JPH08155335A - Electrostatic precipitator - Google Patents

Abstract

PURPOSE: To remove a part of dust in dust-contg. gas before dust collection in an electrostatic precipitating part and also to sufficiently straighten the dust-contg. gas to lead it to the electrostatic precipitating part. CONSTITUTION: Louvers 18 having inverted L-shaped sections each consisting of an impact plate almost at a right angle to the flow of dust-contg. gas 9 from a gas inlet 6 and a straightening plate extending almost horizontally toward the downstream side (right-handed) of the impact plates from the upper ends thereof are arranged in a multistage manner on the upstream side (left- handed) of an electrostatic precipitating part of a casing 2 at such proper intervals that the lower stage louvers 18 retreat toward the downstream side of the upper stage louvers 18 in order and the impact plates of the upper stage louvers 18 overlap the impact plates of the lower stage louvers 18 on the upstream side thereof. A part of dust 9a in the dust-contg. gas 9 introduced form the gas inlet 6 is made to come into collide with the impact plates of the louvers 18 to blow it off, and immediately after that, the dust-contg. gas 9 is passed through between the straightening plates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic precipitator which is particularly effective for collecting dust-containing gas having a high concentration.

[0002]

2. Description of the Related Art Conventionally, by charging a high voltage between an alternating discharge electrode and a dust collecting electrode, a charge band is formed between both electrodes, and a dust-containing gas is passed through this charge band. Therefore, an electrostatic precipitator is known in which dust in the dust-containing gas is charged, and the charged dust is adsorbed and collected by a dust collecting electrode having an opposite potential.

In such an electrostatic precipitator, when handling a high-concentration dust-containing gas having an inlet dust content exceeding several hundred g / Nm ³ , the introduction duct for guiding the dust-containing gas from the dust generation source is installed in the electrostatic precipitator. Of the casing is connected to the gas inlet of the casing by directing downward from above, and the flow of the dust-containing gas introduced downward from the gas inlet is converted from downward to upward by a large number of louvers to temporarily remove dust. The main part was to collect dust mainly by guiding it to the electrostatic precipitator after gravity separating it with inertial force.

FIG. 4 shows an example of the above electrostatic precipitator. In the figure, 1 is an electrostatic precipitator, 2 is a casing of the electrostatic precipitator 1, and inside the casing 2, a discharge electrode 3 and a dust collecting electrode 4 are provided.
An electrostatic precipitator 5 is held by alternately arranging and in the width direction (direction perpendicular to the drawing).

A gas inlet 6 is provided on one side of the casing 2.
However, gas outlets 7 are provided on the other side, and the gas inlet 6 contains dust-containing gas 9 from a dust generation source 8 (a vertical mill in the illustrated example) such as a crusher or a preheater for cement equipment. Is connected downward from above the casing 2, and the gas outlet 7 is connected to an exhaust duct 11 for exhausting the treated gas 9 ′ collected.

Further, on the upstream side of the electrostatic precipitator 5 in the casing 2, louvers 12 inclined so as to have an upward slope toward the electrostatic precipitator 5 are arranged in multiple stages. The lower position on the upstream side of the louver 12 and the electric dust collector 5
Hoppers 13 and 14 are respectively formed at the lower positions of the.

Thus, the dust-containing gas 9 from the dust generation source 8
Is introduced downward from the gas inlet 6 of the electrostatic precipitator 1 via the introduction duct 10 and is once diverted upward when passing between the louvers 12, so that the dust in the dust-containing gas 9 at this time. Part of 9a is gravitationally separated by inertial force and collected in the hopper 13 below.

Further, the dust-containing gas 9 that has passed through the louver 12 becomes a horizontal flow toward the gas outlet 7 and passes through the electric dust collector 5, where the dust-containing gas 9 contained in the gas 9 is discharged. The dust 9a is charged and adsorbed by the dust collecting electrode 4 to be collected. The dust 9a is occasionally blown off from the dust collecting electrode 4 by a hammering device (not shown) and collected in the lower hopper 14, while dust is collected. The treated gas 9'is discharged from the gas outlet 7 through the exhaust duct 1
It is discharged to 1.

[0009]

However, in the electrostatic precipitator 1 having the conventional structure as described above, the dust-containing gas 9
Since the dust-containing gas 9 must be introduced as a downward flow to the gas inlet 6 in order to gravity-separate a part of the dust 9a therein, for example, the dust generation source 8 is at a position equal to or lower than the electrostatic precipitator 1. In such a case, it is necessary to adopt a structure in which the introducing duct 10 is purposefully extended to a position above the electrostatic precipitator 1 and then inverted downward as shown in the figure. There is a problem that the installation space of the introduction duct 10 is unnecessarily increased and the electrostatic precipitator 1 itself is also subject to restrictions on the arrangement.

Further, in this type of electrostatic precipitator 1,
It is important in terms of efficiency to guide the dust-containing gas 9 to the electrostatic precipitator 5 in a uniform flow and perform dust collection in a state where the dust 9a is well dispersed.
Since the flow of the dust-containing gas 9 introduced downward from the gas inlet 6 immediately before the electrostatic precipitator 5 in the inside is suddenly changed upward by the louver 12, it is uniform with respect to the electrostatic precipitator 5. There is a problem that it is difficult to guide the dust-containing gas 9 by the flow, and the dust 9a in the dust-containing gas 9 is biased to a strong flow portion due to gravity settling or the like to lower the dust collection efficiency. In order to achieve this, it is conceivable to increase the distance L between the arrangement position of the louver 12 and the electrostatic precipitator 5 to rectify the dust-containing gas 9 that has passed through the louver 12, but in such a case This causes a problem that the electrostatic precipitator 1 becomes large.

The present invention has been made in view of the above circumstances, and reduces the space for disposing the introduction duct, eliminates restrictions on the disposition of the electrostatic precipitator, and further improves the dust-containing gas guided to the electrostatic precipitator. The purpose is to improve the dust collection efficiency by rectifying.

[0012]

According to the present invention, a dust-containing gas is introduced from a gas inlet provided on one side of a casing holding an electrostatic precipitator, and the dust-containing gas is introduced to the other side of the casing. In an electrostatic precipitator configured to pass through the electrostatic precipitator and collect dust while flowing horizontally toward a provided gas outlet, an electrostatic precipitator in the casing is configured to include a gas from the gas inlet on an upstream side of the electrostatic precipitator. A louver having an inverted L-shaped cross section, which includes a collision plate that is substantially perpendicular to the flow of dust gas and a straightening plate that extends substantially horizontally from the upper end of the collision plate toward the downstream side, and the lower louver is sequentially downstream of the upper louver. The pre-duster is arranged in multiple stages with appropriate mutual intervals so that the collision plates of the upper louvers overlap with each other on the upstream side of the collision plates of the lower louvers.

The introduction duct for guiding the dust-containing gas from the dust generating source can be guided from the lower side of the casing upward to be connected to the gas inlet, or can be laterally guided from the side of the casing to be connected to the gas inlet. is there.

[0014]

Therefore, in the present invention, the dust-containing gas introduced from the gas inlet and reaching the pre-duster reaches the collision plates of the louvers of each stage and is converted into a flow rising between the collision plates, and then, The flow reaches the straightening vanes of the louvers of each stage, is converted into a flow that flows substantially horizontally between the straightening vanes, and is guided to the electrostatic precipitator.

Here, when the dust-containing gas reaches the collision plates of the louvers of each stage and is converted into a flow rising between the collision plates, a part of the dust in the dust-containing gas is generated. Due to the inertial force, it collides with the collision plate and is blown off, so that the dust-containing gas having a low concentration is guided to the electrostatic precipitator on the downstream side of the preduster.

Further, since the dust-containing gas from which a part of the dust has been blown off as described above is rectified when passing between the respective rectifying plates, it is guided to the electrostatic precipitator in a uniform flow. In addition, most of the dust collides with the collision plate and is dispersed even if the dust is not removed by the collision with the collision plate. When rectified by doing so, the dust in the dust-containing gas is guided to the electrostatic precipitator in a state of being well dispersed.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the present invention, in which parts designated by the same reference numerals as those in FIG. 4 represent the same parts.

Similar to the electrostatic precipitator 1 of FIG. 4 described above, the dust-containing gas 9 is introduced through the gas inlet 6 provided on one side of the casing 2 holding the electric dust-collecting section 5, and the dust-containing gas 9 is introduced. In the electrostatic precipitator 15 configured to pass through the electrostatic precipitator 5 to collect dust while horizontally flowing toward the gas outlet 7 provided on the other side of the casing 2, the dust-containing gas from the dust source 8 An introducing duct 10 for guiding the gas 9 is guided upward from below the casing 2 and connected to the gas inlet 6, and a flow of the dust-containing gas 9 from the gas inlet 6 is provided on the upstream side of the electrostatic precipitator 5 in the casing 2. A louver 18 having an inverted L-shaped cross section, which includes a collision plate 16 that is substantially orthogonal to the collision plate 16 and a straightening plate 17 that extends substantially horizontally from the upper end of the collision plate 16 toward the downstream side.
(Refer to FIG. 2) for the upper louver 18 and the lower louver 18
Colliding with the collision plate 16 of the upper louver 18
Are arranged in multiple stages at appropriate intervals so that they overlap on the upstream side of the collision plate 16 of the lower louver 18.
To provide.

Further, hoppers 13 and 14 are formed below the preduster 19 and below the electric dust collector 5, respectively.

Thus, the dust-containing gas 9 from the dust generation source 8
Is introduced upward from the gas inlet 6 of the electrostatic precipitator 1 through the introduction duct 10, and after the introduction, goes to the downstream side and reaches the preduster 19 while gradually approaching a horizontal flow.

Dust-containing gas 9 reaching the preduster 19
Is converted into a flow that hits the collision plates 16 of the louvers 18 of each stage and rises between the collision plates 16, and then reaches the straightening plates 17 of the louvers 18 of each stage and reaches each straightening plate 17 of each.
It is converted into a flow that flows toward the downstream side substantially horizontally between the two and is guided to the electrostatic precipitator 5.

Here, the dust-containing gas 9 is used as the louver 1 at each stage.
When the collision plates 16 of No. 8 hit and collide with each other, the dust 9a in the dust-containing gas 9 collides with the collision plates 16 due to inertial force. As a result, the dust-containing gas 9 having a low concentration is introduced to the electrostatic precipitator 5 on the downstream side of the preduster 19.

Further, since the dust-containing gas 9 from which a part of the dust 9a has been blown off as described above is rectified when passing between the respective rectifying plates 17, the dust-collecting gas 9 is made uniform with respect to the electrostatic precipitator 5. It will be guided by the flow.

In addition, most of the dust 9a is not removed by the collision with the collision plate 16, but most of the dust 9a is generated.
Since the dust 9a in the dust-containing gas 9 is satisfactorily dispersed, if it is rectified by passing it between the rectifying plates 17 immediately after being dispersed in this way, the dust 9a in the dust-containing gas 9 remains well dispersed. You will be guided to Part 5.

Further, the dust-containing gas 9 introduced to the electrostatic precipitator 5
Is subjected to a dust collecting process by being charged with the dust dispersed in the dust-containing gas 9 and adsorbed to the dust collecting electrode 4, and becomes a treated gas 9 ′, which is discharged from the gas outlet 7 to the discharge duct 11. .

The dust 9a removed by the preduster 19 is collected by the lower hopper 13, and the dust 9a collected by the electric dust collector 5 is removed from the dust collecting electrode 4 at any time by a hammering device (not shown). Lowered hopper 1
Recovered in 4.

Therefore, according to the above embodiment, the casing 2
Introducing duct 10 that is directed upward from below the gas inlet 6
Even if it is directly connected to the collision plate 1 of each louver 18, a part of the dust 9a in the dust-containing gas 9 introduced from the gas inlet 6 is connected.
By colliding with 6 and brushing it off, the electrostatic precipitator 5
Since it is possible to reduce the dust concentration of the dust-containing gas 9 introduced to the intake duct 10, the introduction duct 10 is connected to the electrostatic precipitator 15 as in the conventional case.
There is no need to adopt a structure in which the duct is extended downward and then inverted downward.
The arrangement space occupied by the electrostatic precipitator 15 can be greatly reduced as compared with the conventional one, and the restriction on the arrangement of the electrostatic precipitator 15 can be eliminated.

Immediately after most of the dust 9a in the dust-containing gas 9 is dispersed by the collision of the louvers 18 with the collision plate 16, the dust-containing gas 9 is rectified by passing between the respective rectifying plates 17. Since it is possible to convert the dust-containing gas 9 into the dust 9
Since a can be guided to the electrostatic precipitator 5 in a state where it is well dispersed, the dust collection efficiency can be remarkably improved as compared with the conventional case.

FIG. 3 shows another embodiment of the present invention.
This is an example in which the introduction duct 10 for guiding the dust-containing gas 9 from the dust generation source 8 is laterally guided from the side of the casing 2 and connected to the gas inlet 6, and in this case also, the same effect as that of the above-described embodiment is exhibited. obtain.

The electrostatic precipitator of the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0032]

According to the electric dust collector of the present invention described above,
Various excellent effects as described below can be obtained.

(I) A part of the dust in the dust-containing gas introduced from the gas inlet is collided with the collision plate of each louver to be blown off, whereby the dust concentration of the dust-containing gas introduced to the electrostatic precipitator is adjusted. Since it can be reduced, it is no longer necessary to adopt a structure in which the introduction duct is extended to a position above the electrostatic precipitator and then inverted downward as in the conventional case.
Alternatively, since it is possible to connect the introduction duct that is laterally guided from the side of the casing to the gas outlet as it is,
The installation space occupied by the introduction duct can be significantly reduced compared to the conventional one, and the restriction on the arrangement of the electrostatic precipitator can be eliminated.

(II) Immediately after most of the dust in the dust-containing gas is dispersed by the collision of each louver with the collision plate, the dust-containing gas can be rectified by passing the dust-containing gas between the respective rectifying plates. Therefore, the dust-containing gas can be guided to the electric dust collector while dust is being dispersed well, and the dust collection efficiency can be remarkably improved as compared with the conventional case.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention.

FIG. 2 is an enlarged view of the louver of FIG.

FIG. 3 is a schematic view showing another embodiment of the present invention.

FIG. 4 is a schematic view showing a conventional example.

[Explanation of symbols]

 2 casing 5 electric dust collector 6 gas inlet 7 gas outlet 8 dust source 9 dust-containing gas 9a dust 10 introduction duct 15 electric dust collector 16 collision plate 17 straightening plate 18 louver 19 preduster

Claims (3)

[Claims] 1. A dust-containing gas is introduced from a gas inlet provided on one side of a casing holding an electrostatic precipitator, and the dust-containing gas is directed toward a gas outlet provided on the other side of the casing. In an electrostatic precipitator configured to pass through the electrostatic precipitator while flowing horizontally to collect the dust, an upstream side of the electrostatic precipitator in the casing is substantially perpendicular to a flow of dust-containing gas from the gas inlet. A louver having an inverted L-shaped cross section composed of a large collision plate and a straightening plate extending substantially horizontally from the upper end of the collision plate toward the downstream side, the lower louver sequentially retracts to the upper louver toward the downstream side, and the upper louver collides. An electrostatic precipitator characterized in that a pre-duster is provided by arranging a plurality of plates at appropriate intervals so that the plates overlap each other on the upstream side of the collision plate of the lower louver. 2. The electrostatic precipitator according to claim 1, wherein an introduction duct for guiding the dust-containing gas from the dust generation source is guided upward from below the casing and connected to the gas inlet. 3. The electrostatic precipitator according to claim 1, wherein an introduction duct for guiding the dust-containing gas from the dust source is guided laterally from the side of the casing and connected to the gas inlet.