Foundry dust from blasting and grinding of castings contain a high amount of iron, ergo it is possible its recycling in foundry process. Dust was compacted by briquetting, two kinds of briquettes were prepared (A contained 95% magnetic part of dust from casting blasting +5% bentonite and B contained 95% mixture of dust from casting grinding and magnetic part of dust from casting blasting + 5% bentonite) and used as a part of charge into the electric induction furnace. It was found that addition of briquettes has had an influence of a chemical composition of cast iron above all on content of sulphur, phosphorus and silicon. It was not reflected in decrease in tensile strength and in microstructure. Yield of metal from briquettes was not lower then 70%.
The article describes the trend towards increased use of induction crucible furnaces for cast iron smelting. The use of gas cupola’s duplex process – induction crucible furnace – has been proved the effective direction of scientific and technical advance in the foundry industry. Gas cupolas and induction furnaces are used for cast iron smelting at the Penza Compressor Plant where in the 1960s the author developed and introduced gas cupolas for the first time in the world. In the article, the author represents the findings of the investigation on thermodynamics of crucible reduction of silicon, which is pivotal when choosing the technological mode for cast iron smelting in induction furnaces. The author proposes a new reaction crucible diagram with due account of both partial pressure and activity of the components involved into the process. For the first time ever, the electrochemical mechanism of a crucible reaction has been studied and the correctness of the proposed diagram has been confirmed.