JPS6221568B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas treatment device equipped with a catalyst tank that performs deodorization, denitrification, etc. as well as dust removal. This relates to a device that does not cause clogging.

A small test method is used to reduce or oxidize harmful substances such as nitrogen oxides, carbon monoxide, and malodors contained in exhaust gas emitted from boilers, incinerators, drying rooms, etc., into harmless substances using catalysts. Although it is effective in plants, in medium-sized or larger equipment, problems occur frequently as the catalyst tank becomes clogged and the catalyst deteriorates rapidly due to the influence of dust, by-products, etc., and even though it is still a success, There is no such situation.

In order to make it easier for dust to pass through and prevent clogging, it has been proposed to use honeycomb or pipe type catalysts, but these are more expensive than granular catalysts and also cause pollution problems as dust gets mixed into the exhaust gas. or,
Because the thickness of the catalyst through which exhaust gas passes is quite thick,
The problem is that the resistance is large and the energy required for drafting is also quite large.

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus that is equipped with a clogging prevention device, has a thin layer catalyst tank with low passage resistance, and is capable of processing dirty gas including smoke and the like.

In order to achieve the above object, the gist of the apparatus of the present invention is to provide a dust exhaust chamber, a vortex chamber, a primary dust collection chamber, a catalyst chamber, a secondary dust collection chamber, and an exhaust chamber in order from the bottom inside the vertical hollow column. A vortex blade is provided at the top of the vortex chamber, a processing gas inlet is opened in the tangential direction at the bottom of the vortex blade, and a dust fall tube is attached to the center to form a conical annular dust collection section in the primary dust collection chamber. , the dust collection part is connected to the dust falling tube of the vortex chamber, a catalyst tank containing a spherical catalyst is installed inside the inverted conical double wire mesh in the catalyst chamber, and a catalyst tank containing a spherical catalyst is installed inside the catalyst tank along the conical generatrix of the catalyst tank. A pipe is installed, a motor is attached to rotate the pipe, and air, steam, etc. are injected through a small hole in the pipe to backwash dust adhering to the catalyst tank and pre-treat or regenerate the catalyst. It's because I did it.

The configuration of the apparatus of the present invention will be explained based on an embodiment shown in the drawings. As shown in Fig. 1, inside the vertical processing column 1, from the bottom, a dust removal chamber 2, a swirl chamber 3, an annular groove-shaped primary dust collection chamber 4, a catalyst chamber 5, an annular groove-shaped secondary A dust collection chamber 6 is provided, and a suction port of a suction pipe 7 is opened in the tangential direction at the bottom of the swirl chamber 3. A dust fall tube 13 is placed in the center of the swirl blade 8 at the top of the swirl chamber 3.
Install. A conical guide 9 is placed below the primary dust collection chamber 4.
A primary dust collection chamber 10 is formed between the outer periphery of the mounting guide 9 and the inner periphery of the primary dust collection chamber 4. A primary dust collection chamber 4 and a catalyst chamber 5 are separated by a chevron-shaped cross-section guide 11. The secondary dust collection chamber 6 is located on the upper outer periphery of the catalyst chamber 5, and the secondary dust collection chamber 12 is formed between the inner periphery thereof and the outer periphery of the catalyst chamber 5. An exhaust chamber 14 is provided coaxially above the catalyst chamber 5, and an exhaust duct 15 opens into the exhaust chamber, and the exhaust duct 15 opens to the outside air directly or through an exhaust fan 16. The primary and secondary dust collecting sections 10 and 12 pass through a drop tube 13 in the swirl chamber 3 via a return pipe 17. The return pipe 17 is the drop tube 13
The drop tube 1 opens in the tangential or chordal direction.
A ventilation pipe 18 leading to the primary dust collection chamber 4 is provided in the center of the dust collection chamber 3.

An inverted conical catalyst tank 20 is disposed in the catalyst chamber 5 at its axis. The catalyst tank 20 has a double inner and outer wire mesh 21,
22 and the granular catalyst (alumina,
(platinum, palladium, activated carbon, etc.)23. A backwashing device 24 equipped with an ejection pipe 30 along the generatrix of the inner conical wire mesh 21 is suspended from a rotary joint 25 attached to the axis of the ceiling of the exhaust chamber 14. The backwashing device 24 is rotated about its axis by being rotationally driven by a deceleration motor 26 provided above the exhaust chamber 14 via a rotary joint 25.

As shown in FIG. 2, the inner and outer wire mesh 2 of the catalyst tank 20
The layer thickness between 1 and 22 is 20 to 100 mm,
The upper part of the wire meshes 21 and 22 is a double cone plate 27
The lower part is connected to the cone cap 28. Since there is a relatively large annular space between the inner and outer cones of the double cone plate 27, if the granular catalyst 23 is filled up to that extent at the beginning, even if the space between the catalysts gets clogged and the volume is reduced during use, The upper surface of the catalyst is never lower than the upper edges of the wire meshes 21, 22. The backwash pipe 24 has an axial core pipe 29 that passes through the backwash pipe 24.
A large number of pores 31 are provided in the ejection pipe 30 at a pitch of about 5 mm, and a partition plate 32 is provided along the back side of the ejection pipe 30.
Install. The axial tube 29 is connected to a rotary joint 25 that is connected to a gas source (not shown) such as compressed air or steam, and while the ejection tube 30 is rotated, gas is injected through the pores 31 into the catalyst in the wire meshes 21 and 22. 23 to backwash the catalyst.

Next, the operation of the apparatus of the present invention will be explained based on the same embodiment. Start the exhaust fan 16 or
When a natural draft is applied to the exhaust duct 15, the dirty gas to be treated is transferred from the suction pipe 7 to the swirl chamber 3.
The dust is attracted in the tangential direction and rises while swirling inside, passes through the swirl vanes 8, becomes a whirlpool, and enters the primary dust collection chamber 4. In the primary dust collection chamber 4, dust of 20 microns or more, such as soot and smoke, is guided to the 1 by the centrifugal force caused by the vortex.
It collides with the peripheral wall of 1, stalls, falls into the primary dust collecting section 10, and further enters the falling tube 17 via the return pipe.
Fine dust and gas enter the catalyst chamber 5 through the center of the guide 11 and reach the catalyst tank 20 while swirling. As the gas passes through the granular catalyst 23, it is treated, rendered harmless, and discharged from the exhaust chamber 14 via the exhaust duct 15. On the other hand, if the dust remains on the surface of the catalyst 23, it will clog the catalyst, but since the backwash pipe 24 rotates and injects compressed air etc. from inside the catalyst tank 20, the dust remains on the surface of the catalyst 23.
Dust adhering to the surface is blown away and no clogging occurs. The blown dust rides on the vortex and rises, enters the upper secondary dust collection chamber 6, accumulates in the secondary dust collection section, and further passes through the return pipe 17 and reaches the drop tube 13. The dust and gas entering the falling tube 13 from the primary and secondary dust collecting sections 10 and 12 swirl, and the gas passes through the central ventilation pipe 18 and rises, but the dust falls into the dust exhaust chamber 2 below. The dust in the dust exhaust chamber 2 is discharged at an appropriate time.

Although the layer thickness of the catalyst tank 20 depends on the amount of gas to be treated,
It is thin at 20 to 100 mm and has low ventilation resistance. In addition, since the gas swirling over the entire surface of the wide conical surface is vented to the catalyst 23, the gas passes through uniformly without being unevenly distributed. Since a special carrier is not required simply by filling the spherical catalyst 23 between the double wire meshes 21 and 22, the cost of the catalyst becomes very low. A partition plate 32 is attached to the back side of the gas ejection hole 31 to cut off the flow of processing gas in that area and also prevent the ejected airflow from spreading, so the backwashing effect of the ejected gas is extremely strong. .

When steam is used as the gas ejected from the pores 31 of the backwashing device 24, carbon, tar, etc. adhering to the catalyst 23 can be easily removed from the catalyst surface because a water gas reaction occurs. Furthermore, since gas that oxidizes or reduces the catalyst can be ejected from the pores 31, the backwashing device 24 not only prevents clogging of the catalyst, but also can be used for pretreatment and regeneration of the catalyst. can.

In the device of the present invention, most of the dust in the gas is centrifuged using a vortex flow, and then first collected near the top of the inverted conical wire net catalyst layer using a chevron-shaped guide, and then the dust in the gas is rotated around the outside of the tank. This system allows the tank to pass almost evenly over the entire surface, making it possible to reduce the layer thickness of the tank, allowing the packed catalyst to work effectively in all areas and with low ventilation resistance. Partition plates are installed on the left and right sides of the machine to block the flow of processing gas in those areas during backwashing, and at the same time direct the ejected airflow strongly to the wire mesh surface to prevent dust clogging as much as possible. Due to the cooperation of the above-mentioned functions, it is possible to process a large amount of dirty gas considering the size of the device.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an apparatus according to an embodiment of the present invention;
FIG. 2 is a perspective view of the main part of FIG. 1. 1... Processing round column, 2... Dust exhaust chamber, 3... Vortex chamber, 4... Primary dust collection chamber, 5... Catalyst chamber, 6... Secondary dust collection chamber, 7... Suction pipe, 8 ...vortex blade,
9...Conical guide, 11...Chevron-shaped guide, 13...
...Drop tube, 14...Exhaust chamber, 15...Exhaust duct, 17...Return pipe, 18...Inner pipe, 20...Catalyst tank, 21, 22...Internal and external metal steel,
23...Catalyst, 24...Backwash device, jet pipe, 3
0,32...Partition plate.

Claims (1)

[Claims] 1. A vortex blade, a conical guide with an annular groove-shaped primary dust collection chamber on the outside, and a catalyst chamber are installed in order from the bottom in an upright processing column with suction pipes and exhaust ducts attached tangentially to the lower and upper ends, respectively. , a double wire mesh inverted conical catalyst layer is installed in the catalyst chamber, a mountain-shaped guide is provided below the tank to collect the gas flow to the center in the circular tower, and an annular groove-shaped guide is installed inside the circular tower above the tank. A gas processing device equipped with a catalyst tank, which is provided with a secondary dust collection chamber, and in which a pressurized gas jet pipe with left and right partition plates that rotates along the back surface of the tank is arranged inside the tank.