JPS6018204B2 - Filter media, dust collection method and equipment that involve transportation and separation of dust - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a dust collection method and a dust collection apparatus using a granular filter material such as sand, gravel, ceramics, and refractories.
This relates to filter media, dust collection methods and equipment that involve transportation and separation of dust, and is particularly suitable for removing reducing gases such as converter waste gas with a high carbon monoxide content and explosive gases. .

In order to remove dust from exhaust gas, especially high-temperature exhaust gas, this is a filtration type dust collector in which heat-resistant filtration material in the form of granules such as sand, gravel, or ceramics is movably installed in the dust collector body in the form of panels or layers. The present inventors have already developed this, but in these devices, the filter media with dust attached is extracted continuously or intermittently from the dust collector body, so the filter media with dust attached is removed. There has been a demand for efficient separation of filter material and dust by processing the filter material, and for effectively recycling and reusing the filter material after separation, thereby reducing the operating cost of the entire device.

In particular, when removing reducing gas or explosive gas such as converter waste gas with a high carbon monoxide content, there is a risk that the leaking gas (hereinafter referred to as "leak gas") may oxidize and explode. For example, when the processing gas temperature is 800 to 10
In the case of 00oo, the temperature of the filter medium with dust adhering to it discharged from the dust collector body is around 600 to 800 qo, which poses a problem in that it is difficult to handle and highly dangerous. The present invention was made to solve the above-mentioned problems, and after extracting the filter medium with dust attached continuously or intermittently from the main body of the dust collector, the mixture of the filter medium and dust is used as a seal gas. Nitrogen gas is blown in as a transfer gas or simply as a sealing gas and transferred to a high place while cooling to separate the filter material from the dust, and the nitrogen gas containing dust is removed, cooled, or dust removed (hereinafter simply referred to as By recycling and reusing the treated gas after removing dust and cooling, it is possible to prevent oxidation and explosion of the treated gas.
The object of the present invention is to provide a filter material that can be easily handled by cooling to 400 qo or less, a dust collection method that involves transportation and separation of dust, and an apparatus therefor.

The dust collection method of the present invention involves transporting and separating dust and dust by passing reducing gas and explosive gas containing dust through a dust collection layer made of a granular filter material to separate and separate dust in the gas. After removal, the agglomerated filter media with dust attached is extracted, and then nitrogen gas is blown into the mixture of the three agglomerated filter media and the dust, and the mixture is cooled and transported to a high place to separate the agglomerated filter media and the dust. This system has three features: the granular filter material can be recycled and reused, and the nitrogen gas containing dust can be removed and cooled before being recycled.

Hereinafter, a dust collection device for carrying out the dust collection method of the present invention will be explained based on the drawings.

FIG. 1 shows one embodiment of the dust collection device of the present invention, and is a system-related explanatory diagram in the case where a transfer pipe is used as the granular filter material/dust transfer means and a cyclone is used as the dust collector. 1 is a dust collector body having a dust-containing gas inlet 2 at one end and a clean gas outlet 3 at the other end, and a metal louver, wire mesh, metal Supports 4, such as perforated plates, are provided at regular intervals at right angles or nearly right angles to the flow of the dust-containing gas, and between the supports 4, a granular filter material 5 such as sand, gravel, ceramics, refractory material, etc. is placed in the form of a panel or A dust collection layer 6 is provided which is movably filled and retained in a layered manner, and a granular filter material supply hopper 7 is connected to the upper part of this dust collection layer 6, and the particles with dust attached are connected to the lower part of the dust collection layer 6. A dust collector 10 is formed by connecting a discharger 8 for extracting the bulk filter material.

Further, a discharge pipe 12 of a nitrogen gas circulation blower 11 is connected to the lower part of the discharger 8, and a granular filter material/dust transfer means consisting of a transfer pipe 13 is connected to the discharge pipe 12 and the lower part of the discharger 8. A granular filtration material/dust separator consisting of a cyclone 14 provided above the granular filtration material supply hopper 7 is connected to this transfer pipe 13 to transport the filtration material and dust to a high place and to separate the filtration material from the filtration material. A transportation/separation device 15 is formed to separate the filter material from dust and reuse the filter material by circulation. Further, the nitrogen gas outlet 1 of the cyclone 14
6 is connected to the suction side of the nitrogen gas circulation blower 11 via a dust collector consisting of a cyclone 17 and a nitrogen gas cooler 18 so that cooled nitrogen gas can be freely circulated. 2
0 is a nitrogen gas supply pipe for replenishing only the amount consumed due to leakage, and 21 is a dust extraction pipe.

In the dust collector configured as described above, the dust-containing high-temperature reducing gas and explosive gas introduced from the dust-containing gas inlet 2 are removed by the dust collection layer 6 and converted into clean gas. The clean gas is discharged from the outlet 3.
That is, the dust in the gas adheres to the surface of the granular filter material, and is retained in the spaces between the filter materials, resulting in high-performance dust collection. On the other hand, the granular filter material with dust attached is removed by the discharger 8.
The nitrogen gas is continuously or intermittently extracted from the dust collector main body 1 and introduced into the transfer pipe 13 by pressurized cooled nitrogen gas sent from the nitrogen gas circulation blower 11. While being transported to a high place into the first cyclone 14, the nitrogen gas containing dust and the granular filter material are separated. In this case, the diameter of the granular filter media is several ribs ~
The diameter of the dust is from several to several tens of diameters, and since the particle sizes of the two are significantly different, the two can be easily separated using a separator with a simple structure such as a cyclone.
The separated granular filter material is circulated to the supply hopper 7 for reuse, and the nitrogen gas containing dust is introduced to the second cyclone 17, where the dust and nitrogen gas are separated, and the dust is extracted. After being extracted from the pipe 21 and cooled by the nitrogen gas cooler 18, the nitrogen gas is circulated and reused by the circulation blower 11. If the main body of the dust collector is a boiler type, the hot water from the nitrogen gas cooler can be used to supply water to the boiler, allowing heat recovery.
Another advantage is that the dust can be collected at only one location, from the dust collector. FIG. 2 shows another embodiment of the dust collecting device of the present invention, and is a system diagram for explaining the case where a bag filter is used as the dust collector.

That is, a nitrogen gas cooler 18 is directly connected to the nitrogen gas outlet 16 of the cyclone 14, and a bag filter 22 is connected to this cooler 18 as a dust collector to cool the nitrogen gas containing dust and then remove the dust. It is configured as follows. Since the dust-containing nitrogen gas cooled in this way is removed, it has the advantage that a bag filter suitable for removing fine dust can be used, although it can only be used at low temperatures in terms of heat resistance. 23 is a dust extraction pipe.

Other configurations and operations are similar to those of the dust collector shown in FIG. Next, still another embodiment of the dust collecting device of the present invention will be described based on FIG. 3.

In FIG. 3, a transport/separation device 26 is formed using a bucket elevator 24 as a particulate filter material/dust transfer means and a vibration node 25 as a particulate filter material/dust separator. The dust-adhered granular filter material to be extracted is transported to a high place by the bucket elevator 24 to a vibrating bar 25 provided at the top of the supply hopper 7 while being sealed with nitrogen gas, and the granular filter material and the dust are removed. On the other hand, the transport/separation device 26, specifically, the dust-containing nitrogen gas discharged from the nitrogen gas outlet 27 of the bucket elevator 24 is removed, cooled, and recycled for reuse. In this case, as shown in FIG. 2, the dust-containing nitrogen gas may be first cooled and then removed by a bag filter. 28 is a vibration motor, and 30 is a dust extraction pipe.

The other configurations and operations are similar to those of the dust collector shown in FIGS. m and 2. As explained above, in the present invention, the filter media, the dust transport/separation system, and the nitrogen gas circulation system are sealed with nitrogen gas in a closed loop system, making it possible to prevent leak gas oxidation, explosion, etc. Since the gas is circulated through the cooler, the filter medium and dust are cooled when the filter medium with hot dust attached is transferred to a high place, making it easy to separate the filter medium and dust by appropriate hand IJ. It can be carried out at low temperatures, and since the nitrogen gas is recycled, it is extremely economical as it is only necessary to replenish the amount consumed due to leakage.

[Brief explanation of drawings]

Fig. 1 shows one embodiment of the dust collector of the present invention, and is a systematic explanatory diagram when a cyclone is used as a dust collector, and Fig. 2 shows another embodiment of the dust collector of the present invention. 3 is a systematic explanatory diagram when a bag filter is used as a dust collector. FIG. FIG. 2 is a systematic explanatory diagram when using a bucket elevator. 1... Dust collector body, 2... Dust-containing gas inlet, 3... Clean gas outlet, 4...
Support, 5... Granular filter medium, 6...
Dust collection layer, 7... Granular filter material supply hopper, 8
... Discharge machine, 10 ... Dust collector, 11 ... Nitrogen gas circulation blower, 12 ... Discharge pipe, 13 ... Transfer pipe, 14 ... Cyclone, 15. ·…·transportation·
Separation device, 16... Nitrogen gas outlet, 17...
...Cyclone, 18...Nitrogen gas cooler,
20... Nitrogen gas supply pipe, 22... Bag filter, 24... Bucket elevator, 2
5... Vibration node, 26... Transportation/separation device,
27...Nitrogen gas outlet. *Figure Z

Claims (1)

[Scope of Claims] 1. After passing a reducing gas or an explosive gas containing dust through a dust collection layer made of a granular filter material to separate and remove dust from the gas, granular filtration with attached dust is performed. The material is extracted, and then nitrogen gas is blown into the mixture of the agglomerated filter media and dust, and the mixture is cooled and transported to a high place to separate the agglomerated filter media and dust so that the agglomerated filter media can be recycled and reused. A dust collection method that involves transporting and separating dust, a filter material that is characterized by the fact that the nitrogen gas containing dust is removed and cooled, and then recycled and reused. 2. A dust collection layer is provided in the dust collector body in which granular filter media is movably filled and held between supports in the form of panels or layers, and a granular filter material supply hopper is installed above this dust collection layer. At the same time, a discharger is connected to the bottom of the dust collection layer to form a dust collector, and a discharge pipe of a blower for nitrogen gas circulation is connected to the bottom of this discharger, and a granular filter is connected to the bottom of the discharger. A particle/dust transfer means is connected, and a particle/dust separator provided at the top of the agglomerate filter medium supply hopper is connected to this transfer means to transport the filter medium and dust to a high place and separate them. to form a transportation/separation device for circulating and reusing the filter media, and furthermore, the nitrogen gas outlet of this transportation/separation device is connected to the suction of the nitrogen gas circulation blower via a dust collector and a nitrogen gas cooler. A dust collection device that transports and separates dust and a filter material that connects cooled nitrogen gas to the side so that it can be freely circulated.