Sustainable Mining and Metallurgy

In view of the problems of traditional crude tin refining technology such as long process flow, difficulty in impurity removal and heavy environmental pollution, a new process composed of “condensation and centrifugation, oxidation, continuous crystallization and vacuum volatilization” was proposed for refining of crude tin. The theoretical research on the removal of iron and arsenic by centrifugation, copper, nickel and antimony by oxidation, silver by continuous crystallization and lead and bismuth by vacuum volatilization of crude tin has been systematically carried out. The migration and distribution law of impurity components between solid-liquid and gas phases has been clarified. And small-scale, semi-industrial and industrial tests have been carried out. The experimental results show that the new green short-process refining technology of crude tin can produce 9999% refined tin, and the quality of refined tin can meet the national standard of 4N tin. Compared with the traditional crude tin refining technology, the new green short-process refining technology of crude tin has the advantages of strong adaptability of raw materials, less consumption of auxiliary materials, less discharge of “three wastes”, high direct tin yield, low slag rate sh, low comprehensive energy consumption, and low production cost.