Dependence of the properties of dinas on the technological parameters and the firing atmosphere

Conclusions

We confirmed that it is promising to use quartzite bodies containing quartzite grains having a maximum size of 2 mm for producing dinas from the Ovruchsk as well as the Pervoural'sk quartzites with decreased density and additional growth and a low content of residual quartz.

In order to ensure low density, additional growth, and residual quartz content and a high degree of tridymitization of the dinas products obtained from the Pervoural'sk and the Ovruchsk quartzites, the temperature in the firing zone of the tunnel furnaces must be in the 1410–1420°C and 1420–1440°C ranges, respectively.

We did not find specific advantage of any of the three types of iron-bearing mineralizers used in this study (roasted pyrite residue, converter slime, and scale). Similarly, using the reducing atmosphere for firing did not have a positive effect on the properties, on the reduction of the content of residual quartz, and on the increase of the quantity of tridymite.