Glass-making raw materials preparation involves thermal conversion of silica and halides, especially chlorides, or sulfates or nitrates of alkali and/or alkaline earth and/or rare earth metals using immersed burner

摘要

Preparation of compounds based on silicates of alkali metals, such as Na and K, and/or alkaline earth metals, such as Ca and Mg, and/or rare earth metals, e.g. Ce, optionally in the form of mixed silicates involves thermal conversion of silica and halides, especially chlorides, or sulfates or nitrates of the above metals, such as NaCl, KCl and CeCl4, using immersed burner(s). The combustion supporter supplied to burner(s) comprises air, oxygen-enriched air or oxygen. Fuel, e.g., natural gas or hydrogen, is supplied to the burners. The fuel can be supplied in the form of a solid containing carbon, for example charcoal or any material containing hydrocarbon polymers, optionally chlorinated. The combustion created by burner(s) assures at least partial mixing of the silica and halides, generates at least part of the water necessary for conversion, and generates halogen derivatives, notably HCl or Cl2, or H2SO4. The formed silicates are treated, namely granulated, before being supplied in the heated state to a glass furnace. Independent claim are given for: (a) apparatus for implementing the above process; (b) use of the above process or apparatus for forming vitrifiable raw materials for glass production; (c) use of the above process or apparatus for forming raw materials, especially Na2SiO3 for detergent production; (d) use of the above process or apparatus for forming raw materials, especially Na2SiO3 for precipitated silica production; (e) use of the above process or apparatus for vitrifying or rendering inert chloro-organic wastes, preferably by conversion of silica and raw material containing at least alkaline earth metals; and (f) a process for production of glass containing silica and alkali(ne earth) oxides of the type Na2O, K2O, CaO and MgO and /or rare earth oxides of the type CeO2.