Some variations provide a composition for reducing a metal ore, the composition comprising a carbon-metal ore particulate, wherein the carbon-metal ore particulate comprises at least about 0.1 wt % to at most about 50 wt % fixed carbon on a moisture-free and ash-free basis, and wherein the carbon is at least 50% renewable carbon as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Some variations provide a process for reducing a metal ore, comprising: providing a biomass feedstock; pyrolyzing the feedstock to generate a biogenic reagent comprising carbon and a pyrolysis off-gas comprising hydrogen or carbon monoxide; obtaining a metal ore comprising a metal oxide; combining the carbon with the metal ore, to generate a carbon-metal ore particulate; optionally pelletizing the carbon-metal ore particulate; and utilizing the pyrolysis off-gas to chemically reduce the metal oxide to elemental metal, such as iron. The disclosed technologies are environmentally superior to conventional processes based on coal.

Some variations provide a composition for reducing a metal ore, the composition comprising a carbon-metal ore particulate, wherein the carbon-metal ore particulate comprises at least about 0.1 wt % to at most about 50 wt % fixed carbon on a moisture-free and ash-free basis, and wherein the carbon is at least 50% renewable carbon as determined from a measurement of the .sup.14C/.sup.12C isotopic ratio. Some variations provide a process for reducing a metal ore, comprising: providing a biomass feedstock; pyrolyzing the feedstock to generate a biogenic reagent comprising carbon and a pyrolysis off-gas comprising hydrogen or carbon monoxide; obtaining a metal ore comprising a metal oxide; combining the carbon with the metal ore, to generate a carbon-metal ore particulate; optionally pelletizing the carbon-metal ore particulate; and utilizing the pyrolysis off-gas to chemically reduce the metal oxide to elemental metal, such as iron. The disclosed technologies are environmentally superior to conventional processes based on coal.

A method for controlling pellet quality in iron ore production includes the steps of mixing water, binder and iron ore particles in at least one mixer to form a mixture (step (i)) and pelletizing the mixture into green pellets (step (ii)). Between step (i) and step (ii), a part of the mixture is taken in a sampling operation, formed into a test specimen and subjected to a test.

The present invention relates to the use of hydrophobically associative copolymers as binders for pelletizing metal containing ores such as iron containing ores. The copolymers comprise monomer units derived from at least one hydrophobically as sociative monomer, preferably at least one unsaturated hydrophobically associating monomer.

A hot briquetted iron (HBI) production apparatus including a feeder unit, a quantitative dispenser unit, a hot briquette forming unit, and a cylindrical cooler, the feeder unit cooling and transporting direct reduced iron (DRI), the quantitative dispenser unit pulverizing the DRI and discharging a fixed amount of the DRI each time, the hot briquette forming unit forming hot iron briquettes by hot-pressing the DRI, the cooler unit cooling the hot iron briquettes, and including a cylindrical body with an inlet and an outlet, a transport screw or blade for transporting the hot iron briquettes, and a cooling water spray nozzle, the transport screw and the cooling water spray nozzle being disposed inside the cylindrical body, the hot iron briquettes being introduced into the cooler unit through the inlet and discharged from the cooler unit through the outlet, and cooling water being discharged from the cooler unit through the inlet.

The present patent document refers to the products and processes of Ceramic Proppant production from iron ore and/or sterile from its exploitation and/or tailings from its beneficiation, and/or fine and ultra-fine particles from other sources with similar properties, by agglomeration of these materials, and subsequent heat treatment, resulting from the combination of different technologies, previously used for other purposes, capable of obtaining a ceramic material, transforming the materials, including waste and sterile from other processes, into high value products, and reducing the impact of mining activity, with the best use of mineral resources.

In the future, this practice may allow for the reduction of waste and tailings disposal in new dams and piles, as well as the resumption of structures such as piles and old dams.

A direct reduction process for the production of ferrochrome from chromite ore or concentrate is disclosed. According to the present invention, calcium chloride (CaCl.sub.2) is added as a catalyst to accelerate the solid reduction and enhance the particle growth of the metallic phase (i.e. ferrochrome) during reduction. The reduction of chromite ore or concentrate takes place at much lower temperatures (e.g. 1200 to 1400° C.) compared to the conventional smelting technologies, and the ferrochrome particles formed are segregated from the unwanted residual gangue and spinel particles, facilitating their subsequent physical separation.

In one aspect, the disclosure relates to a microwave-assisted comminution method for achieving more efficient beneficiation and later hydrometallurgical recovery of rare earth elements and other metals from coal fly ash particles. The method requires only a short processing time, is energy efficient, allows for better process control, and is environmentally advantageous compared to current methods. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

Some variations provide a carbon-negative carbon product that is characterized by a carbon intensity less than 0 kg CO.sub.2e per metric ton of the carbon-negative carbon product, wherein the carbon-negative carbon product contains at least about 50 wt % carbon. In some embodiments, the carbon intensity is less than 500 kg CO.sub.2e per metric ton of the carbon-negative carbon product. Other variations provide a carbon-negative metal product (e.g., a steel product) that is characterized by a carbon intensity less than 0 kg CO.sub.2e per metric ton of the carbon-negative metal product, wherein the metal product contains from 50 wt % to 100 wt % of one or more metals and optionally one or more alloying elements. In some embodiments, the carbon-negative metal product is characterized by a carbon intensity less than 200 kg CO.sub.2e per metric ton of the carbon-negative metal product. The carbon-negative metal product can contain a wide variety of metals.

The present invention relates to an ironmaking feedstock comprising a solid CaFe.sub.3O.sub.5 phase. The ironmaking feedstock may be produced by a process comprising reacting a combination of a calcium source and magnetite at elevated temperature under reducing conditions sufficient to produce the solid CaFe.sub.3O.sub.5 phase. The product may be in the form of agglomerates such as pellets, with a compressive strength such that the product is suitable for transportation.