Energy conservation during the smelting of ores

摘要

The invention discloses processes for preparing matched sizes of electric furnace feed materials. With the matched sizes, components of the feed mixture do not separate inside the furnace and this decreases the electric energy for smelting. Preparation of matched sizes of materials is made possible by low-temperature agglomeration followed by drying to indurate the agglomerates. Fuel requirements for induration are substantially reduced, and environmental problems associated with high-temperature agglomeration are eliminated. Phosphate ores can be agglomerated and simultaneously the ores are upgraded by increasing the P2O5 content. Unbeneficiated phosphate ores heretofore considered unsuited for smelting can be used as phosphate sources for the production of phosphorus. A combustible gas consisting mainly of carbon monoxide and hydrogen is generated when ores are smelted. Processes are disclosed for cleaning the gas to permit it to be burned in a facility for the cogeneration of electric energy. At phosphorus furnaces the potential energy in the gas is equal to about 65 percent of the electric energy used in smelting; consequently, the net electric energy consumption can be substantially reduced by operation of a cogeneration facility.