JPS6056527B2 - dust collector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates more particularly to dust collection technology and to a new and improved apparatus of the electrostatic precipitation type for separating particulate matter from a gas stream.

Electrostatic precipitation type dust collection methods and devices are known and have the advantage of being able to handle relatively large loads (large amounts of dust) with low pressure drops within the device.

However, electrostatic precipitators or collectors (Elec-TrOst)
The problem is that dust can pass through momentarily due to arcing or similar electrical problems. Dust collection methods and devices are also known that employ mechanical filtration using porous filter materials such as textile filters or baghouses, in which case the operator is not exposed to large amounts of dust and is therefore safe. can effectively collect fine particles (dust).

However, the ability of this mechanical filtration method is limited and difficult to use, as dust can pass through the filter material if the filter material has small pores or is relatively porous. The types of filter materials that can be used are limited, and the equipment is expensive to manufacture. Furthermore, in order to obtain good effectiveness with mechanical filters of this type, it is often necessary to remove dust deposited on the filter material. It is therefore an object of the present invention to provide a new and improved apparatus which effectively combines various advantageous features of electrostatic precipitation and mechanical filtration.

Another object of the present invention is to provide an apparatus capable of achieving effects superior to those achieved by either electrostatic precipitation or mechanical filtration alone.

The present invention is an apparatus for separating particulate matter from a gas stream, in which contaminated gas is passed through an electrostatic precipitator to remove most of the particulate matter, and the gas is then passed through an electrostatic precipitator to remove the majority of the particulate matter. The material is passed through a filter to remove any remaining particulate matter.

The precipitator and filter are arranged concentrically such that gas is forced to flow axially along the precipitator and radially outwardly to the filter. The present invention will be described in detail below with reference to illustrated embodiments.

Referring to FIG. 1, the apparatus of the present invention for separating particulate matter from a gas stream includes an inlet 11 for receiving contaminated gas.
and an outlet 12 for discharging purified gas from the device.

Although housing 10 is shown schematically for convenience of illustration, the preferred form of the housing will be described in detail below. Gas is forced to flow through the device from the inlet 11 to the outlet 12 by a fan 7 driven by a motor 8 and connected to the outlet 12. The outlet of the fan 7 is connected to an exhaust duct 9 through which the purified gas is conveyed. It consists of an electrostatic precipitator or collector 14 with a connected inlet.

The precipitator 14, which is arranged vertically within the housing 10, is cylindrical. Gas flows generally axially through the precipitator and exits the precipitator generally radially outwardly. Precipitator 14
includes a cylindrical collecting structure having an opening at one end thereof defining an inlet and an outlet spaced axially from the inlet.

This collection structure includes a cylindrical screen 18 of conductive material;
It consists of an electric wire 19 connected to apply a potential to this screen as described later. The screen 18 is fixed at one end to the first disc-shaped end member 20 of the precipitator 14 and at the other end to the second ring-shaped end member 2 of the precipitator.
It is fixed at 2. The central hole of this end member 22 defines the inlet of the precipitator 14, as shown in FIG. The screen 18 is made of stainless steel mesh with a wire spacing of approximately 112 inches, and the end members 20,
Preferably, 22 is made of a dielectric material such as polyester laminate. In the center of the collection structure, there is a long and thin corona electrode 2.
4 will be deployed.

This corona electrode is made of a relatively thin wire (preferably stainless steel), and one end thereof is fixed to a connecting member 25 which is inserted through a hole provided in the end member 20 and supported. The other end of electrode 24 projects from end member 20, thereby allowing electrical connection of electrode 24 to the outside. An adjustment mechanism including a compression spring 26, a washer 27, and a lock nut 28 is provided at the outer end of the connecting member 25 to adjust the tension of the electrode 24. A conductor 29 is connected to the outer end of the connecting member 25 in order to make an electrical connection with the electrode 24 as described below. The other end of the corona electrode 24 is inserted into a hole provided in a dielectric rod 30 (FIG. 4), and a stop member 31 for holding it on the rod 30 is attached to the tip of the electrode 24.

That is, after the tip of the electrode 24 is inserted into the hole of the rod 30, a steel button 31 is fixed to the tip of the electrode 24 with silver solder, and this button comes into contact with the rod 30 to hold the electrode 24 in a predetermined position. . Both ends of the rod 30 pass through holes drilled in a first ring 32 fixed to an annular groove provided on the outer surface (lower surface in FIG. 4) of the end member 22.

A second ring 33 having a diameter larger than that of the first ring 32 is secured in another annular groove cut into the outer surface of the end member 22. The annular space between the two rings 32 and 33 is filled with R, which is available from General Electric Company.
A resin filler 34 such as TV-60 is filled in advance. This resin, when cured, secures the rod 30 in place.
The end member 22 is provided with a peripheral surface 35 that is inclined outwardly at a certain angle with respect to the axis of the corona electrode 24 .

In other words, the circumferential surface 35 forms an obtuse angle with respect to the lower surface of the end member 22 and an acute angle with respect to its upper surface. The diameter of the top surface of end member 22 is therefore slightly larger than the diameter of the bottom surface. The reason why the peripheral surface 35 of the end member 22 is sloped will be described later. Screen 18 of precipitator 14 has an axial working length substantially equal to the axial working length of corona electrode 24 . Preferably, this electrode 24 is disposed along the long axis of the screen 18. Precipitator 14 includes an impermeable tube or sleeve 37 that closely surrounds screen 18. This sleeve 37 is the screen 18
is of sufficient length to extend along most of its axial length. The purpose will be explained later. Sleeve 37 can be made of either a conductive material or a dielectric material.

For example, when constructed as a working unit, the screen 18 has a length of approximately 226 cm (89 inches) and an outer diameter of approximately 1 inch.
1 cm (4 inches 7132) and sleeve 37
is approximately 191 cm (approximately 75 inches) long, and the corona electrode 24 is approximately 228 cm (approximately 89 inches) long. The apparatus of the invention further includes a porous dielectric filter 40 disposed within the housing 10 between the precipitator 14 and the clean gas outlet 12. This filter 4
0 is preferably in the form of a thin-walled tube or sleeve, which surrounds the precipitator and is spaced and concentric with respect to the screen 18. The filter 40 may be comprised of various porous derivatives such as woven, knitted or non-woven fabrics, permeable membranes, fibrous materials and porous plastics or other relatively hard porous materials. A fabric that satisfactorily functions as the filter 40 is DuPont's Nomex Filter Media (NOmexFilterMe-D).
ia) There is a product named Style #1610. If the filter 40 is made of fabric, a gas flow of about 5.4 cubic meters (200 cubic feet) per minute through a fabric area of about 90 square centimeters (1 square foot) will occur within the station.
．． It was found that the porosity or air/fabric ratio should be such as to provide a pressure drop of 7 millimeters (112 inches) of water.

If nonwoven materials are used, they need to have relatively high porosity. The device of the present invention further includes means for applying an electric field to the filter 40. As shown in FIGS. 1 and 4, the distance between the conductive materials, preferably wires, is approximately 1.77 mm.
A screen or cage 45 made of approximately 112 inch stainless steel mesh is located between the filter gate 40 and the clean gas outlet 12. This cage 4
5 has a cylindrical shape and surrounds the filter 40 over its entire length in the axial direction. Since the cage 45 is located close to the filter 40, the precipitator 14 and the filter 4
The interval 0 is wider than the interval between the filter 40 and the cage 45. That is, the diameter of the cage 45 is slightly larger than the diameter of the filter 40 and the filter 40 is not placed as close to the screen 18 of the precipitator 14. An example manufactured as an actual working unit includes a tubular filter 40 with a length of approximately 249 cm (approximately ? inches) and an inner diameter of approximately 15 cm (approximately 6 inches), and a length of approximately 244 CTfL (approximately 96 inches) and an outer diameter. is about 1
80 (approximately 7 inches 114) cage 45.

As mentioned above, in this operational unit, the outer diameter of the screen 18 is about 11 cm. This dimensional relationship is maintained to ensure proper electrical operation of the device as will be described in detail below. Electrical wire 47 is connected to cage 45 and is adapted to apply an electrical potential to the cage as described below.

6-8 illustrate the preferred construction of the housing 10 of the device of the present invention. Housing 10 shown in these drawings
has a module configuration including a plurality of (four in this embodiment) dust collector groups or modules, and each module includes six dust collector units 48. Of course, each unit 48 is comprised of a combination of an electrostatic precipitator 14, a filter 40, and a screen or cage 45. These units are arranged vertically, and in this embodiment, each module includes two rows of three units, for a total of six units.

These modules are arranged side by side along one vertical sidewall 50 of housing 10 between end walls 52 and 54. Each module is separated from adjacent modules by spaced vertical partition walls 55. Housing 1
The other side wall 56 of 0 is remote from the dust collection module;
It has a contaminated gas inlet 11 and a clean gas outlet 12.
The precipitator unit is supported within the housing 10 in the following manner.

A base or support member 60 is fixed in a suitable manner within the housing 10 near its bottom and spaced from the bottom wall. The support member 60 is attached to both side walls 52 and 54 of the housing 10.
There is a bridge extending between the two, which supports all of the precipitator units. The support member 60 is provided with one hole for each dust collection unit, through which contaminated gas flows into the precipitator 14 of the corresponding unit.
It's on.

As shown in FIG. 4, the hole 62 is surrounded by a support and seal mechanism.

This support/sealing mechanism includes a first ring 63 having a diameter slightly larger than the diameter of the hole 62 and fixed to the support member 60 by tack welding or the like, and a first ring 63 surrounding the first ring 63. the first ring 6
3, and a second ring 64 having an axial length (height) longer than the axial length (height) of No. 3. The second ring 64 is also fixed to the support member 60 by tack welding or the like, and has a groove 66 formed in its outer peripheral surface. The purpose of this groove will be explained later. ) In the illustrated example mechanism including four modules, each module includes six precipitator units, for a total of 24 units, so the support member 60 has 24 holes 62; 24 ring mechanisms each consisting of two rings 63 and 64 are provided.

Each dust collector unit has its bottom supported by a support member 6 as follows.
Supported by 0.

The cage 45 of each unit has an inner diameter larger than the outer diameter of the ring 64 and is placed on the support member 60 so as to surround the hole 62 . Cage 45 has sufficient rigidity to support the entire unit, as will be explained next. The filter 40 is fitted relatively tightly into the ring 64, and the tightening ring 67 is fitted tightly into the groove 66 of the ring 64 from the outer periphery of the filter 40.

This provides a substantially airtight seal between the end of filter 40 and ring 64. Inner ring 63 fits slightly into filler 34 between rings 32 and 33.
This places the central hole in the insulating member 22 in communication with the hole 62 to receive incoming contaminant gas and establish a fluid-tight seal between the ring 63 and the filler 34. The bottom of the precipitator 14, including the insulating member 22, is supported by a ring 63. Each precipitator unit is thus supported at its bottom by a support member 60. Each precipitator unit includes a tensioning mechanism 80. This mechanism 80 is supported by cage 45 and connected near the top of filter 40 (see FIG. 4). The filter 40 has a precipitator 1 at its bottom.
4 as a means for engaging the bottom of the filter 40 so that the tension applied to the filter 40 is also applied to the precipitator 14. The apparatus of the present invention also includes a tube or sleeve 84, one end of which is secured to the insulating member 20 and the other end of which is secured to limit or prevent movement of the precipitation device 14 when tension is applied thereto. There is. The tensioning mechanism 80 has a closure cap 86 having a flat plate 87 and an annular flange 88 depending therefrom. This cap 86 is placed on and supported by the cage 45 and constitutes the upper part of each dust collector unit. A ring-shaped connecting member 89 having an outer diameter smaller than the inner diameter of the flange 88 and having two annular flange portions at right angles to each other connects the filter 40 to the cap 86 . That is, the upper end of the filter 40 is fastened to a connecting member 89 by a fastening member 90, and the connecting member 89 is fixed to the flat plate 87 of the cap 86 by a suitable fastening means 92. A second connecting member 94 having a similar shape to the connecting member 89 is fixed to the filter 40 within the filter 40 by a clamp 96 slightly below the upper end thereof. The second connecting member 94 is supported by a bolt 97 that extends through the second connecting member 94, the first connecting member 89, and the cap 86. A compression spring 99, a washer 100, and a nut 101 are equipped at the tip of a bolt 97 that protrudes outward beyond the cap 86. Three supporting means, each including a bolt, a compression spring, a washer, and a nut, are disposed around the sleeve 84 as shown in FIG. Spring 99 applies tension to fibrous filter 40 and pulls it toward cap 86 . This tension can be adjusted from the outside by simply turning the nut 101 to adjust the compression of the spring 99. When the filter 40 is pulled taut toward the cap 86, the engagement between the bead 82 and the sloped surface 35 of the insulating member 22 pulls the precipitator 14 upward (see FIG. 4). This upward movement of the precipitator 14 is restricted by a sleeve 84 interposed between the insulating member 20 and the cap 86. The bead 82 near the lower end of the filter 40 can be made by wrapping a wire loop or ring 103 into a folded strip of fabric 104 and sewing it to the inner surface of the filter 40, as shown in FIG.

When filter 40 is pulled taut, bead 82 acts as a wedge-like member that engages snugly against circumferential surface 35 of insulating member 22 .

This transmits tension to the precipitator 14 to create a substantially fluid-tight seal between the filter 40 and the insulating member 22, preventing gas from escaping between the two.
The sleeve 84 not only connects the filter 40 but also connects the connecting member 8.
The diameter is large enough to allow it to be placed inside 9 and 94.

Sleeve 84 is of a length to fit snugly between insulating member 20 (which is actually somewhat embedded) and closure cap 86. A tensioning mechanism similar to that described above is provided in each precipitator unit shown in FIGS. 6-8. Each cap 86 is provided with a hollow boss or projection 105.

This boss 105 mechanically connects each unit to a vibrating means 108, as shown in FIG. 6, so that the units can be vibrated for cleaning. That is,
The vibration means 108 is of the type operated by compressed air;
The approximately horizontal vibrations are transmitted to each precipitator unit via the connecting rod 109. Rod 109 is vibration means 108
The cap 86 extends from the cap 86 and is engaged with and received by the boss 105 of each cap 86 . A supply pipe 110 connects the vibrating means 108 to a source of compressed air (not shown). One vibration means 108 is provided for each module consisting of six units.

Therefore, in the configuration shown in FIGS. 6 to 8, there are a total of four vibration means 1.
08 is required. In this case, six dust collector units of each module can be vibrated simultaneously. The device of the invention furthermore includes means for controlling the flow of gas through the precipitator unit, in particular when vibrating the precipitator unit for removing the collected dust, the gas flow from this unit to the clean gas outlet 12. including means for stopping the flow gate.

According to a preferred embodiment of the invention, the gas flow through the several precipitator units of each module is controlled by a single device, and the control of each of the several modules is performed separately and independently. It will be done. Referring first to FIG. 6, spaced vertical partition walls 55 meet in a communication section having passageways or chambers communicating each module with a common outlet 12. Referring first to FIG.

It includes spaced apart vertical walls 115 parallel to the sidewalls 56 of the juncture housing. The edge of the partition wall 55 is joined to the side wall 56 of the housing. 1st
A horizontal wall 116 connects the vertical wall 115 below the outlet 12 to the side wall 56 of the housing. This results in a chamber or passage connecting all modules to the outlet 12 in the side wall 5.
6, defined by vertical walls 115 and horizontal walls 116; A second horizontal wall 117 is above the inlet 11 and the outlet 12
is connected to the side wall 56 of the housing below, thereby forming a common connection or chamber between the inlet 11 and the inlet of each precipitator unit.

Each module of the precipitator unit is normally in communication with the outlet 12, thus allowing flow of purified gas from the precipitator to the outlet 12.

This flow of gas is selectively and separately blocked between each module and the outlet 12 by damper means provided in each module. Referring to FIGS. 6 and 7, each module has a generally horizontally disposed damper 120 which is vertically oriented by a piston rod 123 of an air cylinder 122 mounted at the top of the housing 10. Moved.

The upward movement of the damper 120 may be limited by a suitable stop member (not shown) mounted on the upper wall of the housing 10 and projecting downwardly therefrom. The downward movement of damper member 120 is controlled by walls 56, 115 and vertical flanges 126, 127 attached to partition wall 55.
limited by. Such flanges 126, 12
7 is a dust collector. Each module of the knit defines a rectangular opening connecting each module to a common path to the outlet 12.

When the damper 120 is lowered and placed on the upper edges of the flanges 126, 127, the corresponding module is closed, thereby! outlet 12 from that particular precipitator module.
This prevents gas from escaping. At the bottom of the housing 10, sloped side walls 130, 132 form a hopper.

When the dust collector unit is vibrated, the collected dust falls into this dust collector. Dust is removed from the hopper using a screw conveyor (not shown) installed inside the hopper.
This can be easily done by The screw conveyor is mounted in the housing 10 and is driven by a motor 134 connected to the conveyor via a suitable transmission 136 to convey the dust in the hopper to one end thereof.
At one end of the hopper an outlet is provided at the bottom of the hopper, the outlet being either a Bladder type or a Razzer type valve providing a vacuum seal.
evalve) 137.

That is, the hopper is normally closed, but when the weight of accumulated dust becomes large enough, the valve 137 is opened and the dust inside the hopper is discharged into a suitable container, and this container is used to remove the dust from the equipment. except. A power source 138 is located below the housing.

As this power source, a commercially available power supply for electrostatic precipitators having a maximum output voltage of 50,000 volts can be used. The device of the invention operates as follows.

Here, we will explain the operation of the single unit shown in Figures 1 to 5, but it should be understood that similar operations are performed in each of the multiple units shown in Figures 6 to 8. Good morning. With reference to FIGS. 1 and 4, while contaminated gas is introduced into the apparatus via inlet 11 and sent through precipitator 14 by rotation of fan 7, a large portion of this gas flow is removed. of particulate matter is collected.

That is, the gas to be purified enters the precipitator 14 from the bottom through the holes 62 in the support plate 60 and flows axially through the precipitator along the length of the sleeve 37. This gas then flows generally radially outwardly through the screen 18. In this embodiment, corona electrode 24 is held at a relatively negative voltage.

That is, the electrode 24 is grounded. Screen 18 is then connected to a relatively positive voltage. That is,
Conductor 19 is connected to the positive terminal of a power source, such as power source 138 of FIGS. 6-8, and conductor 29, shown in FIG. 4, is connected to housing 10. The magnitude of the applied potential is determined by the size of the precipitator unit. screen 1
For a typical unit with a diameter of about 10 cwL (about 4 inches), the potential difference is typically about 30,000 volts. Although the polarities of the corona electrode 24 and the screen 18 can be switched, it is preferable that the corona electrode 24 be at a relatively negative potential.

This is because a more stable corona can be generated with a relatively large current and more effective dust collection can be performed. A portion consisting of the corona electrode 2, the sleeve 37, and the screen 18 constitutes a substantially cylindrical concentric electrostatic precipitator.

Dust and other particles entering this device. The fine particulate matter is charged by a corona current of several milliamps and passes through the screen 1.
It is collected on 8. Sleeve 37 guides the flow of gas and dust over substantially the entire length of screen 18 to enhance dust collection. Sleeve 37 can be made of either a conductive material or a dielectric material. Most of the dust in the gas stream, up to about 95%, is collected in the precipitator.

Gas is conveyed from the precipitator by a fan 7 through a filter 40 of porous material. This filter 40
An electric field is applied to. That is, the gas is transferred to the precipitator 1
4 through screen 18 and enters the space between screen 18 and filter 40 where it is exposed to the electric field between screen 18 and screen 45. The potential difference between screens 45 and 18 is typically the same as the potential difference between corona electrode 24 and screen 18. A conductor 47 shown in FIGS. 1 and 4 is connected to the housing 10. The strength of the electric field can be increased or decreased as needed. Filter 40 serves to remove residual dust from the gas stream. The gas purified in this way is sucked out of the filter 40 by a fan and is carried out at the outlet 12.
is discharged from the device through. In the illustrated embodiment,
Although gas is forced through the device by a fan 7 at the outlet 12, it is also possible to force the gas through the device by a fan at the inlet 11. Filter 40 made of porous dielectric material
provides a physical matrix for dust collection and helps achieve local concentration of the electrostatic field through the dielectric properties of the filter material.

Since the filter 40 is placed in this electrostatic field,
There is an interaction between the electrostatic field and the dielectric structure, e.g. the dielectric fibers in the case of woven filter materials, which strengthens the electric field and creates local concentrations that trap the charged dust in the precipitator. act. As a result, the apparatus of the present invention has a precipitator 1
A better dust collection effect than that achieved by filter 4 alone or filter 40 alone can be achieved. This is evidenced by the fact that it has been found that it is not necessary to collect a layer of dust on the filter 40 to create a filter cake in order to obtain excellent results. Furthermore, small pores in the material of the filter 40, such as a fabric or fabric, which would normally allow dust to escape, are unaffected by the present invention when the filter means is placed in an electrostatic field.

Another important advantage provided by the method and apparatus of the present invention is that there is no problem of dust leakage through the filter material due to the effect of electrostatic fields on the filter 40, which is better than what could be used hitherto. More porous materials can be used as filter 40. It is important that the filter 40 be placed close to the cage 45.

In this embodiment, the filter 40 is tubular or sleeve-shaped and has approximately the same diameter as the cage 45.
The screen 18 or sleeve 37 of the precipitator 14 is not very close. In other words, the distance from the precipitator 14 to the filter 40 needs to be longer than the distance between the filter 40 and the cage 45. If this distance relationship is not maintained and the filter 40 is placed close to the positive potential of the screen 18 or the sleeve 37, a reverse corona effect will occur as a result of the electric field concentration generated by the filter 40, which will cause the corona electrode to An arc is generated in the space between 24 and cage 45. After the dust collector has been operated for a period of time, the corona electrode screens 18, 45 and the filter 40 become covered with dust and other particulate matter trapped from the gas flow and must be cleaned. . This cleaning involves cutting off the flow of gas through the device and vibrating the device to cause the trapped dust to fall out of the hole 62, and this dust is collected by a suitable means such as a hopper and removed from the device. This can be done by As shown in Figure 4, the sleeve 3
Due to the annular space between the lower end 7 and the upper surface of the end member 22, dust removed from the surface of the filter 40 can fall from this space through the hole 62.

There is no need to reverse air flow for this cleaning, and there is an advantage that cleaning can be performed even while the device is maintained in an energized state. However, if desired, backflow air may be used and the power supply may be interrupted during cleaning, although these operations are not necessary for effective operation. In systems having multiple units, such as those shown in FIGS. 6-8, the cleaning operation is performed separately and independently for each group or module of precipitator units.

The cylinder 122 of the particular module to be cleaned is actuated to lower the plate or damper 120 to interrupt the flow of gas through the particular module, and the vibration means 108 of that module is actuated to cause the six of the modules to be cleaned. All units vibrate at the same time. When this operation is completed, the cylinder 122 is operated and the damper 1
20 and put the module back into operation.

If desired, subsequent modules can be cleaned in a similar manner. As shown in FIG. 6, removable bars 1 are provided on the top surface and side wall 50 of the housing 10
40, 142, the unit can be lowered into position within the housing 10 and maintenance work can be performed if necessary. From the foregoing, it is clear that the present invention achieves its intended purpose.

The method and apparatus of the present invention provide a desirable combination of the characteristics of electrostatic precipitation dust collection with the characteristics of mechanical filtration using porous filter materials such as fibrous filters or baghouses. be. As in the case of electrostatic precipitators, large amounts of dust can be handled due to the low pressure drop within the device, and as in the case of baghouses, the operator can handle large amounts of dust. It can very effectively collect small dust particles without the risk of being exposed to air. Furthermore, the method and apparatus of the present invention can provide results that are superior to those achieved by either electrostatic precipitation or mechanical filtration alone. Ru.

In typical operation of the apparatus of the present invention, the dust load is approximately 10-20 grains per cubic foot.
rcubicfOOt) air/cloth ratio (Air/ClO
thratiO) is, for example, 20 to 30 if the filter 40 is made of cloth or fabric, and the pressure drop within the device is about 7.6 C77 water columns! (approximately 3 inches) and has an efficiency of 99% or more.

The combination of an electrostatic precipitator and a filter means consisting of a porous dielectric material to which an electrostatic field is applied provides several desirable effects.

That is, the dust collection action is very effective due to the action of electrostatic forces combined with the construction of the filter means, such as the fabric or fibers of the fabric. Highly porous filter materials can be used, and even if the filter material has pores, it will have little effect. Filter 40 serves to capture dust that has passed through the precipitator due to arcing or similar electrical problems. The device of the invention can be easily adapted in a modular manner. In this way, each unit can be easily replaced or combined into modular sections. Any number of such sections may be provided to provide the required capacity for a particular device. Maintenance of the device is relatively easy because the cartridge or unit can be adjusted on its top.

[Brief explanation of the drawing]

FIG. 1 is an elevational view showing a main part of an embodiment of the present invention in longitudinal section. Figure 2 is a plan view taken from line 2-2 in Figure 1, Figure 3 is an enlarged sectional view taken from line 3-3 in Figure 1, and Figure 4 shows the main parts of the device in Figure 1. 5 is an enlarged vertical sectional view of a part of FIG. 4, FIG. 6 is a partially cutaway elevational view of the configuration including a large number of dust collector units, and FIG. 7 is an enlarged vertical sectional view of a part of FIG. The right side of FIG. 6 and FIG. 8 are plan views partially shown in cross section as seen from line 8--8 in FIG. 6. 7...Fan, 9...
...Exhaust duct, 10...Housing, 11.
...Entrance, 12...Exit, 14...
- Electrostatic precipitator, 18... Collection structure (cylindrical screen), 20... Disc-shaped end member, 22...
・Ring-shaped end member, 24...Corona electrode, 30
...Condolence, 31...Stop member, 37.
...impermeable sleeve, 40...filter,
45...Screen (cage), 48...
・・Dust collector (unit), 50, 52, 54, 56・・
...Housing wall, 60...Support plate, 67...
... Tightening ring, 80 ... Tension mechanism, 8
2...Bead, 86...Cap, 90...
...Tightening member, 89, 94...Connecting member, 1
08... Vibration means, 120... Damper, 122... Air cylinder, 130, 13
2... Inclined side wall forming a hopper, 134.
...Motor, 140,142...Cover.

Claims (1)

Claims: 1. A housing having an inlet and an outlet for receiving a contaminated gas, and an inlet disposed within the housing and communicating with the contaminated gas inlet, for removing a majority of particulates from the gas flow. an electrostatic precipitating means for separating; a filter means disposed within said housing between said electrostatic precipitating means and an outlet of said housing for separating residual particulates from said gas flow; and an electric field applied to said filter means. and means for directing gas from the contaminated gas inlet through the electrostatic precipitating means and filter means to the outlet of the housing, the electrostatic precipitating means being connected to the contaminated gas inlet of the housing. a cylindrical collection structure having an inlet communicating with the inlet and an outlet axially spaced from the inlet; an elongated corona electrode disposed substantially along the axis of the cylindrical collection structure; , means for applying a potential difference between the cylindrical collection structure and a corona electrode, the cylindrical collection structure having substantially the same axial working length as the corona electrode. a cylindrical screen of conductive material and an impermeable tube adjacent to the cylindrical screen and surrounding most of its axial length so that the gas is the cylindrical collection structure is configured to flow through a major portion of its axial length before exiting the outlet, the filter means coaxially spaced and surrounding the cylindrical collection structure; Consists of a cylindrical filter made of porous dielectric material,
means for applying an electric field to the filter means, a gas-permeable cylindrical body of electrically conductive material disposed between the cylindrical filter and the outlet of the housing, and between the cylindrical body and the electrostatic precipitating means; the gas-permeable cylindrical body is arranged close to the circular body filter, and the interval between the cylindrical collection structure and the cylindrical filter is such that the distance between the filter and the A dust collector characterized in that the interval is larger than the interval between gas-permeable cylindrical bodies. 2. The dust collector according to claim 1, further comprising a vibration means for vibrating the electrostatic precipitation means and the filter means to remove fine particles attached to both means. .