JP2008256287A - Seal device of rotary kiln - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal device of a rotary kiln capable of surely sealing without allowing the air to flow into a carbonization kiln, even when the rotary kiln is used as carbonization equipment. <P>SOLUTION: This seal device between an end peripheral face of a rotating drum of the rotary kiln and a fixed member disposed on a position opposed to the end peripheral face, has a ring-shaped seal plate circularly disposed on the end peripheral face of the rotating drum, a ring-shaped pressing plate disposed on a position opposed to the seal plate and mounted on the fixed member, and a ring-shaped packing member disposed between the seal plate and the pressing plate, and slidable to a sliding face of the pressing plate. The packing ring is composed of a double ring having an annular space between the rings, and inert gas exists in the annular space in a positive pressure state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a rotary kiln sealing device, and more specifically, a sealing device between an end peripheral surface of a rotary drum of a rotary kiln used as a carbonization furnace and a fixing member disposed at a position facing the end peripheral surface. It is about.

  An indirect heating type rotary kiln is configured such that when a raw material is charged into a rotating drum as a rotating unit and the rotating drum is rotated, the raw material is transferred from the inlet side to the outlet side while being stirred, and the rotating drum is being transferred. This is a device that heats the interior by indirect heating, for example, from a jacket provided on a rotating drum. In this case, there is a gap between the peripheral surface of the rotating drum and the fixing member disposed at a position facing the peripheral surface of the rotating drum, and it is necessary to seal this gap.

Therefore, various types of sealing devices have been used conventionally. For example, a sealing device that blows air onto the joint surface between the rotating portion and the non-rotating portion (conventional technology 1), or a sliding metal ring on the non-rotating portion. There has been used a sealing device (referred to as Prior Art 2) which seals the metal ring by bringing it into contact with a gland packing made of carbon fiber and attached to a rotating drum.
Further, Patent Document 1 discloses an annular seal box containing a sealing plate in a portion through which the cylinders at both ends of the heating furnace pass as a sealing device for a carbonized kiln used in a heating furnace, and a pressure higher than that in the heating furnace is provided in this box. A sealing device is disclosed that prevents the blowing of flame from the heating furnace by pumping the air or inert gas.
Patent Document 2 discloses a seal member formed in an annular shape between a flange-shaped mounting plate formed around the outer periphery of a rotating drum and a hollow annular pressing plate extending from a fixed cover case via a bellows. A sealing device that seals the inside and outside of a rotary kiln and is provided with pressure control means between a fixed cover case and a pressing plate is disclosed.

JP-A-53-56167 JP 2003-75069 A

  However, in the prior art 1, since the blown air flows into the rotary drum constituting the rotary kiln, it cannot be employed as a sealing device when the rotary kiln is used as a carbonization furnace. Moreover, the end part peripheral surface of the rotary drum of the rotary kiln which uses any sealing device of the prior art 2, patent document 1, and patent document 2 as a carbonization furnace, and the fixing member distribute | arranged to the position facing this end part peripheral surface Even when used as a sealing device, the pyrolysis gas generated in the rotary kiln penetrates into the gland packing and solidifies, so that the gland packing loses flexibility and the gland packing is rapidly deteriorated. Furthermore, by using a gland packing in which pyrolysis gas penetrates and solidifies and loses flexibility, there is a problem that even the metal ring that is a sliding partner of the gland packing is worn and the sealing performance is lowered.

  Accordingly, in view of the problems of the prior art, the present invention has an object of providing a rotary kiln sealing device capable of reliably sealing air even when used as a carbonization facility in a rotary kiln without air flowing into the carbonization kiln. To do.

In order to solve the above problems, in the present invention,
In a sealing device between an end peripheral surface of a rotary drum of a rotary kiln and a fixing member disposed at a position facing the end peripheral surface, a ring-shaped seal provided around the rotary drum end peripheral surface A plate, a ring-shaped pressing plate that is disposed at a position facing the sealing plate and attached to the fixing member, and is interposed between the sealing plate and the pressing plate, and can slide on the sliding surface of the pressing plate. A ring-shaped packing member, and the packing member is a double ring having an annular space between the rings, and an inert gas is present in the annular space in a positive pressure state.

  A ring-shaped packing member between a ring-shaped seal plate provided around the peripheral surface of the rotating drum and a ring-shaped pressing plate disposed at a position facing the seal plate and attached to the fixing member Between the end peripheral surface of the rotary drum and the fixing member disposed at a position facing the end peripheral surface by sliding the ring-shaped packing member and the pressing plate sliding surface. Can be sealed.

  Furthermore, when the packing member is constituted by a double ring having an annular space between the rings, and the inert gas is present in the annular space in a positive pressure state, the pyrolysis gas inside the rotating drum flows out to the outside. In addition, the outside air can be prevented from flowing into the rotating drum, and the sealing performance can be improved. Further, since it is possible to prevent the pyrolysis gas in the rotating drum from penetrating into the packing member, the pyrolysis gas penetrates into the packing member and solidifies, and the packing member loses its flexibility and the accompanying gland. Deterioration of the packing can be prevented.

  The pressing plate is supported by a pressing plate support member attached to the fixing member, and a gas passage for introducing an inert gas into the annular space is provided in the pressing plate and the pressing plate support member. Features. As a result, an inert gas introduction passage can be provided in a space-saving manner.

  Moreover, the sealing performance is further improved by biasing the pressing force in the packing member pressing direction from the back side of the pressing plate via the pressing plate support member.

  Further, the packing member is a gland packing in which carbon fibers are knitted, and the gland packing is impregnated with a fluororesin. Since the packing made of carbon fiber has a very small coefficient of friction, the sealing performance can be maintained for a long time. Furthermore, by impregnating the gland packing with the fluororesin, it is possible to prevent the pyrolysis gas from penetrating into the gland packing by closing the gap between the carbon fibers with the fluororesin.

  As described above, according to the present invention, it is possible to provide a rotary kiln sealing device capable of reliably sealing air even when used as a carbonization facility in a rotary kiln without causing air to flow into the carbonized kiln.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.

  In order to produce carbides, carbonization furnaces are mainly used, and for example, combustible solids containing volatile components such as biomass and fixed carbon components are introduced into the carbonization furnace and heated to contain a large amount of fixed carbon components. Carbide can be obtained.

  FIG. 1 is a schematic configuration diagram showing an example of a carbide production facility for producing carbide. In FIG. 1, reference numeral 1 denotes a carbonized kiln. The carbonized kiln 1 includes a rotary drum 2, an outer cylinder 3 whose inner peripheral surface is covered with a refractory material 4, an outer peripheral surface of the rotary drum 2, and an inner peripheral surface of the refractory material 4. It is mainly comprised from the heating chamber 5 formed between. 6 is a raw material supply hopper, 7a and 7b are raw material slide gates that can open and close the passage of the raw material supply hopper 6, 8 is a raw material supply conveyor, 9 is a carbide discharge chute, 10 is a pyrolysis cyclone, and 11 is a combustion chamber. , 13 is an emergency discharge device.

  In such a carbide manufacturing apparatus, whether the supply amount of combustible solids containing volatile components such as biomass and fixed carbon components supplied to the raw material hopper 6 and fixed carbon components is controlled using the raw material slide gates 7a and 7b. Alternatively, when it is difficult to control the supply amount with the raw material slide gates 7a and 7b, the combustible solids whose supply amount is controlled in advance are supplied into the rotary drum 2 constituting the carbonization furnace 1 with the raw material supply conveyor 8. .

  The rotating drum 2 is provided with an outer cylinder 3 whose inner peripheral surface is covered with a refractory material 4 on the outer periphery of a portion other than both ends, and between the outer peripheral surface of the rotating drum 2 and the inner peripheral surface of the refractory material 4. A heating chamber 5 is formed. The inside of the rotating drum 2 is heated by passing a heating medium such as combustion gas through the heating chamber 5 and transferring the heat to the rotating drum 2.

  The raw material supplied into the rotary drum 2 from the raw material supply conveyor 8 is transferred while being stirred from the raw material supply conveyor 8 side to the carbide discharge chute 9 side when the rotary drum 2 rotates, It is heated by indirect heating from the heating chamber 5 and carbonized to become carbide and discharged from the carbide discharge chute 9 to a subsequent process.

  The pyrolysis gas generated during the production of carbide by carbonizing the raw material with the carbonized kiln 1 is solid-gas separated by the pyrolysis cyclone 10 and then sent to the combustion chamber 11 where the pyrolysis gas in the pyrolysis gas Combustible matter burns. The combustion gas that has been subjected to solid-gas separation and combustible combustion in the pyrolysis cyclone 10 and the combustion chamber 11 in this way is sent to the boiler through the exhaust gas duct 12 and effectively used as a heat source.

  In addition, an emergency discharge device 13 is provided in the exhaust gas duct 12 in order to release the pressure to the atmosphere and prevent the combustible gas from leaking outside the system when the inside of the combustion chamber 11 becomes an abnormally high pressure. Yes.

  In such a carbide manufacturing facility, there is a gap between the end peripheral surface of the rotary drum 2 and a fixing member disposed at a position facing the end peripheral surface of the rotary drum 2, and this gap is sealed. Thus, it is important to prevent leakage of pyrolysis gas inside the rotary kiln 1 from the gap and inflow of outside air into the rotary kiln 1.

  FIG. 2 is a configuration diagram around the rotary kiln 1. As described above, the rotary kiln 1 includes the rotary drum 2, the outer cylinder 3 whose inner peripheral surface is covered with the refractory material 4, and the heating chamber formed between the outer peripheral surface of the rotary drum 2 and the inner peripheral surface of the refractory material 4. Mainly composed of five. The rotating drum 2 has a rotating drum outer cylinder 21 and a rotating drum inner cylinder 22 at the end. A space between the outer cylinder 3 and the rotating drum outer cylinder 21 is sealed with a muffle air seal 30 so that the heating medium in the heating chamber 5 does not flow out and the outside air does not flow into the heating chamber 5.

  Furthermore, the clearance gap between the edge part surrounding surface of the rotating drum inner cylinder 22 of the rotating drum 2, and the raw material supply conveyor 8 which is a fixing member arrange | positioned in the position facing the edge part surrounding surface of this rotating drum inner cylinder 22 Is sealed with a kiln air seal 20. Similarly, a gap between the end peripheral surface of the rotary drum inner cylinder 22 of the rotary drum 2 and the carbide discharge chute 9 that is a fixing member disposed at a position facing the end peripheral surface of the rotary drum inner cylinder 22. Is sealed with a kiln air seal 20.

FIG. 3 is a sectional view of the kiln air seal 20. Hereinafter, a kiln air seal is demonstrated using FIG.2 and FIG.3.
The kiln air seal 20 includes a seal plate 207 provided around the end peripheral surface of the rotary drum inner cylinder 22, a ring-shaped pressing plate 205 attached to a bearing system 210 (fixing member), and the seal plate 207 and the pressing plate. It is mainly composed of a double ring-shaped gland packing 206 interposed between the plates 205.

  When the rotary drum 2 (rotary drum inner cylinder 22) rotates, the seal plate 207 provided around the rotary drum inner cylinder 22 rotates as the rotary drum inner cylinder 22 rotates, and the gland packing 206 further includes the seal plate 207. And rotate together with the seal plate 207. At this time, the gland packing 206 and the sliding surface 206a of the pressing plate 205 are sealed by sliding. In order to improve the sealing performance, the pressing plate 205 is urged toward the gland packing 206 by the spring 204.

  At this time, the rotating drum outer cylinder 21 is fixed by a bolt 212 to a bearing system 210 which is a fixing member provided at a position where the bearing 202 provided at the end of the rotating drum outer cylinder 21 faces the rotating drum outer cylinder 21. It rotates by being supported by the member 211 and rotating.

  Further, as a characteristic feature of the present invention, the gland packing 206 is a double ring, and an annular space 206b is provided between the inner ring and the outer ring of the double ring. Furthermore, a gas passage 220 capable of introducing nitrogen gas into the annular space 206b is provided in the holding plate 205, and nitrogen gas can be introduced into the annular space 206b from the outside in a positive pressure state.

  FIG. 4 is a cross-sectional view of the pressing plate 205. The shape of the gas passage 220 in the holding plate 205 may be a plurality of through holes 205a provided at equal intervals as shown in FIG. 4 (A), or a ring-shaped through hole as shown in FIG. 4 (B). The groove 205b may be used. Further, it is only necessary that nitrogen gas can be introduced even if the shape is other than those shown in FIGS. 4 (A) and 4 (B).

Thus, by introducing nitrogen gas into the annular space 206b in a positive pressure state, it is possible to prevent the pyrolysis gas inside the rotating drum 2 from flowing out and the outside air from flowing into the rotating drum 2. The sealing performance is improved.
Further, by introducing nitrogen gas into the annular space 206b in a positive pressure state, it is possible to prevent the pyrolysis gas in the rotary drum 2 from penetrating into the gland packing 206. It penetrates into the inside and solidifies, so that the packing member loses its flexibility and the accompanying deterioration of the gland packing is prevented.

  In this embodiment, the gas introduced into the annular space 206b is nitrogen gas. However, any gas may be used as long as it is an inert gas. This is because if it is an inert gas, even if it flows into the rotating drum 2 through the gland packing 206 or the sliding surface 206a, carbonization in the rotating drum 2 is not affected.

  Further, the gland packing 206 is a carbon fiber gland packing impregnated with Teflon (registered trademark). Since the packing made of carbon fiber has a very small coefficient of friction, the sealing performance can be maintained for a long time. Furthermore, by impregnating the gland packing with the fluororesin, it is possible to prevent the pyrolysis gas from penetrating into the gland packing by closing the gap between the carbon fibers with the fluororesin. Such a carbon fiber gland packing impregnated with Teflon (registered trademark) can improve the sealing performance when it is used as a seal packing in a portion where pyrolysis gas may flow in addition to 20 parts of the kiln air seal.

  Furthermore, a nickel paste is applied to the surface of the gland packing 206. Thus, the nickel paste serves as a lubricant for the sliding surface 206 a and also serves as a surface protective agent for the gland packing 206.

  Even when used as a carbonization facility in a rotary kiln, it can be used as a sealing device for a rotary kiln capable of reliable sealing without air flowing into the carbonization kiln.

It is a schematic structure figure showing an example of carbide manufacture equipment for manufacturing a carbide. It is a block diagram around a rotary kiln. It is sectional drawing of a kiln air seal. 3 is a cross-sectional view of a pressing plate 205.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbide kiln 2 Rotating drum 8 Raw material supply conveyor 9 Carbide discharge chute 20 Kiln air seal 21 Rotating drum outer cylinder 22 Rotating drum inner cylinder 203 Fixed plate 204 Spring 205 Press plate 206 Gland packing 207 Seal plate 209 Press plate support member 220 Gas passage

Claims (4)

In a sealing device between an end peripheral surface of a rotary drum of a rotary kiln and a fixing member disposed at a position facing the end peripheral surface,
A ring-shaped seal plate provided around the peripheral surface of the rotating drum;
A ring-shaped pressing plate disposed at a position facing the seal plate and attached to the fixing member;
It is interposed between the seal plate and the pressing plate, and has a ring-shaped packing member that can slide with the pressing plate sliding surface,
The packing device is constituted by a double ring having an annular space between the rings, and an inert gas is present in the annular space in a positive pressure state. The pressing plate is supported by a pressing plate support member attached to the fixing member,
The sealing device according to claim 1, wherein a gas passage for introducing an inert gas into the annular space is provided in the pressing plate and the pressing plate support member.   The sealing device according to claim 2, wherein a pressing force is urged in a packing member pressing direction from a back side of the pressing plate via the pressing plate support member.   The sealing device according to any one of claims 1 to 3, wherein the packing member is a gland packing in which carbon fibers are knitted, and the gland packing is impregnated with a fluororesin.

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