JP2012122889A - Gasifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gasifier capable of putting in and out a screw shaft without opening a motor side of a gasifier body and shortening the operation time required for exchanging (or inspecting) the screw shaft.SOLUTION: In a gasifier 10 in which radioactive waste is gasified inside a gasifier body 11 and residues after gasifying the radioactive waste are discharged by a screw shaft 12 rotatably accommodated inside the gasifier body 11, one end part 21a is connected to a rotary motor 13 for driving the screw shaft 12 and other end part 21b is disposed on an intermediate shaft 21 extending from the outside of the gasifier body 11 to the inside of the gasifier body 11, other end part 21b of the intermediate shaft 21 and motor side end part 12a of the screw shaft 12. The gasifier 10 has a connection mechanism 23 for detachably connecting other end part 21b of the intermediate shaft 21 and the motor side end part 12a of the screw shaft 12.

Description

  According to the present invention, radioactive waste is gasified in a process of being conveyed in a screw shaft furnace rotatably accommodated in a gasifier main body, and the residue when the radioactive waste is gasified is discharged by the screw shaft. The present invention relates to a gasifier.

  Radioactive waste from a nuclear power plant, for example, is gasified with a gasifier (steam reformer), the gas content is treated with a detoxifying device and then released into the atmosphere, and the radioactive waste is gasified. The residue is recovered with a residue recovery device. Since the object to be treated is radioactive waste, manual work is limited, and the gasifier is operated by remote operation by a machine.

  FIG. 3 shows a gasifier.

  In the gasifier 40 shown in FIG. 3, radioactive waste is supplied from the supply pipe 41 into the gasifier main body (trough) 42. The radioactive waste supplied to the inside of the gasifier main body 42 is heated and gasified by a heater (not shown) attached to the gasifier main body 42, and the gas content is exhaust gas pipe (not shown). The residue is sequentially discharged from the residue discharge pipe 44 as the screw shaft 43 rotates. The screw shaft 43 is connected to a screw rotation motor 46 by a coupling (motor coupling) 45, and a portion of the gasifier main body 42 through which the screw shaft 43 passes is sealed by a shaft seal mechanism 47.

  The prior art documents related to the background art include the following.

Japanese Patent Laid-Open No. 10-300036

  In the gasifier 40 shown in FIG. 3, when the screw shaft 43 is replaced (or inspected), it is necessary to disconnect the coupling 45 each time before the screw shaft 43 is extracted from the gasifier main body 42. Therefore, the work time required for replacement (or inspection) of the screw shaft 43 tends to be long, and the work time needs to be shortened.

  Further, in the gasifier 40 shown in FIG. 3, when the screw shaft 43 is replaced (or inspected), the motor side of the gasifier main body 42 is opened. In addition, there is a possibility that the surroundings of the gasifier main body 42 may be contaminated.

  Accordingly, an object of the present invention is to provide a gasifier capable of taking in and out the screw shaft without opening the motor side of the gasifier main body and reducing the work time required for replacement (or inspection) of the screw shaft. Is to provide.

  In order to achieve the above object, the present invention provides a screw in which radioactive waste is gasified inside a gasifier main body, and the residue when the radioactive waste is gasified is rotatably accommodated inside the gasifier main body. A gasifier that discharges through a shaft, wherein one end is connected to a rotary motor that drives the screw shaft, and the other end extends from the outside of the gasifier body to the inside of the gasifier body. The intermediate shaft is provided at the other end portion of the intermediate shaft and the motor side end portion of the screw shaft, and the other end portion of the intermediate shaft and the motor side end portion of the screw shaft are inserted. And a connection mechanism that removably connects.

  The coupling mechanism includes a plus-shaped groove portion formed on one of the other end portion of the intermediate shaft and the motor-side end portion of the screw shaft, and a minus shape formed on the other side and inserted into the groove portion. It may be comprised from the convex part.

  According to the present invention, there is provided a gasifier capable of taking in and out the screw shaft without opening the motor side of the gasifier main body and shortening the work time required for replacement (or inspection) of the screw shaft. There is an excellent effect of being able to.

FIG. 1 is a side sectional view of a gasifier according to an embodiment of the present invention. 2 (a) is a side view showing a connecting portion between the intermediate shaft and the screw shaft, FIG. 2 (b) is a view taken along the line AA of FIG. 2 (a), and FIG. It is a BB line arrow directional view of Drawing 2 (a). FIG. 3 is a side sectional view of a gasifier according to a conventional example.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  As shown in FIG. 1, a gasifier (steam reformer device) 10 according to the present embodiment is a low-level radioactive waste treatment device, and a gasifier main body (gasifier) that gasifies the supplied radioactive waste ( Trough) 11 and a screw rotation motor (rotation motor) 13 which is disposed outside the gasifier main body 11 and drives a screw shaft 12 which will be described later.

  The gasifier main body 11 is attached to a cylindrical portion 14 formed in a cylindrical shape (cylindrical in this embodiment) and a bolt 15 at one end (left side in FIG. 1) of the cylindrical portion 14. A first lid 16 that closes the opening on the motor side, and a bolt 17 that is attached to the other end (right side in FIG. 1) of the cylindrical portion 14 and closes the opening on the opposite side of the cylindrical portion 14 from the motor side. And two lids 18. Connected to the cylinder portion 14 are a supply pipe 19 for supplying radioactive waste, an exhaust gas pipe (not shown) for exhausting gas components, and a residue discharge pipe 20 for discharging residues. Yes. In addition, a heater (not shown) for heating the radioactive waste supplied to the inside of the gasifier main body 11 (cylinder part 14) is attached to the outer periphery of the cylinder part 14.

  The screw rotation motor 13 rotates the screw shaft 12 at a relatively low speed (about 1 rpm), and is composed of a hydraulic motor or an electric motor.

  In the present embodiment, an intermediate shaft (motor side shaft) 21 for positioning the screw shaft 12 is provided between the screw shaft (gasifier main body side shaft) 12 and the screw rotation motor 13, and the motor side of the intermediate shaft 21 is provided. The end (one end) 21 a is connected to the screw rotation motor 13 by a coupling (motor coupling) 22, and the gasifier main body side end (other end) 21 b of the intermediate shaft 21 is from the outside of the gasifier main body 11. The screw shaft 12 and the connecting mechanism 23 are provided inside the gasifier main body 11 so as to extend into the gasifier main body 11.

  That is, in the gasifier 10 according to the present embodiment, the motor side end 21a is connected to the screw rotation motor 13 by the coupling 22, and the gasifier main body side end 21b is gas from the outside of the gasifier main body 11. An intermediate shaft 21 extending to the inside of the gasifier main body 11, a screw shaft 12 rotatably accommodated in the gasifier main body 11, and an intermediate shaft so as to discharge residues when the radioactive waste is gasified The gasifier main body side end 21b of the screw shaft 12 and the motor side end 12a of the screw shaft 12 are provided, and the gasifier main body side end 21b of the intermediate shaft 21 and the motor side end 12a of the screw shaft 12 are inserted. And a connecting mechanism 23 for removably connecting.

  The intermediate shaft 21 has a length from the coupling 22 to the inside of the gasifier main body 11. The intermediate shaft 21 is supported by a bearing (in this embodiment, a plummer block) 24 outside the gasifier main body 11, and a portion of the gasifier main body 11 through which the intermediate shaft 21 passes is sealed by a shaft seal mechanism 25. .

  The coupling (in this embodiment, flange-type shaft coupling) 22 includes a motor-side flange 27 attached to the tip of the rotary shaft 26 of the screw rotary motor 13 and an intermediate portion attached to the motor-side end 21 a of the intermediate shaft 21. The motor side flange 27 and the intermediate shaft side flange 28 are connected by a bolt 29.

  The shaft seal mechanism 25 is fixed to the first lid 16 of the gasifier main body 11 and has a cylindrical boss portion 30 through which the intermediate shaft 21 is inserted, and a gap between the inner periphery of the boss portion 30 and the outer periphery of the intermediate shaft 21. And a packing presser 33 attached to the boss portion 30 with bolts 32.

  The screw shaft 12 is a part that is frequently taken in and out of the gasifier main body 11 by replacement (or inspection) or the like. The screw shaft 12 includes a shaft portion 34 extending in the longitudinal direction of the gasifier main body 11, a pair of end plates 35 mounted at intervals in the longitudinal direction of the shaft portion 34, and a space between the pair of end plates 35. And a screw 36 mounted on the shaft portion 34.

  As shown in FIG. 2, the coupling mechanism 23 is formed in a plus-shaped groove portion 37 formed at the motor-side end portion 12 a of the screw shaft 12 and a gasifier main body-side end portion 21 b of the intermediate shaft 21. This is a simple key coupling mechanism composed of a minus-shaped convex portion 38 inserted into the. In the present embodiment, the width W <b> 1 of the groove portion 37 is slightly larger than the width W <b> 2 of the convex portion 38.

  Next, the operation of this embodiment will be described.

  In the gasifier 10 shown in FIG. 1, radioactive waste is supplied into the gasifier main body 11 from the supply pipe 19. Then, the radioactive waste supplied into the gasifier main body 11 is heated and gasified by a heater attached to the gasifier main body 11, the gas component is exhausted from the exhaust gas pipe, and the residue is discharged from the screw shaft 12. With the rotation, the residue is sequentially discharged from the residue discharge pipe 20.

<Removal of screw shaft>
The 2nd cover 18 is removed from the cylinder part 14 of the gasifier main body 11, and the opposite side to the motor side of the gasifier main body 11 is open | released. And the screw shaft 12 can be extracted from the gasifier main body 11 by pulling the screw shaft 12 as it is to the opposite side to the motor side.

<Screw shaft connection>
The screw shaft 12 is inserted from the side opposite to the motor side of the gasifier main body 11. When the screw shaft 12 reaches the vicinity of the stroke end, the screw shaft 12 is pushed to the motor side while the screw rotation motor 13 is driven and the intermediate shaft 21 is rotated. It is detected at the moving position of the screw shaft 12 that the convex portion 38 of the coupling mechanism 23 (the gasifier main body side end 21b of the intermediate shaft 21) has entered the groove 37 (the motor side end 12a of the screw shaft 12) to the end. To do. Specifically, when the screw shaft 12 moves to a position where the tip of the end portion 12b opposite to the motor-side end portion 12a of the screw shaft 12 is within the cylindrical portion 14 of the gasifier main body 11, the connection mechanism It is determined that the 23 convex portions 38 have entered the groove portion 37 to the end. When the convex portion 38 of the coupling mechanism 23 does not enter the groove portion 37 to the end, the operation of pushing the screw shaft 12 to the motor side is repeatedly performed while the screw rotation motor 13 is driven and the intermediate shaft 21 is rotated. Then, if it is detected at the movement position of the screw shaft 12 that the convex portion 38 of the coupling mechanism 23 has entered the groove portion 37, the second lid 18 is attached to the cylindrical portion 14 of the gasifier main body 11, and the gas The apparatus main body 11 is sealed.

  In this embodiment, since the screw shaft 12 is connected by the connecting mechanism 23 in the gasifier main body 11, it is not necessary to disconnect the coupling 22 every time the screw shaft 12 is replaced (or inspected). And the screw shaft 12 is connected by a connecting mechanism 23 that removably connects the gasifier main body side end portion 21b of the intermediate shaft 21 and the motor side end portion 12a of the screw shaft 12. The work time required for replacement (or inspection) can be shortened.

  Moreover, in this embodiment, since the connection part (connection mechanism 23) of the screw shaft 12 exists in the gasifier main body 11, it becomes unnecessary to open | release the motor side of the gasifier main body 11, and the gasifier main body 11 of FIG. The radioactive waste is not scattered to the motor side.

  Therefore, according to the gasifier 10 according to the present embodiment, the screw shaft 12 can be taken in and out without opening the motor side of the gasifier main body 11, and work required for replacement (or inspection) of the screw shaft 12 Reduction of time and radiation exposure to workers during coupling connection work can be eliminated.

  In the present embodiment, the coupling mechanism 23 is formed at the plus-shaped groove portion 37 formed at the motor-side end portion 12 a of the screw shaft 12 and the gasifier main body-side end portion 21 b of the intermediate shaft 21. When the intermediate shaft 21 is rotated by a maximum of 90 degrees, the convex portion 38 can be inserted into the groove portion 37, and the groove portion 37 is formed in a negative shape. The screw shaft 12 can be connected in a short time as compared with (necessary to rotate the intermediate shaft 21 at a maximum of 180 degrees).

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various other embodiments can be adopted.

  For example, in the above-described embodiment, the plus-shaped groove portion 37 is formed at the motor-side end portion 12a of the screw shaft 12, and the minus-shaped convex portion 38 is formed at the gasifier main body-side end portion 21b of the intermediate shaft 21. However, instead of this, a plus-shaped groove 37 may be formed in the gasifier main body side end 21b of the intermediate shaft 21, and a minus-shaped convex portion 38 may be formed in the motor-side end 12a of the screw shaft 12. good. That is, a plus-shaped groove 37 is formed on one of the gasifier main body side end 21b of the intermediate shaft 21 and the motor-side end 12a of the screw shaft 12, and a minus-shaped convex portion 38 is formed on the other. It ’s fine.

10 Gasifier (Steam reformer)
11 Gasifier body (trough)
12 Screw shaft 12a Motor side end 13 Screw rotation motor (rotation motor)
21 Intermediate shaft 21a Motor side end (one end)
21b Gasification device body side end (other end)
23 connecting mechanism 37 groove 38 convex

Claims (2)

This is a gasification device in which radioactive waste is gasified inside the gasifier main body, and the residue when the radioactive waste is gasified is discharged by a screw shaft rotatably accommodated inside the gasifier main body. And
An intermediate shaft having one end connected to a rotary motor that drives the screw shaft and the other end extended from the outside of the gasifier main body to the inside of the gasifier main body,
A connecting mechanism that is provided at the other end of the intermediate shaft and a motor side end of the screw shaft and removably connects the other end of the intermediate shaft and the motor side end of the screw shaft. And a gasifier characterized by comprising:   The coupling mechanism includes a plus-shaped groove portion formed on one of the other end portion of the intermediate shaft and the motor-side end portion of the screw shaft, and a minus shape formed on the other side and inserted into the groove portion. The gasifier of Claim 1 comprised from these convex parts.