WO1980000362A1

WO1980000362A1 - Device for purifying exhaust gas of diesel engine

Info

Publication number: WO1980000362A1
Application number: PCT/JP1979/000194
Authority: WO
Inventors: Y Suzuki; T Tokuhiro; Y Iwasawa; T Komine; K Chiba; Y Kajioka
Original assignee: Shimizu Construction Co Ltd; Y Suzuki; T Tokuhiro; Y Iwasawa; T Komine; K Chiba; Y Kajioka
Priority date: 1978-07-27
Filing date: 1979-07-26
Publication date: 1980-03-06
Also published as: GB2040182B; EP0020766A1; EP0020766B1; SE8001507L; DE2953010C2; DE2953010T1; EP0020766A4; GB2040182A; SE441027B

Abstract

This device for purifying the exhaust gas of a diesel engine incorporates heat resisting filters (6, 7) provided at the upstream side of a catalytic layer (9) to completely remove black smoke particles in the exhaust gas by means of the filtering operation of the filters (6, 7) to thereby prevent the adverse effect caused by the particles adhered onto the catalytic layer (9). The heat resisting filters (6, 7) can be easily recovered by burning and removing the adhered black smoke particles. Further, this device also incorporates a heat resisting filter (24) and a catalytic layer (26) formed in hollow, cylindrical shape and laminated together. A high pressure burner (28) or a negative pressure generator (33) are provided for blowing hot gas into the filter (24) when recovering the filters. The heat resisting filter (24) and the catalytic layer (26) are contained within a case (21) in a compact manner.

Description

Exhaust gas purification equipment for diesel engines

The present invention relates to an exhaust gas purification device for a diesel engine installed in a general vehicle or a building such as a construction machine or a diesel bus truck. In this regard, exhaust gas purification of diesel engines is a process that can reliably remove black smoke particles, harmful gases and gases from diesel engine exhaust gas over a long period of time. Related to the device.

Background technology

Conventionally known diesel engine exhaust / gas purifiers include the following.

(a) In the exhaust gas exhaust line of the diesel engine, a device for removing black smoke such as a circulating π and a catalyst layer are provided.

() A device equipped with a flush-type black smoke removal device that blows exhaust gas into water or sprays water into the exhaust gas in a mist state, and a catalyst layer.

In the case of (a) above, the inertial dust collection method such as cyclone is effective for dust with a particle diameter of several ^ or more. It is not effective for smaller particles, and most of the black smoke particles in the exhaust gas of diesel engines are collected by the inertial dust collection method such as a cycle mouth. The particle size is too small for cleaning, and therefore, the cyclone cannot sufficiently remove the black smoke particles in the exhaust gas of the diesel engine, making the catalyst more prone to prolonged flight. Black smoke particles adhere to the surface, deteriorating the catalytic function, making it impossible to remove fuel and harmful gases (carbon monoxide, hydrocarbons, etc.). For this reason, the catalyst must be heated and regenerated. If the catalyst is exposed to such a high temperature, the function of the catalyst deteriorates, and the catalyst may be damaged by heat. Further, in the above-mentioned (), the flush-type black smoke removing device is capable of sufficiently removing black smoke, but has a drawback that a large amount of water vapor is generated, which is discharged as white smoke and obstructs the view. If necessary, it is time-consuming to maintain the cleaning water and replenish the washing water.In addition, to completely remove odors and harmful gases, the exhaust gas temperature at the inlet of the catalyst layer must be adjusted. It is necessary to maintain the temperature at 300 ° C. (up to 500 ° C., but if the exhaust gas is rinsed with a flush-type black smoke remover, the temperature of the exhaust gas will drop, so the catalyst layer will be flushed It cannot be incorporated on the downstream side of the smoke removing device, and therefore, the black smoke particles are added to the catalyst layer. The disadvantages were inevitable.

Accordingly, the present invention provides a heat-resistant filter that removes black smoke particles upstream of the catalyst layer without the disadvantages of the conventional exhaust gas purifying device of diesel engines. Efficient for a long period of time

(O PI It is an object of the present invention to provide a diesel engine exhaust gas purification device capable of purifying exhaust gas.

In addition, the present invention provides a very simple structure in which black smoke particles captured by a heat-resistant filter are burned and removed in a state where exhaust gas is further passed. The purpose is to provide an exhaust gas purification device for zell engine.

Disclosure of the invention

According to the present invention, a heat-resistant filter for removing black smoke particles in the exhaust gas is provided on the upstream side of the exhaust gas purification pipe of the diesel engine, and on the downstream side. Is equipped with a catalytic converter that removes odors and harmful gases from the exhaust gas. In addition, the heat-resistant filter has a black smoke trapped in the filter. A regenerator that burns and removes particles is provided. This makes it possible to prevent black smoke particles from being added to the catalyst layer by completely removing the black smoke particles by the filtering action of the heat-resistant filter, which is favorable over a long period of time. In addition, black smoke particles trapped in the heat-resistant filter can be extremely easily burned and removed by a regenerator. It becomes a gas purification device.

In addition, the present invention provides the improved heat-resistant filter of the above-described cleaning device, which is capable of burning and removing black smoke particles collected by the heat-resistant filter even when exhaust gas passes. It is a configuration that can be performed, and as a result, a small-sized computer OMPI IPO can be realized. It is connected to a clean diesel engine exhaust gas purifier.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram showing one embodiment of an exhaust gas purifying apparatus for a diesel engine according to the present invention, and FIGS. 2 to 5 show other embodiments. Fig. 2 is a longitudinal side view of the purification device, Fig. 3 is a cross-sectional view taken along the line A-A in Fig. 1, and Figs. 4 and 5 are implementations in this embodiment. FIG.

BEST MODE FOR CARRYING OUT THE INVENTION In order to explain the present invention in more detail, this will be described below with reference to the accompanying drawings. '

In FIG. 1, reference numeral 1 denotes a diesel engine, 2 denotes a starting end of an exhaust gas purification pipe of the diesel engine, and two pipes are provided from the starting end 2 of the gasification pipe. The branch pipes 3 and 4 are formed to be branched, and a switching valve 5 is provided at the base of the branch pipes 3 and 4, and exhaust gas is supplied to any one of the branch pipes 3 and 4 for 10,000. 6 and 7 are heat-resistant filters provided in the valley branch pipes; 5 and 4, and the heat-resistant filters 16 and 7 are made of metal. It is made of fiber, and a layer of sai-type metal fiber, which corresponds to the particle size distribution of black smoke, is laminated to have a predetermined thickness, and has a cylindrical or cylindrical shape. It is configured in a disk-shaped combination.

3a, 3b and 4a, 4b are branch lines formed by branch lines 3 and 4, and branch lines 3a, 3b 4a communicates directly with the exhaust pipe 8, and the branch pipes 3b and 4b communicate with the catalyst converter 9. The outlet side of the catalyst converter 3 is connected to the exhaust pipe 8. They are in communication. Reference numerals 10 and 11 denote switching valves provided in the branch pipes 3a and 3b and 4-a and b, and the switching valves {0 and〗} are operated to switch the branch valves. The pipes 3 and 4 can be switched between a state in which they communicate directly with the exhaust pipe 8 and a state in which they communicate with the catalyst converter S. Reference numerals 2 and 13 denote regeneration pipes provided in the branch pipes 3 and 4, and the regeneration pipes 12 and 13 are connected to the inlet sides of the heat resistant filters 16 and 7, respectively. In addition, a switching valve 15 is provided at the inlet〗 4 of each of the regeneration pipes 12, 13, and a burner の 6 is seen through the blower〗 7. The black smoke particles clogged in the filters 6 and 7 can be burned off by being sent to the filters 6 and 7, and thus the heat-resistant filters can be removed. There are six or seven playback devices. When the black smoke particles are burned, the blower 17 supplies air from the outside because the amount of residual oxygen in the exhaust gas of the engine is small and it is difficult to completely burn it. This is to achieve complete combustion of smoke particles.

Reference numerals 18 and 19 denote differential pressure gauges provided on the heat resistant filters 16 and 7, and the differential pressure gauges〗 8 and 13 are the outlet side and the inlet of the heat resistant filters 16 and 7. It is connected to the mouth and can detect the blockage of black smoke particles in the heat resistant filters 6 and 7. Although not shown, the differential pressure gauge 18

ΟΜΡΙ_ WIPO Based on the detection of blockage of the heat-resistant filters 16 and 7 by 19, the switching valves 5, 10 and 11 are automatically inverted to switch the flow of exhaust gas. The black smoke particles adhering to the heat-resistant filters 6 and 7 by sending hot air to the heat-resistant filters 6 and 7 by operating the air blower 17 and the blower 17 and the blower 17 Can be burned off.

In the above description, the diesel engine T is driven while the switching valves 5, 10, 0, 11 and 15 are switched as shown in the figure. The exhaust gas of the air flows through the branch line 3 from the oxidation line start end 2, passes through the heat-resistant filter 6, and further passes through the branch line 3 b, and becomes a catalytic converter. One _g flows out and is discharged to the atmosphere through the exhaust pipe 8. In this case, since the heat resistant filter 16 is of a filtration type, it can actually collect even relatively small-diameter black smoke particles, and the black smoke particles in the exhaust gas are completely eliminated. Hazardous gases (carbon monoxide, hydrocarbons, etc.) and odors in the exhaust gas are harmless and odorless due to the oxidation of the catalyst filled in the catalyst converter 13. Carbon dioxide gas is oxidized and decomposed, but the black smoke particles in the exhaust gas are heat-resistant.Because the filter has already been removed, the black smoke particles are prevented from adhering to the catalytic converter 3. Thus, it can be used for a long time without impairing the function of the catalyst.

When the number of black smoke particles increases in the heat resistant filter 16, the pressure drop in the heat resistant filter 6 increases.

OMPI WIPO Therefore, the differential pressure gauge〗 8 detects the blockage of the heat-resistant filter 16, and automatically switches the switching valves 5, 10, 11, 15 based on the clogging, and detects the exhaust gas. Through the branch line 4 and the heat-resistant filter 17 to continuously purify the air, and operate the burner 16 and the blower 17 to operate the heat-resistant filter on the clogging side. The hot air is sent to the filter 6 and the black smoke particles trapped in the heat-resistant filter 16 are completely burned, and the heat-resistant filter 6 is heated in a relatively short time. It is for regenerating. Exhaust gas in the regenerating operation is directly discharged from the exhaust pipe 8 through the branch pipe 3a. When the regeneration operation is completed, the pressure drop in the heat resistant filter 6 decreases,

18 detects this and sends a signal to stop the operation of the burner〗 6 and the blower〗 7.

In the embodiment shown in FIG. 1 described above, two heat-resistant filters are provided, and these two heat-resistant filters are used.

However, when the heat-resistant filter is regenerated, the exhaust gas is supplied to the heat-resistant filter. By allowing the heat to pass through, the heat-resistant filter can be made into only one system, and the purification device can be configured as a small compact. Another embodiment of the present invention provided with the heat-resistant filter of only this type 1 gun will be described in detail with reference to FIGS. 2 to 5. FIG.

21 is a case provided in the exhaust gas exhaust passage of the diesel engine, and this case 21 is a hollow circle.

OMPI_ WIPO It is formed in a cylindrical shape, and an exhaust gas inlet 22 is formed on the peripheral surface of one end of the case 21, and the exhaust gas flows out to the other end ½ of the case 21. 23 is formed.o 24 is a heat-resistant filter housed in case 21.-This heat-resistant filter 24 is It is configured by winding a metal fiber or the like formed in a hollow shape into a hollow cylindrical shape, and is configured by a combination of metal fibers having different wire diameters as described above. Heat resistant filter

The end face of the inlet 24 on the side of the inlet 22 is sealed by a cover 25, and the end face of the outlet 23 on the side is opened to communicate with the outlet 23. ing. Reference numeral 26 denotes a catalyst layer accommodated in the case 2〗. The catalyst layer 26 is formed by winding a spongy gold layer catalyst into a hollow cylindrical shape. It removes odors and harmful gases (carbon monoxide, hydrocarbons, etc.) in the exhaust gas using a platinum catalyst or the like. The catalyst layer 26 is located inside the hollow cylindrical heat-resistant filter 24, that is, on the downstream side, and is laminated with the heat-resistant filter 24. It is provided. Reference numeral 27 denotes a partition plate provided on the outflow P 23 side of the case 21, and the partition plate 27 is used to separate the inlet 22 side and the outlet 23 side of the case 21. Exhaust gas from the inlet 22 is discharged to the outlet 23 only after passing through the heat-resistant filter 12 and the cylindrical peripheral surface of the catalyst layer 26. O

28 is airtight at the end of the case 22 at the inlet 22 side

OMPI The high-pressure burner 28 is provided between the inflow port 22 and the outflow port 23 of the case 21, that is, the heat-resistant filter 12. The heat-resistant filter is detected by a differential pressure gauge (not shown) that detects the pressure difference between the inside and outside of the catalyst layer 4 and the catalyst layer 26. This allows the diesel engine to operate, that is, when the exhaust gas is being sent, so that hot air can be sent through the heat-resistant filter 24 to You can play router 24. Reference numeral 23 denotes a high-pressure combustion air intake provided in the high-pressure parner 28. In addition, this high-pressure

Measures have been taken against pressure fluctuations of the exhaust gas sent to 21. Reference numeral 30 denotes a radiator plate of the high-pressure burner 28, which is formed in a tubular shape and is provided so as to surround the flame of the high-pressure burner 28. In addition, a large number of holes 3.0a and 30a are formed in the peripheral surface of the Q tip.

Here, 31 is a heat insulating material provided in the case 21, and 32 is a mounting member of the case 2〗.

FIG. 4 and FIG. 5 show an embodiment of this embodiment. That is, in the above embodiment, the regenerating device of the heat-resistant filter 24 is constituted by the high-pressure parner 28:

The heat-resistant filter is replaced by a normal low-pressure (atmospheric pressure) spanner and a negative pressure generator formed in the exhaust gas discharge path. This constitutes the playback device of the router 24. Numeral 33 denotes a negative pressure generating section formed in the exhaust pipe 34 on the upstream side of the case 21. This negative pressure generation ^ 33, as shown in FIG. As shown in Fig. 5, the exhaust pipe 34 is divided, and the diameter of the exhaust pipe 34 is changed, as shown in Fig. 5. The low-pressure parner 35 is connected to the conduit provided in the negative pressure generator 33.

The hot air of the low-pressure parser 35 is sent into the case 21 by the negative pressure generated by the passage of the exhaust gas.

In the above, if it is assumed that the diesel engine is operating, the exhaust gas from the diesel engine is fed into the case 21 from the inlet 22. , Case

It passes through the heat resistant filter 24 and the catalyst layer 26 in 21 and is discharged from the outlet 23. The black smoke particles contained in the exhaust gas are reliably collected and removed by the heat-resistant filter 24 when passing through the heat-resistant filter 24. However, odors and harmful gases (carbon monoxide, hydrocarbons, etc.) in the exhaust gas are removed by the action of the catalyst when passing through the catalyst layer 26. Black smoke particles in the exhaust gas are heat-resistant filters

Since it is completely removed by the filtering action of 24, the black smoke particles are prevented from adhering to the catalyst layer 26, and thus the catalyst function of the catalyst layer 26 can be maintained well over a long period of time.

― OMPI When the amount of black smoke particles collected by the heat-resistant filter 24 increases, the pressure difference between the inlet 22 and the outlet 23 of the case 21 increases. This pressure difference is detected by a differential pressure gauge (not shown), and when the pressure reaches a set value, the high-pressure spanner 28 is activated. Hot air is sent into the case 21 by the operation of the high-pressure parner 28, and the black smoke particles collected by the heat-resistant filter 124 are completely removed by the hot air. After the heat is removed, the heat-resistant filter 24 is regenerated, and when the heat-resistant filter 24 is regenerated, the pressure difference in the case 21 is reduced. 28 is to be deactivated. In this case, the radiator plate 30 is glowed red by the operation of the high-pressure parner 28, and the exhaust gas sent from the inflow P 21 blows to the peripheral surface of the base end of the radiator plate 30. This heats while rotating the cylindrical peripheral surface of the radiator plate 30 in a helical manner, passes through the heat-resistant filter 24, and completely burns and removes black smoke particles. is there.

Also in the embodiment shown in FIGS. 4 and 5, when the heat resistant filter 24 is clogged, the same as described above, the differential pressure gauge (not shown) detects the clogging, The low-pressure burner is activated, and the hot air of the low-pressure burner 35 is sent to the case 21 by the negative pressure of the negative-pressure generating section 33, and the black smoke particles of the heat-resistant filter 24 are generated. O Industrial applicability

In short, the exhaust gas purifying apparatus for a diesel engine according to the present invention is a construction machine or a diesel engine.

General vehicles such as passes and trucks are installed in buildings. The diesel engine is small and has high performance. It has low power and easy maintenance. It has become possible to provide an exhaust gas purifying device of a new diesel engine.

O PI WIPO

Claims

The scope of the claims

1. The upstream side of the exhaust gas purification line of the diesel engine

In addition to providing a heat-resistant filter for removing black smoke particles in exhaust gas, a catalyst converter for removing odor and harmful gas in exhaust gas is provided on the lower side. In addition, the heat-resistant filter is provided with a regenerating device for burning and removing the black smoke particles trapped in the filter. Purifier. +

2. The diesel engine according to claim 1, wherein the heat resistant filter is formed by combining metal fibers having different wire diameters. ^ Gas gas purifier. .

3. The exhaust gas purifying pipe is formed into a plurality of branch pipes. Each of the branch pipes is provided with a heat-resistant filter. Claims characterized in that the base is provided with a switching valve for allowing the exhaust gas to flow out alternatively to the plurality of branch pipes.

The exhaust gas purifier of diesel engine described in paragraph 1 or paragraph 2.

4. A differential pressure gauge is attached to the heat resistant filter.

4. The diesel engine according to claim 3, wherein the switching operation of the switching valve and the operation of the regenerator are automatically controlled by sensing the pressure by the differential pressure gauge. Engine exhaust gas purification equipment.

ΟΜΡΙ WIPO

5. A heat-resistant filter that removes black smoke particles in the exhaust gas is provided in the exhaust gas exhaust path of the diesel engine, located at the upstream side of the catalyst layer. The heat-resistant filter is provided with a regenerating device for burning and removing the black smoke particles collected in the filter. The heat-resistant filter, the catalyst layer and Is housed in a single case provided in the exhaust gas discharge path, and the regenerator of the heat-resistant filter can be operated even when exhaust gas is discharged. Diesel Engine exhaust gas purification equipment.

6. The heat-resistant filter accommodated in the case is formed in a hollow cylindrical shape, and the exhaust gas is allowed to flow out through the cylindrical peripheral surface of the heat-resistant filter. An exhaust gas purifying apparatus for a diesel engine according to claim 5, wherein the exhaust gas purifying apparatus is characterized in that:

7. A catalyst layer accommodated in the base is formed into a hollow cylindrical shape, and the catalyst layer is formed into a hollow cylindrical heat-resistant filter.

-The exhaust gas purification and re-installation of the diesel engine described in claim 6 characterized in that it is provided in a laminated form on the o.

8. The regenerator of the heat-resistant filter is constituted by a high-pressure burner provided in a case in an airtight manner in the case. A diesel engine exhaust gas purifying apparatus as described in paragraph or paragraph 7.

9. The heat-resistant filter is composed of a negative pressure generating section provided in the exhaust path on the upstream side of the case and a low-pressure spanner provided in the negative pressure generating section. The exhaust gas purifying apparatus for a diesel engine according to any one of claims 5 to 6, and 7 or 8, characterized in that:

ΟΜΡΙ

A, WIPO