| 摘要 |
PURPOSE:To produce high-purity silica beads having a particular particles size distribution, at a low cost, by hydrolyzing a silicon halide in flame in a vapor phase, dispersing and melting the produced high-purity ultrafine silica powder in a burner immediately after production, and quenching in a gas stream. CONSTITUTION:A high-purity ultrafine silica powder having a particle diameter of about 0.01mum is produced by the vapor-phase flame hydrolysis of a silicon halide. The ultrafine powder is collected by the hopper 1 immediately after the production, and is transferred by the screw feeder 2 quantitatively and dispersed in an oxygen gas stream introduced through the pipe 10. The oxygen gas is supplied through the pipe 11 to the intermediate tube 15 of a triple-tube burner. The hydrogen gas supplied through the core tube 13 and the outer tube 14 is burnt with the oxygen gas in the combustion chamber 4, and the ultrafine silica is melted in the flame. The molten silica is quenched with secondary air supplied from the inlet 16. The high-purity silica beads having particles diameter of 0- 250mum are recovered by the cyclone 5 and the bag filter 6 and collected in the bunkers 8, 9, and the separated air and steam are exhausted to the atmosphere by the blower 7.
|
