JPS6252126B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that electrically collects soot particles contained in exhaust smoke emitted from an internal combustion engine and burns and removes them.

Generally, the exhaust smoke emitted from internal combustion engines, especially diesel engines, contains many soot particles with a diameter of 2 microns or less. If, for example, a conventional centrifugal separator is used as a device for capturing this substance, the exhaust resistance of the device will be extremely large, and the device will also be large. Furthermore, if a filter device is used to collect the particles, the filter may become clogged with the collection, resulting in an increase in back pressure. Furthermore, in addition to these methods, a method of promoting the oxidation of soot using a catalyst is also considered, but at present no catalyst with sufficient low-temperature activity has been found.

On the other hand, there is electric dust collection, in which soot particles charged by corona discharge are deposited on the inner surface of a cylindrical dust collecting electrode using Coulomb force caused by an electric field. this is,
In general, it is possible to collect even extremely fine particles (0.1 microns) with high collection efficiency, and it is said that it can be used in environments with temperatures and pressures comparable to those of automobile exhaust smoke. Furthermore, it has many advantages such as low power consumption and extremely low ventilation loss. However, as a drawback, re-scattering phenomena and reverse ionization phenomena may occur due to the accumulation of soot on the dust collecting electrode, and current leakage due to fouling of the interelectrode insulator and treatment of the collected dust may resolve the problem. There is a problem.

The exhaust gas dust collector of the present invention eliminates the above-mentioned drawbacks and collects a large amount of soot and the like and burns it. That is, the device of the present invention includes a tubular main body through which exhaust smoke from an internal combustion engine passes and whose inner wall surface serves as a dust collecting electrode, a dust collecting box provided at the bottom of the main body and opening into the internal space of the main body. It consists of an ignition device installed inside the dust collection box, a rotor that rotates along the inner wall surface of the main body, and a center electrode installed in the center of the internal space of the main body, and an electrostatic voltage is applied between the electrodes to collect dust. This method is characterized by depositing soot on the electrodes, collecting the deposited soot in a dust collection box with a rotor, and igniting and incinerating it with an ignition device.

The following is a description based on examples.

An embodiment of the present invention is shown in FIGS. 1 and 2. FIG. This device consists of a tubular main body 1 made of metal or conductive material that also serves as a dust collection electrode, a long rectangular parallelepiped dust collection box 2 installed at the bottom of the main body 1 and opening into the internal space of the main body 1, and a dust collection box 2 inside the dust collection box 2. an ignition device 3 consisting of an electric resistance heating coil provided in the main body 1; a rotor 4 that is pivotally supported at the center of one end surface of the main body 1 and rotates along the inner wall surface of the main body 1; and a rotor 4 fixed at the center of the other end of the main body 1; It consists of a center electrode 5 provided at the center of the internal space.

An inlet 11 for introducing exhaust smoke is opened in the peripheral wall near one end of the main body 1, and an inlet pipe 12 for introducing exhaust smoke (indicated by the two-dot broken line in FIG. 2) is opened there.
are combined. On the other hand, on the peripheral wall opposite to the inlet 11 near the other end of the main body, there is an outlet 13 for exhaust smoke.
(shown by the broken line in FIG. 1) is open, and a flue pipe 14 for discharging exhaust smoke is connected thereto. Outlet 13
The central axis 4 of the rotor 4 is located at the center of the end of the main body 1 close to
1 is provided with an opening 15 through which it passes. A disk-shaped ceramic partition wall 16 having a center hole is provided at the opposite end of the opening 15, and a lid 1 is provided on the outside of the partition wall 16.
7 is provided. An air chamber 18 is formed between the partition wall 16 and the lid 17. Lid 17
A screw hole is provided in the center of the center electrode 5.
is screwed on.

The dust collection box 2 is integrally connected to the lower part of the main body 1,
The upper end of the dust collection box 2 opens into the internal space of the main body 1. At the end of the dust collection box 2 near the inlet 11 of the main body 1, there is an air introduction pipe 21 for introducing air for burning soot, etc., and at the opposite end there is an exhaust pipe 22 for discharging combustion gas. It is provided. The exhaust pipe 22 is connected to the exhaust pipe 14 of the main body 1, and the combustion gas is discharged into the exhaust pipe 14.

The ignition device 3 consists of a coiled nichrome wire,
It is provided near the air introduction pipe 21 inside the dust collection box 2. The terminal of the nichrome wire passes through the wall of the dust collection box 2 in an electrically insulating manner and is connected to a power source (not shown).

The rotor 4 includes a central shaft 41 , a rotor member 42 having approximately the same diameter as the inner diameter of the main body 1 , and three pillars 43 connecting the central shaft 41 and the rotor member 42 . The rotor member 42 has rings 44 located at each end thereof.
and three pawl plates 45 connecting the ring 44.
It becomes more. A central shaft 41 of the rotor 4 is rotatably supported in the opening 15 of the main body 1, and the other end of the central shaft 41 protrudes outside the main body 1, and a gear 4 is fixed thereto.
6 by an external mechanism (not shown). As the rotor 4 rotates, a pawl plate 45 rotates along the inner wall surface of the main body 1, scraping off soot and the like adhering to the inner wall surface and collecting it in the dust collecting box 2.

The center electrode 5 consists of a rod-shaped electrode member 51 having a large number of protrusions formed on its surface, a ceramic member 52 covering the other end, and a terminal 53 at the tip thereof. A metal screw portion that engages with the central screw hole of the lid 17 of the main body 1 is fixed to the outer surface of the ceramic member 52. The center electrode 5 is fixed to the lid 17 and the air chamber 1
8 and the central hole of the partition wall 16, and is disposed in the center of the internal space of the main body 1. A ring-shaped gap is formed between the inner wall surface of the center hole of the partition wall 16 and the outer surface of the ceramic member 52 of the center electrode 5, and air is ejected from the air chamber 18 into the internal space of the main body 1 through this gap. do. Note that air is supplied from the outside through an air supply pipe 19 of the lid 17.

The exhaust smoke processing device of this embodiment has the above configuration. Exhaust smoke from the internal combustion engine enters the main body 1 through the inlet 11 of this device, and an electrostatic voltage is applied between the electrode member 51 of this electrode and the inner wall surface of the main body 1, which is the opposite electrode, with the center electrode 5 as the negative electrode. When a corona discharge is generated between the two electrodes, soot and the like contained in the exhaust smoke are charged by the corona discharge, and are attracted and attached to the inner wall surface of the main body 1 by Coulomb force. The exhaust smoke from which soot and the like have been removed is discharged from the outlet 13 to the outside through the outlet smoke pipe 14. On the other hand, the rotor 4 is driven by external power via the gear 46, and the pawl plate 45 moves along the inner wall surface of the main body 1 due to the rotation of the rotor 4, and the soot etc. adhering to the inner wall surface of the main body 1 are removed. The soot, etc. adhering to the wall surface is scraped off, the soot, etc. is further transferred downward, and the soot, etc. is finally collected in the dust collection box 2. The soot and the like collected in the dust collection box 2 are intermittently ignited by the igniter 3 and burned by the air sent from the air introduction pipe 21, and the combustion gas is discharged from the exhaust pipe 22. more excluded.

In this device, soot and the like adhering to the inner wall surface of the main body 1 are periodically scraped off by the pawl plate 45, so that there is little re-scattering of soot and the like. In addition, since the dust collection electrode is formed along the inner wall surface of the main body 1, the dust collection area is wide.
The efficiency of collecting dust such as soot is correspondingly high. Furthermore, partition wall 1
The air ejected from the ring-shaped gap between the center hole 6 and the center electrode 5 blows away soot and the like, making it difficult for soot and the like to adhere to the surface of the center electrode 5. For this reason, electrical leakage due to soot adhesion is more effectively prevented.

In this device, a cylindrical body is used as the main body 1, but the rotor can rotate along the inner wall surface of the main body.In other words, the main body can be made by making a rotor of any shape and centering around the axis of the rotor. It is sufficient that the inner wall surface has the shape of the rotating body formed by rotating the inner wall surface. Further, in this embodiment, the inlet smoke pipe 12 and the outlet smoke pipe 14 for the exhaust smoke are installed perpendicularly to the peripheral wall of the main body 1, but for example, as shown in FIG. It is also possible to provide an inlet flue 12' and an outlet flue 14'.

The shape of the dust collection box 2 is also not limited to the shape of this embodiment. Further, the air introduction pipe 21 and the exhaust pipe 22 for burning the collected soot and the like are not necessarily required. However, in this case, it is necessary to supply sufficient air into the dust collection box 2 from the internal space of the main body 1. If the soot collected in the dust collection box 2 is scattered due to the flow of gas inside the main body 1, a wire mesh or a perforated plate should be installed between the main body 1 and the dust collection box 2, so that the gas can be scattered inside the dust collection box 2. It can also prevent re-scattering by blocking the water from entering the water.

The center electrode 5 is not necessarily limited to the shape of this embodiment. Moreover, not only one but multiple pieces can be used. The voltage between the two electrodes is set to the voltage necessary for corona discharge to occur. The voltage is preferably a direct current voltage, but if soot etc. can be partially combusted within the main body 1, a pulse voltage can also be used.

The ignition device 3 and rotor 4 are also not limited to the present embodiment. As for the ignition device 3, a flame burner or the like may be used as long as it is capable of igniting soot or the like. Further, the rotor 4 may be of any type as long as it can rotate along the inner wall surface of the main body 1. The rotational speed of the rotor 4 should depend on the speed at which soot and the like adhere to the inner wall surface of the main body 1, but in practice it may be one rotation per minute or less.

In order to confirm the effectiveness of the device of this example, the device was attached to the exhaust manifold of a diesel engine and a performance test was conducted against smoke emitted from the engine.

The diesel engine used in the experiment had a displacement of 2188
cc. Operating conditions are rotation speed 2000 rpm, load 6
Kgm, and a DC voltage of minus 17 to 20 KV and a pulsed voltage with a repetition frequency of 500 Hz and a width of 0.3 ms were used at the center electrode. The inner diameter of the main body 1 of this device is 60 mm, and the length is 200 mm. The length of the portion of the center electrode 5 where the protrusion is formed is approximately 150 mm.

Note that in order to prevent soot from adhering to the center electrode 5, air was supplied to the air chamber 18 at a rate of 50 per minute. Further, when burning soot etc. in the dust collecting box 2, air was supplied from the air supply pipe 19 at a rate of 1 per minute. Experiments were conducted under the above conditions, and particles such as soot were measured using the following method. Exhaust smoke emitted from the engine is guided to this device, and after passing through the main body 1, a total of 20 gases are sampled from inside the exhaust pipe 14 at a rate of about 2 per minute through a filter, and soot etc. trapped on the filter are sampled. Changes in particle weight were investigated.

As a result, if a DC voltage is applied to this device,
A weight reduction of approximately 40 ωt% was observed compared to the case where no voltage was applied. Note that the rotational speed of the rotor 4 was 1 revolution/minute. Furthermore, it has been found that the soot collected in the dust collection box 2 is continuously combusted.

When pulse voltage is used in the same device, it is 30Ωt%.
A decrease in weight was observed.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an exhaust gas treatment device that is an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of the same device.
FIG. 3 is a longitudinal sectional view of another device. In the figure, numeral 1 indicates the main body, 2 indicates a dust collection box, 3 indicates an ignition device, 4 indicates a rotor, and 5 indicates a center electrode.

Claims (1)

[Claims] 1. A tubular body through which exhaust smoke from an internal combustion engine passes and whose inner wall surface serves as a dust collection electrode, a dust collection box provided at the bottom of this body and opening into the internal space of the main body, and a dust collection box provided within the dust collection box. The device consists of an ignition device, a rotor that rotates along the inner wall surface of the main body, and a center electrode installed in the center of the internal space of the main body, and an electrostatic voltage is applied between the electrodes to cause soot etc. to adhere to the dust collecting electrode. A device for treating exhaust smoke from an internal combustion engine, characterized in that a rotor collects adhering soot in a dust collection box, and ignites and incinerates it with an ignition device.