| 摘要 |
PURPOSE:To efficiently perform the thermal oxidation reaction of gaseous starting material and the deposition of soot with simple constitution by putting a rodlike body in a reaction tube from the gas exhaust side end, locating one end of the body in the vicinity of a heating means, and moving the body in synchronism with the means. CONSTITUTION:A reaction tube 1 is attached to a rotating and supporting mechanism 2, and a burner 3 is moved in the longitudinal direction of the tube 1 to locally heat the wall of the tube 1. In order to reduce the hollow cross section of the tube 1, a rodlike body 22 having a suitable thickness is coaxially put in the tube 1 from the gas exhaust side end 21, and one end of the body 22 is located in the vicinity of the burner 3. The body 22 is moved in cooperation with the burner 3. The other end of the body 22 is held by a holder 24 on a moving stand 23 on which the burner 3 is mounted. The body 22 is not a nonhollow rod, and it is internally provided with a heater 25 not to stick soot to the outside peripheral surface 22 since the central part of the tube 1 is likable to be heated to a lower temp. than the tube wall. |
