Filter dust smelting with reduced electrode erosion - in which electrodes are inserted into glass from above into mixt. of dust and additives

摘要

To melt filter dust, in smelting furnace fitted with glass troughs, the dust is mixed with other materials, e.g. lime, quartz sand or flue ash to be melted by electrodes in the melting bath to give a glassy material when cool. The electrodes, using AC and pref. at mains frequency are inserted into the bath from above and pref. vertically, to heat the material through direct current passage. The depth of the electrode insertion is adjustable according to the bath level and deg. of electrode wear. The bath can be cooled, pref. by water, at a level below the surface. The zone over the bath is shrouded against the ambient atmosphere by a lid-type cover. Perf. three electrodes are used, inserted into the molten bath with a small penetration depth. The parameters to control the electrode penetration depth are the electrode voltages, the electrode currents or a combination of voltage and current. ADVANTAGE - The method reduces the problems of material in glass bath furnaces, reduces the strong electrode erosion and dust development, and also cuts heat loss. The additives can also be mixed at a higher speed