ES337898A1 - High efficiency plasma processing head including a diffuser having an expanding diameter - Google Patents

Abstract

Plasma processing apparatus includes coaxial hollow anode and cathode elements 10, 11, with passages 12, 13 for passing a flow of gas therethrough and for reception of an arc discharge pattern penetrating the electrodes in the path of the flow. A gas ring 16 provides inlet ports (17), (Fig. 3, not shown), to receive gas from a duct 22 via a plenum (22a) to direct the inlet flow in a spiral or vortex within a plenum 18 between the electrode terminal flanges 19 and 20. The vortex flow divides at locus 21 and enters throat regions 12a and 13a of passages 12 and 13. Coolant fluid enters passages 32, 34, via ducts 38, 39, circulates round passages 33, 35, and exits via ducts 40, 41. There is produced a gas unstabilized arc at points of variable arc attachment to the electrodes (see Fig. 2, not shown), due to the vortex or rotating character of the gas flow. Downstream valves 71-73 are adjustable to provide turbulent flow conditions or magnetic field producing coils (120) or (128), (129), are energizable to rotate the points of arc attachment (Figs. 7, 8, not shown). Quench fluid is introduced into the path of the hot gas flowing downstream of the points of arc attachment via bodies 48, 49, forming plenum chambers 54, 55, to which quench fluid is supplied via ducts 56, 57. The fluid then passes via ports 58, 59 into the gas at regions 60, 61, and sharply reduces the gas temperature to aid in terminating chemical reactions occurring therein. Natural gas may be fed in to produce acetylene, or particulate material such as iron ore may be injected via ducting (80), (Fig. 3, not shown), at a point downstream of the flow division locus 21, to produce a product of desired metallurgical properties.