A two-stage lead smelting process. In the first stage, the lead concentrate is oxidized by injecting air down a "Sirosmelt" lance, using helical vanes to swirl the gas. In the second, the high-lead slag is reduced with coal
Comyns, Alan E. Dictionary, Encyclopedic Dictionary of Named Processes in Chemical Technology (3rd ed.), Alan E. Comyns (Ed.), Boca Raton, FL, CRC Press LLC, USA 2000, http://worldtracker.org/media/library/Science/Chem istry/Synthesis/Encyclopedic%20Dictionary%20of%20N amed%20Processes%20in%20Chemical%20Technology.pdf, (Named Chem Procss - Amer) {35}