Patent ID: 7371342

Claim:
A system for keeping blow nozzles free of accreted obstruction wherein the flow nozzles extend through casings of reactors or fusion converters used in processing mined materials or used in practicing in pyrometallurgy, the system comprising: at least one blow nozzle having a central axis, an outlet end adjacent to an inner wall of a casing for a metallurgical processing vessel and opening beneath the surface of a melting bath in the vessel, the blow nozzle having an enriched air inlet for connection to a source of enriched air that flows under a pressure at least as high as atmospheric pressure into the melting bath, the inlet for the source of enriched air being above the nozzle; a tube fluidly connected to the nozzle outlet upstream of the outlet end of the nozzle and downstream of the enriched air inlet of the nozzle, the tube being below the nozzle; an air accumulator that stores compressed air at a pressure substantially above the pressure of the enriched air; a valve between the accumulator and the tube, the valve being a rapidly opening valve that introduces compressed air impulses into the nozzle of a duration and pressure sufficient to avoid formation of obstructing accretions at the outlet end of the nozzle, which accretions interfere with air flow through the nozzle, and a directed accretion created by the compressed air impulses, the directed accretion being in the form of a tubular extension of the nozzle outlet and extending axially out into the melt bath.