A method for modifying steel slag and recovering valuable elements

Abstract

The application discloses a steel slag modification and valuable element recovery method, and relates to the field of recycling of metallurgical industrial waste slag. The steel slag modification and valuable element recovery method comprises the following steps: step 1, after tapping of an initial smelting furnace is completed, a modification agent is added in the bottom of a modification reduction furnace or with liquid slag flow during high-temperature steel slag tapping; step 2, hot molten slag after modification in step 1 is poured into the modification reduction furnace, fuel gas is sprayed at the mouth of the modification reduction furnace to heat the molten slag to 1450 DEG C-1650 DEG C, and the molten slag in the molten pool is stirred; step 3, a reducing agent is sprayed on the modified molten slag at the mouth of the modification reduction furnace; and step 4, after reduction is completed, the molten slag pool is solidified to realize layering of the molten slag and metallic iron liquid. The method provided by the application utilizes the residual heat of the steel slag during tapping to perform molten modification and carbon thermal reduction treatment on the steel slag, and spraying of the fuel gas and the reducing agent ensures that the valuable elements in the slag are reduced as much as possible.

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