Calumite – an essential raw material for the glass industry
Calumite is a glassy calcium-alumino-silicate, produced from granulated blast furnace slag. Its unique melting and refining properties enable glassmakers to reduce energy consumption and reduce CO2 and NOx emissions while improving glass quality.
Calumite is a granular material that is 99% glassy in nature. It has traditionally been viewed as an alumina source but it is a valuable source of all the major glass making oxides. The particle size distribution ensures it is compatible with other glass making raw materials.
Table 1 typical Calumite chemical composition
| Oxide | % |
|---|---|
| CaO | 38 – 44 |
| SiO2 | 36 – 40 |
| Al2O3 | 6 – 14 |
| MgO | 7 – 10 |
| S2 – | 0.7 – 0.9 |
| Fe2O3 | 0.15 – 0.3 |