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US2536020A
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Method of making silvery iron from blackband ore
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Method of melting and refining ferrous metals
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Method of reducing iron ores
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Process for melting and refining ferrous metals
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Method for producing phosphorus
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Continuous strip furnace
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Method of calcining phosphate-bearing materials
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Process for the treatment of ores containing iron
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Electric furnace
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Method and apparatus for refining metals
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Method of recovering metals and oxides from boiler ash
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Process of making phosphoric acid and cyanamide
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Melting and refining furnace
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Electric refining furnace
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Electric furnace
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Process of making ferrosilicon
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Shaft-type electric furnace
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Annealing equipment and method
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Automatic control device
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Casting apparatus
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