JPH01184052A - Mechanical dust collector - Google Patents

Abstract

PURPOSE:To reduce attachment of ash to the inner surface of a dust discharge pipe, by providing a cylinder having a thin wall thickness within the dust discharge pipe, without changing the construction of a conventional cyclone cell and dust discharge pipe. CONSTITUTION:A plurality of cyclone cells 32 are disposed parallel to form a multistage arrangement thereof, being laid one stage on another, wherein dust discharge pipes 46 are connected with each other in a vertical direction. And a cylinder 47 having a thin wall thickness and a smooth inner surface is provided in the dust discharge pipe 46, wherein the outer diameter of said cylinder being in a close engagement with the inner surface of the dust discharge pipe 46 over its whole length, holes 48 being provided on the side wall of the cylinder in such a manner that said holes are continuously connected to the inner surface of the cyclone cell outlet port 38 of the cyclone cell 37. In this manner, amount of ash attaching to the inner surface of the dust discharge pipe can be greatly reduced, so that blocking of dust discharge pipe caused by ash can be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a mechanical dust collector installed in a coal-fired boiler gas recirculation system, or a mechanical dust collector installed in a garbage incinerator, cement mill equipment, or the like.

[Prior Art J An example of the prior art will be explained with reference to FIGS. 2 to 5.

Figure 2 is a diagram of a recirculating gas system in which a conventional mechanical dust collector, that is, a multi-cyclone, is installed; Figure 3 is a side configuration diagram of the multi-cyclone; Figure 4 is a plan view; FIG. 4 shows part a of FIG. 4, that is, a configuration diagram of the multi-cyclone cell main body and the dust discharge pipe section.

In FIGS. 2 to 4, a part of the exhaust gas from the boiler 11 is led to a multi-cyclone 12, where the dust is collected, and then returned to the boiler 11 via a gas recirculation fan 13. Two multi-cyclones 12 are arranged side by side as shown in FIGS. 3 and 4.

This multi-cyclone 12 is provided with two adjacent casings 21, and a multi-cyclone main body 23 is installed inside each of the casings 21. Furthermore, a hopper 22 is provided at the lower end of the casing 21. Casing 2
1, an exhaust gas population 24 is provided at the center of the upper end, and exhaust gas b is introduced.

The clean gas C that has passed through the multi-cyclone main body 23 and has been purified is discharged from a gas outlet 25 provided on the side surface of the casing 21. Further, the collected dust is discharged from the dust outlet 26 of the hopper 22.

As shown in FIG. 5, each cyclone cell 32 has the same shape and includes a cyclone cell main body 37 and a cylindrical dust discharge pipe 36 with a trumpet-shaped socket at the upper end. The cyclone cell outlet 38 at the lower end of the cyclone cell main body 37 is joined to the side wall of the dust discharge pipe 36 at a sufficient inclination angle. As shown in FIG. 5, the multi-cyclone main body 23 has a plurality of cyclone cells 32 of the same shape arranged so that their axes are oblique and the dust discharge pipe 36 at the lower end is vertical. They are arranged in parallel in multiple stages from top to bottom. On the other hand, each dust discharge pipe 36 is vertically cascaded by inserting the lower end of the adjacent upper discharge pipe into the socket 39 at the upper end, and the socket 39 at the uppermost end of n1 is closed.

In the above configuration, the exhaust gas b is supplied to the upper part of each cyclone cell 32 from the exhaust gas population 24 of the casing 21,
The purified clean gas C enters from the upper side wall (not shown) and is discharged from the upper end of the clean gas outlet pipe 33 through the gas outlet 25Y.

Further, the collected dust is collected from the cyclone cell outlet 38 at the lower end into the dust discharge pipe 36, and is discharged from the lowermost end through the dust outlet 26'(E' temperature).

On the other hand, a cleaning coil 34 is inserted into each cyclone cell 32 from the upper end to the cyclone cell outlet, and the upper end is connected to a link mechanism 40, respectively. Further, each link mechanism is connected to vertically provided link drive rods 35.

Dust attached to the inner wall of the clean gas outlet pipe 33 and dust attached to the inner wall of the cyclone cell outlet 38 are removed from the cleaning coil 34 via the link drive rod 35Yjr.
is removed by reciprocating at regular intervals.

(Problem to be Solved by the Invention) After the dust is discharged into the dust discharge pipe 36,
Inside 4! : The dust falls to the hopper 22 with the x force, but when it is discharged by the swirling flow from the cyclone cell 32 or during the falling process, it adheres to the inner wall of the dust discharge pipe 36, and as it grows, the dust Discharge pipe 3
61g! : There was a possibility of blockage.

Blockage of the dust discharge pipe 36 is an important problem that leads to blockage of the cyclone cells located above it.

The adhesion of ash to the inner wall of the dust exhaust pipe is greatly influenced by the connection of the exhaust pipe or the roughness of the inner surface of the exhaust pipe.

The cyclone cell main body 37 is generally made of cast metal, and the dust exhaust pipe 36, which is usually manufactured integrally with the cyclone cell main body 37, is also made of cast metal. Have difficulty. Moreover, since the dust discharge pipe 36 has a connecting structure, discontinuous parts called connecting parts cannot be eliminated.

With the present invention, ash adhesion to the inner surface of the dust exhaust pipe can be significantly improved by installing a thin cylinder inside the dust exhaust pipe without changing the structure of the conventional cyclone cell or dust exhaust pipe. This is what we propose.

[Means to solve the problem]

The present invention takes the following measures to solve the above problems.

In other words, a plurality of cyclone cells 3 are arranged in parallel in multiple stages above and below, and each dust discharge pipe is vertically connected in cascade, and has an outer diameter that closely fits the entire surface of the inner surface of the dust discharge pipe. A thin-walled cylinder having a smooth inner surface and having a hole in its side wall whose inner surface is continuously connected to the cyclone cell outlet of the cyclone cell body is provided in the dust discharge pipe.

[Effect]

By the above means, the inner surface of the dust discharge pipe becomes a smooth surface without any protrusions, so that adhesion of ash is avoided and reliability is greatly improved.

[Example J An example of the present invention will be described with reference to FIG. Note that the portions described in the conventional example will be omitted to avoid redundancy.

Inside the dust discharge pipe 46, there is a thin cylinder 47 that is in close contact with the entire inner surface of the dust discharge pipe and has a smooth surface with little ash adhesion.
'&Installing. Further, a hole 48 is provided in the side wall of the cylinder 47 to smoothly connect with the inner surface of each cyclone cell outlet 38.

In the above configuration, the rough gas flowing tangentially into the cyclone cell 32 generates a swirling flow inside the cyclone cell 32 due to the effect of the clean gas outlet pipe 33, and this folding is caused by centrifugal force. As a result, the dust is discharged to the dust discharge pipe 46, and falls into a part of the hopper below by gravity within the dust discharge pipe 46. On the other hand, the clean gas C from which the ash has been separated is
The clean gas is discharged through the clean gas outlet pipe 33 into the clean gas chamber.

As mentioned above, the separated ash falls through the duct discharge pipe 46, but inside the dust discharge pipe 46 there is a thin cylinder 47 with a smooth surface and less ash adhesion.
Since the ash is attached in close contact with the ash, adhesion of ash to the inner wall surface during the falling process is greatly reduced, and clogging of the dust discharge pipe 46 by ash can be prevented.

Note that the material of the thin-walled cylinder with a smooth surface may be any metal such as carbon steel or stainless steel.

In the manner described above, dust adhesion within the dust discharge pipe can be significantly reduced.

〔Effect of the invention〕

As described above, the present invention provides the following effects.

That is, since the adhesion of ash to the inner wall of the dust discharge pipe can be significantly reduced, ash clogging in the dust discharge pipe can be prevented.

In addition, ash blockage in the discharge pipe section causes blockage of the cyclone cells upstream of the discharge pipe section, but such problems can also be prevented from occurring.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of an embodiment of the present invention, Figure 2 is a recirculation gas system diagram in a conventional coal-fired boiler, and Figure 3 is a diagram of the recirculating gas system in a conventional coal-fired boiler.
FIG. 4 is a plan view of the multi-cyclone shown in FIG. In the figure 11... Boiler 12... Multi cyclone 13... Gas recirculation fan 21... Casing 22... Hopper 23... Multi cyclone body 2
4...Exhaust gas inlet 25...Gas outlet 26...
・Dust outlet 31...Support plate 32...Cyclone cell 33...Clean gas outlet pipe 34...Cleaning coil 35...Link drive rod 36...
Dust discharge pipe 37...Cyclone cell body 38
...Cyclone cell outlet 39...Socket 40...Link mechanism 41...Support plate 42...Cyclone cell 43...Clean gas outlet pipe 44...Cleaning carp A/ 45... Cleaning coil drive device 46...Dust discharge pipe 47...Dust discharge pipe cylinder 48...
hole

Claims (1)

[Claims] In a mechanical dust collector in which a plurality of cyclone cells are arranged vertically in parallel in multiple stages and each dust discharge pipe is vertically connected in cascade, the dust discharge pipe has an outer diameter that closely fits the entire inner surface of the dust discharge pipe, and has an outer diameter that closely fits the entire inner surface of the dust discharge pipe. A mechanical dust collector characterized in that a thin cylinder having a smooth inner surface and having a hole that continuously connects the cyclone cell outlet and the inner surface of the cyclone cell main body is provided in the dust discharge pipe.