Abstract
	This work deals with preliminary treatment of pig iron by utilization of waste substances from metallurgical production. Theoretical analysis of the reactions of desulphurization and dephosphorization of iron melts is carried out here. Model slags with implementation of undersizes of sinter and of steelmaking slags were prepared. The experimental heats showed that pig iron could be desulphurized even by a basic oxidic slag because the high content of carbon and silicon keeps low activity of oxygen in the melt. In addition the efficient dephosphorization of the iron melt was found to be reached with low Si-content only.