JPH08257331A - Filter element - Google Patents

Abstract

PURPOSE: To provide a filter element used mainly in the mechanical dust collecting method for dust from an incinerator. CONSTITUTION: A filter element 1 is constituted for passing a fluid from outside to inside. Heat-resistant grains 5-7 of given grain size which can be incinerated are set to form a layer of almost given thickness, on the outside of which grains of given grain size smaller than the grains inside are set to form another layer of almost given thickness. Thus a plurality of layers are heated and incinerated to start to form the layers 5-7 constituted of grains larger grain size, and then the layers of grains of smaller grain size are formed successively one by one from the inner side toward the outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a mechanical method for collecting dust from an incinerator.

[0002]

2. Description of the Related Art The conventional mechanical method for collecting dust is mainly a bag filter method. The bag filter is a filter formed by stacking a plurality of layers of synthetic fibers into a tubular shape. The bag filter takes in dust inside the element to perform internal filtration. FIG. 5 shows an example of dust collection in a conventional incinerator. The exhaust gas from the incinerator a enters the cooling device b, and the water supply device c
It is configured to be cooled to the heat resistant temperature of the bag filter d or lower by the spray water from. In the figure, e is a dust collector, f is a chimney, and g is a backwashing pulse air supply device.

Therefore, when backwashing is performed,
It had the drawback that it was difficult to wash it off on average, and it could not withstand a high temperature of 200 ° C or higher due to its material.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a surface filtration structure in which dust (dust) is not trapped inside and is deposited on the outside of the filter and does not enter the inside, and from the inside to the outside. On the other hand, the backwash air jet directed toward the filter surface should go to the filter surface on average, and the filter material should be made of a heat resistant material.

[0005]

In order to solve these problems, the present invention employs the following means.
That is, (1) a layer having a certain particle size is formed in a certain thickness, and a plurality of layers having a larger particle size are arranged in this order from the inside to the outside of the filter element. (2) The granules to be used are heat-resistant ceramic or glass processed into granules, and are heated and pressed to sinter, thereby forming an appropriate gap between the granules. To do.

[0006]

In this way, when filtering from the outside to the inside, the dust is blocked by the surface of the outer granular material layer and does not enter the inside. When the dust has accumulated to some extent on the outer surface of the element, backwash with pulsed air from the inside of the element. The blast air flows through the large gap in the inner large granular body layer and gradually flows to the layer with the narrow gap, and finally reaches the outermost granular body layer, and the dust (dust) clogging the outer surface inside Bounce off and finish backwashing. The granular material layer becomes smaller from the inner side to the outer side, and the gap between them becomes gradually narrower, so that the backwashing air flow does not increase the pressure loss. Moreover, since the average flow rate is sent to the outer layer over the entire surface, backwashing is uniform.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a filter element 1 of the present invention will be described with reference to FIGS. The element 1 is formed into a cylindrical shape from three layers of a collection layer 2, a backwash layer 3, and a strength layer 4 from the outside (in these figures, only one side cross section of the cylindrical body is shown).

Each of the layers 2, 3 and 4 is a sintered body of a granular heat-resistant material (ceramic, glass, etc.), and the granular bodies 5, 6 and 7 having a substantially constant grain size have a constant gap. Can be formed.

Assuming that the granular bodies 5, 6, 7 are spherical bodies having a diameter D, the maximum diameter d of the granular bodies that can pass through this gap is as follows.

[0010]

[Equation 1]

Therefore, the particle size of the granules of the outer layer is 15% of the particle size of the inner granules (ie, the particle size of granules 5 for granules 6 and 6 for granules 7).
It must have the above diameter. Further, the particle size of the granular body 5 of the outermost collection layer 2 needs to be 1 / 0.15 or less of the diameter of the dust to be collected.

The concept of the structure of the filter element 1 is as follows.
When this element 1 is applied to a dust collector of an incinerator, a strength layer is first formed as a layer of a granular body 7 having a large particle size capable of withstanding the pressure of pulsed air from the inside, the pressure of gas from the outside and other forces. 4, and the particle size of the granular body 5 of the collection layer 2 is determined by the particle size of the dust to be collected next.

Therefore, since the particle size of the granular material 5 of the trapping layer 2 and the particle size of the granular material 7 of the strength layer 4 are very different, the backwash air is passed through the gap of the strength layer 4. If it is sent to the trapping layer 2 as it is, a resistance force due to a large pressure loss is exerted, which causes the sintered layer of the trapping layer 2 to be fatigued and damaged. The particle size of the granular material 6 of the intermediate backwash layer 3 is determined so as to prevent this, gradually reduce the backwash air flow, and reduce the pressure loss.

Further, the backwash layer 3 can be made up of a plurality of layers of granular material having a particle size of several stages. With this configuration, the backwashing air flow is evenly distributed to the trapping layer 2, and uneven backwashing can be eliminated.

The filter element 1 of FIGS. 1 and 2
In the situation shown in the figure, there is not much difference in appearance, but in reality, in the case of FIG. 4 are arranged and then heat-sintered to form an integral element. On the other hand, in FIG. 2, the granular bodies 5, 6 and 7 having different grain sizes as described above are individually sintered. Then, the collection layer 2, the backwash layer 3, and the strength layer 4 are formed, and these layers 2, 3 and 4 are laminated to form an element.

Next, the filtration element 1 according to the present invention is
An example applied to the dust collector of the incinerator will be described with reference to FIG. The dust collector 8 includes a main body 9 and a lid 1.
0, the filter element 1, the press fitting 11, and the backwash rod 12 are mainly configured.

A dust outlet 14 is provided in the lower portion of the main body 9 for releasing dust to a dust reservoir 13 which will be described later during backwashing.
However, a gas inlet 15 through which a gas containing dust enters is provided at the upper part. The lid 10 is provided with an inner lid 16.

The screw portion 17 formed at the upper end of the backwash rod 12 penetrating vertically in the filter element 1 is
The pressing fitting 11 is fixed in position by a nut 20 screwed into a boss 18 formed on the lid 10 and screwed into a bolt 19 formed at a lower end.

The backwash rod 12 is constructed as a hollow cylinder having an opening 21 to the outside at the upper end, and an intermediate portion 22 penetrating the inside of the filter element 1.
A plurality of air ejection ports 23 are formed in the. The numeral 24 in the figure denotes a gas outlet opened in the lid 10.

In the dust collector 8 having the above structure, the gas containing dust is introduced into the main body 9 from the gas inlet 15, the dust is filtered by the filter element 1, and the separated dust is The gas is discharged from the dust outlet 14 while the gas is discharged from the gas outlet 24.

In backwashing, the backwashing air press-fitted from the opening 21 is blown from the air jet port 23 of the backwashing rod 12 to the strength layer 4 inside the filter element 1, and then the backwashing layer 3, The dust passing through the trapping layer 2 and clogged is removed.

An outline of the operation will be described with reference to FIG. 4 corresponding to the conventional example shown in FIG. 5. The dust collector 8 takes in the gas discharged from the incinerator 25 and collects the dust as described above. The dust is stored in the dust reservoir 13, and the clean gas is released from the gas outlet 24 to the atmosphere via the chimney 26.

Pulse air is intermittently supplied to the dust collector 8 from the pulse air supply device 27, and the dust adhering to the filter element 1 is brushed off by the above-mentioned backwashing action, and the dust is discharged from the dust outlet 14. Store in the dust storage chamber 13.

In the above embodiments, the dust collector was mainly applied to the application of the filter element of the present invention, but the present invention is also applicable to the filtration of liquid such as the filtration of sludge water and the filtration of a septic tank. It can be used in combination with washing.

[0025]

According to the present invention, particularly in the application to the dust collector, the economical effect is large in that the cooling device which has been conventionally required is unnecessary.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of essential parts of an embodiment of a filter element according to the present invention.

FIG. 2 is a cross-sectional view of essential parts of another embodiment of the filter element according to the present invention.

FIG. 3 is a cross-sectional view showing a state in which the filter element of the present invention is applied to a dust collector.

4 is an explanatory view of a system for collecting dust contained in gas emitted from an incinerator using the dust collector shown in FIG.

5 is an explanatory diagram of a system corresponding to FIG. 4 of the conventional example.

[Explanation of symbols]

 1 Filter element 2 Collection layer 3 Backwash layer 4 Strength layer 5, 6, 7 Granules

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kosuke Hayashi, 3-1, Okawa, Kanazawa-ku, Yokohama-shi, Kanagawa Tokyu Vehicle Manufacturing Co., Ltd., Environmental Project, Development Division (72) Tetsuya Aono, Okawa, Kanazawa-ku, Yokohama-shi, Kanagawa No. 3 Tokyu Vehicle Manufacturing Co., Ltd. Development Division Environmental Project

Claims (2)

[Claims] 1. A filter element configured to allow fluid to pass from the outside to the inside, wherein the particle size of the refractory sinterable granules forms a layer of substantially constant thickness. Smaller particles having a constant particle size are formed on the outside so as to form a layer having a substantially constant thickness. In this way, a layer of particles having a large particle size is successively formed from an inner layer to an outer layer. A filter element arranged in layers and heat-sintered. 2. A filter element configured to allow fluid to pass from the outside to the inside, wherein heat-resistant sinterable granules of different particle sizes and constant sizes are each provided with a substantially constant thickness. A filter element formed by sintering and forming the layers, and stacking these layers in order from the layer of large-granular particles to the layer of small-granular particles from the inside to the outside. .