JPH0734847B2 - Dust collector for grain co-drying facility - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet dust collector for treating dust contained in exhaust gas generated from various devices installed in a grain co-drying facility.

[0002]

2. Description of the Related Art Conventionally, a spray type wet dust collector shown in FIG. 8 or a spray type wet dust collector with a primary settling chamber shown in FIG. 9 is used in a co-drying facility for grains. This type of dust collector has a mist chamber 2 in which a spray nozzle 1 is arranged at the top.
The dust in the air guided from the dust head 3 to the mist chamber 2 is captured and collected by water droplets (mist) sprayed from the spray nozzle 1.

The conventional apparatus shown in FIGS. 8 and 9 will be further described. A mist separator 4 is arranged above the spray nozzle 1, and a regulator 5 made of a mesh plate is arranged below the mist separator 4. A filter 1 is provided on the bottom plate 6 of the mist chamber 2.
1 is provided with a wash water drop port 12,
There is provided a liter conveyor 13 equipped with a scraper for scraping out the dust trapped in 1. A water tank 14 is provided further below the liter conveyor 13, and a sludge conveyor 15 having a scraper for scraping dust accumulated at the bottom of the water tank is provided. The cleaning water in the water tank 14 is pumped up by the pump 16 and sprayed from the spray nozzle 1. The exhaust duct 7 such as a dryer and a storage bottle in the co-drying facility and the exhaust duct 8 such as a mechanical dust collector are shown in FIG.
In the device shown in FIG. 9, the dust head 3 is opened, and in the device shown in FIG. 9, the dust head 3 is communicated with the dust head 3 via the primary settling chamber 17.

The water sprayed from the spray nozzle 1 captures dust floating in the air in the mist chamber 2 while falling in the mist chamber 2 in the form of mist, and falls on the bottom plate 6.
A water film is formed on the regulator 5 by the water sprayed from the spray nozzle 1, and the air in the mist chamber 2 flows through this water film, so that the dust in the air can be removed more reliably. ing. The cleaned air is
After water droplets are removed by the mist separator 4, the water droplets are discharged into the atmosphere.

The water that has captured the dust and dropped on the bottom plate 6 of the mist chamber 2 is guided to the wash water drop port 12 by the gutter 9 formed on the bottom plate 6, passes through the filter 11 and flows down to the water tank 14. The coarse dust in the cleaning water captured by the filter 11 is scraped out by the liter conveyor 13, and together with the dust scraped by the sludge conveyor 15, the dust container 1
8 is discharged. The fine dust that has passed through the filter 11 settles in the water tank 14 and accumulates on the bottom, which is scraped out by the sludge conveyor 15 and discharged into the dust container 18.

In the apparatus of FIG. 9 provided with the primary settling chamber,
Dust with a large specific gravity in the air falls to the bottom of the primary settling chamber and is separated.

[0007]

The spray type dust collecting apparatus as shown in FIGS. 8 and 9 has a small pressure loss (10
Since it has a water column of up to 25 mm), it has the advantage of requiring less electricity from the blower, but has the problem of low dust removal efficiency. Therefore, it is suitable as a dust collector for single exhaust treatment of large air flow and low dust concentration air, such as exhaust from a dryer or storage bin, but it is difficult to sufficiently remove high dust concentration air. .

[0008] In the conventional grain co-drying facility, as shown in FIG.
It is equipped with a dust collector as shown in Fig. 2, and this dust collector is equipped with a duct 7 for exhaust air with a large air volume and a low dust concentration discharged from a drier or a storage bin and a small air volume with a high dust concentration exhausted from a mechanical dust collector or the like. In many cases, the structure is such that all the ducts 8 are connected and processed. In such a case, when exhaust gas with a small air volume and a high dust concentration is processed, fine dust with a low partial dust removal efficiency (dust with a particle size of about 20 micrometers or less) is emitted to the atmosphere as white smoke, which causes a problem. There was a chance

In order to solve the above problems, the present invention increases the running cost of a blower or installs a device in a spray type wet dust collector suitable for removing exhaust gas with a large air volume and low dust concentration. An object of the present invention is to obtain a dust collector that can reliably remove dust with a small air volume and high dust concentration without significantly increasing the area and installation cost.

[0010]

According to the present invention, high dust removal efficiency dust collectors are arranged in parallel adjacent to the mist chamber 2 of a spray type wet dust collector generally used. The Venturi Scrubber 2 is a highly efficient dust collector.
1, a jet scrubber, a hydro filter (packed bed scrubber) 31, a bag filter 41, etc. can be used. Among the dust collection ducts installed in each facility of the co-drying facility, the duct 7 for large air volume and low dust air communicates with the mist chamber 2 of the spray dust collector, and the duct 8 for small air volume and high dust air has high dust removal. It communicates with the efficient dust collectors 21, 31, 41.

The bottom plate 6 of the mist chamber 2 is extended below the high dust removal efficiency dust collectors 21, 31, 41 for adsorbing the dust captured by the high dust removal efficiency dust collectors 21, 31, 41. The washing water supply devices 26 and 43 are provided. Cleaning water for mist chamber 2 and high dust removal efficiency dust collector 2
The cleaning waters 1, 31, 41 are guided to the common dust discharging devices 13, 15 provided therebelow.

Between the mist chamber 2 of the spray type dust collector and the installation area of the high dust removal efficiency dust collectors 31, 31, 41,
By providing partition walls 22 and 23, and providing a trap 27 at the bottom of the partition walls 22 and 23 that is blocked by the cleaning water flowing along the bottom plate 6, the mist chamber 2 of the spray type wet dust collector and high dust removal efficiency dust collection are provided. It is also possible to compartmentalize the devices 21, 31, 41.

[0013]

In the above apparatus, the exhaust air having a large air volume and a low dust concentration is directly introduced into the mist chamber of the spray type wet dust collecting apparatus, and the dust is removed by the same processing as the conventional apparatus shown in FIG. On the other hand, exhaust air with a small air volume and high dust concentration is installed at a high dust removal efficiency dust collector 21, 3 adjacent to the spray type wet dust collector.
Dust is removed at 1, 41. Then, the dust captured by the two dust collectors having different dust removal efficiencies is common to the dust discharge device 1
It is discharged at 3, 15. High dust removal efficiency dust collector 21, 3
The cleaning water supplied from the water supply devices 26 and 43 provided in the first and the first 41, respectively, causes the captured dust to flow down along the bottom plate 6 to be guided to the common dust discharge devices 13 and 15, and also to collect the dust on the bottom plate 6. Prevents accumulation.

[0014]

1 to 3 show a first embodiment of the present invention in which a Venturi scrubber is used as the high dust removal efficiency dust collecting devices 21, 31, 41. Since the structure and operation of the spray type wet dust collecting apparatus in the following apparatus are similar to those of the conventional apparatus shown in FIG.

The venturi scrubber 21 is open to an exhaust cylinder 24 formed by partitioning the part of the dust head 3 adjacent to the mist chamber 2 with partition walls 22 and 23, and the exhaust duct 8 from the mechanical dust collector is a venturi. It is connected to the scrubber 21. On the other hand, the exhaust duct 8 such as a dryer or a storage bottle is provided from the dust head 3 to the mist chamber 2
Is directly led to. The bottom plate 6 of the mist chamber 2 is extended to the lower side of the exhaust cylinder 24 with an inclination necessary for allowing water to flow down, and a gutter 9 is provided along this extension direction. A branch pipe 26 is provided in the discharge pipe 25 of the pump 16 that feeds the water in the water tank 14 to the spray nozzle 1, and the branch pipe opens to the throat portion of the venturi scrubber 21.

The lower end of the partition wall 22 that divides the exhaust cylinder 24 and the mist chamber 2 is provided so that no gap is formed between the partition wall 22 and the bottom plate 6, and a trap 27 is formed in the gutter 9 portion. That is, as shown in FIG. 3, a recess 28 is formed in the lower part of the partition 22 of the gutter 9, and the partition 22 projects into the gutter 9 with a gap provided between the bottom of the recess 28. ing. When the dust collector is in operation, the cleaning water from the Venturi scrubber 21 side once collects in this recess 28, and then flows out into the gutter on the mist chamber 2 side, and the protruding end of the partition wall 22 has this recess. It is immersed in the washing water collected in the place 28, and the airtight state between the mist chamber 2 and the exhaust cylinder 24 is maintained.

When the exhaust air having a small air volume and a high dust concentration flows from the mechanical dust collector into the dust collector, the dust in the exhaust gas is supplied by the venturi scrubber 21 from the branch pipe 26 that opens to the throat portion. It is captured by the wash water and falls under the exhaust cylinder 24, and flows down through the gutter 9 to the wash water drop port 12. The filter 11 of the wash water drop port 12
Dust that is formed of a plate having small holes such as punching metal and that is captured by the wash water in the venturi scrubber 21 and the mist chamber 2 is filtered out by the filter 11 and the coarse dust is scraped out by the liter conveyor 13. Be done. The fine dust that has passed through the filter 11 is stored in the water tank 1.
It settles at 4, and is discharged at the sludge conveyor 15.

FIG. 4 and FIG. 5 show an embodiment of an apparatus using a hydrofilter as a high dust collecting efficiency dust collecting apparatus. In this embodiment, three hydrofilters 31 are provided on the side surface of the mist chamber 2 of the spray type wet dust collector by partition walls 22 and 23, and the cleaning water supplied to the hydrofilter 31 is The mist chamber 2 is guided to the wash water drop port 12 and the water tank 14 through a bottom plate common to the bottom plate 6. The side wall of the hydro filter 31 has a small air flow and a high dust concentration exhaust duct 7
Is opened, and the air of high dust concentration is discharged to the atmosphere through the packed bed 32 and the eliminator 33.

The exhaust duct 7 having a large air volume and a low dust concentration is directly connected to the mist chamber 2 from the dust head 3. The dust-containing air having a small air volume and a high dust concentration guided from the exhaust duct 8 to the hydrofilter 31 has a large amount of coarse dust mainly captured in the partitioned shower chambers 34, and the space between the packed layers 32 spread over the upper portion thereof. After passing through, the fine dust is captured, and is emitted into the atmosphere through the eliminator 33. The treatment of the wash water that has dropped to the bottom of the hydrofilter 31 is the same as that of the first embodiment.

FIGS. 6 and 7 show an embodiment in which a bag filter is provided as a high dust removal efficiency dust collector. On the side surface of the mist chamber 2 of the spray type wet dust collector, a high dust concentration air treatment chamber provided with a large number of bag filters 41 is provided by being partitioned by a partition wall 23, and is connected to a mechanical dust collector or the like to provide a small air flow and high dust concentration. The exhaust duct 8 is connected to the side surface. A backwash nozzle 42 is arranged above the bag filter 41, and a sprinkling pipe 43 is arranged at a high position of the bottom plate 6.

The dust of the exhaust of the high dust concentration air that has flowed in from the exhaust duct 8 is captured by the filter cloth of the bag filter 41. Air is intermittently jetted from the backwash nozzle 42 to sequentially wash the bag filter 41, and the dust washed away from the bag filter drops onto the bottom plate 6 by the backwash air and is supplied from the water spray pipe 43. It is washed away by the wash water that flows through the wash water drop port 12 and flows down to the water tank 14. The captured coarse dust is discharged by the liter conveyor 13 and the fine dust is discharged by the sludge conveyor 15, as in the case of the above-described first and second embodiments.

[0022]

According to the structure of the present invention, the exhaust having a large air flow and low dust concentration and the exhaust having a small air flow and high dust concentration can be removed by a common dust collector, and the air having a high dust concentration can be removed. It is possible to prevent dust from being emitted as white smoke without being collected during processing.

In the grain co-drying facility, the exhaust air with a high dust concentration is about 10 to 30% of the total treated air volume, and therefore only the high-efficiency dust collector is required to process it. The running cost can be significantly reduced as compared with the case where all the exhaust air is treated with a high dust removal efficiency dust collector in order to keep the value below the target value. Further, since the common discharge device collects and discharges the coarse dust and the fine dust captured by the wash water, the device can be made inexpensive and the installation area of the device can be reduced.

Further, in the conventional apparatus, dust deposits and accumulations due to mist entrainment were found inside the duct header, and removal work was required after operation, but a high dust removal efficiency dust collector was provided in the duct header section. If this is done, the cleaning water constantly rinses the lower part of the duct header, so that dust does not accumulate on this part, and therefore its removal work is unnecessary.

Further, in the apparatus of the present invention, even when the bag filter is used, the dust is adsorbed with water and washed away, so that the secondary scattering of the captured dust can be prevented.

[Brief description of drawings]

FIG. 1 is a sectional front view schematically showing the internal structure of the first embodiment.

FIG. 2 is a sectional side view schematically showing the internal structure of the first embodiment.

FIG. 3 is an enlarged view showing a trap section.

FIG. 4 is a view similar to FIG. 1 of the second embodiment.

FIG. 5 is a view similar to FIG. 2 of the second embodiment.

FIG. 6 is a view similar to FIG. 1 of the third embodiment.

FIG. 7 is a view similar to FIG. 2 of the third embodiment.

FIG. 8 is a sectional front view schematically showing the internal structure of a conventional device.

FIG. 9 is a sectional front view schematically showing the internal structure of another conventional device.

[Explanation of symbols]

 2 Mist chamber 6 Bottom plate 7 Exhaust duct 8 Exhaust duct 13 Litter conveyor 15 Sludge conveyor 21 Venturi scrubber 22 Bulkhead 23 Bulkhead 24 Exhaust trunk 26 Branch pipe 27 Trap 31 Hydro filter 34 Shower chamber 41 Bag filter 43 Sprinkling pipe

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B01D 47/06 Z 47/10 Z

Claims (2)

[Claims] 1. A mist chamber (2) of a spray type wet dust collector.
The high dust removal efficiency dust collectors (21), (31), (41) are located adjacent to, and the bottom plate (6) of the mist chamber (2) is the high dust removal efficiency dust collector (21), (41). 31), (41) is extended to below,
The high dust removal efficiency dust collectors (21), (31), (41) are equipped with wash water supply devices (26), (43) for adsorbing the dust trapped, and the mist chamber (2) Cleaning water and high dust removal efficiency dust collector
The washing water of (21), (31), and (41) are both guided to the common dust discharge device (13) and (15) provided below it, and the duct (7) for large air volume and low dust air is Mist chamber of spray type dust collector (2)
And a duct (8) of small air volume and high dust air is connected to a high dust removal efficiency dust collector (21), (31), (41). apparatus. 2. The mist chamber (2) of the spray type dust collector and the installation areas (24), (34) of the high dust removal efficiency dust collectors (21), (31), (41).
And are partitioned by bulkheads (22), (23).
A trap (27) is provided at the bottom of the (23), the trap (27) being blocked by washing water flowing along the bottom plate (6).
Dust collector for the grain co-drying facility described.