line of an internal combustion engine drive system, in particular a second liquid of the urea type or containing urea, so as to heat and / or maintain at temperature and / or warm such a second liquid by heat transfer from such a first liquid. Illustration: Fig. 2

Description

Title of the invention: Device for storing a first liquid intended to heat a second liquid. Technical field of the invention

[0001] The invention relates to a device comprising a first volume intended to store a first liquid and a second volume intended to store a second liquid, the first liquid being intended to heat the second liquid. The invention also relates to a system comprising such a device. The invention also relates to a vehicle comprising such a system or such a device. State of the prior art

[0002] An industrial vehicle comprising an internal combustion engine, in particular of the heavy goods vehicle type, generally comprises a means for selective catalytic reduction of nitrogen oxides NOx (known by the English abbreviation SCR for Selective Catalyst Reduction). Such a means ensures depollution at the exhaust system level by injecting urea into it. Such a vehicle then comprises a urea storage tank and a urea distribution and injection circuit. Because urea freezes and / or crystallizes at an outside temperature of the order of minus 11 degrees Celsius, such a tank and / or such a urea distribution circuit generally comprises heating means to compensate for such a phase change of the urea. Generally, a resistor or a layer, supplied with electrical energy, is installed at the urea tank and / or the distribution and injection circuit.However, when the outside temperature is negative, and even more so when the engine is cold, several minutes are necessary before urea can be injected into the exhaust system. Thus, during the first few minutes after starting the vehicle in cold weather, the treatment of nitrogen oxides is not optimal or even does not work.

[0003] Due to more stringent pollution control standards for passenger car type motor vehicles, such vehicles now need to be equipped with a selective catalytic reduction means. The absence of optimal operation of the selective catalytic reduction means during the first minutes after starting, in particular in cold weather, is not acceptable with regard to such standards. Presentation of the invention

[0004] The aim of the invention is to provide a device which overcomes the above drawbacks. In particular, the invention proposes a solution which makes it possible to maintain a reserve of urea in the liquid state for a long period after the engine has been switched off, the urea in the liquid state then being able to be used as soon as the engine is restarted, and thus to avoid the consumption of electrical energy for heating urea in cold weather. Summary of the invention

[0005] To achieve this objective, the invention relates to a device comprising a first volume intended to store a first liquid, in particular a coolant for a drive means of a vehicle, in particular a motor vehicle, the device comprising a second volume intended to store a second liquid, in particular a second liquid used in a selective catalytic reduction means at the level of an exhaust line of a drive means of the internal combustion engine type, in particular a second liquid of the urea type or comprising urea, so as to heat and / or maintain at temperature and / or reheat such a second liquid by heat transfer from such a first liquid.

[0006] The first volume and the second volume can be independent.

[0007] The device may comprise an inner wall, the inner wall being able to be arranged between the first volume and the second volume so as to transfer heat from such a first liquid to such a second liquid by thermal conduction at the inner wall.

[0008] The inner wall may comprise a conduit shape which at least partially defines the second volume, in particular a conduit shape of cylindrical section, the conduit being able to extend, or being able to extend substantially, or being able to extend at least in part, into the first volume.

[0009] The internal wall may have a small thickness, in particular between 0.8 mm and 1.5 mm, and / or the internal wall may be made of a material having high thermal conductivity, in particular aluminum or aluminum alloy.

[0010] The device may be single-piece.

[0011] The device may comprise an insulated external wall, in particular covered with thermal insulation or comprising thermal insulation.

[0012] The invention also relates to a system comprising a device as defined previously, the system comprising: - a means for injecting a second liquid of urea type or comprising urea into a selective catalytic reduction means at the level of an exhaust line of a drive means of the internal combustion engine type, the injection means being connected to the second storage volume of the device, - a cooling circuit of such a drive means of a vehicle, in particular a motor vehicle, comprising a first liquid of the coolant type circulating within the cooling circuit, the circuit of cooling comprising the first storage volume of the device, such that the first liquid within the cooling circuit heats and / or maintains at temperature and / or heats the second liquid present within the second volume of the device.

[0013] The system may include a second liquid reservoir connected to the second volume of the device such that the capacity of the second volume is a buffer reserve of the second liquid.

[0014] The invention also relates to a vehicle, in particular a motor vehicle, comprising a system as defined previously, or a device as defined previously. Presentation of figures

[0015] These objects, characteristics and advantages of the present invention will be explained in detail in the following description of an embodiment of a device given without limitation in relation to the attached figures among which:

[0016] [Fig-1] [Fig.l] is a schematic view of a motor vehicle according to a mode of realization.

[0017] [Fig.2] [Fig.2] is a schematic perspective view of a device according to a embodiment.

[0018] [Fig.3] [Fig.3] is a perspective view of the device according to the method of realization.

[0019] [Fig.4] [Fig.4] is a front view of the device according to the embodiment.

[0020] [Fig.5] [Fig.5] is a schematic view of an arrangement comprising the device according to one embodiment. Detailed description

[0021] As illustrated in [Fig.l], the vehicle 1 comprises a system 6 which will be described later. The vehicle 1 is preferably a motor vehicle, for example a city car or saloon type vehicle. Alternatively, the vehicle 1 is a commercial motor vehicle, for example a van, or an industrial vehicle, for example a heavy goods vehicle.

[0022] Preferably, the vehicle 1 comprises a means 2 for driving the vehicle.

[0023] Advantageously, the drive means 2 is a heat engine of the internal combustion engine type. The engine then preferably comprises an exhaust line 3. Preferably, the vehicle or the engine also comprises a selective catalytic reduction means 9 (SCR in English abbreviations).

[0024] The vehicle 1 comprises a device 5.

[0025] More precisely, as illustrated in [Fig.2], the device 5 comprises a first volume 10. The first volume 10 is intended to store a first liquid LL Preferably, the first liquid L1 is a coolant of the drive means 2 of the vehicle.

[0026] The device 5 further comprises a second volume 20. The second volume 20 is intended to store a second liquid L2. Preferably, the second liquid is used in the selective catalytic reduction means 9, preferably at the exhaust line 3 of the engine. Advantageously, the second liquid L2 is urea or comprises urea.

[0027] As will be explained below, the first volume and / or the second volume is arranged so as to heat and / or maintain at temperature and / or reheat the second liquid by heat transfer from the first liquid.

[0028] Advantageously, the first volume 10 and the second volume 20 are independent. Preferably, the device 5 comprises an internal wall 15. The internal wall 15 is arranged between the first volume 10 and the second volume 20. In this case, the transfer of heat from the first liquid to the second liquid is ensured by thermal conduction at the level of the internal wall 15. Preferably, the internal wall 15 extends around the second volume 20.

[0029] Advantageously, as illustrated in [Fig. 2], the inner wall 15 comprises a conduit shape which at least partially defines the second volume 20. For example, the inner wall 15 has a conduit shape, for example of cylindrical or substantially cylindrical section. For example, the conduit extends, or extends substantially, or extends at least partly into the first volume 10.

[0030] Preferably, the internal wall 15 has a small thickness, for example between 0.8 mm and 1.5 mm. In addition or alternatively, the internal wall 15 is made of a material having high thermal conductivity, preferably aluminum whose thermal conductivity is approximately 229 W / mK at 20°C.

[0031] For example, the device 5 is a single-piece unit. For example, the device 5 is molded.

[0032] Preferably, the device 5 comprises an external wall 30. Advantageously, the external wall 30 is insulated. For example, the insulation is obtained by covering the external wall 30 with a thermal insulator. Alternatively, the external wall 30 comprises a thermal insulator. For example, as illustrated in Figures 3 and 4, the external wall 30 comprises two parts or shells 31, 32. For example, the two shells 31, 32 are fixed to each other by means of a fixing means, in particular clips 33. For example, an external seal is inserted between the two shells so as to obtain the sealing of the first volume 10 with respect to the external environment and an internal seal is inserted between the two shells so as to obtain the sealing of the second volume 20 with respect to the first volume 10.

[0033] Preferably, the first volume 10 comprises an inlet and an outlet 11, 12 for the first liquid L1 (coolant of the engine 2) and the second volume 20 comprises an inlet and an outlet 21, 22 for the second liquid L2 (urea).

[0034] Preferably, the internal wall 15 is distant from the external wall 30 so that the first liquid L1 completely, or substantially completely, covers the internal wall 15 when the first volume is full or substantially full of first liquid.

[0035] For example, the first volume has a capacity equal, or substantially equal, to the second volume. Alternatively, the second volume has a capacity greater than the capacity of the first volume. Preferably, the capacity of the first volume is greater than the capacity of the second volume so as to promote the heating, or at least the maintenance at temperature, of the second liquid by transfer of heat from the first liquid.

[0036] More precisely, the system 6 comprises the device 5. The system 6 also comprises a means 7 for injecting the second liquid into the selective catalytic reduction means 9 and / or at the exhaust line 3 of the drive means 2. As a reminder, the drive means is preferably an internal combustion engine, for example a diesel cycle. The injection means 7 is connected to the second storage volume 20 of the device 5. The system 6 also comprises a cooling circuit 8 for the drive means 2 of the vehicle 1.

[0037] The cooling circuit 8 comprises, or is filled with, first liquid, preferably of the cooling liquid type. Preferably, the cooling liquid circulates within the cooling circuit 8, for example by means of a pump generally called a water pump (not shown). Preferably, the cooling circuit 8 comprises the first storage volume 10 of the device 5. The first volume 10 is arranged so that the first liquid present or circulating within the cooling circuit 8 heats and / or maintains at temperature and / or heats the second liquid present within the second volume 20 of the device 5.

[0038] Preferably, as illustrated in [Fig.5], the system also comprises a reservoir or reserve 4 of second liquid. The reservoir 4 is connected to the second volume 20 of the device 5 by a conduit or pipe or tubing or line 23. Thus, thanks to the presence of this reservoir 4, the capacity of the second volume 20 within the device 5 is only a buffer capacity of urea.

[0039] An exemplary arrangement 50, illustrated in [Fig. 5], comprises the internal combustion engine 2. An engine exchanger 51, preferably water or coolant / engine oil, is arranged within the cooling circuit 8 of the internal combustion engine 2. Preferably, a radiator 52 is arranged within the cooling circuit 8 so as to ensure the cooling of the coolant by exchange with air. For example, a branch of the circuit 8 comprises a thermostat 53 allowing the evacuation of the coolant reaching a predetermined high temperature. This evacuation of the coolant takes place in a high temperature part 54 of the cooling circuit 8. For example, this part 54 comprises a high temperature radiator 55 and an expansion tank 56. The arrangement 50 further comprises a secondary circuit 40 for the second liquid. The secondary circuit 40 preferably comprises a pump 41 capable of pumping the second liquid from the second volume 20 of the device 5 so as to supply the urea injection means 7 and / or the catalytic reduction means 9.

[0040] Thus, as illustrated in [Fig.5], the device 5 is installed both in the cooling circuit 8 of the engine 2 and in the secondary urea circuit 40.

[0041] More precisely, during operation of the engine (for example when the vehicle 1 comprising the engine 2 is running), the coolant circulating in the circuit 8 is heated, in particular at the water / oil exchanger 51. When the coolant reaches a target high temperature, the thermostat 53 opens to allow the coolant to pass into the high-temperature part 54 of the circuit 8 so as to lower the temperature of the coolant. This drop in temperature of the coolant is ensured by the high-temperature radiator 55.

[0042] Preferably, the coolant only circulates when the heat engine 2 is operating.

[0043] For example, the circulation of the coolant within the circuit 8 is not triggered when the engine is started. In this case, the circulation of the coolant is triggered only after a threshold value of the coolant is reached so as to promote a rapid rise in its temperature. In any case, rapid heating of the coolant is sought so that the engine 2 quickly rises to its optimum operating temperature. Alternatively, the circulation of the coolant in the circuit 8 takes place as soon as the engine is started, in particular by the actuation of a pump 57. The circulation of the coolant causes it to circulate within the first volume 10, which has the effect of immediately increasing the temperature of the device and in particular of the internal wall 15. The urea present in the second volume 20 is then heated immediately, in particular by thermal conduction.Preferably the second volume 20 is constantly, or substantially constantly, filled with urea via a supply from the tank 4 as the second volume 20 is emptied.

[0044] When the heat engine 2 is stopped, the coolant remains at temperature. Thanks to the insulated external wall 30, the coolant present in the first volume 10 of the device 5 remains at temperature for a long period. As a result, the urea present in the second volume 20 recovers at least partially the heat from the coolant which surrounds it or substantially surrounds it. When the engine is subsequently started, for example after a dozen hours, and in cold weather conditions of the order of minus 15 degrees Celsius for example, the urea has not crystallized. Indeed, during such a period without the engine being in operation, the coolant has transmitted heat to the urea, the first volume filled or substantially filled with coolant having also made it possible to isolate the urea present in the second volume from the outside cold.As a reminder, preferably, the second volume 20 is at least partially surrounded by the first volume 10. Thus, during the next start-up, the catalytic reduction means is operational from the first moments, without requiring the urea to be heated. Indeed, the urea injected into the catalytic reduction means comes directly, or substantially directly, from the second volume 20.

[0045] In other words, in the illustrated embodiment, the device 5 is a hot water storage jar (cooling liquid) shared with a urea circuit.

[0046] Thanks to the solution, the regulatory requirements requiring the reduction of NOx pollutant emissions, particularly in cold environments down to minus 2 degrees Celsius or even minus 7 degrees Celsius, are met. Indeed, the injection of urea is possible as soon as the engine is restarted, even in very cold outside temperatures. This is possible because the urea has been stored "warm" in the second volume 20 isolated from the outside environment by the internal wall 15 and especially by the first volume 10 containing the hot coolant. The solution allows the injection of urea in the engine start-up phase without having to resort to heating or reheating which also impacts CO2 emissions.This avoids crystallization or freezing or phase change of the urea which makes it impossible to inject it at cold outside temperatures, without resorting to an electrical heating method using a layer or other means in the urea tank.

[0047] Thanks to the solution, the regulatory requirements relating to the temperature rise phases of the heat engine are also satisfied. Indeed, the insulation of the device 5, in particular of its external wall 30, offers a reduction in the temperature rise time when restarting the engine via the use of the coolant stored in the first volume 10, the liquid not having completely cooled. In addition, the urea of ​​the second volume 20 contributes to maintaining at the temperature of the coolant over time without the engine running, the urea being hotter than the external environment. Thus, the device 5 makes it possible to store coolant from the engine 2 and to store it "warm" in the first volume 10 until the next starting phase of the engine 2. In addition, the rapid rise in temperature of the engine makes it possible to increase the recycling rate of exhaust gases (EGR system in particular) as well as the speed of activation of such reuse. The rapid rise in temperature of the engine also allows a rapid rise in temperature of the oil.

[0048] The solution is compact and facilitates the introduction of selective catalytic reduction, or SCR, on a motor vehicle, in particular on a private vehicle with little space, particularly in its engine compartment.

[0049] Preferably, the device 5 is designed and / or sized and / or insulated to keep the coolant hot, the temperature of the liquid during engine operation being, for example, of the order of 90 to 110 degrees Celsius.

[0050] Preferably, the device 5 is designed and / or sized and / or insulated to maintain the coolant and / or the urea at temperature, for a duration equivalent to one night, for example for 10 to 12 hours.

[0051] Preferably, the device 5 is designed and / or sized and / or insulated so as to be able to restore the liquids to temperature during the cold start phases. This results in a reduction in pollutant emissions and the possibility of injecting urea into very cold environments without the need to wait for the urea to thaw. This eliminates the need for activating electrical consumers (resistors, layers) for several minutes, which is highly penalizing for compliance with regulatory standards.

[0052] For example, the level of insulation of the device 5 of the multi-fluid storage tank type is adapted according to the ambient conditions in which the vehicle is intended to circulate, its location within the vehicle, the fluid restitution temperature and the desired restitution duration.

[0053] In summary, the solution makes it possible to share the coolant storage tank with the urea circuit in order to reduce pollutant emissions.

[0054] As mentioned above, preferably, the device 5 makes it possible to isolate the two fluids, in particular via two independent circuits. For example, the device 5 preferably makes it possible for the temperature of the urea to remain below a temperature value of the order of 65 to 70 degrees Celsius. Below this range of values, it is thus possible to avoid altering and degrading the operation of the catalytic reduction means 9 and / or the injection means 7. In this case, the device preferably allows a maximum coolant temperature of 90 to 110 degrees Celsius in the case of integration into the engine cooling circuit, or from 55 to 75 degrees Celsius if integrated into a low temperature loop of the cooling circuit.

[0055] Preferably, the distribution of the volumes 10, 20 is a function of the requirements in terms of urea volume and the space available within the vehicle. The volumes of the two fluids, provided that they are isolated from one another, are for example distributed indifferently in the device 5 according to the installation problems on the vehicle and the accessibility for the connection of the pipes or conduits or lines concerning the urea and concerning the coolant.

[0056] Thus, the calories from the coolant (preferably low temperature) are recovered to heat a buffer quantity of urea in the second volume 20 of the device 5. The buffer volume is separated from the urea injection module which comprises a larger volume of urea, in particular via the tank 4. Thus the buffer volume 20 depends on the desired activation time, the engine parameters, the area of ​​use of the vehicle or even the evolution of the legislation in terms of pollution control. For example, the total volume of urea in such a vehicle is for example between 10 liters and 30 liters. However, in view of future regulatory requirements, the total volume of urea could increase.

[0057] Generally speaking, the device 5 is adapted to the vehicle for which it is intended, in particular to the engine compartment of this vehicle.

[0058] Advantageously, as illustrated in [Fig.l], the injection means 7 allows urea injection as close as possible to the engine (for example at the exhaust manifold) and injection on the exhaust line 3 under the body. Alternatively, a single urea injection point can be envisaged. Alternatively, three or even more urea injection points can be envisaged.

[0059] Since the solution offers a saving of electrical energy, this energy can be used for other functions such as for example heating the seats or the steering wheel.

[0060] Alternatively, the coolant storage container is directly integrated into the urea tank. This results in a simplification of implementation on the vehicle due to the absence of an additional and specific pump for urea, a gain in terms of space or even a simpler urea circuit. The circulation of the urea in this case is ensured by a pump of a module comprising a pump gauge such as it is known as a module integrated into a fuel tank.

[0061] As a remark, the solution therefore achieves the desired objective of satisfying pollution control standards from the start of the engine and has the following advantages: - another fluid for heating the urea can be used, for example engine oil; - it can be used on other vehicles equipped with a thermal engine, in particular industrial vehicles, construction machinery, agricultural machinery.

Claims

Claims

1. Device (5) comprising a first volume (10) for storing a first liquid of the engine oil type of a drive means (2) of a vehicle, in particular a motor vehicle (1), characterized in that the device (5) comprises a second volume (20) for storing a second liquid used in a selective catalytic reduction means at an exhaust line (3) of a drive means (2) of the internal combustion engine type, in particular a second liquid of the urea type or comprising urea, so as to heat and / or maintain at temperature and / or reheat such a second liquid by heat transfer from such a first liquid.

2. Device (5) according to the preceding claim, characterized in that the first volume (10) and the second volume (20) are independent.

3. Device (5) according to one of the preceding claims, characterized in that the device (5) comprises an internal wall (15), the internal wall (15) being arranged between the first volume (10) and the second volume (20) so as to transfer heat from such a first liquid to such a second liquid by thermal conduction at the internal wall (15).

4. Device (5) according to the preceding claim, characterized in that the internal wall (15) comprises a conduit shape which at least partially defines the second volume (20), in particular a conduit shape of cylindrical section, the conduit extending, or extending substantially, or extending at least in part, into the first volume (10).

5. Device (5) according to one of claims 3 or 4, characterized in that the internal wall (15) has a small thickness, in particular between 0.8 mm and 1.5 mm, and / or in that the internal wall (15) is made of a material having high thermal conductivity, in particular aluminum or aluminum alloy.

6. Device (5) according to one of the preceding claims, characterized in that the device (5) is in one piece.

7. Device (5) according to one of the preceding claims, characterized in that the device (5) comprises an insulated external wall (30), in particular covered with thermal insulation or comprising thermal insulation.

8. System (6) comprising a device (5) according to one of the preceding claims, characterized in that the system (6) comprises: - a means (7) for injecting a second liquid of urea type or comprising urea into a selective catalytic reduction means (9) at the level of an exhaust line (3) of a drive means (2) of the internal combustion engine type, the injection means (7) being connected to the second storage volume (20) of the device (5), the first liquid of the engine oil type of such a drive means (2) of a vehicle heating and / or maintaining at temperature and / or heating the second liquid present within the second volume (20) of the device (5).

9. System (6) according to the preceding claim, characterized in that it comprises a reservoir (4) of second liquid connected to the second volume (20) of the device (5) so that the capacity of the second volume (20) is a buffer reserve of the second liquid.

10. Vehicle, in particular motor vehicle (1), characterized in that it comprises a system (6) according to one of claims 8 or 9, or a device (5) according to one of claims 1 to 7.

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