Dense powder from beneficiated dolomites for producing tar-bonded dolomite refractories

Conclusions

Flotation-beneficiated dolomites from the Novotroitsk and Elenovsk deposits consist of high-quality (in terms of chemical composition) materials containing less than 0.65% SiO₂ and 0.4% sesquioxide. The particularly low concentration of impurity oxides is a feature of the beneficiated Elenovsk dolomite.

The apparent density of the pellet is more than 3 g/cm³ which is achieved after sintering by additional grinding of the beneficiated dolomite, pelletizing the milled product, and burning the pellets at a temperature of at least 1700°C. The beneficiated Novotroitsk dolomite is sintered better than the Elenovsk; this is due to its fine grained crystalline structure and its concentration of impurity oxides.

The beneficiated calcined dolomites from the Novotroitsk and Elenovsk deposits having an apparent density of more than 3 g/cm³ are products suitable for making high-quality tar-bonded dolomite and tarbonded dolomite-magnesite products satisfying the requirements of refractories for converters.

It would be desirable to carry out industrial experiments on the beneficiation of dolomites (producing a batch of at least 1000 tons) followed by burning the dolomite, preparation of tar-bonded dolomite refractories, and testing them in service.