Some methods for making a granular material comprise crushing demetallized slag particles with one or more crushers and screening the crushed demetallized slag particles with one or more screens to separate the demetallized slag particles into two or more fractions, the granular material comprising at least one of the fractions of the demetallized slag particles. Prior to the crushing, ones of the demetallized slag particles having a size that is less than or equal to 2 inches can account for at least 90% of the demetallized slag particles. An iron-compound content of the demetallized slag particles, by weight, can be less than or equal to 10%. Crushing and screening can be performed such that ones of the demetallized slag particles of the granular material having a size that is less than or equal to 1.25 mm account for at least 90% of the demetallized slag particles of the granular material.

A slag discharge door device for an electric furnace is provided. The device prevents slag from flowing out via a slag discharge port by making a discharge control door body move up and down to and from the upper surface of a supporting body where slag is discharged by flowing to the upper surface, and the discharge of slag is controlled, such that during steel-making work in the electric furnace, the outflow of slag is prevented and heat losses are reduced, the efficiency of arc heat due to the formation of foamed slag is increased, and valuable metals are recovered from the molten slag thereby increasing the percentage of molten steel recovered.

The present application refers to zinc recovery process from steelworks powder, and to obtain a zinc sulfate solution with 12% Zn by weight with the expected degree for fertilizer. Such an approach can aim to add value to a steelmaking waste, by partially converting environmental liability in commercial product taking advantage of the steelworks' powder as a raw material for the production of a liquid fertilizer and ready for use, containing zinc and sulfur with low liquid effluent production. Such an approach can be advantageous as to simplicity, use of mild temperatures, use of a single reactant, overall conversion of the reactants into a product solution of commercial quality, ready for use as a foliar fertilizer with low generation of wastewater and without generation of additional waste.

The present application refers to zinc recovery process from steelworks powder, and to obtain a zinc sulfate solution with 12% Zn by weight with the expected degree for fertilizer. Such an approach can aim to add value to a steelmaking waste, by partially converting environmental liability in commercial product taking advantage of the steelworks' powder as a raw material for the production of a liquid fertilizer and ready for use, containing zinc and sulfur with low liquid effluent production. Such an approach can be advantageous as to simplicity, use of mild temperatures, use of a single reactant, overall conversion of the reactants into a product solution of commercial quality, ready for use as a foliar fertilizer with low generation of wastewater and without generation of additional waste.

A molten bath-based direct smelting process comprises controlling the process conditions in a direct smelting vessel so that molten slag in a molten bath of metal and slag in the vessel has a viscosity in a range of 0.5-5 poise when the slag temperature is in the range of 1400-1550 C. in the molten bath in the vessel.

A molten bath-based direct smelting process comprises controlling the process conditions in a direct smelting vessel so that molten slag in a molten bath of metal and slag in the vessel has a viscosity in a range of 0.5-5 poise when the slag temperature is in the range of 1400-1550 C. in the molten bath in the vessel.

The method according to the invention for treating steel mill slag includes the steps of A) providing steel mill slag in solid form having a fineness such that the steel mill slag has a specific surface area according to BET of 0.1 m2/g or more; step B) treating the steel mill slag by heating it to a temperature of at least 800 Celsius, while adding oxidizing agents and auxiliary agents; and step C) separating iron (III) oxide and iron (II,III) oxide out of the treated steel mill slag.

The method according to the invention for treating steel mill slag includes the steps of A) providing steel mill slag in solid form having a fineness such that the steel mill slag has a specific surface area according to BET of 0.1 m2/g or more; step B) treating the steel mill slag by heating it to a temperature of at least 800 Celsius, while adding oxidizing agents and auxiliary agents; and step C) separating iron (III) oxide and iron (II,III) oxide out of the treated steel mill slag.

Pyro-hydrometallurgical methods are described to economically and environmentally recover a target metal from iron slag or steel slag. For instance, the method can enable subjecting an iron or steel slag feed to acid-baking with an acid to produce a dried mixture comprising at least one soluble metal salts, then subjecting the dried mixture to water leaching to an aqueous solution comprising an aqueous leachate rich in said target metal and solid residues and subsequently separating the aqueous leachate rich in said target metal from the solid residues. This acid-baking water-leaching method facilitates efficient recovery of target metal compared to conventional methods.

Provided herein is a method of treating and upgrading industrial furnace by-products, such as steelmaking slag and incinerator bottom ash (IBA) into valuable products, the method comprising the steps (a) providing the industrial furnace by-product, (b) subjecting the industrial furnace by-product to separation crushing to obtain crushed industrial furnace by-products, (c) subjecting the crushed industrial furnace by-products to one or more magnetic separation step(s) to separate magnetic and non-magnetic particles, and (d) optionally subjecting said non-magnetic particles to fine grinding to obtain fine grinded particles. The fine grinded particles can then be used to produce cement clinkers in kiln.