JPH05277313A - Fine particle separating device - Google Patents

Abstract

PURPOSE:To collect fine particles of submicron and to burn them by oxidation to make them harmless in a fine particle-contg. fluid, such as exhaust gas. CONSTITUTION:In a nozzle pipe 2 equipped with an intake 3, a nozzle part 5 through which fine particle-contg. gas is passed to be turned into a high-speed swirling flow, is installed. In a cylindrical case 1 where the high-speed swirling flow is transferred, a bar electrode 12 equipped with a needle electrode part 14 and a cylindrical electrode 15 are installed, and a high-voltage DC power source 25 is connected to form the high-voltage static electric field. Fine particles passing through the static field are charged and agglomerated to be turned into larger particles, making centrifugal separation easy. The fine particles centrifugally separated are burned by oxidation in a burning part 18 of the cylindrical electrode 15 to be made harmless. The burning part 18 is formed, packed with catalytic fiber carried on glass fiber and metal fiber. The fluid after fine particle separation is restored its pressure in a diffuser part 10 of a diffuser pipe 7 and is discharged from a discharge port 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fine particle separator for separating fine particles contained in exhaust gas of an internal combustion engine.

[0002]

2. Description of the Related Art Among harmful components discharged from an internal combustion engine, particulate harmful components called particulates are composed of organic extract (SOF) and dry suit containing carbon as a combustion residue as main components. However, conventionally, these particulate particulates have been removed by a method in which they are collected by a ceramic porous trap, removed when densely packed and burned outside.

However, this method has a disadvantage that small particles of submicron or less cannot be removed and the trap must be replaced regularly.

[0004]

Therefore, the present inventor further developed a method of giving a swirl to the exhaust gas to remove the particulates by centrifugal force, and speeding up with a nozzle,
Invented a device that generates a high-speed swirling flow and separates and removes fine particles by an outstanding centrifugal force (Japanese Patent Application No. 63-22179).
No. 0). However, it was difficult to completely remove submicron particles.

An object of the present invention is to provide a device capable of efficiently collecting submicron particles in a fluid containing particles such as exhaust gas, and detoxifying the collected particulates by oxidative combustion. is there.

[0006]

According to the structure of the present invention, the fine particle-containing fluid that has flowed into the device from the intake is accelerated and swirled to form a high-speed swirl flow, and the centrifugal force acting on this high-speed swirl flow is provided. In the particle separation device in which the particles in the fluid are centrifugally separated due to the difference in specific gravity from the fluid, and the fluid after particle separation is discharged from the discharge port, in the flow path in which the particle-containing fluid moves while swirling at high speed, A metal cylindrical electrode made of a multi-cylinder having a large number of through holes formed therein, and a rod-shaped electrode that is inserted into the cylindrical electrode and has a large number of needle-shaped electrode portions protruding therefrom are provided. A direct current voltage is applied between them to form an electrostatic field, and a combustion unit for burning the fine particles separated from the fluid is formed in the space between the multiple cylinders of the cylindrical electrode. To do.

The metal cylindrical electrode is formed of a mesh tube, a punched metal formed into a cylindrical shape, a wire knitted into a cylindrical shape, or a porous cylinder formed by incomplete sintering or the like. There is.

The combustion section is filled with a mixture of catalyst fibers having glass fibers as a carrier and metal fibers in a space between multiple cylinders, or is wound with a catalyst fiber network and a metal fiber network having glass fibers as a carrier. It is formed by inserting a metal fiber without a catalyst or by inserting a metal fiber net without a catalyst or by inserting a metal fiber network without a catalyst.

Further, according to the present invention, the fine particle-containing fluid that has flowed into the apparatus from the intake is accelerated and swirled to form a high-speed swirl flow, and the fine particles in the fluid are generated by the centrifugal force acting on the high-speed swirl flow. In a fine particle separation device in which the fluid after being separated by fine particles is discharged from an outlet by centrifugal separation due to the difference in specific gravity with the fluid, the flow path in which the fine particle-containing fluid moves while swirling at high speed is composed of one cylindrical porous forming electrode. A metal cylindrical electrode and a rod-shaped electrode that is inserted into the cylindrical electrode and has a large number of needle-shaped electrode portions projecting therefrom are provided, and a DC voltage is applied between them to form an electrostatic field. It may be one that has been.

[0010]

The fine particle-containing fluid is accelerated and swirled in the device to be a high-speed swirling flow. Due to the centrifugal force acting on this high-speed swirling flow, the fine particles in the fluid are centrifugally separated due to the difference in specific gravity with the fluid. At this time, the fine particles in the fluid are applied with a DC voltage between the metal cylindrical electrode and the rod-shaped electrode that is inserted into the cylindrical electrode and has a large number of needle-shaped electrode portions projecting therefrom. The formed electrostatic field charges and aggregates into large particles, which facilitates centrifugation.

The fine particles that have been centrifugally separated and jumped to the outer peripheral side reach the combustion portion formed in the space between the multiple cylinders of the cylindrical electrode, where they are oxidatively burned and rendered harmless. The combustion part is formed in a structure in which fine particles are easily retained. It is desirable that the combustion section has a catalyst that oxidizes and combusts the fine particles, but even if it is not, the fine particles spontaneously combust with the charged oxygen by the heat energy of the exhaust gas of the engine. When the metal cylindrical electrode is composed of one cylindrical porous electrode, it oxidizes and combusts in the pores of the electrode.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front sectional view of the particulate separation device, FIG. 2 is a sectional view of a nozzle pipe portion, and FIG. 3 is a sectional view of a diffuser pipe portion.

In FIG. 1, a nozzle tube 2 is attached to one end of an elongated cylindrical case 1. The nozzle tube 2 (see FIG. 2) is composed of a straight part 2a having an inlet 3 opened at the tip and a circular case part 2b continuous with the straight part 2a. The circular case part 2b has a blade 4 connected between its end faces. A plurality of sheets are provided separately on the same circumference having a diameter smaller than the inner diameter of the case portion 2b. These blades 4 are rectangular plates, and the space between adjacent blades 4 constitutes the nozzle portion 5 such that the cross-sectional area thereof gradually decreases inward in the radial direction, and The fluid that has passed through is arranged so as to generate a swirling flow in the circumferential direction. A central space 6 surrounded by the blades 4 of the circular case 2b is concentrically connected to the elongated cylindrical case 1 for communication.

A diffuser pipe 7 is attached to the other end of the cylindrical case 1. The structure of the diffuser pipe 7 is the same as that of the nozzle pipe 2 (see FIG. 2) as shown in FIG. That is, 7a is a straight line portion, 7b is a continuous circular case portion, 8 is an outlet opening at the tip of the straight line portion 7a, and 9 is a blade made of a rectangular plate connected between the end faces of the circular case portion 7b. A plurality of spaced apart portions are provided on the same circumference having a diameter smaller than the inner diameter of the portion 7b, and the cross-sectional area of the space portion between the adjacent blades 9 is gradually increased outward in the radial direction so that the diffuser portion is formed. Make up 10. Reference numeral 11 denotes a central space portion surrounded by the blades 9 of the circular case portion 7b, which is concentrically connected to and connected to the cylindrical case 1.

A rod-shaped electrode 12 is arranged along the axis in the elongated cylindrical case 1. The rod-shaped electrode 12 is formed by arranging a large number of needle-shaped electrode portions 14 radially outwardly protruding on a shaft body 13 arranged along the axial center at intervals in the longitudinal direction. .. A cylindrical electrode 15 is concentrically provided in the cylindrical case 1. Cylindrical electrode 1
Reference numeral 5 denotes a cylindrical body having a double cylinder structure composed of an inner cylinder 16 and an outer cylinder 17. Both the inner and outer cylinders 16 and 17 are formed of mesh-shaped stainless steel pipes, and a large number of through holes are formed in the thickness direction. Has been done. The cylindrical space formed by the inner and outer cylinders 16 and 17 is filled with a mixture of a catalyst fiber having glass fiber as a carrier and a metal fiber, and forms a combustion portion 18. The inner cylinder 16 has the same diameter as the outlet space 6 of the nozzle tube 2 and is arranged concentrically.

The inner and outer cylinders 16 and 17 are made of mesh-shaped stainless steel pipe, but the invention is not limited to this. For example, a punched metal is made into a cylindrical shape, or a stainless wire rod is knitted into a cylindrical shape. Use the one that you made. A metal double cylinder having a large number of through holes in the thickness direction may be used. The material is not limited to stainless steel,
Other metals may be used.

The cylindrical space formed between the inner circumference of the cylindrical case 1 and the outer circumference of the cylindrical electrode 15 is the cylindrical electrode 1
5 and the needle-shaped electrode portion 14 of the rod-shaped electrode 12 constitute an air reservoir 19 for supplying oxygen to the electrostatic field. The air reservoir 19 is communicated with the diffuser pipe 7 through a through hole 20 formed in the end surface of the diffuser pipe 7.

Both ends of the shaft body 13 of the rod electrode 12 are fixed to shaft rods 21 and 22, respectively, and one shaft rod 21 penetrates the circular case portion 2b of the nozzle tube 2 and communicates with the outside of the circular case portion 2b. The connected bottomed cylindrical member 23 is fixed so as to project from the end face, and the other shaft rod 22 is the diffuser pipe 7.
It is fixed by protruding from the end surface of the bottomed cylindrical member 24 that penetrates the circular case portion 7b and is connected to the outside of the circular case portion 7b.

A high voltage DC power supply (10 to 20 KV)
25 is connected between the tubular electrode 15 and the protruding end portion of one shaft rod 21 of the rod electrode 12, and the tubular electrode 15 and the rod electrode 1 are connected to each other.
A high DC voltage is applied between the cylindrical electrode 15 and the needle-shaped electrode portion 14, and a high-voltage electrostatic field is formed between the cylindrical electrode 15 and the needle-shaped electrode portion 14. Usually, the rod-shaped electrode 12 (needle-shaped electrode portion 14) is used as the cathode and the cylindrical electrode 15 is used as the anode, but the reverse case is also possible. By making the center electrode needle-shaped and the outer electrode cylindrically shaped to have an unequal electric field, a high voltage is locally generated even at a relatively low voltage, and corona discharge is likely to occur.

A flow rate adjusting valve 26 is provided in a central space 6 surrounded by the blades 4 of the circular case 2b of the nozzle tube 2, and automatically moves in the axial direction according to the degree of load to automatically adjust the flow rate. It is configured to adjust.

A flow rate adjusting valve 27 is provided in a central space 11 surrounded by the blades 9 of the circular case portion 7b of the diffuser pipe 7 and is automatically moved in the axial direction according to the degree of load to automatically adjust the flow rate. It is configured to adjust.

It is also possible to assemble a plurality of the apparatus in one set so that heat is exchanged with the cooling fluid flowing through the spaces between the plurality of apparatuses.

The operation will be described below. The fine particle-containing fluid that has flowed into the apparatus from the intake port 3 of the nozzle tube 2 is accelerated through the nozzle portion 5 of the nozzle tube 2 and a swirl flow is generated, and this high-speed swirl flow enters the cylindrical case 1. .. Since a high-voltage electrostatic field is formed between the cylindrical electrode 15 and the needle-shaped electrode portion 14 in the cylindrical case 1, the particles in the fluid are charged by the corona discharge and aggregate to become larger particles, Fine particles can be easily separated by centrifugal force. Cylindrical electrode 1
Since a large outstanding centrifugal force acts on the fine particle-containing fluid that moves while swirling in 5 at high speed, the fine particles in the fluid jump out to the outer peripheral side due to the difference in specific gravity between the fluid and the cylindrical electrode 15
Enter the inner and outer cylinders 16 and 17 that constitute the. Then, the fine particles oxidize and burn in the burning portion 18 in the cylindrical electrode 15, and the organic extract called SOF of the particulates is well oxidized to become mainly carbon dioxide gas. A heater may be provided to completely oxidize the carbonaceous dry suit.

As described above, the fluid from which the fine particles are separated is decelerated by the diffuser portion 10 of the diffuser pipe 7, the pressure is recovered, and the fluid is discharged from the discharge port 8 of the diffuser pipe 7.

Needless to say, the present invention is not limited to what has been described in the above embodiments, and various modifications can be made without departing from the spirit of the invention.

For example, a porous cylinder electrode formed by incomplete sintering or the like can be used as the double cylinder forming the cylindrical electrode.

In the burning section, a cylindrical one in which a catalyst fiber network having a glass fiber carrier and a metal fiber network are alternately wound is inserted in the space between the inner and outer cylinders of the cylindrical electrode, or the catalyst is inserted. It may be formed by filling the removed metal fibers or inserting a metal fiber network excluding the catalyst.

The cylindrical electrode is not limited to the double cylinder, but may be a multiple cylinder.

In the case of a porous molded cylindrical electrode formed by incomplete sintering or the like, the cylindrical electrode may be composed of one porous molded cylinder.

Although the fine particle-containing fluid is configured to impart the speed-up and swirl simultaneously with the nozzle tube, the speed-up part and the swirl part may be provided separately.

[0031]

As described above, according to the present invention, a high-voltage electrostatic field is formed between the rod electrode and the cylindrical electrode, and the fine particles in the fluid passing through the electrostatic field are charged and aggregated. The fine particles in the fine particle-containing fluid that moves while swirling at high speed can be easily centrifuged. Then, the centrifugally separated fine particles are oxidized and burned in the burning portion of the cylindrical electrode to be rendered harmless. If this is applied to an automobile, fine particles in exhaust gas discharged from an internal combustion engine can be removed, which is preferable, and EGR can be used for a diesel engine.

[Brief description of drawings]

FIG. 1 is a front sectional view of a particle separation device.

FIG. 2 is a sectional view of a nozzle tube portion.

FIG. 3 is a sectional view of a diffuser pipe portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical case 2 Nozzle tube 3 Inlet 4, 9 Blade 5 Nozzle part 6, 11 Space part 7 Diffuser pipe 8 Discharge port 10 Diffuser part 12 Rod-shaped electrode 13 Shaft body 14 Needle-shaped electrode part 15 Cylindrical electrode 16 Inner cylinder 17 Outside Cylinder 18 Combustion part 19 Air reservoir 20 Through hole 21, 22 Shaft rod 23, 24 Bottomed cylindrical member 25 DC high-voltage power supply 26, 27 Flow control valve

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B03C 3/00 J 8925-4D B04C 3/00 Z 6953-4D 9/00 6953-4D F01N 3 / 02 301 E A 311 F G

Claims (6)

[Claims] 1. A fine particle-containing fluid that has flowed into the apparatus through an intake is accelerated and swirled to form a high-speed swirl flow, and the centrifugal force acting on the high-speed swirl flow causes the specific gravity of the fine particles in the fluid to be higher than that of the fluid. In a fine particle separation device in which a fluid after being separated by fine particles is discharged from an outlet by a difference, a large number of through holes are formed in a thickness direction in a flow path in which the fine particle-containing fluid moves while swirling at high speed A metal cylindrical electrode composed of multiple cylinders and a rod-shaped electrode that is inserted into the cylindrical electrode and has a large number of needle-shaped electrode portions protruding therefrom are provided, and a DC voltage is applied between them. A particle separation device, wherein an electrostatic field is formed, and a combustion unit for combusting particles separated from the fluid is formed in a space between multiple cylinders of the cylindrical electrode. 2. The metal tubular electrode is a mesh tube,
The particulate separation device according to claim 1, wherein the punched metal is formed in a cylindrical shape, a wire rod is knitted into a cylindrical shape, or a porous cylinder formed by incomplete sintering or the like. 3. The combustion unit is formed by filling a mixture of catalyst fibers having glass fibers as a carrier and metal fibers in a space between multiple cylinders. Fine particle separator. 4. The combustion section is formed by inserting a winding of a catalyst fiber network having glass fibers as a carrier and a metal fiber network into the space between the multiple cylinders. The particulate separation device described. 5. The fine particle separation device according to claim 1, wherein the combustion section is formed by filling a metal fiber in a space between multiple cylinders or inserting a metal fiber network. 6. The fine particle-containing fluid that has flowed into the device from the intake is accelerated and swirled to form a high-speed swirl flow, and the centrifugal force acting on the high-speed swirl flow causes the fine particles in the fluid to have a specific gravity with the fluid. In a fine particle separation device in which a fluid after fine particle separation is discharged from an outlet by centrifugal separation due to a difference, in a flow path in which the fine particle-containing fluid moves while swirling at high speed, a cylindrical metal tube made of one cylindrical porous forming electrode An electrode and a rod-shaped electrode that is inserted into the cylindrical electrode and has a large number of needle-shaped electrode portions projecting therefrom are provided, and a DC voltage is applied between them to form an electrostatic field. A fine particle separator.