• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    A device for supplying a reducing agent includes a reforming device (A1), a obtaining section and a regulator. The reforming device (A1) mixes the fuel, which is a hydrocarbon compound, with air, and reformulates the fuel by partially oxidizing the fuel with oxygen in the air. A reformed fuel is provided in the exhaust passage (10ex) as a reducing agent. The obtaining section obtains a physical quantity as a property index. The physical amount correlates with the fuel property that is provided to the reformer (A1). The regulator sets the reforming device (A1) according to the property index obtained by the obtaining section.
    公开号:FR3016921A1
    申请号:FR1550641
    申请日:2015-01-28
    公开日:2015-07-31
    发明作者:Shigeto Yahata；Masumi Kinugawa；Yuuki Tarusawa；Keiji Noda；Mao Hosoda
    申请人:Denso Corp；
    IPC主号:
    专利说明:

    [0001] The present disclosure relates to a device for providing a reducing agent for providing a hydrocarbon compound (fuel) as a reducing agent used for reducing NOx. In general, the NOx (nitrogen oxides) contained in the exhaust gas of an internal combustion engine are purified during the reaction of NOx with a reducing agent in the presence of a reduction catalyst. For example, a patent document (JP 2009-162173 A) discloses a purification system that uses fuel (hydrocarbon compound) for combustion of an internal combustion engine as a reducing agent, and the system provides the Fuel in an exhaust passage at a position upstream of a reduction catalyst. The inventors of the present disclosure have investigated a scrubber system in which fuel mixed with air is partially oxidized with oxygen in the air to reform the fuel, and the reformed fuel is supplied to a fuel passage. exhaust as reducing agent. Depending on the configuration, a reduction performance of the reducing agent is improved, whereby a NOx scrubbing rate can be increased. However, various components of different molecular structure are mixed in a hydrocarbon-based fuel (eg, light oil) on the market, and a mixing ratio of these components is different for each of the production sectors. areas of oil sales. Therefore, the fuel property on the market is variable, and when the fuel is partially oxidized to be reformed, the reduction performance of the reformed fuel is significantly affected by the difference in fuel property before it is reformed. reform. It is an object of the present disclosure to provide a reductant delivery device that suppresses a reduction in the NOx cleaning rate due to fuel property. In one aspect of the present disclosure, a device for supplying a reducing agent is for a fuel combustion system which includes an NOx purification device having a reduction catalyst arranged in an exhaust passage for purifying the NOx contained in the exhaust gas of an internal combustion engine. The device for supplying a reducing agent provides a reducing agent in the exhaust passage at a position upstream of the reduction catalyst.
    [0002] The device for supplying a reducing agent includes a reforming device, a obtaining section and a regulator. The reforming device mixes the fuel, which is a hydrocarbon compound, with air into a mixture and reformates the fuel by partially oxidizing the fuel with oxygen in the air. Reformed fuel is provided in the exhaust passage as a reducing agent. The obtaining section obtains a physical quantity as a property index. The physical amount correlates with a fuel property that is provided to the reformer. The regulator sets the reforming device according to the property index obtained by the obtaining section.
    [0003] According to the aspect of the present disclosure, the physical quantity correlated with the property of the fuel that is supplied to the reforming device is acquired as a property index, and the operation of the reforming device is regulated according to the index of property acquired. For this reason, for example, when the fuel has the property that the fuel reduction performance after being reformed is not sufficient, the reforming device is set to improve the reduction performance by increasing a supply quantity of the fuel. reducing agent or by improving the reforming action by the reforming device. As a result, a reduction in the NOx cleaning rate due to fuel ownership can be eliminated.
    [0004] The device for supplying a reducing agent according to the present invention may comprise one or more of the following characteristics: the reforming device includes a heater that heats the mixture of fuel and air, the heater being regulated by the regulator for adjust a temperature of the mixture to a target temperature. The controller changes the target temperature according to the property index when setting the heater. The reforming device includes an ozone generator which generates ozone in the air, the ozone generator being regulated by the regulator to adjust an amount of generation of ozone to a target generation quantity, and the regulator changes the target generation amount according to the property index when setting the ozone generator. - The reforming device includes a reaction vessel having a reaction chamber, wherein the fuel is mixed with the air and is oxidized with oxygen in the air, and a fuel injector which injects the fuel into the chamber reaction, the fuel injector being regulated by the regulator to adjust a fuel injection amount in the reaction chamber to a target injection amount. The regulator changes the amount of target injection according to the property index when adjusting the fuel injector. - The obtaining section obtains an NOx scrubbing rate in the NOx scrubbing device as a property index, and the regulator sets the reformer device to increase the scrubbing rate of NOx. The obtaining section obtains the property index which correlates with a heat generating amount during a fuel oxidation reaction with oxygen, and the regulator sets the reforming device so that NOx scrubbing rate in the NOx scrubber increases as the amount of heat generation during the oxidation reaction decreases. - The reforming device includes a reaction vessel having a reaction chamber, wherein the fuel is mixed with the air and is oxidized with oxygen in the air, and a temperature sensor that detects a temperature at the inside the reaction chamber, and the regulator sets the reforming device assuming that the amount of heat generation during the oxidation reaction decreases when a sensing temperature by the temperature sensor decreases. - The fuel used for combustion of the internal combustion engine is used as the fuel to be supplied to the reforming device, the obtaining section obtains an ignition delay time in the internal combustion engine as a fuel. property index, and the regulator adjusts the reforming device such that an NOx scrubbing rate in the NOx scrubbing device increases as the ignition delay time increases. - The fuel used for the combustion of the internal combustion engine is used as the fuel to be supplied to the reforming device, the obtaining section obtains a heat generating quantity in the internal combustion engine as an index of property, and the regulator adjusts the reforming device so that a NOx scrubbing rate in the NOx scrubbing device increases as the amount of heat generation in the internal combustion engine decreases. - The device for supplying a reducing agent comprises an abnormality determiner which determines an anomaly in the reforming device or the NOx purification device when the property index has a value beyond a normal range predetermined.
    [0005] The disclosure, as well as the objects, features and additional advantages thereof, will be better understood from the following description, the appended claims and the accompanying drawings, in which: FIG. 1 is a schematic view of a providing a reducing agent applied to a combustion system; Fig. 2 is a graph illustrating simulation results of temperature changes caused by the two-step oxidation reaction under conditions different from an initial temperature; Fig. 3 is a graph illustrating simulation results of temperature changes caused by the two-step oxidation reaction under conditions different from equivalence ratio; Fig. 4 is a flowchart illustrating a switching process between ozone generation and reformed fuel generation according to the reducing agent delivery device in Fig. 1; Fig. 5 is a flowchart illustrating a process of a sub-unit. program of a reformed fuel generation control illustrated in FIG. 4; Fig. 6 is a graph illustrating the simulation results of a cold flame reaction product in a case where the fuel supplied to a reaction chamber is C1oH22; Fig. 7 is a graph illustrating the simulatid results of a cold flame reaction product in a case where the fuel supplied to a reaction chamber is C16F134; Fig. 8 is a graph illustrating the simulation results showing a total amount of the cold flame reaction product shown in Figs. 6 and 7; Fig. 9 is a flowchart illustrating a process for modifying the operation of a reforming device according to the property of the fuel; Fig. 10 is a graph illustrating a correlation between a NOx scrubbing rate and fuel property; Fig. 11 is a graph illustrating an amount of reducing agent suitable for fuel property; Fig. 12 is a graph illustrating an amount of reducing agent suitable for the NOx scrubbing rate; Fig. 13 is a chart illustrating an appropriate heater temperature for fuel property; Fig. 14 is a map illustrating an amount of ozone supply suitable for the fuel property; Fig. 15 is a graph illustrating a correlation between a heat generation amount in an internal combustion engine and the fuel property; Fig. 16 is a graph illustrating a correlation between ignition delay time in an internal combustion engine and fuel property; Fig. 17 is a graph illustrating a correlation between a temperature within the reaction chamber and the property of the fuel; Fig. 18 is a schematic representation of a device for supplying a reducing agent applied to a combustion system; Figure 19 is a schematic representation of a device for providing a reducing agent applied to a combustion system; and Fig. 20 is a schematic representation of a device for providing a reducing agent applied to a combustion system. We will now describe a plurality of embodiments of the present disclosure with reference to the drawings. In embodiments, an item that corresponds to a subject described in a previous embodiment may be assigned the same reference number, and a redundant explanation relating to that item may be omitted. When only one element of a configuration is described in one embodiment, another previous embodiment may be applied to the other elements of the configuration. The elements can be combined even if it is not explicitly described that the elements can be combined. The embodiments may be partially combined even though it is not explicitly described that the embodiments may be combined, provided that the combination is not harmful.
    [0006] First Embodiment A combustion system as illustrated in FIG. 1 includes an internal combustion engine 10, a supercharger 11, a diesel particulate filter (DPF) 14, a FPD regeneration device (regeneration COD 14a) , an NOx purification device 15, a reducing agent purification device (purification COD 16) and a device for supplying a reducing agent. The combustion system is mounted on a vehicle and the vehicle is powered by an output from the internal combustion engine 10. In the present embodiment, the internal combustion engine 10 is a compression-ignition diesel engine utilizing an internal combustion engine 10. diesel fuel (light oil) for combustion.
    [0007] The supercharger 11 includes a turbine 11a, a rotating shaft 1 lb and a compressor 11c. The turbine 1a is disposed in an exhaust passage 10ex for the internal combustion engine 10 and rotates thanks to the kinetic energy of the exhaust gas. The rotary shaft 11b connects a wheel of the turbine 11a to a wheel of the compressor 11c and transmits a rotational force of the turbine 1a to the compressor 11c. The compressor 11c is disposed in an intake passage 10in of the internal combustion engine 10 and supplies intake air to the internal combustion engine 10 after compression (i.e., overcompression) of the intake air. A cooler 12 is disposed in the intake passage 10in downstream of the compressor 11c. The cooler 12 cools the intake air compressed by the compressor 11c, and the compressed intake air cooled by the cooler 12 is distributed in a plurality of combustion chambers of the internal combustion engine 10 through a manifold. admittance once a flow quantity of the compressed intake air is adjusted by a throttle valve 13.
    [0008] The regeneration catalyst 14a (Diesel Oxidation Catalyst), the diesel particulate filter (DPF) 14, the NOx purification device 15 and the purification cell 16 are arranged in this order in the exhaust passage 10ex. downstream of the turbine 1 la. The FPD 14 collects the particles contained in the exhaust gas.
    [0009] The regeneration COD 14a includes a catalyst that oxidizes the unburned fuel contained in the exhaust gas and burns the unburned fuel. By burning the unburned fuel, the particles collected by the FPD 14 are burned and the FPD 14 is regenerated, whereby the collection capacity of the FPD 14 is maintained. It should be noted that this combustion of the unburned fuel within the regeneration COD 14a is not performed consistently but is performed provisionally when the regeneration of the FPD 14 is required. A supply passage 32 of the device for supplying a reducing agent is connected to the exhaust passage 10ex downstream of the FPD 14 and upstream of the NOx purification device 15. A reformed fuel generated by the supply device of FIG. a reducing agent is provided as a reducing agent in the exhaust passage 10ex through the feed passage 32. The reformed fuel is generated by partial oxidation of the hydrocarbon (i.e., fuel), which is used as a reducing agent, partially oxidized hydrocarbon, such as aldehyde, as we will describe later with reference to Figure 7. The NOx purification device 15 includes a nest support bee 15b for carrying a reduction catalyst and a housing 15a housing the support 15b. The NOx scrubber purifies the NOx contained in the exhaust gas by reacting the NOx with the reformed fuel in the presence of the reduction catalyst, namely, a reduction process of NOx in N2. It should be noted that although O 2 is also contained in the exhaust gas in addition to NO x, the reformed reducing agent selectively reacts (preferably) with NO x in the presence of O 2. In the present embodiment, the reduction catalyst has adsorptivity to adsorb NOx. More specifically, the reduction catalyst demonstrates that it has the adsorptivity to adsorb NOx in the exhaust gas when a catalyst temperature is below an activation temperature at which the reduction reaction by the reduction catalyst can occur. In contrast, when the temperature of the catalyst is greater than the activation temperature, the NOx adsorbed by the reduction catalyst are reduced by the reformed fuel and then released from the reduction catalyst. For example, the NOx scrubbing device can exhibit NOx adsorption performance with a silver / alumina catalyst that is carried by the support 15b. The purification COD 16 comprises a housing which houses a support carrying an oxidation catalyst. The scrubbing COD 16 oxidizes the reducing agent, which exits the NOx scrubber without being used for NOx reduction, in the presence of the oxidation catalyst. Thus, it is possible to prevent the reducing agent from being released into an atmosphere through an outlet of the exhaust passage 10ex. It should be noted that an activation temperature of the oxidation catalyst (e.g., 200 ° C) is lower than the activation temperature (e.g., 250 ° C) of the reduction catalyst. We will then describe the device for providing a reducing agent. In general, the reducing agent supplying device generates the reformed fuel and supplies the reformed fuel into the exhaust passage 10ex through the supply passage 32. The reducing agent supplying device includes a reforming device A1 and an electrical control unit (ECU 80), as will be described hereinafter. The reforming device Al includes a discharge reactor 20 (ozone generator), an air pump 20p, a reaction chamber 30, a fuel injector 40 and a heater 50. The discharge reactor 20 includes a housing 22 having a fluid passage 22a and a plurality of electrode pairs 21 are arranged within the fluid passage 22a. More specifically, the electrodes 21 are held inside the housing 22 by means of electrical insulating elements. The electrodes 21 have a flat shape and are arranged to face each other in parallel. An electrode 21, which is grounded, and the other electrode 21, to which a high voltage is applied when electric power is supplied to the discharge reactor 20, are arranged alternately. The application of energy to the electrodes 21 is controlled by a microcomputer 81 of the ECU 80. The air which is blown by the air pump 20p flows into the housing 22 of the discharge reactor 20. The pump 20p e`st air driven by an electric motor, and the electric motor is controlled by the microcomputer 81. The air blown by the air pump 20p flows into the fluid passage 22a inside the housing .22, and passes through the discharge passages 2-1a formed between the electrodes 21.
    [0010] The reaction vessel 30 is attached to a downstream side of the discharge reactor 20, and a fuel injection chamber 30a is formed inside the reaction vessel 30. In the reaction chamber 30a, fuel is mixed. to air to give a mixture and the fuel is oxidized with oxygen in the air.
    [0011] The air that has passed through the discharge passages 21a flows into the reaction chamber 30a through the air inlet 30c, and then exits an injection port 30b formed in the reaction vessel 30. The injection port 30b is in communication with the supply passage 32. The fuel injector 40 is attached to the reaction vessel 30. Fuel in liquid form (liquid fuel) within a reservoir 40t fuel is supplied to the fuel injector 40 by a pump 40p, and injected into the reaction chamber 30a through the injection ports (not shown) of the fuel injector 40. The fuel inside The fuel tank 40t is also used for combustion as described above, and thus the fuel is commonly used for the combustion of the internal combustion engine 10 and used as a reducing agent. The fuel injector 40 comprises an injection valve and the valve is actuated by an electromagnetic force by means of an electromagnetic solenoid. The microcomputer 81 controls the power supply to the electromagnetic solenoid.
    [0012] The heater 50 is attached to the reaction vessel 30, and the heater 50 includes a heating element (not shown) that generates heat when electric power is supplied to the heater. The power supply to the heating element is controlled by the microcomputer 81. A heat generating surface of the heater 50 is positioned within the reaction chamber 30a, and heats the liquid fuel injected from the heater. fuel injector 40. The liquid fuel heated by the heater 50 is vaporized inside the reaction chamber 30a. The vaporized fuel is further heated to a given or higher temperature by the heater 50. As a result, the fuel is thermally decomposed into a hydrocarbon that has a small number of carbon atoms, i.e. a cracking occurs. product. The fuel injector 40 is above the heat generating surface of the heater 50, and the liquid fuel is injected from the fuel injector 40 onto the heat generating surface. The liquid fuel adhering to the heat generating surface is vaporized. A temperature sensor 31 which detects a temperature inside the reaction chamber 30a is attached to the reaction vessel 30. Specifically, the temperature sensor 31 is arranged above the heat generating surface of the heater 50 within the reaction chamber 30a. A temperature detected by the temperature sensor 31 is a vaporized fuel temperature after reaction with air. The temperature sensor 31 generates information (detected temperature) on the detected temperature to the ECU 80.
    [0013] When the electric power is supplied to the discharge reactor 20, the electrons emitted from the electrodes 21 collide with the oxygen molecules contained in the air in the discharge passages 21a. As a result, ozone is generated from the oxygen molecules. That is, the discharge reactor 20 brings the oxygen molecules into a plasma state through a discharge process, and generates ozone as the active oxygen. Then, the ozone generated by the discharge reactor 20 is contained in the air flowing in the reaction chamber 30a. A cold flame reaction occurs in the reaction chamber 30a. In the cold flame reaction, fuel in the form of gas is partially oxidized with oxygen or ozone inside the air. Partially oxidized fuel is referred to as "reformed fuel", and partial oxide (eg, aldehyde) may be one of the examples of reformed fuel in which a portion of the fuel (hydrocarbon compound) is oxidized with an aldehyde group (CHO). It should be noted that the fuel in a high temperature environment burns by self-ignition through an oxidation reaction with the oxygen contained in the air, even in the atmospheric pressure. Such a self-igniting combustion oxidation reaction is also referred to as a "hot flame reaction" in which carbon dioxide and water are generated while generating heat. However, when a ratio of fuel and air (equivalent ratio), and the ambient temperature are within given ranges, a period during which the oxidation reaction remains in the cold flame reaction becomes longer, as described below, and then the hot flame reaction occurs. That is, the oxidation reaction occurs in two stages, the cold flame reaction and the hot flame reaction (refer to Figures 2 and 3). The cold flame reaction is expected to occur when the ambient temperature is low and the equivalent ratio is low. In the cold flame reaction, the fuel is partially oxidized with oxygen in the ambient air. When the ambient temperature increases due to heat generation caused by the cold flame reaction, and then, as a given time elapses, the partially oxidized fuel (eg, aldehyde) is oxidized, whereby the Hot flame reaction occurs. When the partially oxidized fuel, such as aldehyde, generated through the cold flame reaction is used as the NOx scrubbing agent, an NOx scrubbing rate is improved over a case. wherein fuel that is not partially oxidized is used. FIGS. 2 and 3 illustrate simulation results showing a change of a temperature (ambient temperature) of the reaction chamber 30a with respect to a time elapsed from the start of a spraying in the case where fuel (hexadecane) is sprayed on the heater 50 having a temperature of 430 ° C. In addition, FIG. 2 illustrates the simulation at the respective temperatures of the heater 50. In FIG. 2, the symbols L1, L2, L3, L4, L5 and L6 indicate the results when the heater temperature is set at 530 ° C, 430 ° C, 330 ° C, 230 ° C, 130 ° C and 30 ° C, respectively. As indicated by the symbol Li, when the heater temperature is 530 ° C, there is almost no hold period in the cold flame reaction, and the oxidation reaction is completed in one step.
    [0014] In contrast, when the heater temperature is set to 330 ° C or 430 ° C as indicated by the symbols L2 and L3, the two-step oxidation reaction occurs. In addition, when the heater temperature is set to 330 ° C, a start time of the cold flame reaction is delayed with respect to a case where the heater temperature is set to 430 ° C, as indicated by the symbols L2 and L3. Further, when the heater temperature is set to 230 ° C or lower, as indicated by the symbols LA to L6, none of the cold flame reaction and the hot flame reaction occur, i.e. oxidation does not occur.
    [0015] In the simulation illustrated in FIG. 2, the equivalent ratio, which is a ratio by weight of the fuel injected into the air supplied, is defined at 0.23. In this respect, the present inventors obtained the results illustrated in FIG. 3 with the simulation of the different equivalent ratios. It should be noted that the equivalent ratio can be defined as a value by dividing "the weight of fuel contained in an air-fuel mixture" by "the weight of fuel that can be completely burned". As illustrated in FIG. 3, when the equivalent ratio is set to 1.0, there is virtually no hold period in the cold flame reaction, and the oxidation reaction is completed in one step. Further, when the equivalent ratio is set to 0.37, the start timing of the cold flame reaction is advanced, a cold flame reaction rate increases, a cold flame reaction period decreases, and the ambient temperature at the time of completion of the cold flame reaction increases, compared to a case in which the equivalent ratio is set to 0.23. The following findings can be made from the results of Figures 2 and 3. Namely, when the ambient temperature is below a lower limit value, no oxidation result occurs. When the ambient temperature is above the lower limit value but the equivalent ratio is greater than or equal to 1.0, a single-stage oxidation reaction region in which the oxidation reaction is completed in one step is formed. When the ambient temperature is within a given temperature range, and the equivalent ratio is within a given equivalent ratio range, a two-step oxidation reaction occurs. When the ambient temperature is adjusted to an optimum temperature (e.g. 370 ° C) within the given temperature range, the equivalent ratio which allows the two-step oxidation reaction becomes a maximum value (e.g. , 1.0). Therefore, in order to generate the cold flame reaction as soon as possible, the temperature of the heater can be adjusted to the optimum temperature, and the equivalent ratio can be set to 1.0. However, since the cold flame reaction does not occur when the equivalent ratio exceeds 1.0, it is desirable to adjust the equivalent ratio to a value less than 1.0 of a given margin. In the simulation illustrated in FIGS. 2 and 3, an ozone concentration in the air is set to zero, and the start time of the cold flame reaction occurs earlier as the ozone concentration increases. The microcomputer 81 of the ECU 80 includes a memory unit for storing programs, and a central unit executing arithmetic processing according to the programs stored in the memory unit. The ECU 80 controls the operation of the internal combustion engine 10 on the basis of sensor detection values. The sensors may include an accelerator pedal sensor 91, a motor speed sensor 92, a throttle opening sensor 93, an intake air pressure sensor 94, an intake quantity sensor 10 95, an exhaust temperature sensor 96, or the like. The accelerator pedal sensor 91 detects an amount of depression of an accelerator pedal of a vehicle by a driver. The motor speed sensor 92 detects a rotational speed of an output shaft 10a of the internal combustion engine 10 (i.e., a rotational speed of the engine). The throttle opening sensor 93 detects an opening amount of the throttle valve 13. The intake air pressure sensor 94 detects a pressure of the intake passage 10in at a position downstream of the throttle valve 13. The sensor intake amount 95 detects a mass flow rate of the intake air. The ECU 80 generally controls a quantity and an injection timing of the fuel for combustion that is injected from a fuel injection valve (not shown) at a rotational speed of the output shaft 10a and a motor charge of the internal combustion engine 10. In addition, the ECU 80 controls the operation of the reforming device Al on the basis of an exhaust gas temperature detected by the exhaust gas temperature sensor. In other words, the microcomputer 81 switches between the generation of reformed fuel and the generation of ozone by repeatedly executing a process (i.e., a program) as shown in FIG. predetermined period. The process starts when an ignition switch is turned on and is run constantly when the internal combustion engine is running. In step 10 of Figure 4, the microcomputer 81 determines whether the internal combustion engine 10 is running. When the internal combustion engine 10 is not running, the operation of the device for supplying a reducing agent (reforming device) is stopped in step 15. More specifically, when electric power is supplied at the discharge reactor 20, the air pump 20p, the fuel injector 40 and the heater 50, the power supply is stopped. While when the internal combustion engine 10 is running, the reducing agent supply device operates at a temperature of the reduction catalyst (NOx catalyst temperature) within the NOx scrubber 15. More specifically, in step 11, the air pump 20p is operated with a predetermined amount of power. Then, in step 12, it is determined whether the temperature of the NOx catalyst is lower than an activation temperature Ti of the reduction catalyst (e.g., 250 ° C). The temperature of the NOx catalyst is estimated by using an exhaust gas temperature detected by the exhaust gas temperature sensor 96. It should be noted that the activation temperature of the reduction catalyst is a temperature at which the reformed fuel can purify NOx through the reduction process. When it is determined that the temperature of the NOx catalyst is lower than the activation temperature Ti, a subroutine process for an ozone generation control is performed (step 13). Initially, a predetermined amount of power is supplied to the electrodes 21 of the discharge reactor 20 to start an electric discharge. Then, the power supply to the heater 50 is stopped, and the power supply to the fuel injector 40 is stopped. According to the ozone generation control, the discharge reactor 20 generates ozone and the generated ozone is supplied in the exhaust passage 10ex through the reaction chamber 30a and the supply passage 32. case, if the feed to the heater 50 is implemented, the ozone will be heated by the heater 50 and will subside. In addition, if fuel is supplied, the ozone inside the discharge reactor 20 will react with the supplied fuel. In view of this, in the above-mentioned ozone generation control, the heating by the heater 50 and the fuel supply are stopped. For this reason, since the reaction of the ozone with the fuel and the collapse related to the heating can be avoided, the generated ozone is provided in the exhaust passage 10ex as it is.
    [0016] When it is determined that the temperature of the NOx catalyst is greater than or equal to the activation temperature T1 in Fig. 4, a reformed fuel generation control subroutine process illustrated in Fig. 14 is performed at the same time. step 14.
    [0017] We will outline the process of Figure 5 according to the dashed lines in the figure. In step 30, the operation of the heater 50 is set to adjust a temperature within the reaction vessel 30 within a given temperature range. Then, in step 40, the operation of the fuel injector 40 is controlled to inject fuel corresponding to an amount of the reducing agent that is required at the NOx scrubber 15. Next, In step 50, the operation of the air pump 20p is controlled to adjust the equivalent ratio, which is the ratio of the fuel to be supplied to the reaction vessel 30 to the air, within a given equivalent ratio range. . The temperature range and the equivalent ratio range are the ranges in the aforementioned two-step oxidation reaction regions. As a result, the cold flame reaction occurs, and thus the reformed fuel is generated. In addition, in step 60, the feed to the discharge reactor 20 is adjusted to a fuel concentration within the reaction vessel 30.
    [0018] As a result, ozone is generated, and the generated ozone is supplied to the reaction vessel 30. Thus, the start time of the cold flame reaction is advanced, and the cold flame reaction time is reduced. . As a result, even when the size of the reaction vessel is reduced so that a fuel holding time within the reaction vessel is reduced, the cold flame reaction can be completed during the holding period. whereby the size of the reaction vessel 30 can be reduced. The microcomputer 81 executing step 30 may have a "temperature regulator (regulator)". The microcomputer 81 executing step 40 may have a "fuel injection amount regulator (regulator)". The microcomputer 81 executing step 50 may have an "equivalent ratio regulator (regulator)". The microcomputer 81 executing step 60 may have a "discharge power regulator (regulator)".
    [0019] The details of steps S30, S40, S50 and S60 will be discussed below with reference to FIG. 5. We will first describe the process of step 30 performed by the temperature controller. In step 31, a temperature in the delivery device of a reducing agent, namely, a temperature inside the reaction vessel 30, is obtained. Specifically, a sensing temperature Tact detected by the temperature sensor 31 is obtained. In the following step 32, a heating amount by the heater 50 is adjusted so that the sensing temperature Tact corresponds to a target temperature Ttrg based on a difference AT between the predetermined target temperature Ttrg and the temperature of the heater. Tact detection. Specifically, a feed rate to the heater 50 is adjusted according to the difference AT. The target temperature Ttrg used in step 32 is set at room temperature (e.g., 370 ° C) at which the equivalent ratio becomes maximum in the aforementioned two-step oxidation reaction region. Since a temperature of the reaction chamber 30a increases during the cold flame reaction, a temperature of the heater 50 itself is set to be a value below the target temperature Ttrg of a temperature increase amount. during the cold flame reaction. We will then describe the process of step 40 performed by the fuel injection amount regulator. In step 41, a fuel supply value, which is necessary to reduce all the NOx flowing in the NOx scrubber 15, into the NOx scrubber without excess or defect is defined as a target fuel flow Ftrg. The target fuel flow rate Ftrg is the mass of fuel to be supplied to the NOx scrubber per unit time. Specifically, the target fuel flow rate Ftrg is defined on the basis of the NOx inflow rate that will be described hereinafter, and on the NOx catalyst temperature. The NOx inflow is the mass of NOx flowing through the NOx scrubber per unit time. For example, the NOx inflow can be estimated on the basis of an operating condition of the internal combustion engine 10. The NOx catalyst temperature is a temperature of the reduction catalyst inside the scrubber. NOx 15. For example, the temperature of the NOx catalyst can be estimated on the basis of a temperature detected by the exhaust gas temperature sensor 96. The target fuel flow rate Ftrg increases as the inflow of NOx increases. In addition, since a reduced amount (reduction performance) of NOx in the presence of the reduction catalyst changes with the temperature of the NOx catalyst, the target fuel flow rate Ftrg is set according to a difference in the reduction performance at the temperature of the NOx catalyst. For example, a map representing an optimum value of the target fuel flow Ftrg with respect to the NOx inflow and the NOx catalyst temperature is stored in the microcomputer 81 in advance. The target fuel flow rate Ftrg is defined with reference to the map based on the NOx inflow and the NOx catalyst temperature. In the following step 42, the operation of the fuel injector 40 is set to inject fuel based on the target fuel flow rate Ftrg defined in step 41. Specifically, an opening time of Fuel injector 40 increases as the target fuel flow rate Ftrg increases, thereby increasing a quantity of fuel injected during a valve opening operation. The target fuel flow rate Ftrg may correspond to the "target injection amount".
    [0020] We will then describe the process of step 50 performed by the equivalent ratio regulator. In step 51, a target 4trg equivalent ratio that provides the cold flame response corresponding to the Tact detection temperature is calculated. Specifically, a maximum value 4max of the equivalent ratio, which corresponds to the ambient temperature and which is the maximum value of the equivalent ratio in the two-step oxidation reaction region, is stored as the target equivalent ratio clitrg in the micro -computer 81 in advance. For example, a map of a value of the target equivalent ratio 4trg corresponding to the ambient temperature is prepared and the map is stored in advance. Then, the target equivalent ratio 4trg corresponding to the Tact detection temperature is calculated with reference to the card. In the following step 52, a target airflow Atrg is calculated based on the target equivalent ratio 4trg defined in step 51, and the target fuel flow Ftrg defined in step 42. Specifically, the target airflow Atrg is calculated to check at 4trg = Ftrg / Atrg. In the next step 53, the operation of the air pump 20p is set based on the target air flow Atrg calculated in step 52. Specifically, the duty cycle of excitation to the air pump 20p increases as the target airflow Atrg increases.
    [0021] We will then describe the process of step 60 performed by means of the discharge power regulator. Initially, an Otrg target ozone flow rate is calculated in step 61 on the basis of the target fuel flow rate Ftrg defined in step 41. Specifically, the Otrg target ozone flow rate is calculated so that a the ratio of an ozone concentration to a fuel concentration within the reaction chamber 30a becomes a given value (e.g., 0.2). For example, the ratio is set so that the cold flame reaction can be completed in a given time (e.g., 0.02 sec). In the following step 62, a target excitation amount Ptrg to the discharge reactor 20 is calculated on the basis of the target airflow Atrg calculated in step 52 and the target ozone flow Otrg calculated at step S61. That is, an excitation power to the discharge reactor 20 is set according to the target excitation amount Ptrg for adjusting an amount of ozone generation to a target generation amount. Specifically, since the air holding time in the discharge passages 21a decreases as the target air flow rate Atrg increases, the increase in the target excitation amount Ptrg is set higher. In addition, the amount of Ptrg target excitation increases as the Otrg target ozone rate increases. In the next step 63, the amount of excitation to the discharge reactor 20 is set based on the target excitation amount Ptrg calculated in step 62.
    [0022] Specifically, the duty cycle of excitation to the discharge reactor 20 increases as the amount of target excitation Ptrg increases. According to the process described above in FIG. 5, the microcomputer 81 controls the operation of the reforming device Al by using the target temperature Ttrg, the target fuel flow Ftrg, the target airflow Atrg and the quantity of fuel. Ptrg target excitation, like four setting parameters. However, a difference in the fuel property provided to the fuel injector 40 from the fuel tank 40t greatly affects the refueling fuel reduction performance. For this reason, an optimum value of the setting parameters also changes depending on the fuel property. Under these circumstances, in the present embodiment, the fuel property is estimated, and the adjustment parameters for adjusting the reforming device A1 may change depending on the fuel property estimation results.
    [0023] The x-axis in FIGS. 6 and 7 represents the type of reformed fuel generated through the cold flame reaction, and the number of carbon atoms contained in the reformed fuel increases in a straight direction in the figures. The ordinate axis in FIGS. 6 and 7 represents a molar fraction with which the respective reformed fuels are generated. As illustrated in the figures, the number of carbon atoms contained in the reformed fuel generated by means of the cold-flame reaction becomes important, when fuel having as property a large number of carbon atoms is provided in the chamber. 30a reaction (refer to the dashed lines in Figure 7). The reformed fuel having the largest number of carbon atoms has a low reduction performance in the presence of the NOx catalyst. In addition, as illustrated in Figure 8, the mole fraction of the reformed fuel decreases as the number of carbon atoms in the fuel increases, and thus the number of moles in the reducing agent decreases. For this reason, the microcomputer 81 controls the reforming device Al according to the process shown in FIG. 9 so that it changes the adjustment parameter so that a purification ratio increases when the number of atoms of carbon in the fuel property increases. Namely, in step 70 of Fig. 9, a physical amount correlating with fuel property is obtained as a property index.
    [0024] In the present embodiment, the NOx scrubbing rate by the NOx scrubber is obtained as a property index. The NOx purification rate is a rate of the amount of NOx reduced by the NOx purification device 15 on the amount of NOx flowing in the NOx purification device 15. The correlation esi such as the NOx is lowered when the fuel property is unsuitable for the reduction. In more detail, the NOx sensor 97 is disposed in the exhaust passage 10ex downstream of the NOx scrubber 15 and the NOx sensor 97 detects an outgoing amount of NOx that has not been reduced by the NOx. Furthermore, an incoming quantity of NOx, which escapes from the internal combustion engine 10 and flows into the NOx purification device 15, is estimated on the basis of the condition of operation of the internal combustion engine 10. Next, a rate of the outgoing amount of NOx on the incoming amount of NOx is calculated as the NOx scrubbing rate. At the next step 71, it is determined whether the property index (NOx scrubbing rate) obtained in step 70 is within a normal range. For example, when the NOx scrubbing rate is below a predefined lower limit value, the occurrence of an abnormality in the NOx scrubbing device 15 or the reforming device A1 is estimated. Then, in step 75, an abnormality indicator is activated, and the fact that the anomaly occurs is notified to the user. On the other hand, when the property index obtained in step 70 is within the normal range, the setting parameter of the reforming device A1 is changed according to the property index in the following step 72. For example, as shown in Fig. 10, the fuel property is no longer suitable for reduction when the NOx scrubbing rate is low, and the reduction performance is also low. Therefore, when the NOx scrubbing rate is low, the setting parameter is changed so that scrubbing rate increases. In the present embodiment, the target fuel flow rate Ftrg is changed as a setting parameter. That is, as illustrated in FIG. 11, the target fuel flow rate Ftrg is corrected such that an amount of the reducing agent increases when the fuel property is no longer suitable for the reduction. Specifically, a map of a target fuel flow rate correction amount Ftrg (amount of reducing agent) corresponding to the NOx scrubbing rate is prepared as illustrated in Fig. 12, and the map is stored at the same time. advanced. Then, the target fuel flow rate correction amount Ftrg corresponding to the NOx purification rate (property index) obtained in step 70 is calculated by means of the map illustrated in FIG. 12, and the target fuel flow rate. Ftrg is corrected with the amount of correction. With the above processing, the target fuel flow rate Ftrg set in step 41 of Fig. 5 is corrected, and the operation of the fuel injector 40 is set based on the corrected target fuel flow Ftrg at step 42 of Fig. 5. In step S73 of Fig. 9, the adjustment parameter that has been corrected in step 72 is learned. Specifically, the map used to calculate the target fuel flow Ftrg in step 41 of Fig. 5 is rewritten and updated. That is, an optimum value of the target fuel flow rate Ftrg with respect to the NOx inflow and the NOx catalyst temperature is rewritten at the target fuel flow rate Ftrg which is corrected in step 72. When the internal combustion engine 10 runs the next time, the ownership of the fuel is likely to be very similar to that of the present case. Therefore, the target fuel flow rate Ftrg is thus learned so that a fuel injection amount can be rapidly changed to the fuel injection amount that matches the fuel property in a subsequent operation. When it is determined in step 74 that the NOx scrubbing rate (property index) is not improved for a given time or a longer time although the adjustment parameter is corrected at step 72, the process proceeds to the above-mentioned step 75, and the fault indicator is activated. The microcomputer 81 executing step 70 may have the "obtaining section" that obtains the property index. The microcomputer 81 executing step 72 may have the "property index regulator (regulator)" which regulates the operation of the reforming device Al according to the property index. The microcomputer 81 executing step 71 may have the "anomaly determiner" that determines an abnormality in reforming device A1 or the NOx scrubbing device 15 when the property index has a value beyond 25 of a predetermined normal range. As described above, the reducing agent supplying device according to the present embodiment obtains the NOx scrubbing rate as a property index, and modifies the setting of the Al reforming device, namely, a The amount of fuel injection from the fuel injector 40 is varied depending on the rate of purification of the NOx acquired. Specifically, when the fuel that has a low property index and is not suitable for reduction is provided, the target fuel flow Ftrg (setting parameter) is corrected upward. For this reason, an amount of reducing agent provided in the exhaust passage 10ex increases, whereby a reduction in the NOx scrubbing rate due to the fuel property can be suppressed. On the other hand, when the property index is high, the target fuel flow Ftrg is corrected downwards. As a result, an excessive supply of a quantity of reducing agent in the exhaust passage 10ex is prevented. As a result, excessive or deficient supply of the reducing agent due to a difference in fuel property can be suppressed. Further, in the present embodiment, the target fuel flow rate Ftrg in the plurality of adjustment parameters for reforming device Al is changed according to the property index. For this reason, since the supply amount of the reducing agent is adjusted according to the difference of the fuel property, the amount of reducing agent which corresponds to the property of the fuel can be supplied with high precision.
    [0025] In addition, in the present embodiment, the NOx scrubbing rate is obtained as the property index, and assuming that the reduction performance of the reformed fuel generated decreases as the scrubbing rate of NOx decreases. the operation of the reforming device A1 is adjusted so that the NOx purification rate by the NOx purification device increases. Since the correlation between the NOx scrubbing rate and the fuel property is high, the difference in fuel property can be reflected in the setting of the Al reformer with high accuracy and high reaction. Further, in the present embodiment, when the scrubbing rate of NOx as a property index has a value beyond the normal range in step 71 of FIG. 9, it is determined that the An anomaly occurs in reforming device A1. When the property index exceeds the normal range, a probability that the reforming device A1 is in a state of anomaly is greater than a probability for the property of the fuel. is imprecise. For this reason, according to the present embodiment, the anomaly of reforming device A1 can be detected. In addition, in the present embodiment, the reforming device A1 includes the reaction vessel 30 in which the fuel is oxidized with oxygen in the air. A temperature inside the reaction vessel 30 and the equivalent ratio are adjusted to generate the cold flame reaction, and fuel (reformed fuel) partially oxidized through the cold flame reaction is provided in the reaction passage. 10ex exhaust as NOx reducing agent. For this reason, the NOx scrubbing rate can be improved over a case where fuel that is not partially oxidized is used as a reducing agent. Further, in the present embodiment, the discharge reactor 20 is provided, and ozone generated by the discharge reactor 20 is provided in the reaction vessel 30 when the cold flame reaction is generated. For this reason, the start time of the cold flame reaction can be advanced, and the cold flame reaction time can be reduced. As a result, even when the size of the reaction vessel is reduced, so that a fuel holding time within the reaction vessel is reduced, the cold flame reaction can be completed during the time. keeping. Thus, the size of the reaction vessel 30 can be reduced. Further, in the present embodiment, the power supply used for the electric discharge is adjusted according to the fuel concentration in the reaction chamber 30a throughout the process of step 60 of FIG. For example, the Otrg target ozone flow rate is calculated so that a ratio of the ozone concentration to the fuel concentration falls to a given value (for example 0.2), and then a discharge power is set. . For this reason, the excess or lack of the concentration of ozone with respect to the fuel concentration is suppressed, so that the start of the cold flame reaction can be advanced by providing the ozone, and the power consumption at the discharge reactor 20 can be reduced. Further, in the present embodiment, when a temperature of the reduction catalyst is lower than the activation temperature T1, the ozone generated by the discharge reactor 20 is supplied to the reaction chamber 30a while stopping the fuel injection by the fuel injector 40, thereby providing ozone in the exhaust passage 10ex. Accordingly, it is possible to prevent the reformed fuel as a reducing agent from being supplied when the reduction catalyst in the NOx purification device is not activated.
    [0026] Since the NO of the exhaust gas is oxidized to NO2 by the supply of ozone, and is adsorbed inside the NOx scrubbing catalyst, an amount of NOx adsorption to the interior The NOx scrubbing device can increase.
    [0027] In addition, the present embodiment discusses the heater 50 that heats the fuel and the temperature sensor 31 that senses a temperature (room temperature) within the reaction chamber 30a. The temperature controller in step 30 of Fig. 5 sets the operation of the heater 50 to a temperature sensed by the temperature sensor 31, thereby adjusting a temperature within the reaction chamber 30a to a given temperature range. . As a result, a temperature inside the reaction chamber 30a is detected directly by the temperature sensor 31. In addition, the fuel in the reaction chamber 30a is heated directly by the heater 50. For this reason, the adjusting a temperature within the reaction chamber 30a to the given temperature range. It should be noted that the range of the specified equivalent ratio where the cold flame reaction occurs may be different depending on a temperature inside the reaction chamber 30a. In the present embodiment taking into account the above, the ratio controller equivalent to step S50 of FIG. 5 modifies the erg equivalent target ratio according to the detection temperature Tact. For this reason, even when the detection temperature Tact is shifted from the target temperature Ttrg, since the equivalent ratio is adjusted to a real temperature in the reaction chamber 30a, the cold flame reaction can definitely occur.
    [0028] Further, in the present embodiment, the target fuel flow rate Ftrg is set in step 40 (fuel injection amount controller) of FIG. 5 based on a required flow rate of the reducing agent. which is required by the NOx scrubber 15. The target airflow Atrg is set based on the target fuel flow rate Ftrg so that the equivalent ratio falls within an equivalent ratio range given in step 50 (equivalent ratio regulator). For this reason, the equivalent ratio can be adjusted to the given equivalent ratio range while satisfying the required flow rate of the reducing agent required by the NOx scrubber 15.
    [0029] Second Embodiment In the above embodiment, the target fuel flow rate Ftrg (setting parameter) is corrected according to the fuel property so that the amount of reducing agent to be supplied in the exhaust passage 10ex changes depending on the fuel property. In contrast, in the second embodiment, the target temperature Ttrg (setting parameter) of the heater 50 is corrected according to the property of the fuel so that a temperature inside the reaction chamber 30a changes according to the property. fuel.
    [0030] Namely, as illustrated in FIG. 13, the target temperature Ttrg is corrected so that the temperature of the heater increases when the property of the fuel is no longer suitable for the reduction. For this reason, a temperature inside the reaction chamber 30a increases, and the start time of the cold flame reaction is advanced as illustrated in FIG. 2.
    [0031] Then, since an amount of fuel flowing in the exhaust passage 10ex without being oxidized by the reaction chamber 30a is reduced, a decrease in the NOx cleaning rate due to the fuel property can be suppressed. .
    [0032] Third Embodiment In the first and second embodiments, the target fuel flow rate Ftrg or the target temperature Ttrg is corrected according to the fuel property. In contrast, according to the third embodiment, the target excitation amount Ptrg (control parameter) of the discharge reactor 20 is corrected according to the property of the fuel to change the amount of ozone supply in the reaction chamber 30a according to the ownership of the fuel. Namely, as illustrated in FIG. 14, the target temperature Ttrg is corrected so that the amount of ozone supply increases when the property of the fuel is no longer suitable for the reduction. For this reason, since the reaction in the reaction chamber 30a is accelerated, a quantity of fuel flowing into the exhaust passage 10ex without being oxidized in the reaction chamber 30a can be reduced. As a result, a reduction in the NOx cleaning rate due to fuel ownership can be eliminated.
    [0033] Fourth Embodiment In the first embodiment, the NOx scrubbing rate is obtained as a property index. In contrast, according to the fourth embodiment, a heat generating amount in the combustion chambers of the internal combustion engine 10 is obtained as a property index. Specifically, a heat generating amount in a combustion cycle is estimated based on a pressure inside the combustion chambers that is detected by a cylinder pressure sensor, and a change in a value. detected from the motor speed sensor 92. As shown in Figure 15, the setting parameter is changed so that the NOx scrubbing rate increases, assuming that the fuel property is no longer suitable for the reduction. when the amount of heat generation estimated is small. Accordingly, even in the present embodiment, a decrease in NOx scrubbing rate due to fuel property can be suppressed. Further, in the present embodiment, since a heat generation amount is obtained as a property index, the property index can be obtained when a temperature of the reduction catalyst is lower than the activation temperature T1, and the NOx purification device 15 does not purify the NOx. Further, in the present embodiment, there is provided the temperature sensor 31 which senses a temperature inside the reaction chamber 30a, and the operation of the reforming device changes assuming that a generation amount of heat during an oxidation reaction (amount of reaction heat generation) decreases when the temperature of detection by the temperature sensor 31 decreases. Specifically, the setting parameter is changed so that the NOx scrubbing rate increases. According to the above configuration, since a temperature inside the reaction chamber 30a is detected directly, the property index corresponding to a heat generating amount can be obtained with high accuracy. Fifth Embodiment In the first and fourth embodiments, the NOx scrubbing rate or the heat generating amount is obtained as a property index. In contrast, according to the fifth embodiment, a firing delay time in the combustion chambers of the internal combustion engine 10 is obtained as a property index. Specifically, a time (ignition delay time) from the fuel injection into the combustion chambers until auto ignition is calculated based on a pressure change inside the chambers of combustion, which is detected by the cylinder pressure sensor. As illustrated in FIG. 16, the setting parameter is modified such that the NOx scrubbing rate increases, assuming that the fuel property is no longer suitable for the reduction when the calculated ignition delay time increases. Accordingly, even in the present embodiment, a reduction in the NOx purification rate due to fuel property can be suppressed. Further, in the present embodiment, since the ignition delay time is obtained as a property index, the property index can be obtained even when a temperature of the reduction catalyst is lower than the activation temperature Ti, and the NOx purification device 15 does not purify the NOx.
    [0034] Sixth Embodiment In the fifth embodiment, the ignition delay time is obtained as a property index. In contrast, in the present embodiment, a temperature in the reaction chamber 30a (reaction chamber temperature), i.e., the temperature of detection by the temperature sensor 31 is obtained as a property index. The reaction chamber temperature decreases as the amount of reaction heat generation as the fuel is oxidized decreases. Under these circumstances, as shown in FIG. 17, the setting parameter is modified so that the NOx scrubbing rate increases, assuming that the fuel property is no longer suitable for the reduction when the chamber temperature of reaction decreases. In addition, when the reaction chamber temperature is outside the given normal range, it is determined that reforming device A1 is abnormal. For example, when the reaction chamber temperature is greater than the normal range, a disadvantage of overheating the fuel due to heater failure 50 or excessive fuel injection due to a failure of the fuel injector. Fuel 40 is taken into account.
    [0035] Accordingly, even in the present embodiment, a decrease in NOx scrubbing rate due to fuel property can be suppressed. Further, in the present embodiment, the reaction chamber temperature is obtained as a property index, and the reaction chamber temperature has a strong correlation with the property of the fuel. Therefore, it is possible to obtain the property index with high accuracy. Seventh Embodiment In the first embodiment illustrated in FIG. 1, air is supplied to the discharge reactor 20 by the air pump 20p. In contrast, in a device for supplying a reducing agent according to the second embodiment illustrated in FIG. 15, part of the intake air in the internal combustion engine 10 is introduced into the discharge reactor 20. Specifically, a branch pipe 36h is connected between a portion of the intake passage 10in downstream of the compressor 11c and upstream of the cooler 12 and the fluid passage 22a of the discharge reactor 20. In addition, a branch pipe 36c is connected between a portion of the intake passage 10in downstream of the cooler 12 and the fluid passage 22a. High temperature inlet air that has not been cooled by cooler 12 is provided in discharge reactor 20 through branch pipe 36h. In contrast, a low temperature intake air, after being cooled by the cooler 12, is provided in the discharge reactor 20 through the branch pipe 36c. A solenoid valve 36 which opens and closes an internal passage of the respective bypass pipes 36h and 36c is attached to the branch pipes 36h and 36c. The operation of the solenoid valve 36 is controlled by the microcomputer 81.
    [0036] When the solenoid valve 36 is actuated to open the branch pipe 36h and close the branch pipe 36c, the high temperature inlet air flows into the discharge reactor 20. When the solenoid valve 36 is actuated to open the bypass pipe 36c and close the bypass pipe 36h, the low temperature intake air flows into the discharge reactor 20. The operation of the solenoid valve 36 allows switching between a mode in which the air high temperature inlet that has not been cooled by the cooler 12 is derived upstream of the cooler 12, and a mode in which the low temperature intake air after being cooled by the cooler 12 is derived in Downstream of the cooler 12. In this case, the method of supplying the low temperature intake air is selected during an ozone generation control, and the generated ozone is prevented from being destroyed by the heat of the intake air. The mode of supply of the high temperature intake air is selected in another case than the ozone generation control, and it is prevented that the fuel heated by the heater 50 is cooled by the intake air to inside the reaction chamber 30a. In addition, the opening of the solenoid valve 36 is adjusted, which makes it possible to adjust a quantity of portions of the intake air which is compressed by the supercharger 11 and must be supplied to the discharge reactor 20. of a period during which the solenoid valve 36 is open, a quantity of intake air which flows into the combustion chambers of the internal combustion engine 10 is reduced by a quantity of parts of the air of admission flowing through bypass pipes 36h and 36c. For this reason, the microcomputer 81 corrects the opening of the throttle valve 13 or a compression amount of the compressor 11c, so that a quantity of intake air flowing into the combustion chambers increases in the amount of the intake air flowing through the bypass pipes 36h and 36c during the opening period of the solenoid valve 36. As described above, a reforming device A2 according to the present embodiment includes solenoid valve 36, and the solenoid valve 36 is opened to provide a portion of the compressed air intake by the supercharger 11 into the discharge reactor 20. For this reason, air containing oxygen can be provided in the discharge reactor 20 without the air pump 20p, as illustrated in FIG. 1. Eighth embodiment The reforming device Al illustrated in FIG. 1 generates ozone by means of the discharge reactor 20, and provides the ozone generated in the reaction chamber 30a so as to accelerate the oxidation reaction of the fuel. In contrast, in a reforming apparatus A3 according to the eighth embodiment, the discharge reactor 20 is removed, and the ozone is not supplied in the reaction chamber 30a, as illustrated in FIG. even in the reforming device A3 without the discharge reactor 20, when the setting parameter is changed according to the property index, a decrease in the cleaning rate of NOx due to the fuel property can be suppressed.
    [0037] Ninth Embodiment In the reforming device A1 illustrated in FIG. 1, the discharge reactor 20 is disposed upstream of the reaction chamber 30a in the direction of the air flow. In contrast, in a reforming device A4 according to the ninth embodiment, the discharge reactor 20 is disposed downstream of the reaction chamber 30a in the direction of the air flow, as shown in FIG. the reforming device A4, the oxidation reaction occurs slightly inside the reaction chamber 30a, and the oxidation reaction occurs mainly inside the discharge passages 21a of the discharge reactor 20. the discharge passages 21a, the oxygen molecules in the air are ionized, and the fuel is oxidized in the circumstance where the ionized active oxygen atoms exist. Therefore, in the discharge reactor 20, a portion of the fuel is oxidized and the reformed fuel is generated. In this way, even in the reforming device A4 which reformulates the fuel inside the discharge reactor 20, a reduction in the NOx cleaning rate due to the fuel property can be suppressed by adjusting the adjustment parameter according to the property index. Other Embodiments Preferred embodiments of the present invention have been described above. However, the present invention is not limited to the embodiments described above, but may be implemented with various modifications as illustrated hereinafter.
    [0038] In the embodiments described above, any of the target temperature setting parameters Ttrg, the target fuel flow rate Ftrg, the target air flow rate Atrg, and the target excitation amount Ptrg are modified according to the property index. On the contrary, the different adjustment parameters can be modified according to the property index. In the embodiment illustrated in FIG. 1, the heater 50 is arranged inside the reaction vessel 30. Alternatively, the heater 50 may be arranged outside the reaction vessel 30 such that the fuel or the air is heated to a position upstream of the reaction vessel 30. In addition, in the embodiment illustrated in FIG. 1, the temperature sensor 31 is arranged inside the reaction vessel 30. the temperature sensor 31 may be arranged at a position downstream of the reaction vessel 30. In the embodiment described above as shown in FIG. 1, the fuel injector 40 is used as atomizer which atomizes the hydrocarbon in liquid form and provides the atomized hydrocarbon to the heater. A vibrating device that atomises the fuel in liquid form by vibrating the fuel can be used as an atomizer. The vibrating device may include a vibrating plate that vibrates at a high frequency and the fuel vibrates on the vibrating plate.
    [0039] In the embodiment described above illustrated in FIG. 15, the intake air is derived from two parts of the intake passage 10in upstream and downstream of the cooler 12 through the branch pipes 36h and 36c. . On the contrary, any of the two branch pipes 36h and 36c can be eliminated, and the mode switching by the solenoid valve 39 can also be eliminated.
    [0040] When the device for supplying a reducing agent is in a complete shutdown state in which the generation of both ozone and the reformed reducing agent is stopped, the electric discharge at the discharge reactor 20 can be stopped to reduce excessive energy consumption. The device for supplying a reducing agent may be in the complete shutdown state when, for example, the temperature of the NOx catalyst is below the activation temperature and the amount of adsorbed NOx reaches the saturation amount. or when the temperature of the NOx catalyst rises above a maximum temperature at which the reduction catalyst can reduce NOx. In addition, the operation of the air pump 20p can be stopped in the complete off state so as to reduce the excessive consumption of energy. In the embodiment described above as shown in FIG. 1, the reduction catalyst which physically adsorbs NOx (ie, physisorption) is used in the NOx purification device 15, but a reducing agent which adsorbs chemically NOx (ie, chemisorption) can be used. The NOx scrubber 15 can adsorb NOx when an air-fuel ratio in the internal combustion engine 10 is poorer than a stoichiometric air-fuel ratio (i.e., when the engine 10 is operating in a mixture combustion poor) and can reduce NOx when the air-fuel ratio in the internal combustion engine 10 is not poorer than the stoichiometric air-fuel ratio (ie, when the engine 10 is operating in non-lean burn combustion). In this case, the ozone is generated at the time of the lean burn and the reformed reducing agent is generated at the time of the non-lean burn. One example of a catalyst that adsorbs NOx at the time of lean burn can be a platinum and barium supported chemisorption reduction catalyst. The delivery device of a reducing agent may be applied to a combustion system which comprises the NOx purification device without the adsorption function (i.e., physisorption and chemisorption functions). In this case, in the NOx purification device 15, an iron-based or copper-based catalyst can be used as the catalyst whose NOx reduction performance is within a given temperature range of the lean burn, and a reforming substance can be supplied to these catalysts as a reducing agent. In the embodiment described above, the temperature of the NOx catalyst used in step 12 of FIG. 12 is estimated on the basis of the exhaust gas temperature detected by the exhaust gas temperature sensor. 96. However, a temperature sensor may be attached to the NOx scrubber 15, and the temperature sensor can directly detect the temperature of the NOx catalyst. Alternatively, the temperature of the NOx catalyst can be estimated based on a rotational speed of the output shaft 10a and a motor load of the internal combustion engine 10.
    [0041] In the embodiment described above as shown in FIG. 1, the discharge reactor 20 comprises the electrodes 21, each having a flat shape and facing each other in parallel. However, the discharge reactor 20 may include an acicular needle-shaped electrode (pin electrode) and an annular electrode annularly surrounding the needle electrode. In the embodiment described above as shown in Figure 1, the device for providing a reducing agent is applied to the combustion system which is installed in a vehicle. However, the active substance delivery system can be applied to a stationary combustion system. Further, in the embodiments as shown in FIG. 1, the device for supplying a reducing agent is applied to a diesel engine with self-ignition compression, and diesel for combustion is used as a reducing agent. However, the delivery device of a reducing agent can be applied to a self-igniting gasoline engine, and gasoline for combustion can also be used as a reducing agent. Means and functions provided by the ECU may be provided, for example, solely by the software, only the hardware, or a combination thereof. The ECU may consist of, for example, an analog circuit.
    权利要求:
    Claims (10)
    [0001]
    REVENDICATIONS1. Device for supplying a reducing agent for a fuel combustion system which includes an NOx scrubbing device (15) having a reduction catalyst arranged in an exhaust passage (10ex) for purifying the NOx contained in the gas exhaust system of an internal combustion engine (10), the device for supplying a reducing agent providing a reducing agent in the exhaust passage (10ex) at a position upstream of the reduction catalyst, the supply device a reducing agent comprising: a reforming device (A1, A2, A3, A4) which mixes the fuel, which is a hydrocarbon compound, with air into a mixture and reformates the fuel by partial oxidation of the fuel with oxygen in the air, a reformed fuel being provided in the exhaust passage (10ex) as a reducing agent; a obtaining section (S70) which obtains a physical quantity as a property index, the physical quantity correlating with the property of the fuel supplied to the reforming device (Al, A2, A3, A4); and a regulator (S72) which adjusts the reforming device (Al, A2, A3, A4) according to the property index obtained by the obtaining section (S70).
    [0002]
    Device for supplying a reducing agent according to claim 1, wherein the reforming device (Al, A2, A3, A4) includes a heater (50) which heats the mixture of fuel and air, the heater (50) being set by the regulator to adjust a temperature of the mixture to a target temperature, wherein the regulator changes the target temperature according to the property index when setting the heater.
    [0003]
    Device for supplying a reducing agent according to claim 1 or 2, wherein the reforming device (Al, A2, A3, A4) includes an ozone generator (20) which generates ozone in the air, the ozone generator being regulated by the regulator to adjust a generation amount of ozone to a target generation amount; and the regulator changes the target generation amount according to the property index when setting the ozone generator.
    [0004]
    A device for supplying a reducing agent according to any one of claims 1 to 3, wherein the reforming device (Al, A2, A3, A4) includes a reaction vessel (30) having a reaction chamber ( 30a), wherein the fuel is mixed with the air and is oxidized with oxygen in the air, and a fuel injector (40) which injects fuel into the reaction chamber (30a), the fuel injector fuel (40) being regulated by the regulator to adjust a fuel injection amount in the reaction chamber (30a) to a target injection amount, and the regulator modifies the target injection amount according to the property index when adjusting the fuel injector (40).
    [0005]
    5. Device for supplying a reducing agent according to any one of claims 1 to 4, wherein the obtaining section obtains an NOx purification rate in the NOx purification device as an index of property, and the regulator sets the reforming device (Al, A2, A3, A4) to increase the rate of purification of NOx.
    [0006]
    6. Device for supplying a reducing agent according to any one of claims 1 to 4, wherein the obtaining section obtains the property index which correlates with a quantity of heat generation during a reaction. oxidation of the fuel with oxygen, and the regulator adjusts the reforming device (A1, A2, A3, A4) so that a NOx purification rate in the NOx purification device increases when the amount of heat generation during the oxidation reaction decreases.
    [0007]
    A device for supplying a reducing agent according to claim 6, wherein the reforming device (Al, A2, A3, A4) includes a reaction vessel (30) having a reaction chamber (30a), wherein the fuel is mixed with the air and is oxidized with oxygen in the air, anda temperature sensor (31) which detects a temperature inside the reaction chamber (30a), and the regulator sets the reforming (Al, A2, A3, A4) assuming that the amount of heat generation during the oxidation reaction decreases when a sensing temperature by the temperature sensor decreases.
    [0008]
    A reducing agent supplying device according to any one of claims 1 to 4, wherein the fuel used for the combustion of the internal combustion engine is used as the fuel to be supplied to the reformer ( A1, A2, A3, A4), the obtaining section obtains an ignition delay time in the internal combustion engine (10) as a property index, and the regulator sets the reforming device (Al, A2, A3, A4) such that an NOx scrubbing rate in the NOx scrubbing device increases as the ignition delay time increases.
    [0009]
    A reducing agent supplying device according to any one of claims 1 to 4, wherein the fuel used for the combustion of the internal combustion engine is used as the fuel to be supplied to the reforming device ( A1, A2, A3, A4), the obtaining section obtains a heat generating amount in the internal combustion engine (10) as a property index, and the regulator sets the reforming device (A1, A2 , A3, A4) such that an NOx scrubbing rate in the NOx scrubbing device increases as the amount of heat generation in the internal combustion engine (10) decreases.
    [0010]
    A device for providing a reducing agent according to any of claims 1 to 9, further comprising: an abnormality determiner (S71) which determines an abnormality in the reforming device (Al, A2, A3, A4) or the NOx scrubbing device when the property index has a value beyond a predetermined normal range.
    类似技术:
    公开号 | 公开日 | 专利标题
    US9556775B2|2017-01-31|Reducing agent supplying device
    FR3016921A1|2015-07-31|
    FR2852446A1|2004-09-17|INTERNAL COMBUSTION ENGINE WITH A FUEL CELL IN AN EXHAUST SYSTEM
    JP6323239B2|2018-05-16|Reducing agent addition device
    FR3016920A1|2015-07-31|
    JP2005155422A|2005-06-16|Catalyst control device for internal combustion engine
    US20130236364A1|2013-09-12|Exhaust purifying apparatus in internal combustion engine
    FR2831923A1|2003-05-09|System and process for the purification of exhaust gases from internal combustion engines, particularly for the elimination of particulate contamination from diesel engines
    WO2011151560A1|2011-12-08|Internal combustion engine supplied with fuel and equipped with a low-pressure exhaust gas recirculation circuit and with an additional system for producing hydrogen
    FR2982639A1|2013-05-17|EXHAUST GAS CONTROL APPARATUS FOR INTERNAL COMBUSTION ENGINE
    WO2010139875A1|2010-12-09|Internal combustion engine
    JP6455377B2|2019-01-23|Reducing agent addition device
    JP6515481B2|2019-05-22|Ozone supply device
    JP6083373B2|2017-02-22|Highly active substance addition equipment
    JP2010059833A|2010-03-18|Exhaust emission control device
    EP1757353A1|2007-02-28|Oxidation process for purifying combustion engine exhaust gas and system for supporting the performance of an oxidation catalyst
    FR2948412A1|2011-01-28|Exhaust line for diesel engine of motor vehicle, has fuel introducing device comprising fuel vaporizer equipped with vaporizing chamber, and heating unit partially located inside vaporizing chamber to vaporize liquid fuel
    FR3069889B1|2019-08-09|EXHAUST LINE COMPRISING A THREE-WAY CATALYST AND A PETROL PARTICLE FILTER
    FR2943095A1|2010-09-17|Particle filter regeneration process for internal combustion diesel engine of motor vehicle, involves regenerating particle filter by injecting fuel into exhaust line based on defined injection parameter i.e. temperature set point
    FR3069278B1|2019-08-02|METHOD FOR DETERMINING THE PASSAGE OF THE ROSSE POINT AT THE EXIT OF A DEPOLLUTION MEMBER
    JP2010014060A|2010-01-21|Control device for internal combustion engine
    JP6461585B2|2019-01-30|Exhaust purification device
    FR3073254A1|2019-05-10|VEHICLE CONTROL DEVICE
    WO2011010069A1|2011-01-27|Reforming method, and energy conversion machine including reforming device
    FR2936010A1|2010-03-19|Exhaust line for diesel engine of vehicle, has branch line including connection arranged in upstream of diesel injecting system and another connection arranged in downstream of nitrogen oxide trap
    同族专利:
    公开号 | 公开日
    DE102015100205A1|2015-07-30|
    US20150211402A1|2015-07-30|
    JP6015685B2|2016-10-26|
    CN104819037A|2015-08-05|
    US9605575B2|2017-03-28|
    FR3016921B1|2019-01-25|
    JP2015140793A|2015-08-03|
    CN104819037B|2019-02-12|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    JP3531489B2|1998-08-05|2004-05-31|三菱ふそうトラック・バス株式会社|NOx reduction system for flue gas|
    WO2003048536A1|2001-12-03|2003-06-12|Catalytica Energy Systems, Inc.|System and methods for improved emission control of internal combustion engines|
    US6832473B2|2002-11-21|2004-12-21|Delphi Technologies, Inc.|Method and system for regenerating NOx adsorbers and/or particulate filters|
    JP4367065B2|2003-09-19|2009-11-18|トヨタ自動車株式会社|Exhaust gas purification device for internal combustion engine|
    JP4320582B2|2003-10-24|2009-08-26|トヨタ自動車株式会社|Exhaust gas purification device for internal combustion engine|
    JP4507885B2|2005-01-14|2010-07-21|トヨタ自動車株式会社|Exhaust gas purification device for internal combustion engine|
    US7093429B1|2005-06-01|2006-08-22|Gm Global Technology Operations Inc.|Reforming diesel fuel for NOx reduction|
    JP2007177663A|2005-12-27|2007-07-12|Toyota Motor Corp|Exhaust emission control system for internal combustion engine|
    US8069654B2|2007-01-16|2011-12-06|Eaton Corporation|Optimized rhodium usage in LNT SCR system|
    JP4803186B2|2008-01-09|2011-10-26|トヨタ自動車株式会社|Fuel reformer|
    US8099951B2|2008-11-24|2012-01-24|GM Global Technology Operations LLC|Dual bed catalyst system for NOx reduction in lean-burn engine exhaust|
    JP2011149388A|2010-01-25|2011-08-04|Honda Motor Co Ltd|Exhaust emission control system|
    EP2754866A4|2011-09-05|2015-04-22|Hino Motors Ltd|Exhaust gas purification apparatus|US9556845B2|2013-03-12|2017-01-31|Ecomotors, Inc.|Enhanced engine performance with fuel temperature control|
    JP6459908B2|2015-11-03|2019-01-30|株式会社デンソー|Exhaust purification system and purification control device|
    CN109653853B|2019-01-28|2020-12-18|江苏大学|Diesel engine tail gas combined treatment system and control method|
    法律状态:
    2016-01-21| PLFP| Fee payment|Year of fee payment: 2 |
    2017-01-20| PLFP| Fee payment|Year of fee payment: 3 |
    2018-01-19| PLFP| Fee payment|Year of fee payment: 4 |
    2018-03-30| PLSC| Search report ready|Effective date: 20180330 |
    2019-01-23| PLFP| Fee payment|Year of fee payment: 5 |
    2020-10-16| ST| Notification of lapse|Effective date: 20200910 |
    优先权:
    申请号 | 申请日 | 专利标题
    JP2014015934A|JP6015685B2|2014-01-30|2014-01-30|Reducing agent addition device|
    JP201415934|2014-01-30|
    [返回顶部]