Producing solar silicon useful in solar industry, comprises subjecting saw-waste to hydrometallurgical extractive enrichment process, compacting silicon-concentrate, subjecting to pyrometallurgical refining and converting into solar silicon

摘要

Producing solar silicon from silicon (5-40 wt.%) containing mineral oil- or glycol-based saw-waste dispersion, which is obtained from the production of wafers, comprises (i) subjecting the obtained saw-waste to a hydrometallurgical extractive enrichment process under standard conditions, (ii) compacting the silicon-concentrate containing 75-95 wt.% of silicon, obtained in the step (i), and subjecting to a pyrometallurgical refining at 1400-1600[deg] C, and (iii) converting the obtained silicon with a purity of 95-99.5 wt.% into crystalline solar silicon, in a conventional manner.