JPH04104038A - Method and apparatus for detecting broken state of filter cloth in bag-filter type dust collector - Google Patents

Abstract

PURPOSE:To specify the position of broken filter cloth by emitting beam light on an upper casing under the on-line state, and observing the reflected light. CONSTITUTION:A beam light emitter 13 turns an oscillating mechanism 15 and emits beam light into an upper casing 8. Each beam light detector 18 turns an oscillating mechanism 19 and scans gas outlet ports 7 in the upper casing 8. When the detector 18 detects the reflected light in high irregular-reflection density, the detected signal is sent into an operation control device 22. The device 22 judges the position where the reflected light is generated as the position where filter cloth 3 is broken and dust leaks into clean gas based on the detected position signal from an azimuth measuring device 20 and the emitting position signal from an azimuth measuring device 16.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method and apparatus for detecting damage to a filter cloth in a bag filter type dust collector.

<Conventional technology> Conventionally, various dust collectors have been used to remove dust from dust-containing gas and purify the gas, but especially bag filter type dust collectors collect dust-containing gas from the inner or outer surface of a filter cloth. It is widely used because it is suitable for collecting fine dust. In recent years, from the perspective of preventing pollution due to atmospheric tT and dyeing, bag filters with larger capacities are gradually being introduced. It's about time to deal with it.

Here, to explain the external filtration cylindrical bag filter type dust collector, as shown in FIG. They are suspended in multiple rows, and the dust-containing gas sent from the inlet 6 through the duct 5 is filtered out by the outer surface of the filter cloth 3. The filtered clean gas then rises along the inner surface of the filter cloth 3, passes through the gas outlet hole 7 as shown in FIG. 4, is collected in the upper casing 8, and is sent out from the outlet 9. Incidentally, the dust 10 collected by the filter cloth 3 is deposited in the hopper 11 at the lower part.

By the way, if the filter cloth 3 in such a bag filter type dust collector is damaged, some of the dust collected by the filter cloth 3 will leak and contaminate the clean gas, so it is important to detect it early. You need to replace it.

<Problems to be Solved by the Invention> However, in order to detect a damaged filter cloth 3 among a large number of filter cloths 3, it is necessary to stop the dust collector each time and visually inspect the filter cloths 3 one by one off-line. Therefore, it takes a lot of effort and time, and there are problems such as reducing the operating rate of the equipment.

Therefore, as a means of detecting a damaged filter cloth, for example, Japanese Patent Laid-Open No. 52-98273 discloses a method of marking it with a powder of a hue different from the color of the collected dust to make it easier to find it. However, since it is still necessary to stop the dust collector and open all filter cloths one by one off-line for inspection, in the case of large-capacity dust collectors, an increase in the number of inspection man-hours is unavoidable, and the cost becomes enormous. Moreover, it has the disadvantage of causing opportunity loss due to downtime.

Furthermore, Japanese Patent Application Laid-Open No. 1-307424 proposes a method in which sampling devices corresponding to the number of filter cloths are installed to monitor the leakage status of each filter cloth. There is a risk that this will become large and impair economic efficiency.

Because of this current situation, it is recommended that all filter cloths be replaced at the same time if they become damaged, or that a large number of spare filter cloths be kept on hand, as part of planned preventive maintenance. They are forced to take measures such as replacing them with new ones.

Is the present invention as described above? This is a simple and inexpensive collection of bug filter formulas that can be found online to solve problem J! ! An object of the present invention is to provide a method and device for detecting the position of damage to a filter cloth in a machine.

<Means for Solving the Problems> A first aspect of the present invention is to remove a filter that is damaged when filtering dust from a dust-containing gas using a bag filter type dust collector equipped with a plurality of external filtration cylindrical filter cloths. A method for detecting cloth, the method comprising:
A step of sequentially irradiating the gas outlet hole of the filter cloth with a beam of light, a step of detecting the presence or absence of reflected light with a high diffuse reflection density of the irradiated beam light, and a step of detecting the position of the reflected light when the reflected light is detected. A method for detecting damage to a filter cloth in a bag filter type collector is characterized by:

Moreover, the second aspect of the present invention is to install external filtration cylindrical filter cloths in a plurality of rooms. J[A device for detecting a damaged filter cloth in a bag filter type dust collector that is equipped with several rows and filters dust-containing gas sent from a lower duct and discharges clean gas collected in an upper casing to the outside, wherein the upper casing a beam light irradiation device that is attached to the upstream side wall of the filter cloth and sequentially irradiates the gas outlet holes of the filter cloth with beam light; an azimuth angle measuring device that detects the beam light irradiation angle of the beam light irradiation device; A plurality of beam photodetectors are provided on one side wall of the upper casing, which is perpendicular to the optical axis of the beam emitted from the self-beam light irradiation device, and detect reflected light with a high diffuse reflection density while being scanned. , an azimuth measuring device that detects the scanning position of this beam photodetector, a reflected light detection signal detected by the beam photodetector, a scanning position signal at that time, and the beam light irradiation angle signal. Detection of filter cloth damage in a bag filter type dust collector, characterized by comprising: an arithmetic processing unit that determines the position of the filter cloth; and a monitor that displays a position signal of the damaged filter cloth output from the arithmetic processing unit. It is a device.

<Function> As a result of intensive studies to solve the above-mentioned problems, the present inventors found that in the case of a bag filter adult mIR having an external filtration cylindrical filter cloth, all of the clean gas filtered by the filter cloth If we focus on the fact that the light is concentrated in the upper casing and apply the principle that the beam light shining into the darkroom is diffusely reflected by the dust in the air, and the density of the reflected light changes depending on the concentration of the dust, we can prevent damage. The present inventors have discovered that it is possible to identify the filter cloth that has been used, and have completed the present invention.

That is, according to the present invention, by irradiating a beam light onto the gas outlet hole from which clean gas blows out from one side wall of the upper casing and observing the reflected light from the side wall in the right angle direction, it is possible to detect if the filter cloth is damaged. If there is a large amount of dust mixed into the gas blown out from the gas outlet hole, the density of diffused reflection of the beam light will be high, and the position where the highly reflected light occurs can be detected visually or with a beam photodetector such as an ITV camera. However, the damaged filter cloth can be specified based on the azimuth angle of the detected position and the beam light irradiation angle at that time.

<Examples> Examples of the present invention will be described in detail below with reference to the drawings.

As shown in FIG. 1, a plurality of pressure-resistant viewing windows 12 are provided on the side wall 8a of the upper casing 8 opposite to the outlet 9, that is, on the upstream side of the gas flow, and a plurality of light beams are irradiated on the outside of the viewing windows 12. The device 13 is installed so as to irradiate the beam light toward the outlet 9 side, that is, toward the downstream side of the gas flow parallel to the gas flow.

A shutter 14 is interposed between the viewing window 12 and the beam light emitter 13, and the shutter drive device 14a is operated to open the shutter 14 only when the beam light is irradiated. Further, the beam light irradiator 13 is attached with a horizontal swinging mechanism 15 and an azimuth measuring device 16.

Next, on one side wall 8b that is perpendicular to the side wall 8a of the upper casing 8, a plurality of pressure-resistant viewing windows 1 that can be seen through are provided.
7 is provided, and a beam photodetector 18 is attached to each of the viewing windows 17. A horizontal swing mechanism 19 and an azimuth measuring device 20 are attached to these beam photodetectors.

On the other hand, an arithmetic and control unit 22 and a monitor 23 such as a CRT display are installed in the operation room 21.

In this calculation system 4111 device 22, the beam light -
Detection signals from the azimuth angle measuring device 16 of the projector I3, the beam photodetector 18, and the azimuth angle measuring device 20 of the beam photodetector 1 are inputted, and the damaged position of the filter cloth 3 is identified and monitored by the monitor 23. The beam light irradiator 13, the swing mechanism 15 of the beam light irradiator 13, and the gloss drive device 14a
, has a function of outputting an operation command signal to the swinging mechanism 19 of the beam photodetector 18.

The operation of the filter cloth damage detection device of the present invention configured as described above will be described below.

(1) First, the gloss drive device 14a of a certain peephole 12 is operated to open the eyelet 14 in accordance with the U operation command output from the arithmetic and control unit 22.

Note that at this time, the shutters 14 of the other viewing windows 12 remain closed.

(2) Next, the beam light is irradiated into the upper casing 8 while rotating the swinging mechanism 15 of the beam light irradiator 13 at a predetermined angle. The irradiation position at that time is the azimuth angle measuring device 16
, and the irradiation position signal is inputted to the arithmetic and control unit 22 .

■ On the other hand, each beam photodetector 18 is operated by an operation command from the arithmetic and control unit 22, and the mechanism swings in unison! 9 at a predetermined angle, open the gas outlet hole 7 in the upper casing 8.
scan. The scanning position at that time is detected moment by moment by the azimuth measuring device 20 and inputted to the arithmetic and control device 22 .

■ Therefore, if any of the beam photodetectors 18 detects reflected light with a high density of diffused reflection, the arithmetic and control unit 2
At this time, the arithmetic and control unit 22 simultaneously reads the detected position signal of the azimuth angle measuring device 20 and the irradiation position signal of the azimuth angle measuring device 16. As a result, the arithmetic and control unit 22 determines that the position where the reflected light is generated is where the filter cloth 3 has been damaged and dust has leaked into the clean gas.

In addition, at the moment when the filter cloth 3 is damaged and dust leaks, according to the investigation of the present inventor, the concentration range varies from a normal concentration range (for example, 10 mg#+') to a high concentration (for example, 40 mz/s").
(above)), and then as it flows downstream, it diffuses and the concentration decreases, so the diffuse reflection density is the second
It has been found that the change trend shown in the figure is shown.

Furthermore, since a similar phenomenon occurs even when leaks occur at multiple locations, it goes without saying that they can be detected separately.

(2) As a result, the arithmetic and control unit 22 can calculate the detected position signal of the azimuth angle measuring device 20 and the irradiation position signal of the azimuth angle measuring device 16, which are read simultaneously at the time of inputting the reflected light detection signal from the beam photodetector 18. The position of the gas outlet hole 7 is calculated and output to the monitor 23 to notify the operator.

This allows the operator to decide whether to arrange to replace the damaged filter cloth immediately or at a later date.

■Next, if it is found that reflected light with a high diffuse reflection density cannot be detected by any of the beam photodetectors 18, the arithmetic and control unit 22 operates the tire drive device 14a of the peephole 12 to shut down the shutter 7. 14 is closed, a beam light irradiation command is issued to the other beam light irradiator 13, and the gas outlet hole 7 in the upper casing 8 is scanned by the beam light detector 1 in the same procedure as above to detect diffused reflection. Detects the presence or absence of high-density reflected light.

(2) After completing the beam light irradiation using the number of installed beam light irradiators 13, the beam light irradiators 13 are restarted in order starting from the first beam light irradiator 13.

In the above embodiment, it has been explained that a plurality of beam light irradiators 13 are installed and the beam light is irradiated while switching, but the present invention is not limited to this. The light may be irradiated from each viewing window 12 while moving on the rail.

Further, although the description has been made assuming that the beam photodetector 18 is used to detect the reflected light, the present invention can also be used in combination with visual detection and a protractor with a magnifying trowel such as a Leher measuring device. The position of the leaking filter cloth 3 can be specified with an accuracy of .

The filter cloth damage detection device of the present invention has a filter cloth number of 2496 and a filtration area of 6200@2. Processing air volume; 7870m
When applied to an external filtration long pulse type bag filter type dust collector with a large filtration area of ff/min, damage to the filter cloth can be detected reliably without requiring manpower, and its function works effectively. It was confirmed.

<Effects of the Invention> As explained above, according to the present invention, the position of a damaged filter cloth can be identified by irradiating a beam light onto the upper casing in an online state and observing the reflected light. Therefore, damaged filter cloths can be replaced in a short time with minimal workload.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing an embodiment of a filter cloth damage detection device according to the present invention, Fig. 2 is a characteristic diagram showing changes in diffuse reflection density, and Fig. 3 shows a part of a conventional bag filter type dust collector. A side view shown in cross section, FIG. 4 is a view taken along the line A--A in FIG. 3. 2... Chamber, 3... Filter cloth, 6... Inlet, 7... Gas outlet hole, 8... Upper casing, 9... Outlet, 12... Peephole, 13...・Beam light irradiator, 14...Shutter, 1
5... Swing mechanism 16... Azimuth angle measuring device, 17...
- Peephole, 18... Beam photodetector, 19
... Swing mechanism, 20... Azimuth angle measuring device, 22...
- Arithmetic control unit, 23...monitor.

Claims (1)

[Scope of Claims] 1. A method for detecting a damaged filter cloth when filtering dust from dust-containing gas using a bag filter type dust collector equipped with a plurality of external filtration cylindrical filter cloths, comprising: A process of sequentially irradiating the gas outlet hole of the filter cloth with a beam of light, a process of detecting the presence or absence of reflected light with a high density of diffused reflection of the irradiated beam, and a process of determining the position of the reflected light when detected. A method for detecting damage to a filter cloth in a bag filter type dust collector, comprising the steps of: 2. Equipped with multiple rows of external filtration cylindrical filter cloth in multiple rooms,
A device for detecting a damaged filter cloth in a bag filter type dust collector that filters dust-containing gas sent from a lower duct and discharges clean gas collected in an upper casing to the outside, the device comprising: a side wall on the upstream side of the upper casing; a beam light irradiation device that is attached to the filter cloth and sequentially irradiates the gas outlet holes of the filter cloth with beam light; an azimuth measuring device that detects the beam light irradiation angle of the beam light irradiation device; a plurality of beam photodetectors provided on one side wall of the upper casing that is perpendicular to the optical axis of the beam light to be scanned and detecting reflected light with a high density of diffused reflection; an azimuth measuring device that detects the scanning position of the filter; and determining the position of the damaged filter cloth from the reflected light detection signal detected by the beam photodetector, the scanning position signal at that time, and the beam light irradiation angle signal. A filter cloth damage status detection device in a bag filter type dust collector, comprising: an arithmetic processing unit; and a monitor that displays a position signal of the damaged filter cloth output from the arithmetic processing unit.