JPH07733A - Dust collector and backwash method for filter part thereof - Google Patents

Abstract

PURPOSE:To obtain a dust collector having high backwash effect with a small quantity of high pressure air by constituting one or more of filter parts of honeycomb type filter elements and providing a backwash nozzle for each element. CONSTITUTION:A backwash device for a dust collector is provided with honeycomb packs 11 constituted of honeycomb type filter elements, backwash air pipes 23 for sending backwash air to the packs, and backwash nozzles for jetting backwash air to the elements. since the backwash nozzle is provided for each element, pulse waves of high pressure air are jetted so that one nozzle may cover one element on backwashing, and the range of simultaneous backwashing is limited to all of the filter packs in the same stage. Therefore, it will be sufficient that the pressure difference between backwash air and a clean air part is small and that backwash time is little and the quantity of backwash air is small. Since backwash is performed from honeycomb packs of the upper stage arranged in the upper part to those of the lower stage in order, the removed dust is guided downward in good order.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust remover for high-temperature dust-containing gas, and more particularly to a dust remover having a backwash mechanism and a method for backwashing a filter portion in the dust remover.

[0002]

2. Description of the Related Art In a dust remover for high temperature dust-containing gas,
As shown in FIG. 8, a filter element 01 using a cylindrical porous ceramics body is used, and dust is removed by filtering the dust-containing gas with the filter element 01. Originally, the dust that was not filtered and remained on the dust-containing gas side should be successively separated and dropped to the hopper 05 side by its own weight, but this is not always the case. In order to deal with this, backwashing from the clean gas outlet pipe 04 side with high pressure air is performed. However, in an initial stage dust remover consisting of a single filter section, backwashing is performed simultaneously over the entire range, and disturbances such as pressure fluctuations and temperature fluctuations are given to the downstream equipment, Even on the dust-containing gas side, peeling dust was trapped and re-adsorbed on the filter in the next filtration step.

Also, in a dust remover using a honeycomb type porous ceramics body, as in the dust remover having a cylindrical filter portion, backwash air is injected from the clean gas outlet pipe side, so Backwashing will be performed simultaneously for the range. Although the above-mentioned drawbacks are ameliorated when one filter part is integrally backwashed for each filter part, there is a considerable space and distance between the backwash nozzle and the filter element, so that one backwash is performed. In order to effectively remove dust by backwashing at each end element within the range, use high-pressure air with a large differential pressure from the clean gas pressure, increase the air flow rate, and lengthen the backwash time. In particular, since the thickness of the filter wall of the honeycomb type filter element is relatively thin, it is necessary to backwash frequently.

[0004]

The present invention has been made in order to solve the problems of the prior art as described above, and it is possible to improve the backwashing effect and reduce the usage amount and usage rate of high pressure air. It is an object to provide a high performance dust remover. Further, the present invention is effective in backwashing the filter part in this dust removing device in a short time, without dividing the clean gas chamber side, and imparting pressure fluctuation and temperature fluctuation to the equipment on the downstream side. It is an object to provide a backwashing method that can be performed without the need.

[0005]

DISCLOSURE OF THE INVENTION The present invention is directed to a can body which is arranged almost vertically and is provided with a dust-containing gas inlet at the upper part thereof and a dust hopper is connected to the lower part thereof, and a dust-containing gas flow direction inside the can body. And a filter portion composed of a porous ceramics filter element having a dust removal function, which is disposed along the line, and is configured to take out clean gas after dust removal from a clean gas outlet provided in the can body. In order to solve the above-mentioned problem in one, at least one of the filter parts is composed of a plurality of honeycomb packs composed of honeycomb type filter elements, and the backwashing for each honeycomb pack is arranged in the clean gas chamber of the filter part. A structure having a backwashing device including a working air pipe and a backwashing nozzle provided for each filter element from the air pipe is adopted.

In the present invention, the backwash nozzle may be provided with a slit-shaped opening. Further, in order to solve the above problems in the method of backwashing the filter part of the dust remover of the present invention, in the dust remover, the backwash device is used for at least a part of the plurality of honeycomb packs arranged in the same stage. Use the method of backwashing. The cleaning in this case can be performed for each honeycomb pack facing each other in the same stage, or for all the honeycomb packs facing each other arranged in the same stage at the same time.

In order to solve the above-mentioned problems in the method of backwashing the filter part of the dust removing device, the present invention sequentially reverses the upper-stage honeycomb pack of the filter part arranged above to the lower-stage honeycomb pack. The method of backwashing with a washing device is adopted. As described above, in the method of backwashing the filter portion according to the present invention, the backwashing is performed with the backwashing air from the backwash nozzle for each filter element using the filter pack as a basic unit.

[0008]

The backwashing device of the dust removing apparatus according to the present invention comprises a backwashing air pipe for each honeycomb pack composed of honeycomb type filter elements and a backwashing nozzle provided for each filter element from the backwashing air pipe. It is equipped with Here, specifically showing a configuration example of the honeycomb pack, FIG. 4 is an example of a cross section of the honeycomb pack 11 configured by the honeycomb type filter element 12. Honeycomb pack 1
An example of the honeycomb-type filter element 12 constituting No. 1 is shown in FIG. FIG. 7 is a diagram for explaining the function of this filter element 12, in which (B) is in the process of dust removal, (C)
Shows the flow during backwashing.

As described above, since the backwashing nozzle is provided for each filter element as a feature of the dust removing apparatus according to the present invention, during backwashing, one nozzle covers one element with high pressure air. A pulse wave is ejected, and the range of simultaneous backwashing is stopped up to all filter packs of the same stage.

Therefore, unlike the conventional case of backwashing with one filter unit and backwashing from the nozzle provided in the clean gas pipe outside the can body, the pressure difference between the backwashing air and the clean gas unit is also large. It does not need to be taken, the time required for backwashing and the amount of air for backwashing are small, and the effect of backwashing is large. And, this effect has the merit that the clean gas chambers are not divided and the clean gas chambers for the entire plurality of honeycomb filter parts are combined into one and are not changed.

Further, according to the present invention, when the method of backwashing the honeycomb packs in the upper stage of the filter portion arranged in the upper part in order to the honeycomb packs in the lower stage is adopted, the filter elements are peeled by the backwashing. It is possible to sequentially guide the dust that has been generated downwards.

If a backwash nozzle having a slit-like shape according to the present invention is used instead of the normal nozzle shape, the honeycomb-type element end portion has a quadrangular shape, so that the backwash nozzle does not overlap with other elements. The target filter element can be backwashed efficiently.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a dust remover and a backwashing method therefor according to an embodiment of the present invention will be specifically described below with reference to FIGS. In FIG. 1, reference numeral 1 designates a can body, the inside of which is lined with a refractory brick 16 in its entirety. A dust-containing gas inlet 2 is attached to the upper part of the can body 1 which stands vertically. The inside of the can body 1 is divided by the partition wall duct 13 so that the outside is the clean gas passage 5 side,
The inside is partitioned into the dust-containing gas passage 3 side, and this dust-containing gas passage 3 communicates from the inlet 2 to the dust hopper 4 at the bottom of the can body.
On the other hand, the clean gas passage 5 goes down between the refractory brick 16 and the dust-containing gas passage 3 and is connected to the clean gas outlet 6 which is an outlet to the outside at the level of the dust hopper 4.

In the present embodiment, each honeycomb filter portion as a main part of the dust removing device has a plurality of stages n, and each filter portion is composed of 12 honeycomb packs 11. That is, two rows of honeycomb packs 11 on one side face each other across the dust-containing gas passage 3, and three layers of these honeycomb packs 11 overlap each other to form one filter portion, but a different number may be used. . 2 and 3 are partial cross-sectional views of the first embodiment of FIG. 1 and show the arrangement of the honeycomb packs 11. To explain the backwash system in the apparatus shown in FIG. 1, a backwash air mother pipe 21 is output from the high-pressure air source 20, and three branch pipes are branched from this mother pipe 21 to each filter section. And a backwash control valve is provided for each one.

When referring to the first filter section 7, there are three control valves, namely, first filter section backwash control valves 22-1, 22-2 and 22-3, each of which is located in each stage of the first filter section 7. It is in charge of four honeycomb packs 11 and is branched into four backwashing air pipes 23 to each honeycomb pack 11 after the control valves 22-1, 22-2 and 22-3. Each of the air pipes 23 enters the inside of the can body 1 through the backwash pipe seat 24, and finally a collecting pipe, that is, one to four horizontal pipes in the vertical direction is taken out, and there are five slit-type pipes in each pipe. A backwash nozzle 31 is provided.

The second and nth filter sections 8 have the same structure. Further, in this first embodiment, two packs of the minimum flow rate ensuring honeycomb packs 17 are installed on the upper part of the dust hopper 4 and are small with 5 filter elements per pack, but a minimum flow rate is secured with a total of 10 filter elements, This 2-pack backwash line is also provided.

In the dust removing device having the above-mentioned structure,
The dust-containing gas introduced into the can body 1 from the dust-containing gas inlet 2 first flows into the first filter portion 7 through the partition duct 13.
While passing through the dust-containing gas passage 3 in the center, the dust is filtered by the filter component ratio and moved to the clean gas passage 5 side. The remaining dust-containing gas moves through the duct to the second filter portion arranged on the lower side, is filtered in the same manner, and finally is the minimum gas amount securing pack provided in the upper part of the dust hopper by the nth filter portion 8. All is filtered leaving 17 minutes.

Most of the dust separated in each part of these filters falls to the dust hopper 4 due to their own weight and downward gas flow, but a part of the dust adheres and accumulates on the wall surface of the filter element 12 of each part. . Therefore, backwashing is performed to eliminate this and maintain dust removal efficiency.
The order, operating time, interval, etc. are set in advance,
It is carried out accordingly.

In the first embodiment, the order is to start from the four opposing filter packs at the uppermost stage of the first filter section, and then the middle and lower sections of the same section, and further to the uppermost stage of the second filter section, in order of the filter section immediately below. Finally, one cycle is completed with the minimum flow rate ensuring honeycomb pack 17 provided in the dust hopper 4 section.

This backwash will be described in detail with respect to the first filter section. First, when the backwash control valve 22-1 of the uppermost 4-pack is opened by the timer, the backwash air mother connected to the high-pressure air source 20. High pressure air from the pipe 21 is controlled by the control valve 22-1.
Through the four pipes 23 on the downstream side to reach the collecting pipe installed on the clean gas side of each honeycomb pack, and the pulsed impact pressure wave is filtered from the slit type nozzle 31 immediately after each filter element 12. The ceramic having a thickness of about 1 m / m is reversely transmitted from the clean gas side of the element 12 to the dust-containing gas side, and at the same time, the dust deposited and deposited on the dust-containing gas side is separated. The opening time of the backwash control valve is very short, about 1 second.

The separated dust rides in the dust-containing duct by its own weight and the downward gas flow, and falls downward. After an appropriate time, the backwashing control valve 22-2 of the middle four packs of the first filter unit 7 is opened, and the backwashing of each middle pack is performed as in the uppermost stage. Similarly, the separated dust falls below the middle stage. After that, backwashing is sequentially performed according to the setting of the timer, such as the lower part, the upper part of the second filter part, the middle part, and the lower part. This order is the same even when the nth filter unit 8 of the final filter unit is reached.

In the case of the first embodiment, since the minimum flow rate ensuring honeycomb packs 17 (10 elements) are installed downward on the dust hopper, it is guaranteed that the peeled dust of the nth filter portion 8 will fall. In addition, since the backwash of the pack 17 itself is attached downward, there is no problem. In this embodiment, in order to reduce the amount of high-pressure air for backwashing and to enhance the backwashing effect of the honeycomb element, FIG.
The slit type backwash nozzle 31 for exclusive use of the honeycomb type filter element as shown in FIG.

The present invention has been specifically described above based on the illustrated embodiments, but the present invention is not limited to these embodiments, and the shape and structure thereof are within the scope of the present invention shown in the claims. It goes without saying that various changes may be added to the. For example, in the above embodiment, four honeycomb packs in the same stage are configured to be backwashed at the same time, but in some cases, two honeycomb packs arranged to face each other may be backwashed simultaneously.

[0024]

As described in detail above, according to the dust removing apparatus of the present invention, at least one or more filter parts each composed of a plurality of honeycomb packs constituted by honeycomb type filter elements are provided. Backwashing of the unit can be carried out in a honeycomb pack unit, and with a backwash nozzle for each filter element, and there is no need to separate the clean gas chamber side as in the conventional case, pressure to the equipment on the downstream side, Effective backwashing with fine texture can be performed without changing the temperature. Further, according to the present invention, the backwashing is conducted from the upper stage to the lower stage in order to guide the separated dust to the lower dust hopper in an orderly manner, thus improving the efficiency of the dust removing device,
It can greatly contribute to the improvement of reliability.

[Brief description of drawings]

FIG. 1 is an overall cross-sectional view of a dust remover according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a part of the dust removing device shown in FIG.

FIG. 3 is a plan sectional view of the device shown in FIG.

FIG. 4 is a side sectional view showing an example of a honeycomb pack used in the dust remover according to the present invention.

Fig. 5 is an external perspective view showing an example of a honeycomb type filter element used in the dust remover according to the present invention.

6 is a partially enlarged perspective view of a portion A in FIG.

[Fig. 7] Fig. 7 is a diagram for explaining the dust removal and backwash conditions in the honeycomb filter element used in the dust removal device of the present invention.
Is a cross-sectional view showing the configuration, (B) is a dust removal state, and (C) is a cross-sectional view showing a backwash state.

FIG. 8 is a sectional view showing a conventional dust remover using a cylindrical filter element.

[Explanation of symbols]

 1 can body 2 dust-containing gas inlet 3 dust-containing gas passage 4 dust hopper 5 clean gas passage 6 clean gas outlet 7 first filter portion 8 nth filter portion 9 first filter portion supporting device 10 nth filter portion supporting device 11 honeycomb Pack 12 Honeycomb type filter element 13 Partition wall duct 14 Pack support frame 15 Pack seal part 16 Refractory brick 17 Honeycomb pack for ensuring a minimum flow rate 20 High pressure air source 21 Backwash air mother pipe 22 First filter part backwash control valve 23 Reverse Washing air pipe 24 Backwashing pipe seat 25 Pack backwashing air pipe 26 Second filter part backwashing control valve 27 First backwashing device 28 Second backwashing device 29 First filter part backwashing nozzle 30 Second filter Part backwash nozzle 31 Backwash nozzle 32 Ensure minimum flow rate Pack backwash control valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hisataka Urakata 1-1 1-1 Atsunoura-machi, Nagasaki-shi Nagasaki Shipyard Ltd. (72) Inventor Tetsuya Fujino 1-1 1-1 Atsunoura-machi, Nagasaki Mitsubishi Heavy Industries Ltd Inside the shipyard (72) Yuichiro Kitagawa 1-1 1-1 Atsunoura-machi, Nagasaki City Mitsubishi Heavy Industries Ltd. Nagasaki Shipyard

Claims (4)

[Claims] 1. A can body which is arranged vertically and has a dust-containing gas inlet at the upper part and a dust hopper connected to the lower part, and a dust removing function which is arranged along the flow direction of the dust-containing gas inside the can body. In a dust removing device having a filter portion composed of a porous ceramics filter element having the above, and one or more of the filter portions are honeycomb filters in a dust removing device for taking out clean gas after dust removal from a clean gas outlet provided in the can body. It is composed of a plurality of honeycomb packs composed of elements, and is arranged in the clean gas chamber of the filter part, and is provided for each filter element from the backwashing air pipe and the air pipe for each honeycomb pack. A dust remover comprising a backwash device having a backwash nozzle. 2. The dust remover according to claim 1, wherein the backwash nozzle has an opening formed in a slit shape. 3. The filter according to claim 1, wherein at least a part of the plurality of honeycomb packs arranged in the same stage is backwashed by the backwashing device. Part backwash method. 4. The dust remover according to claim 1 or 2, wherein backwashing is performed by the backwashing device sequentially from a honeycomb pack in an upper stage of a filter section arranged in an upper portion to a honeycomb pack in a lower stage. The method of backwashing the filter part.