Method and device for melting and refining materials capable of being vitrified

Process according to one of the preceding claims, characterized in that the melting of the vitrifiable materials takes place in at least one melting chamber (2) which is equipped with burners (5) passing through its side walls and/or passing through the siege (4) and/or suspended from the roof (3) or from superstructures so that their combustion regions (6) or combustion gases develop in the mass of vitrifiable materials (7) being melted.

Process according to one of the preceding claims, characterized in that the combustion regions (6) created by the combustion of fossil fuel with the oxidizer gas(es) and/or the gases resulting from the said combustion convectively stir the vitrifiable materials (7).

Process according to one of the preceding claims, characterized in that the melting is preceded by a step of preheating the vitrifiable materials to at most 900° C.

Process according to one of the preceding claims, characterized in that the vitrifiable materials comprise batch materials and/or cullet and/or vitrifiable scrap and/or combustible elements, especially glass-plastic composites, glass-metal composites, organic materials, or coal.

Process according to one of the preceding claims, characterized in that the refining operation is carried out on the molten vitrifiable materials of the glass type in the foamy state, having especially a density of approximately 0.5 to 2 g/cm3.

Process according to one of the preceding claims, characterized in that the vitrifiable materials contain refining promoters, especially reducing additives of the coke type, preferably having an average particle size of less than 200 μm, sulphates, or fluorine- or chlorine-based additives, or nitrates of the NaNO3 type.

Process according to one of the preceding claims, characterized in that the melting is carried out at 1400° C. at most, especially 1380 or 1350° C. at most, and the refining at 1500° C. at most.

Process according to one of the preceding claims, characterized in that the refining is carried out in at least one static compartment lying downstream of the melting chamber (2), of the flow-canal type (9), and provided with one or more means for forcing the molten vitrifiable materials to be refined in a thin layer, especially to a depth of at most 15 cm, preferably to at most 10 cm, with flow of the plug-flow type.

Process according to one of the preceding claims, characterized in that all or some of the vitrifiable materials are introduced into the melting chamber (2) below the level of the mass of vitrifiable materials being melted.

Apparatus for melting and refining vitrifiable materials, especially intended for implementing the process according to one of the preceding claims, characterized in that it comprises:

• at least one melting chamber (2) equipped with burners (5) which are fed with fossil fuel(s) of the natural gas type and with oxidizer(s) of the air or oxygen type, the said burners being placed so as to inject the said fuels/gases or gases resulting from their combustion below the level of the mass (7) of vitrifiable materials introduced into the said melting chamber;
• means for refining the molten vitrifiable materials in the form of a “thin layer”, in the actual melting chamber (2) or in at least one refining compartment (9, 21) downstream of the said chamber.