Induction plasma burner with supply pipe for introducing powder into plasma chamber incorporates hollow square-section coil with high-frequency feed surrounding wall of cylindrical plasma chamber

摘要

The wall (14) of the plasma chamber (12) may be made of alumina or quartz. Hydrogen or argon may be passed through the hollow induction coil (18). High-frequency alternating current is fed to the coil from a generator (60). The coil induces a high-frequency electromagnetic field in the plasma chamber to heat and maintain the plasma. There is an annular channel (70) for cooling air which flows past the induction coil (18). The hydrogen or argon may be used as a working gas and may be admitted to the plasma chamber through an inlet pipe (26,29) with a side branch (30) admitting powdered material. A plasma generator (34) ignites the plasma in the plasma chamber. It has an annular chamber (40) and a narrow air gap (50) and surrounds the gas and powder inlet.