Carbonization furnace for manufacturing carbon fiber bundle and method for manufacturing carbon fiber bundle

Patent metadata

Field	Value
Publication number	US-9267080-B2
Application number	US-201314411298-A
Country	US
Kind code	B2
Filing date	Jun 21, 2013
Priority date	Jun 27, 2012
Publication date	Feb 23, 2016
Grant date	Feb 23, 2016

Abstract

Provided is a carbonization furnace in which disordering of fiber bundles does not occur and there is no lack of uniformity throughout the entire furnace interior, even in the supply of heated inert gas. A carbonization furnace for manufacturing carbon fiber bundles, the furnace being provided with a heat treatment chamber, an inlet sealed chamber and an outlet sealed chamber, a gas spray nozzle, and a conveyance path, wherein: the gas spray nozzle ( 4 ) has a double tube structure obtained from a hollow cylindrical inner tube ( 8 ) and a hollow cylindrical outer tube ( 7 ), and is disposed in a direction that is horizontal and is orthogonal to the fiber bundle conveyance direction; in the outer tube, multiple gas-spraying holes ( 7 a ) are disposed across the width of the conveyance path in the longitudinal direction of the outer tube, and the area of the gas-spraying holes of the outer tube is 0.5 mm2 to 20 mm2; in the inner tube, multiple gas-spraying holes ( 8 a ) are disposed across the width of the conveyance path in the longitudinal direction of the inner tube such that the gas-spraying directions of the gas-spraying holes are in two or more directions of the circumferential direction of the inner tube, and the interval of the gas-spraying holes of the inner tube in the longitudinal direction of the inner tube is 300 mm or less.

First claim

The invention claimed is:

1. A carbonization furnace for manufacturing a carbon fiber bundle comprising:
a heat treatment chamber for heating a fiber bundle which has a fiber bundle inlet and a fiber bundle outlet through which the fiber bundle is introduced and withdrawn and is filled with an inert gas;
an inlet sealing chamber and an outlet sealing chamber for sealing the gas in the heat treatment chamber which are arranged to be adjacent to the fiber bundle inlet and the fiber bundle outlet of the heat treatment chamber, respectively;
a gas jetting nozzle provided on at least one of the inlet sealing chamber and the outlet sealing chamber; and
a conveying path for conveying the fiber bundle which is provided in the horizontal direction in the inlet sealing chamber, the heat treatment chamber, and the outlet sealing chamber, wherein
the gas jetting nozzle has a double tube structure consisting of a hollow tubular inner tube and a hollow tubular outer tube and is disposed in a direction orthogonal and horizontal to a conveying direction of the fiber bundle, wherein
a plurality of gas jetting holes are disposed on the outer tube in a longitudinal direction of the outer tube over the length corresponding to a width of the conveying path, and a hole area of the gas jetting holes of the outer tube is 0.5 mm 2 or more and 20 mm 2 or less, and
a plurality of gas jetting holes are arranged on the inner tube in a longitudinal direction of the inner tube over the length corresponding to a width of the conveying path and a gas jetting direction of the gas jetting holes is arranged in two or more directions of a circumferential direction of the inner tube, and a hole interval between the gas jetting holes of the inner tube in the longitudinal direction of the inner tube is 300 mm or less.

2. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein a ratio (L/D) of a flow path length (L) of a plurality of gas jetting holes of the outer tube to a longest hole length (D) of the gas jetting holes is 0.2 or more.

3. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein a hole interval of a plurality of gas jetting holes in a longitudinal direction of the outer tube is 100 mm or less.

4. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein a plurality of gas jetting holes of the outer tube are arranged in a longitudinal direction of the outer tube over the length corresponding to a width of the conveying path at equal intervals.

5. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein each hole area of a plurality of gas jetting holes of the inner tube is 50 mm 2 or less.

6. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein a plurality of gas jetting holes of the inner tube are arranged in a longitudinal direction of the inner tube over the length corresponding to a width of the conveying path at equal intervals.

7. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein a plurality of gas jetting holes of the outer tube are arranged in a direction in which an inert gas is not jetted out toward the fiber bundle.

8. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein a plurality of gas jetting holes having the same shape and dimension are arranged on the outer tube and a plurality of gas jetting holes having the same shape and dimension are arranged on the inner tube.

9. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein a plurality of gas jetting holes of the outer tube and a plurality of gas jetting holes of the inner tube are respectively disposed at positions where a gas jetting direction of the gas jetting holes of the inner tube and a gas jetting direction of the gas jetting holes of the outer tube are not overlapped at all.

10. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein either or both of the inlet sealing chamber and the outlet sealing chamber have a labyrinth structure having a throttling piece arranged in a conveying direction of the fiber bundle with a regular interval.

11. The carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein either or both of the inlet sealing chamber and the outlet sealing chamber have one or more pairs of the gas jetting nozzles disposed at positions facing each other in a vertical direction by sandwiching the fiber bundle.

12. A method for manufacturing a carbon fiber bundle comprising a process of heat treating the fiber bundle by the carbonization furnace for manufacturing a carbon fiber bundle according to claim 1 , wherein
in the process, an inert gas at from 200 to 500° C. is supplied to an inner tube of the gas jetting nozzle and the inert gas is jetted out through a plurality of gas jetting holes of an outer tube so that a temperature difference in a width direction of either or both of the inlet sealing chamber and the outlet sealing chamber which are equipped with the gas jetting nozzle is 8% or less.

13. The method for manufacturing a carbon fiber bundle according to claim 12 , wherein an inert gas is jetted out through the gas jetting nozzle at a flow rate per 1 m in a longitudinal direction of the gas jetting nozzle of 1.0 Nm 3 /hr or more and 100 Nm 3 /hr or less to heat treat the fiber bundle.

Assignees

• Mitsubishi Rayon Co

Inventors

• Oka Yusuke
• Yamamoto Nobuyuki
• Hatayama Akito

Classifications

• D01F9/32 Primary

  Apparatus therefor · CPC title

• D01F9/14

  by decomposition of organic filaments · CPC title

• F27B9/28

  for treating continuous lengths of work · CPC title

• C10B21/00 Primary

  Heating of coke ovens with combustible gases · CPC title

• F27D7/02

  Supplying steam, vapour, gases or liquids · CPC title