JP2567624Y2 - Diesel engine exhaust particulate treatment equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust particulate processing apparatus for a diesel engine.

[0002]

2. Description of the Related Art Conventionally, an exhaust particulate processing apparatus for a diesel engine of this type is disclosed in, for example, Japanese Utility Model Laid-Open No. 61-128.
No. 325 is known.
This will be described with reference to FIG. In the figure, reference numeral 1 denotes a diesel engine, to which an exhaust passage 2 provided with a trap 3 is attached. Further, pressure sensors 4 and 5 are attached before and after the trap 3. Both pressure sensors 4,
5 communicates with the control device 6. An on-off valve 7 is provided in the exhaust passage 2 downstream of the trap 3. The on-off valve 7 is opened and closed by a drive circuit 8 operated by the control device 6. 9 is a silencer.

[0003] In the exhaust gas treating apparatus of the diesel engine thus configured, the exhaust particles discharged from the diesel engine 1 are collected by the trap 3, and the exhaust gas from which the exhaust particles have been removed is silenced by the silencer 9. Released into the atmosphere. Then, the pressure sensor 4 and 5 which is provided before and after the trap 3, the exhaust gas pressure measured to monitor the difference between the exhaust gas pressure P ₁ and P ₂ in the control device 6, when the difference is greater than or equal to the specified value Then, it is determined that the trap 3 is clogged with the exhaust particulate, and a command to close the on-off valve 7 is issued through the drive circuit 8. At the same time, the diesel engine 1 is put into a load operation state, and high-temperature exhaust gas is
The inside temperature is raised to a temperature at which the exhaust particulate burns, and the regeneration process is performed for a predetermined time. Thereafter, the control device 6 issues a command to open the on-off valve 7 through the drive circuit 8, and returns to the normal operation state.

[0004]

However, in the above exhaust gas treatment apparatus for a diesel engine, one trap 3 is provided.
The trap 3 is clogged, and the trap 3 is clogged based on the differential pressure detected by the pressure sensors 4 and 5, and the trap 3 is regenerated. In an operation state in which a large amount of exhaust particulates is emitted, it is difficult to remove all of them with one trap 3.

Accordingly, for example, Japanese Patent Application Laid-Open No. 62-99610
As disclosed in JP-like, although the two trap has been proposed that arranged in series, this is contrary At a normal operation, the trap becomes exhaust resistor, there is a possibility of reducing the engine output . The present invention has been made to solve such a conventional problem, and an object of the present invention is to treat exhaust particulates of a diesel engine capable of reliably collecting exhaust particulates and preventing a decrease in engine output. It is to provide a device.

[0006]

According to the present invention, there is provided an exhaust particulate processing apparatus for a diesel engine, comprising: an exhaust passage of the diesel engine; a first trap provided with a regenerating device provided in the exhaust passage; and a downstream side of the first trap. A white smoke removing device provided in an exhaust passage of the vehicle; a first switching valve provided in an exhaust passage between the white smoke removing device and a downstream side of the first trap; a downstream side of the first trap and a white smoke removing device A bypass passage provided in an exhaust passage between the second trap and a second trap provided with a regenerating device provided in the bypass passage; a second switching valve provided in a bypass passage upstream of the second trap; A first burner injection device that inserts a nozzle upstream of one trap, a second burner injection device that inserts a nozzle upstream of the second trap, at least two pressure sensors provided in an exhaust passage, From sensor A control device that controls the on / off operation of the regeneration device based on the detected value, the opening / closing operation of the first switching valve and the second switching valve, and the on / off operation of the first combustion assisting material injection device and the second combustion assisting material injection device. Equipped, during normal operation,
Based on the command of the control device, open the first switching valve,
When the second switching valve is closed and the differential pressure is equal to or higher than a predetermined value based on the detection value from the pressure sensor, the regenerating device of the first trap is operated by a command from the control device, and the first combustion assisting material injection device is operated. injecting operation to improve combustion and the exhaust particulate collecting quantity by the first trap when obtaining super, based on a command from the controller, it opens the second switching valve of the bypass passage, closing the first change-over valve , While operating the playback device,
The second combustion assisting material injection device is operated to inject a combustion assisting material.

[0007]

According to the present invention, during normal operation, the first switching valve is opened, the second switching valve is closed, and the exhaust gas is collected by the first trap based on a command from the control device. Then, when the differential pressure becomes equal to or more than a predetermined value based on the value detected by the pressure sensor, the regeneration device of the first trap is operated by the command from the control device, and the auxiliary combustion material is injected from the first auxiliary fuel injection device. The first trap is regenerated by burning the auxiliary combustion material in the first trap and burning the clogged exhaust fine particles by the heat. The white smoke generated at that time is removed by the downstream white smoke removing device.

[0008] Also, when diesel engine is started, during high load operation, as isochronous blow-off, the exhaust particulate collecting quantity by the first trap if is exceeded, based on the instruction of the control device, a bypass passage The two-way switching valve is opened, the first switching valve is closed, and a two-stage process of passing exhaust particulates through the first trap and the second trap is performed. The auxiliary material is injected from the injection device, the auxiliary material is burned in the second trap, and the exhaust heat burns the clogged exhaust fine particles. The white smoke generated at that time is removed by the downstream white smoke removing device.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a device for treating exhaust particulates of a diesel engine according to an embodiment of the present invention, and reference numeral 11 denotes a diesel engine. An exhaust passage 13 is attached to an exhaust port of the diesel engine 11. In the exhaust passage 13, a first trap 15 with a regeneration device 17 is provided.
White smoke removing device 19, first switching valve 21, bypass passage 23, second trap 25 with regenerating device 27, second switching valve 29, first auxiliary fuel injection device 31, second auxiliary fuel A material injection device 35, a pressure sensor 39, and a control device 41 are provided.

The first trap 15 is provided with a reproducing device 17 made of a conductive material such as a nichrome wire. The playback device 17 is in communication with a battery or the like, and is turned on and off by a command from the control device 41.
A first switching valve 21 is provided in the exhaust passage 13 on the downstream side of the first trap 15. The first switching valve 21 is controlled by a command from the control device 41 so as to be open during normal operation and closed during operation using the second trap 25.

The white smoke removing device 19 removes white smoke generated by burning the auxiliary material supplied from the first auxiliary material injection device 31 and the second auxiliary material injection device 35. The bypass passage 23 is provided in the exhaust passage 13 between the downstream side of the first trap 15 and the upstream side of the white smoke removing device 19. In the bypass passage 23, the second switching valve 2
9 and a second trap 25 with a reproducing device 27 are provided.

The second trap 25 is provided with a reproducing device 27 made of a conductive material such as a nichrome wire. The playback device 27 is in communication with a battery or the like, and is turned on and off by a command from the control device 41.
As the second trap 25, similarly to the first trap 1, an unfired filter called a normal particulate trap filter is used, but a honeycomb-shaped metal filter may be used.

The first fuel injection device 31 is installed so that a nozzle 33 is inserted upstream of the first trap 15. The first combustion assisting material injection device 31 injects a combustion assisting material such as gasoline, volatile oil, or alcohol through a nozzle 33 by a driving device 31A such as a pump. The drive device 31A is turned on / off by a command from the control device 41.

The second fuel injection device 35 is installed so as to insert a nozzle 37 upstream of the second trap 25. Again second combustion improver injection device 35, similarly to the first promoter retardant injection device 31, by a drive device 35A such as a pump, for example, gasoline, gasoline is injected combustion improver such as alcohol through the nozzle 37 Things. Drive 3
5A is turned on / off by a command from the control device 41.

The pressure sensors 39 are provided before and after the first trap 15. Then, the differential pressure of the exhaust gas pressure before and after the first trap 15 is measured. The pressure sensor 39 is in communication with the control device 41. Control device 41
Are the on / off operations of the regenerating devices 17 and 27 based on the detection values from the two pressure sensors 39, the opening and closing operations of the first switching valve 21 and the second switching valve 29 based on signals from a control system (not shown), It controls the on / off operation of the first and second auxiliary fuel injection devices 31 and 35 based on signals from the control system.

Next, the operation of the thus constructed embodiment will be described. During normal operation, the control device 41, which has received a signal from a control system (not shown), issues a command to the drive circuit,
While opening the first switching valve 21, closing the second switching valve 29,
The first trap 15 collects exhaust fine particles. When the pressure difference between the exhaust gas pressures detected by the pressure sensors 39 provided before and after the first trap 15 is equal to or more than a predetermined value, the control device 41 issues a command to the drive circuit to In order to regenerate the fuel, the regenerating device 17 is operated, a combustion aid is injected from the first combustion aid injection device 31, and the combustion aid is burned in the first trap 15, and the heat is clogged. Burn the exhaust particulates.
The white smoke generated at that time is removed by the white smoke removing device 19 on the downstream side.

When the pressure difference between the exhaust gas pressures detected by the pressure sensors 39 provided before and after the first trap 15 becomes equal to or less than a predetermined value, the control device 41 issues a command to the drive circuit to cause the first combustion assisting device. stops the injection of combustion improver from wood implanter 31, it stops the power supply to the reproduction apparatus 17.
This returns to the normal operation state. on the other hand,
Diesel as such as an engine when starting up and high load operation or blow-off, if is exceeded the exhaust particulate collecting amount of the first trap 15, the control unit 41 which receives a signal from a control system (not shown), a drive A command is issued to the circuit to open the second switching valve 29 of the bypass passage 23 and
1 is closed, and a two-step process of passing the exhaust fine particles through the first trap 15 and the second trap 25 is performed, and the exhaust fine particles are collected by both.

At the same time, the control device 41 issues a command to the drive circuit to operate the regenerating device 27 of the second trap 25 and to operate the second combustion material injection device 35 to inject the combustion material from the nozzle 37. Then, in the second trap 25, the auxiliary combustion material is burned, and the heat thereof burns the clogged exhaust particulates. The white smoke generated at that time is removed by the white smoke removing device 19 on the downstream side.

When returning to the normal operation state,
The control device 41 that has received a signal from a control system (not shown)
A command is issued to the drive circuit to perform the above-described processing during normal operation. As described above, according to the present embodiment, the exhaust passage 13 of the diesel engine 11 and the first trap 15 with the regeneration device 17 provided in the exhaust passage 13 are provided.
When, a white smoke removal device 19 provided in the exhaust passage 13 on the downstream side of the first trap 15, first provided in the exhaust passage 13 between the white smoke removal device 19 and the downstream side of the first trap 15 A switching valve 21, a bypass passage 23 provided in the exhaust passage 13 between the downstream side of the first trap 15 and the upstream side of the white smoke removing device 19, and a second trap with a regenerating device 27 provided in the bypass passage 23. 25, a second switching valve 29 provided in the bypass passage 23 on the upstream side of the second trap 25,
The first combustion support material injection device 31 that inserts the nozzle 33 upstream of the first trap 15, the second combustion support material injection device 35 that inserts the nozzle 37 upstream of the second trap 25, and the exhaust passage 13 are provided. Two pressure sensors 39 and a pressure sensor 3
And On'o <br/> off operation of the reproducing apparatus 17, 27 based on a detected value from 9, the opening and closing operation of the switch valve 21 and second switching valve 29, the first promoter retardant injection device 31 and the second combustion support A control device 41 for controlling the on / off operation of the material injection device 35, and during normal operation, based on a command from the control device 41 ,
While opening the first switching valve 21, closing the second switching valve 29,
When reproducing the first trap 15, when the differential pressure is equal to or greater than a predetermined value based on a detected value from the pressure sensor 3. 9, the control device
41, the reproducing device 17 of the first trap 15
Actuates the, by operating the first promoter retardant injection device 31 injecting improve combustion, the exhaust particulate collecting amount of the first trap 15 when obtaining super is the bypass passage 23 on the basis of a command from the controller 41 While opening the second switching valve 29,
Since the first switching valve 21 is closed, the regenerating device 27 is operated, and the second auxiliary combustion material injection device 35 is operated to inject the auxiliary combustion material. Is performed, the second trap 25 is stopped, and the airflow resistance in the exhaust passage 13 can be reduced as compared with the conventional dual type. Also, the first trap 15
In the operation state where it is difficult to collect the exhaust fine particles by the second trap 25, after the processing in the first trap 15, the second trap 25 collects the exhaust fine particles. In addition, in the second trap 25, since the regenerating device 27 of the second trap 25 is operated and the auxiliary material is injected from the second auxiliary material injection device 35, the exhaust fine particles collected here are surely removed. There is no danger of being burned out and flowing out downstream.

Further, the first trap 15 and the second trap 25 have regenerators 17 and 27, and are provided upstream of the regenerators 17 and 27 with the first and second auxiliary fuel injection devices 31 and 35, respectively. Since the combustion assisting material can be injected, the combustion assisting material is burned by the regenerating devices 17 and 27, and the exhaust fine particles clogged by the combustion are burned. As compared with the method of burning fine particles, clogged exhaust fine particles can be reliably burned.

In the above embodiment, the case where the pressure sensors 39 are provided before and after the first trap 15 has been described. However, the pressure sensors 39 may be further provided downstream of the second trap 25 to measure at three points. good. Also, the playback devices 17 and 27
May have a shape and a structure provided in a conventional particulate trap filter.

[0022]

[Effects of the Invention] As described above, in the present invention, during normal operation, only the first trap collects exhaust particulates,
At the time of clogging, the regenerating device of the first trap is operated, and the auxiliary material is injected from the first auxiliary material injection device, the auxiliary material is burned in the first trap, and the exhaust fine particles clogged by the heat. As the conventional method, two traps are not used at the same time as in the conventional method.
Does not increase ventilation resistance. In addition, as compared with a conventional system in which exhaust gas particles clogged by a regeneration device are simply burned, the regeneration can be performed more efficiently. Since the white smoke generated during the regeneration is removed by the white smoke removing device on the downstream side, there is no possibility that the white smoke is released into the atmosphere.

[0023] Also, as in the isochronous diesel engine starting and high-load operation or blow-off, the exhaust particulate collecting quantity by the first trap if is exceeded, based on the instruction of the control device, a bypass passage The two-way switching valve is opened, the first switching valve is closed, and a two-stage process of passing exhaust particulates through the first trap and the second trap is performed. Since the auxiliary material is injected from the injection device, the auxiliary material is burned in the second trap, and the exhaust fine particles clogged by the heat thereof, the exhaust fine particles can be reliably collected.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a configuration of an exhaust particulate processing device of a diesel engine according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a main part in FIG.

FIG. 3 is a configuration explanatory view of a conventional exhaust particulate processing apparatus for a diesel engine.

[Description of Signs] 11 Diesel engine 13 Exhaust passage 15 First trap 17, 27 Regeneration device 19 White smoke removal device 21 First switching valve 23 Bypass passage 25 Second trap 29 Second switching valve 31 First combustion support material injection device 33 , 37 nozzle 35 second auxiliary fuel injection device 39 pressure sensor 41 control device

Claims (1)

(57) [Scope of request for utility model registration] An exhaust passage (13) of a diesel engine (11), a first trap (15) with a regenerating device (17) provided in the exhaust passage (13), and a downstream of the first trap (15) Side exhaust passage (13)
A first switching valve (2) provided in an exhaust passage (13) between the white smoke removing device (19) and the downstream side of the first trap (15).
1) and the downstream side of the first trap (15) and the white smoke removing device (19)
A bypass passageway (23) provided in an exhaust passageway (13) between the upstream side and a second trap (25) with a regenerator (27) provided in the bypass passageway (23); 25), the bypass passage (2
3) a second switching valve (29), a first combustion aid injection device (31) for inserting a nozzle (33) upstream of the first trap (15), and an upstream of the second trap (25). A second combustion assisting material injection device (35) fitted with a nozzle (37) on its side, at least two pressure sensors (39) provided in an exhaust passage (13), and regeneration based on the detection values from the pressure sensors (39). Equipment (1
7, 27), the opening and closing operation of the first switching valve (21) and the second switching valve (29), and the on / off operation of the first auxiliary fuel injection device (31) and the second auxiliary fuel injection device (35). And a control device (41) for controlling the operation. During normal operation, based on a command from the control device (41),
While opening the first switching valve (21), the second switching valve (29)
When the differential pressure based on the detection value from the pressure sensor (39) is equal to or more than a predetermined value, the regeneration device (1) of the first trap (15) is closed.
7) and the first auxiliary fuel injection device (31)
Injecting operation to improve combustion and when the exhaust particulate collecting amount of the first trap (15) obtaining super, based on a command from the control unit (41), the second switching valve of the bypass passage (23) ( Open 29)
The diesel engine according to claim 1, wherein the first switching valve (21) is closed, the regenerating device (27) is operated, and the second auxiliary material injection device (35) is operated to inject auxiliary material. Exhaust particulate processing equipment.