Abstract: The invention relates to a process for manufacturing a flat ribbon of precursor glass for a glass-ceramic, comprising the continuous floating of the molten glass on a bath of molten metal in a float chamber, said glass being poured in the molten state at a temperature above its devitrification onset temperature onto the molten metal upstream of the chamber, said glass progressively forming a ribbon that runs along said metal bath, the cooling rate of the glass being at least 18° C./min between, on the one hand, the moment when the glass is at the theoretical temperature for which the devitrification rate is a maximum and, on the other hand, the later moment when the glass is at the theoretical temperature at which the devitrification crystal growth rate becomes less than 1 micron per minute. The glass thus floated does not undergo any devitrification.

Abstract: The invention relates to a furnace for the continuous melting of a composition comprising silica, the said furnace comprising at least two tanks in series, said tanks each comprising at least one burner submerged in the melt. The invention also relates to the process for manufacturing compositions comprising silica using the furnace, the silica and the fluxing agent for the silica being introduced into the first tank. The invention makes it possible to produce glass color frits, tile frits and enamel with a high productivity, low temperatures and short transition times.

Abstract: The invention relates to a process for manufacturing a flat ribbon of precursor glass for a glass-ceramic, comprising the continuous floating of the molten glass on a bath of molten metal in a float chamber, said glass being poured in the molten state at a temperature above its devitrification onset temperature onto the molten metal upstream of the chamber, said glass progressively forming a ribbon that runs along said metal bath, the cooling rate of the glass being at least 18° C./min between, on the one hand, the moment when the glass is at the theoretical temperature for which the devitrification rate is a maximum and, on the other hand, the later moment when the glass is at the theoretical temperature at which the devitrification crystal growth rate becomes less than 1 micron per minute. The glass thus floated does not undergo any devitrification.

Abstract: The invention relates to a process for manufacturing a glass by melting, at more than 1300° C., batch materials comprising silica and an alkali or alkaline-earth metal sulfate, characterized in that a sulfide is added to the batch materials in order to reduce the height of foam at the surface of the bath of liquid glass at more than 1300° C. The invention reduces the formation of foam at the surface of the glass and improves the heat exchanges between the overhead burners and the glass bath. The invention is particularly suitable for glass intended to be fiberized.

Abstract: The invention relates to a process for preparing a silicate of an element chosen from alkali metals, alkaline-earth metals or rare earths, comprising a reaction between silica and a sulfate of said element in a reactor equipped with at least one submerged burner within a molten mass, said submerged burner being fed with a gas containing oxygen, an excess of fuel/reducing agent being introduced into the reactor relative to the oxygen effectively consumed. The process allows the reaction to be carried out satisfactorily and at relatively low temperature.

Abstract: The invention relates to a furnace for continuously melting a silica-containing compound comprising at least two series-arranged baths each of which is provided with at least one burner submerged into molten material. Said invention also relates to a method for producing silica-containing compounds, the silica and the melt thereof being loaded into the first bath. The invention is intentionally adapted for the high performance production of frits for re-enameling ceramic products (sandstone, faience and burnt clay) at low temperatures and a fast transition time.

Abstract: The invention relates to a method for treating wastes, in particular from the production of mineral fibres such as fibreglass wool or rock fibres associated with organic binders and optionally with water or other metal and/or organic matters consisting in fusing a waste mass (9) by supplying a pure oxygen or an oxygen-enriched air in order to obtain a mineral material usable in the form of a vitreous raw material for glass melting and in inputting energy by means of at least one burner submerged under the waste mass (9). A device for carrying out said method is also disclosed.

Abstract: The subject of the invention is a device for melting batch materials that combines at least two separate melting modules, including a module A(1) which is predominantly fitted with heating means in the form of crown burners and/or submerged electrodes, and a module B(2) which is predominantly fitted with heating means in the form of submerged burners.

Abstract: The invention relates to a process for preparing a silicate of an element chosen from alkali metals, alkaline-earth metals or rare earths, comprising a reaction between silica and a sulfate of said element in a reactor equipped with at least one submerged burner within a molten mass, said submerged burner being fed with a gas containing oxygen, an excess of fuel/reducing agent being introduced into the reactor relative to the oxygen effectively consumed. The process allows the reaction to be carried out satisfactorily and at relatively low temperature.

Abstract: The invention relates to a furnace for the continuous melting of a composition comprising silica, the said furnace comprising at least two tanks in series, said tanks each comprising at least one burner submerged in the melt. The invention also relates to the process for manufacturing compositions comprising silica using the furnace, the silica and the fluxing agent for the silica being introduced into the first tank. The invention makes it possible to produce glass color frits, tile frits and enamel with a high productivity, low temperatures and short transition times.

Abstract: The subject of the invention is a device for melting batch materials that combines at least two separate melting modules, including a module A(1) which is predominantly fitted with heating means in the form of crown burners and/or submerged electrodes, and a module B(2) which is predominantly fitted with heating means in the form of submerged burners.