JP3148114B2 - Shaft seal structure of high temperature powder agitator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft seal structure of a high-temperature powder stirrer such as a reactor for thermally decomposing dioxins by heating and stirring fly ash.

[0002]

2. Description of the Related Art Conventionally, a stirrer for stirring powder usually includes:
A grease seal is used because it easily leaks from the shaft seal. This grease seal forms a seal groove that fills grease between the shaft and the inside of the shaft seal case that has a cland packing that slides on the shaft.The grease is always filled in the seal groove from an external grease filling machine. That's what you'll let me do.

However, when the powder is heated to a high temperature as in a reactor for thermally decomposing fly ash dioxins,
A grease seal cannot be used because the grease may burn. For this reason, a seal structure in which a labyrinth was provided inside the cland packing was implemented.

[0004]

However, this stirrer has a long rotating shaft arranged in the lateral direction, and the rotating shaft is bent due to stirring resistance, thermal deformation, shaft bending and the like. It is necessary to form a gap between the labyrinth and the shaft seal case to allow this bending, but the powder immediately reaches the cland packing through this gap, and only the gland packing becomes a seal. Was a problem.

According to the first aspect of the present invention, there is provided a shaft seal structure of a high-temperature powder stirrer which solves the above-mentioned problems, is excellent in heat resistance, can cope with shaft displacement, and can secure sealing performance. The purpose is to provide.

[0006]

In order to achieve the above object, the invention according to claim 1 of the present invention provides a high-temperature powder for sealing a through portion of a rotary shaft for stirring of a casing for stirring high-temperature powder. A shaft seal structure of the stirrer, in which a plurality of metal ring-shaped seal plates which are slidably fitted in the axial direction on the rotating shaft are fitted inside a gland packing provided in the shaft seal case at a predetermined interval. A seal groove is formed in the shaft seal case so that the outer peripheral portion of the seal plate fits into the shaft seal case, and the seal groove is formed on both sides such that the inner surface and the outer surface of the seal plate are in sliding contact with each other. A gap is formed between the bottom of the seal groove and the outer peripheral edge of the seal plate to allow radial displacement of the rotating shaft.

According to a second aspect of the present invention, the shaft seal case is divided into two parts along a plane passing through the axis of the rotating shaft so as to be assembled and disassembled, and the seal plate is divided into two parts in the diameter direction. It is.

According to the above construction, the axial displacement due to the deflection of the rotating shaft during stirring is allowed by sliding the seal plate in the axial direction relative to the rotating shaft, and the displacement in the radial direction is allowed. This can be tolerated by the fact that the seal plate slides on the side surface of the seal groove and retreats to the gap side. The sliding contact between the rotating shaft and the center hole of the ring plate and the sliding contact between the seal plate and both side surfaces of the seal groove can prevent powder leakage, and furthermore, the gas seal can be prevented by the gland packing. Can be secured.

Further, by dividing the shaft seal case and the seal plate into two parts, maintenance and replacement can be performed easily and in a short time.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a high-temperature powder stirrer provided in a fly ash processing facility according to the present invention will be described with reference to the drawings.

As shown in FIG. 4, a reactor 1 which is an example of a high-temperature powder stirrer is provided in a fly ash treatment facility for detoxifying fly ash collected from exhaust gas discharged from a refuse incinerator. The collected fly ash is thrown into the casing 4 of the reactor 1 from the fly ash hopper 2 via the rotary valve 3 having a seal structure. A horizontal rotating shaft 6 is rotatably supported in the casing 4 via a shaft seal portion 5A and a bearing 5B according to the present invention.
The rotating shaft 6 is provided with a stirring blade 7. Then, about 350 to 40 is provided by the heater 8 provided in the casing 4.
While being heated to 0 ° C., the rotating shaft 6 is rotated at a low speed by the stirring motor 9 and the fly ash is stirred by the stirring blades 7,
Further, the gas supply device 10 fills the casing 4 with nitrogen gas which is an inert gas. As described above, the fly ash is heated and stirred at a high temperature in a state of insufficient air, and is kept for 2 to 3 hours, whereby harmful dioxins contained in the fly ash are thermally decomposed. After the processing time elapses, the fly ash is sent to a cooler 11 where it is cooled, and then sent to a hopper 13 or a heavy metal stabilizing device via a rotary valve 12 having a seal structure to be discharged.

As shown in FIGS. 1 to 3, the shaft seal portion 5A is formed by dividing a shaft seal case 21 provided at both ends of the casing 4 into two planes through which the axis passes.
1a can be assembled and disassembled by fasteners 22 such as bolts and nuts. Cland packing 23 is disposed outside the shaft seal case 21 in sliding contact with the rotating shaft 6, and three ring-shaped seal plates 24 for preventing fly ash from reaching the cland packing 23 are provided inside the cland packing 23. They are arranged at intervals. These seal plates 24 are made of metal and have a central hole 24a which is slidably fitted in the rotating shaft 6 in the axial direction in a heated high temperature state.
It is divided into two by a dividing line 24e along the diametrical direction, and the divided surfaces are arranged so as to be in contact with each other.

In the shaft seal case 21, a seal groove 25 is formed on an inner peripheral surface 21b corresponding to the seal plate 24 via a hollow portion 27, in which an outer peripheral portion of the seal plate 24 is fitted. The seal grooves 25 are formed on the side surfaces 25a, 25b.
Are in sliding contact with the inner surface 24b and the outer surface 24c of the seal plate 24 in a high temperature state, and the gap between the bottom surface 25c and the outer peripheral edge 24d of the seal plate 24 is allowable to allow the displacement of the seal plate due to the runout of the rotating shaft 6. 26 are formed.

In the above structure, during the heating and stirring of the fly ash,
Even when the rotating shaft 6 is deflected due to the load by the rotating blades 7 or the thermal deformation of the rotating shaft 6, the seal plate 24 slides on the rotating shaft 6 through the center hole 24a, and further the seal plate 24 The inner surface 24b and the outer surface 24c of the
5a and 25b can be absorbed by sliding to the gap 26 side by sliding. Then, it is possible to prevent the fly ash from leaking at the respective sliding contact surfaces.

Therefore, according to the shaft seal portion 5A, the fly ash is prevented from leaking at each sliding contact surface, so that the fly ash does not reach the gland packing 23 and the inside of the high temperature nitrogen gas Leakage can be prevented, and the rotating shaft 6 can be smoothly sealed. Seal plate 2
4 and the seal case 21 are each divided into two parts, so that maintenance and replacement of the shaft seal portion 5A can be easily performed in a short time.

[0016]

As described above, according to the first aspect of the present invention, the displacement of the rotating shaft due to the vibration at the time of agitation is caused by the fact that the seal plate externally fitted to the rotating shaft slides in the axial direction.
This can be tolerated by the gap formed between the bottom of the seal groove at the outer periphery of the seal plate. And the powder seal,
The sliding contact between the rotating shaft and the center hole of the ring plate, and the sliding contact between the inner and outer surfaces of the seal plate and both side surfaces of the seal groove prevent powder leakage, and ensure gas sealability with cland packing. can do. Also, it does not burn at a high temperature unlike an oil seal and has excellent heat resistance.

Further, by dividing the shaft seal case and the seal plate into two, maintenance and replacement can be performed easily and in a short time.

[Brief description of the drawings]

FIG. 1 is a half side view of a shaft seal portion, showing an embodiment of a high-temperature powder stirrer according to the present invention.

FIG. 2 is an enlarged sectional view of the seal plate shown in FIG.

FIG. 3 is a sectional view taken along the line AA shown in FIG. 1;

FIG. 4 is a configuration diagram of fly ash processing equipment provided with the high-temperature powder stirrer.

[Explanation of symbols]

 Reference Signs List 1 reactor (high-temperature powder stirrer) 10 casing 21 shaft seal case 21a flange portion 22 fastener 23 gland packing 24 seal plate 24a center hole 24b inner surface 24c outer surface 24d outer peripheral edge 24e parting line 25 seal groove 25a side surface 25b side surface 25c bottom surface 26 gap

──────────────────────────────────────────────────続 き Continued on the front page (56) References JP-A 4-128205 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16C 33/74 F16J 15/54

Claims (2)

(57) [Claims] 1. A shaft sealing structure of a high-temperature powder stirrer for sealing a penetrating portion of a rotary shaft for stirring of a casing for stirring a high-temperature powder, wherein a gland packing provided inside the shaft seal case is provided. A plurality of metal ring-shaped seal plates which are slidably fitted to the rotating shaft in the axial direction are arranged at predetermined intervals, and the outer peripheral portions of the seal plates are fitted to the shaft seal case. A groove is formed, and the seal groove is formed on both sides such that the inner surface and the outer surface of the seal plate are in sliding contact with each other, and the radial displacement of the rotating shaft is defined between the bottom of the seal groove and the outer peripheral edge of the seal plate. A shaft seal structure for a high-temperature powder stirrer, wherein an allowable gap is formed. 2. The high-temperature high-temperature apparatus according to claim 1, wherein the shaft seal case is divided into two parts by a plane passing through the axis of the rotating shaft so as to be assembled and disassembled, and the seal plate is divided into two parts in the diameter direction. Shaft seal structure of powder agitator.