| 摘要 |
PCT No. PCT/DK89/00309 Sec. 371 Date Jun. 21, 1991 Sec. 102(e) Date Jun. 21, 1991 PCT Filed Dec. 22, 1989 PCT Pub. No. WO90/07470 PCT Pub. Date Jul. 12, 1990.A method of preparing a melt for mineral fibre production wherein a mixture of mineral fibre-forming raw materials is introduced into a shaft furnace and is heated to melting temperature by a plasma gas stream formed in a plasma torch and wherein waste material from mineral fibre production is introduced into the plasma gas stream by a rotatable screw conveyor mounted in a feed pipe, the melt formed in the shaft furnace is being discharged from the bottom of the furnace and passed to a fiberizing apparatus in which it is converted into mineral fibres. |
