RECOVERY OF HELIUM FOR MANUFACTURING OPTICAL FIBER

摘要

PROBLEM TO BE SOLVED: To provide a recovering method of helium which economically recovers substantial part of helium abandoned up heretofore a manufacturing process of an optical fiber. SOLUTION: Contaminated helium flow is recovered not only from an optical fiber line-drawing stage 40 but also from a preform sintering stage 30 and/or a preform accumulation stage 20 in the manufacturing process. Recovered helium is purified to a lover grade purity for supplying to a line-drawing station or is purified to a higher purity level for supplying to all stages in the manufacturing process. Otherwise, sufficient amount of the recovered helium for supplying to the fiber line-drawing stage in the line-drawing station is purified to the lower grade purity and is recycled to the line-drawing station and residual part of the recovered helium is purified to the higher purity level and is supplied back to other stages in the process to recycle.