Method of preparing a melt for the production of man-made mineral fibres
AssigneeRockwool A/S
InventorsLars Elmekilde Hansen, Haosheng Zhou
Life of this patent
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Abstract
The invention relates to a method of preparing a mineral melt in a cupola furnace that uses at least one plasma torch to provide heat energy to the furnace. The plasma torch uses nitrogen, carbon monoxide, carbon dioxide, or a mixture thereof as the carrier gas. The invention also relates to a cupola furnace for the preparation of the mineral melt, and the use of a plasma torch in a cupola furnace to reduce the amount of NOx and/or hydrogen in the furnace off-gas.
Claims18
A process for preparing a mineral melt in a cupola furnace, said process comprising supplying mineral material to the cupola furnace, and providing heating energy to the cupola furnace, said cupola furnace having a base, such that said mineral material is melted to form a mineral melt that collects in the base of the cupola furnace, and wherein the process produces off-gas,
- wherein:
- the cupola furnace comprises at least two temperature zones, including a hot zone at the base of the cupola furnace and an oxidation zone above the hot zone;
- (i) the cupola furnace is equipped with at least one tuyere providing a source of oxygen in the oxidation zone;
- (ii) the cupola furnace comprises at least one plasma torch that uses as carrier gas nitrogen, carbon monoxide, carbon dioxide, or a mixture thereof, and provides plasma heating in the hot zone;
- (iii) greater than 50% of the heating energy provided to the cupola furnace is provided by the at least one plasma torch;
- (iv) the temperature in the oxidation zone is below 1,400° C.;
- (v) the temperature in the hot zone is greater than the temperature in the oxidation zone;
- (vi) water is substantially excluded from any zone of the cupola furnace where the temperature is above 750° C.
Dependencies are inferred from the claim text.