METHOD AND APPARATUS FOR RECOVERING PRECIOUS METALS FROM INTERMEDIATE PRODUCTS Russian patent published in 1998 - IPC

FIELD: pyrometallurgy. SUBSTANCE: method is characterized by that lower part of reaction space of furnace is first formed from refractory sodium silicate by way of loading sodium carbonate together with quartz sand or crushed glass which are melted at 1150- 1250 C, after which upper part of reaction space is formed by loading and melting (at 1000-1100 C) sodium carbonate followed by loading charge materials into fusion preliminarily produced. Charge is hold until completion of reaction of slagging foreign metals and sedimentation of precious metals into layer of tough refractory slag, after which upper fusible slag is decanted and loading of charge materials and decantation of upper fusible slag operations are then many times repeated. After last portion of fusible slag has been decanted, lower refractory slag and precious metal alloy are melted to free-running state, decanted, and alloy is separated from slag. equipment for implementation of the method is distinguished by having supplementary outlet hole located at the level of cylinder to cone transition. EFFECT: enabled processing intermediate product with low content of precious metals. 2 cl, 1 dwg, 2 ex