JP2013024521A - Burner device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a catalyst from deteriorating as catalyst combustion becomes too active to exceed a use assumption temperature of a catalyst.SOLUTION: A burner device 200 is arranged before a diesel oxidation catalyst 130 oxidizing exhaust gas in an exhaust path 110 of a diesel engine 100, and includes a burner catalyst 214 which accelerates oxidation of fuel, a combustion fuel supply part 216 which supplies the fuel to the burner catalyst, and a cooling pipe 222 in which a cooling material cooling the burner catalyst circulates.

Description

  The present invention relates to a burner device that raises the temperature of exhaust gas from a diesel engine by burning fuel.

  In recent years, a particulate filter (DPF: Diesel Particulate Filter) that removes particulate matter (PM: Particulate Matter) such as soot contained in exhaust gas of a diesel engine has become widespread. When particulate matter accumulates on this particulate filter, clogging occurs. In that case, it is necessary to perform a filter regeneration process in which the exhaust gas is heated to burn the deposited particulate matter. Therefore, a diesel oxidation catalyst (DOC) that burns fuel and raises the temperature of exhaust gas is provided in front of the particulate filter in the exhaust path.

  However, the diesel oxidation catalyst cannot raise the exhaust gas while the temperature of the exhaust gas is low and the activation temperature that promotes oxidation is not reached, such as when the engine is started or when the load is low, and the particulate filter in the subsequent stage The filter regeneration process cannot be performed. Therefore, a technique for quickly warming the diesel oxidation catalyst is desired. As a means for warming the catalyst, for example, a catalyst combustion apparatus has been proposed in which when the catalyst layer is preheated, the heat limit of the catalyst layer is not exceeded by reducing the combustion of the preheating burner (for example, Patent Document 1). ).

JP-A-7-55110

  For example, when a diesel oxidation catalyst is heated by a burner flame, there is a possibility that the exhaust gas flow rate is high or the oxygen concentration of the exhaust gas is low, resulting in misfire. Therefore, the inventor of the present application diverts the exhaust gas to suppress the flow rate, burns fuel with a burner catalyst that is a catalyst disposed in the exhaust gas with the suppressed flow rate, and converts the heated exhaust gas to a diesel oxidation catalyst. We are considering a configuration that can be discharged to

  However, in the burner catalyst, if the catalyst combustion becomes intense, the expected use temperature of the catalyst is exceeded, and the burner catalyst may be agglomerated and deteriorated. In this case, for example, even if the technique described in Patent Document 1 is used for the burner catalyst and heating by the flame of the preheating burner for preheating the burner catalyst is suppressed, the temperature rise due to catalytic combustion of the burner catalyst itself cannot be suppressed.

  In view of such a problem, an object of the present invention is to provide a burner apparatus capable of preventing deterioration of the catalyst due to exceeding the expected use temperature of the catalyst.

  In order to solve the above-mentioned problem, a burner device of the present invention, which is disposed in front of a diesel oxidation catalyst that oxidizes exhaust gas in an exhaust path of a diesel engine, includes a burner catalyst that promotes fuel oxidation, and a fuel for the burner catalyst. And a cooling pipe in which a coolant for cooling the burner catalyst circulates.

  The burner device includes a temperature detection unit that detects the temperature of the burner catalyst, and a cooling control unit that starts circulation of the coolant when the detected temperature of the burner catalyst exceeds a predetermined value. Further, it may be provided.

  In order to solve the above-mentioned problem, another burner device of the present invention, which is disposed in front of a diesel oxidation catalyst that oxidizes exhaust gas in an exhaust path of a diesel engine, includes a burner catalyst that promotes fuel oxidation, and a burner catalyst. And a cooling control unit for controlling the fuel supplied by the combustion fuel supply unit to an amount exceeding an equivalence ratio of 1.

  The burner device further includes a temperature detection unit that detects the temperature of the burner catalyst, and the cooling control unit is an amount by which the equivalent ratio becomes 1 or less when the detected temperature of the burner catalyst is equal to or less than a predetermined value. If the fuel is supplied to the combustion fuel supply unit and exceeds a predetermined value, an amount of fuel whose equivalence ratio is greater than 1 may be supplied to the combustion fuel supply unit.

  In order to solve the above-mentioned problem, another burner device of the present invention, which is disposed in front of a diesel oxidation catalyst that oxidizes exhaust gas in an exhaust path of a diesel engine, includes a burner catalyst that promotes fuel oxidation, and a burner catalyst. And a heat dissipating section for dissipating heat generated in the burner catalyst to the exhaust gas passing through the exhaust path.

  The burner catalyst may have a hole penetrating in the fuel flow direction.

  The burner catalyst may have a structure in which one or a plurality of catalyst layers in which a substrate is coated with a catalyst and one or a plurality of non-catalyst layers made of a substrate that is not coated with a catalyst are laminated.

  The burner device is provided with an inflow path through which exhaust gas diverted from the exhaust path flows, and a burner catalyst, which burns a mixture of exhaust gas and fuel and discharges the exhaust gas after combustion to the exhaust path And a combustion flow rate limiting mechanism for limiting the flow rate of the exhaust gas flowing into the combustion chamber from the inflow passage.

  According to the burner device of the present invention, it is possible to prevent deterioration of the catalyst due to exceeding the expected use temperature of the catalyst.

It is explanatory drawing for demonstrating the exhaust structure of a diesel engine. It is explanatory drawing for demonstrating the structure of the burner apparatus in 1st Embodiment. It is explanatory drawing for demonstrating the structure of the burner apparatus in 1st Embodiment. It is explanatory drawing for demonstrating the cooling structure of the burner apparatus in 1st Embodiment. It is explanatory drawing for demonstrating the structure of the burner apparatus in 2nd Embodiment. It is explanatory drawing for demonstrating the cooling structure of the burner apparatus in 2nd Embodiment. It is explanatory drawing for demonstrating the relationship between an equivalence ratio and the temperature of a burner catalyst. It is explanatory drawing for demonstrating the modification of the structure of a burner catalyst.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  FIG. 1 is an explanatory diagram for explaining an exhaust structure of the diesel engine 100. As shown in FIG. 1 (a), a diesel engine 100 compresses air in a cylinder by a piston to increase the temperature and pressure, and fuel such as light oil and heavy oil stored in a fuel tank 102 is supplied to a fuel pump 104 and an injection pump. This is a reciprocating engine that is pressurized at 106 and injected to cause an explosion and convert the energy generated by the explosion into power. The supercharger 108 is a device that improves the engine output by rotating the turbine with the energy of the exhaust gas of the diesel engine 100 and compressing the intake air to increase the intake pressure.

  The exhaust path 110 is formed by a pipe 112 for exhausting the exhaust gas discharged from the diesel engine 100 to the outside. One end of the pipe 112 is connected to the exhaust port of the diesel engine 100 and the other end is a diesel oxidation catalyst. 130. The particulate filter 120 is composed of a ceramic or metal filter that collects and removes particulate matter such as soot contained in the exhaust gas of the diesel engine 100 through, for example, holes of about 10 microns. As shown in the sectional view of FIG. 1B, the filter 120a of the particulate filter 120 causes clogging 124 when the particulate matter 122 is excessively deposited. The clogging 124 causes an increase in exhaust pressure, leading to deterioration in fuel consumption and output.

  The diesel oxidation catalyst 130 is provided between the diesel engine 100 and the particulate filter 120, and is composed of, for example, a catalyst such as platinum or palladium. The diesel oxidation catalyst 130 uses oxygen contained in the exhaust gas of the diesel engine 100 to remove unburned fuel. The temperature of the exhaust gas is raised by catalytic combustion. The heated exhaust gas flows into the particulate filter 120 at the subsequent stage, burns the particulate matter 122 deposited on the particulate filter 120, exhausts it as carbon dioxide, and eliminates clogging of the particulate filter 120 (filter regeneration processing). ).

  Such filter regeneration processing is batch processing that is executed when the particulate filter 120 is clogged, for example, until the clogging is eliminated. However, the diesel oxidation catalyst 130 cannot increase the temperature of the exhaust gas while the temperature of the exhaust gas is low and has not reached the activation temperature at which oxidation is promoted, such as when the diesel engine 100 is started or when the load is low. The filter regeneration process cannot be performed in the particulate filter 120. Therefore, the inventor of the present application diverts the exhaust gas in the exhaust passage 110 to suppress the flow velocity, burns the fuel with the burner device 200 including the catalyst disposed in the exhaust gas with the suppressed flow velocity, and raises the temperature of the exhaust gas. A configuration for assisting the temperature increase of the diesel oxidation catalyst 130 by returning the gas to the exhaust path 110 is being studied.

  However, in the catalyst of the burner device 200, if the catalyst combustion becomes intense, the expected use temperature of the catalyst is exceeded, and the catalyst may be agglomerated and deteriorated. Therefore, in the following embodiments, the burner apparatuses 200 and 300 capable of preventing deterioration due to exceeding the assumed use temperature of the catalyst will be described in detail.

(First embodiment)
2 and 3 are explanatory views for explaining the structure of the burner device 200 according to the first embodiment. As shown in FIG. 2, the burner device 200 includes an inflow path 210, a combustion chamber 212, a burner catalyst 214, a combustion fuel supply unit 216, a partition member 218, a flame heating unit 220, a cooling pipe 222, A temperature detection unit 224 and a cooling control unit 226 are provided.

  Exhaust gas (Exhausted Gas: indicated by Exh.Gas in the figure) branched from the exhaust path 110 flows into the inflow path 210 about 20% of the flow rate of the exhaust gas flowing through the exhaust path 110. The combustion chamber 212 is an area for combusting a mixture of exhaust gas and fuel from the inflow passage 210, and includes partition members 218 and 260, an outer wall 228 that forms the outer shape of the burner device 200, and an outer periphery of the pipe 112. It is surrounded by an opening 230 corresponding to the surface.

  The burner catalyst 214 is composed of a base material (not shown) and a catalyst coding material such as platinum or palladium that covers the base material, and is provided in the combustion chamber 212 to promote combustion of the air-fuel mixture. . Here, in order to further promote catalytic combustion, the burner catalyst 214 is doubled, but it may be single or triple or more. The combustion fuel supply unit 216 includes, for example, a fuel injection device (injector), sprays fuel into the combustion chamber 212 in a mist state, and supplies the fuel to the burner catalyst 214.

  The partition member 218 functions as a combustion flow rate limiting mechanism together with the hole 218a. The combustion flow rate limiting mechanism separates the inflow path 210 and the combustion chamber 212 and sets the flow rate flowing into the combustion chamber 212 from the inflow path 210, for example, about 80% of the flow rate of exhaust gas flowing through the inflow path 210, that is, the exhaust path 110. It is limited to about 16% of the flow rate of the exhaust gas flowing through. Specifically, the combustion flow rate limiting mechanism has a hole 218a (see the XX cross-sectional view of FIG. 3A), and the flow rate of the exhaust gas flowing into the combustion chamber 212 from the inflow path 210 through this hole 218a. By limiting, the flow rate of the exhaust gas in the combustion chamber 212 is suppressed.

  With such a configuration that suppresses the flow velocity, catalytic combustion by the burner catalyst 214 is stabilized. Therefore, the burner catalyst 214 can start catalytic combustion even with an exhaust gas having a low temperature and a low oxygen concentration, compared to a case where a configuration for suppressing the flow rate is not taken. In addition, the burner device 200 of the present embodiment further includes a flame heating unit 220 in order to quickly start catalytic combustion.

  The flame heating unit 220 heats the burner catalyst 214 with a flame or high-temperature exhaust gas. The flame heating unit 220 includes a flame generation chamber 250, a flame fuel supply unit 252, an ignition unit 254, a fuel holding unit 256, partition members 258 and 260, and a baffle plate 262.

  The flame generation chamber 250 is an area for generating a flame for heating the burner catalyst 214, and is surrounded by partition members 258 and 260 that are flame flow restriction mechanisms and an outer wall 228. The flame fuel supply unit 252 includes, for example, a fuel injection device, and supplies fuel to the flame generation chamber 250. The ignition unit 254 is composed of a glow plug that ignites a mixture of fuel (when liquid fuel is used, fuel in which the liquid fuel is vaporized by the heat of the ignition unit 254) and exhaust gas by heating to a temperature equal to or higher than the ignition temperature. Yes. The fuel holding unit 256 is formed of, for example, a wire mesh, sintered metal, metal fiber, glass cloth, ceramic porous body, ceramic fiber, pumice, and the like, is installed at the tip of the ignition unit 254, and is supplied from the flame fuel supply unit 252. Hold the fuel temporarily until it burns.

  The partition member 258 separates the inflow path 210 and the flame generation chamber 250, and the partition member 260 separates the flame generation chamber 250 and the combustion chamber 212. And the partition members 258 and 260 function as a flame flow restriction mechanism based on the holes 258a and 260a provided respectively. The flame flow rate limiting mechanism limits either or both of the inflow rate to the flame generation chamber 250 and the outflow rate from the flame generation chamber 250. For example, the flame flow rate limiting mechanism limits the flow rate flowing into the flame generation chamber 250 to about 20% of the flow rate of exhaust gas flowing through the inflow passage 210, that is, about 4% of the flow rate of exhaust gas flowing through the exhaust path 110.

  Specifically, the flame flow restriction mechanism allows the exhaust gas to be vented from the inflow path 210 to the flame generation chamber 250 through the hole 258a (see the YY sectional view of FIG. 3B), and combusts from the flame generation chamber 250 through the hole 260a. The exhaust gas after combustion can be ventilated into the chamber 212, and the flow rate into the flame generation chamber 250 and the flow rate out of the flame generation chamber 250 are restricted through the holes 258a and 260a, so that the inside of the flame generation chamber 250 The exhaust gas flow rate is suppressed.

  The baffle plate 262 is disposed so as to prevent a flow path that directly collides with the ignition part 254 of the exhaust gas flowing in from the inflow path 210. With such a configuration, the flow rate of the exhaust gas and the air-fuel mixture in the vicinity of the ignition part 254 can be suppressed, and the ignitability is improved.

  Subsequently, the flow of exhaust gas in the burner apparatus 200 will be described. The exhaust gas branched into the inflow path 210 flows into the combustion chamber 212 and the flame generation chamber 250. In the flame generation chamber 250, the ignition unit 254 is heated to an ignition temperature or higher, ignites and burns an air-fuel mixture, and generates a flame.

  Exhaust gas after combustion in the flame generation chamber 250 passes through the holes 260 a and flows into the combustion chamber 212 to heat the burner catalyst 214. The flame generated in the flame generation chamber 250 also heats the burner catalyst 214 through the holes 260a. When the burner catalyst 214 is heated to the activation temperature or higher, the air-fuel mixture in which the fuel supplied from the combustion fuel supply unit 216 and the exhaust gas flowing in from the holes 218a are mixed is catalytically combusted. Then, the high-temperature exhaust gas after combustion (indicated as “Heated Exh. Gas” in the figure) flows into the exhaust path 110 and raises the temperature of the exhaust gas passing through the exhaust path 110.

  As described above, the burner device 200 of the present embodiment includes the flame flow restriction mechanism and the combustion flow restriction mechanism, so that the exhaust gas is not generated in the flame generation chamber 250 or the combustion chamber 212 even when the diesel engine 100 is rotating at high speed. Since the flow rate is suppressed and the ignitability and flame holding performance can be improved, the burner catalyst 214 can be heated to stabilize catalytic combustion. Therefore, the temperature of the exhaust gas in the exhaust passage 110 can be raised by the high-temperature exhaust gas flowing out from the combustion chamber 212, and the subsequent diesel oxidation catalyst 130 can be raised to the activation temperature quickly and reliably.

  Further, for example, when the oxygen concentration of the exhaust gas is low, if a mechanism for supplying oxygen to replenish oxygen is provided, oxygen must be supplied at a pressure higher than the pressure in the exhaust passage 110, which greatly reduces the cost. It will take. However, since the burner apparatus 200 is stable in catalytic combustion by suppressing the flow rate of the air-fuel mixture, it is not necessary to provide a mechanism for supplying oxygen even when the oxygen concentration of the exhaust gas is low. Cost can be reduced.

  The burner catalyst 214 becomes higher than the expected use temperature of the catalyst due to heat generated by catalytic combustion, and if the operation in such a high temperature range continues, the burner catalyst 214 may be deteriorated. Therefore, the burner device 200 of this embodiment includes a cooling pipe 222.

  A cooling material for cooling the burner catalyst 214 circulates in the cooling pipe 222. FIG. 4 is an explanatory diagram for explaining a cooling structure of the burner device 200 according to the first embodiment. As shown in FIG. 4, the burner catalyst 214 is supplied with fuel and low-temperature exhaust gas, and the heated high-temperature exhaust gas is released. In addition, a cooling pipe 222 is passed through the burner catalyst 214 in the present embodiment, and the heat of the burner catalyst 214 is connected to the cooling pipe 222, for example, using a coolant circulating inside the cooling pipe 222 as a medium (not shown). Heat is released from the radiator to the outside air.

  Thus, since the burner apparatus 200 of this embodiment is provided with the cooling pipe 222, the burner catalyst 214 is maintained at the expected use temperature by an appropriate amount of coolant, so that even if catalytic combustion is promoted, the filter can be stably filtered. Reproduction processing can be performed.

  The temperature detector 224 detects the temperature of the burner catalyst 214. When the detected temperature of the burner catalyst 214 exceeds a predetermined value, the cooling control unit 226 starts circulation of the coolant.

  With the configuration including the temperature detection unit 224 and the cooling control unit 226, the burner apparatus 200 cools the burner catalyst 214 only when the temperature of the burner catalyst 214 rises too much, and without deteriorating the activity of the catalyst by cooling. It is possible to efficiently raise the temperature of the exhaust gas and to prevent deterioration of the catalyst.

(Second Embodiment)
In the embodiment described above, the burner apparatus 200 having the configuration in which the cooling pipe 222 cools the burner catalyst 214 has been described. Next, the burner apparatus 300 that cools the burner catalyst 214 with a configuration different from that of the cooling pipe 222 will be described in detail.

  FIG. 5 is an explanatory diagram for explaining the structure of the burner device 300 in the second embodiment, and FIG. 6 is an explanatory diagram for explaining the cooling structure of the burner device 300 in the second embodiment. . The burner device 300 includes an inflow path 210, a combustion chamber 212, a burner catalyst 214, a combustion fuel supply unit 216, a partition member 218, a flame heating unit 220, a temperature detection unit 224, a cooling control unit 326, And a heat dissipating part 328. The inflow passage 210, the combustion chamber 212, the burner catalyst 214, the combustion fuel supply unit 216, the partition member 218, the flame heating unit 220, and the temperature detection unit 224, which have already been described as the components in the first embodiment, substantially function. Therefore, the redundant description is omitted. Here, the cooling control unit 326 and the heat radiation unit 328 having different configurations will be mainly described.

  The cooling control unit 326 controls the fuel supplied from the combustion fuel supply unit 216 to an amount exceeding the equivalence ratio 1.

  FIG. 7 is an explanatory diagram for explaining the relationship between the equivalence ratio and the temperature of the burner catalyst 214. In FIG. 7, the relationship between the equivalence ratio and the temperature of the burner catalyst 214 when the oxygen supply amount is not changed is shown by a curve 290, and the relationship between the equivalence ratio and the fuel flow rate is shown by a straight line 292.

  As shown in FIG. 7, the temperature of the burner catalyst 214 increases as the fuel flow rate increases at a fuel flow rate where the equivalence ratio is 1 or less (the fuel is in a lean state). When the equivalence ratio becomes 1, the temperature of the burner catalyst 214 rises to about 1000 degrees. However, at a fuel flow rate where the equivalence ratio exceeds 1 (the fuel is in a rich state), the temperature of the burner catalyst 214 decreases as the fuel flow rate increases, and is about 700 to 800 degrees (an example of 800 degrees is shown in FIG. 7). Calm down. This is because when the combustion fuel supply unit 216 supplies an amount of fuel exceeding the equivalence ratio 1, the fuel that cannot be burned due to lack of oxygen contacts the burner catalyst 214 and vaporizes to remove the heat of vaporization, as shown in FIG. This is because it becomes unburned fuel gas and flows out into the exhaust passage 110 without generating combustion heat.

  For this reason, the cooling control unit 326 controls the fuel supplied from the combustion fuel supply unit 216 to an amount exceeding the equivalence ratio 1, so that the burner catalyst 214 is maintained at the assumed use temperature and is hardly deteriorated and stably regenerates the filter. Processing can be performed. Furthermore, since the diesel oxidation catalyst 130 disposed in the latter stage oxidizes unburned fuel gas that has not been burned by the burner device 300, the exhaust gas is further heated to be used for filter regeneration processing, so that there is no waste of fuel. The unburned fuel gas is not discharged into the outside air.

  In addition, the cooling control unit 326, particularly when the temperature of the burner catalyst 214 detected by the temperature detection unit 224 is equal to or lower than a predetermined value, supplies an amount of fuel with an equivalence ratio of 1 or less to the combustion fuel supply unit 216. When the predetermined value is exceeded, an amount of fuel whose equivalence ratio is greater than 1 is supplied to the combustion fuel supply unit 216.

  As described above, the configuration in which the fuel supply amount is changed in accordance with the temperature of the burner catalyst 214 allows the burner device 300 to supply fuel only in a situation where the burner catalyst 214 is likely to exceed the expected use temperature. Fuel consumption efficiency can be improved while preventing catalyst deterioration.

  The heat dissipating part 328 is made of, for example, a metal fin, and is disposed so that one end thereof is in contact with the burner catalyst 214 and the other end protrudes into the exhaust path 110. The heat dissipating unit 328 transfers the heat of the burner catalyst 214 transmitted from the contact portion to the exhaust path 110 side by heat conduction, and dissipates heat to the exhaust gas that passes through the exhaust path 110 and collides with the heat dissipating unit 328.

  Since the burner apparatus 300 of the present embodiment includes the heat dissipating unit 328, the burner catalyst 214 is maintained at the assumed use temperature and hardly deteriorates, and the filter regeneration process can be performed stably. Furthermore, the heat of the burner catalyst 214 is easily transferred to the exhaust gas through the heat radiating section 328, and the temperature of the exhaust gas can be increased efficiently.

  FIG. 8 is an explanatory diagram for describing a modification of the structure of the burner catalyst 214. As shown in FIG. 8A, the burner catalyst 214 (indicated by 214a, 214b, and 214c in FIG. 8A) is a hole 350 that penetrates in the fuel flow direction (in FIG. 8A, 350a, 350b, and 350c). May be included).

  As described above, by providing the hole 350 in the burner catalyst 214, a part of the fuel passes through the hole 350 without catalytic combustion. When the fuel passes through the hole 350, heat is taken away from the surrounding exhaust gas or the vaporized fuel gas, so that the burner catalyst 214 is maintained at the assumed temperature for use. It is possible to perform filter regeneration processing.

  Further, as shown in FIG. 8B, the burner catalyst 214 is composed of one or more non-catalysts composed of one or more catalyst layers 352a whose base material is coated with a catalyst and a base material which is not coated with a catalyst. For example, the layers 352b may be alternately stacked.

  In the non-catalyst layer 352b, catalytic combustion does not occur and no heat is generated, so the temperature of itself does not increase. Since the heat generated when the fuel comes into contact with the catalyst layer 352a and the catalyst combustion occurs is transferred to the non-catalyst layer 352b, the catalyst layer 352a is cooled, and the burner catalyst 214 is maintained at the assumed use temperature. Even if catalytic combustion is promoted, the filter regeneration process can be stably performed.

  As described above, the burner apparatuses 200 and 300 described above can prevent deterioration due to exceeding the expected use temperature of the catalyst.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  INDUSTRIAL APPLICABILITY The present invention can be used for a burner device that raises the temperature of exhaust gas from a diesel engine by burning fuel.

DESCRIPTION OF SYMBOLS 100 ... Diesel engine 110 ... Exhaust path 130 ... Diesel oxidation catalyst 200, 300 ... Burner apparatus 210 ... Inlet path 212 ... Combustion chamber 214 ... Burner catalyst 216 ... Combustion fuel supply part 222 ... Cooling pipe 224 ... Temperature detection part 226, 326 ... Cooling control unit 328 ... heat dissipation unit

Claims (8)

A burner device disposed in a front stage of a diesel oxidation catalyst for oxidizing exhaust gas in an exhaust path of a diesel engine,
A burner catalyst that promotes oxidation of the fuel;
A combustion fuel supply section for supplying fuel to the burner catalyst;
A cooling pipe through which a coolant for cooling the burner catalyst circulates;
A burner device comprising: A temperature detector for detecting the temperature of the burner catalyst;
When the detected temperature of the burner catalyst exceeds a predetermined value, a cooling control unit that starts circulation of the coolant;
The burner device according to claim 1, further comprising: A burner device disposed in a front stage of a diesel oxidation catalyst for oxidizing exhaust gas in an exhaust path of a diesel engine,
A burner catalyst that promotes oxidation of the fuel;
A combustion fuel supply section for supplying fuel to the burner catalyst;
A cooling control unit for controlling the fuel supplied by the combustion fuel supply unit to an amount exceeding an equivalence ratio of 1;
A burner device comprising: A temperature detector for detecting the temperature of the burner catalyst;
When the detected temperature of the burner catalyst is equal to or less than a predetermined value, the cooling control unit supplies an amount of fuel with an equivalence ratio of 1 or less to the combustion fuel supply unit to determine a predetermined value. The burner device according to claim 3, wherein an amount of fuel having an equivalent ratio greater than 1 is supplied to the combustion fuel supply unit when the fuel ratio exceeds 1. A burner device disposed in a front stage of a diesel oxidation catalyst for oxidizing exhaust gas in an exhaust path of a diesel engine,
A burner catalyst that promotes oxidation of the fuel;
A combustion fuel supply section for supplying fuel to the burner catalyst;
A heat dissipating part that is arranged in the exhaust path and radiates heat generated by the burner catalyst to exhaust gas passing through the exhaust path;
A burner device comprising:   The burner apparatus according to any one of claims 1 to 5, wherein the burner catalyst has a hole penetrating in a fuel flow direction.   The burner catalyst has a structure in which one or a plurality of catalyst layers in which a base material is coated with a catalyst and one or a plurality of non-catalyst layers composed of a base material that is not coated with a catalyst are laminated. The burner device according to any one of claims 1 to 6. An inflow path through which exhaust gas diverted from the exhaust path flows;
A combustion chamber provided with the burner catalyst, combusting a mixture of the exhaust gas and fuel, and causing the exhaust gas after combustion to flow out to the exhaust path;
A combustion flow rate limiting mechanism for limiting the flow rate of the exhaust gas flowing into the combustion chamber from the inflow path;
The burner device according to any one of claims 1 to 7, further comprising: