An object of the present invention is to provide a method according to which a rare earth element can be efficiently recovered from a workpiece containing at least a rare earth element and an iron group element, and also wear and damage to the treatment container can be suppressed, allowing the container to be used repeatedly for a long period of time. The method of the present invention as a means for resolution is characterized in that in the heat treatment of an oxidation-treated workpiece in the presence of carbon, when the oxidation-treated workpiece is placed in a treatment container, a carbon substance is interposed between the oxidation-treated workpiece and the bottom surface of the container, and the heat treatment is performed in an inert gas atmosphere or in vacuum at a temperature of 1300 C. or more.

An object of the present invention is to provide a method according to which a rare earth element can be efficiently recovered from a workpiece containing at least a rare earth element and an iron group element, and also wear and damage to the treatment container can be suppressed, allowing the container to be used repeatedly for a long period of time. The method of the present invention as a means for resolution is characterized in that in the heat treatment of an oxidation-treated workpiece in the presence of carbon, when the oxidation-treated workpiece is placed in a treatment container, a carbon substance is interposed between the oxidation-treated workpiece and the bottom surface of the container, and the heat treatment is performed in an inert gas atmosphere or in vacuum at a temperature of 1300 C. or more.

Provided is a method for producing pellets by which, when nickel oxide ore is being pelletized and smelted to produce ferronickel, which is an iron-nickel alloy, it is possible to allow the smelting reaction to proceed effectively. A method for producing pellets according to the present invention is for producing pellets which are used in producing iron-nickel alloy and which are produced by mixing raw materials including nickel oxide ore and agglomerating the resulting mixture, wherein the method comprises: a mixing step S11 for mixing at least nickel oxide ore, a carbonaceous reducing agent, and iron oxide to generate a mixture; and a pellet formation step S12 for agglomerating the resulting mixture and forming pellets. In the mixing step S11, the mixture is generated such that the total weight of nickel and iron accounts for 30 wt % or more of the total weight of the pellets formed.

Provided is a method for producing pellets by which, when nickel oxide ore is being pelletized and smelted to produce ferronickel, which is an iron-nickel alloy, it is possible to allow the smelting reaction to proceed effectively. A method for producing pellets according to the present invention is for producing pellets which are used in producing iron-nickel alloy and which are produced by mixing raw materials including nickel oxide ore and agglomerating the resulting mixture, wherein the method comprises: a mixing step S11 for mixing at least nickel oxide ore, a carbonaceous reducing agent, and iron oxide to generate a mixture; and a pellet formation step S12 for agglomerating the resulting mixture and forming pellets. In the mixing step S11, the mixture is generated such that the total weight of nickel and iron accounts for 30 wt % or more of the total weight of the pellets formed.

Provided is a method for producing pellets by which, when nickel oxide ore is being pelletized and smelted to produce ferronickel, which is an iron-nickel alloy, it is possible to allow the smelting reaction to proceed effectively. A method for producing pellets according to the present invention is for producing pellets which are used in producing iron-nickel alloy and which are produced by mixing raw materials including nickel oxide ore and agglomerating the resulting mixture, wherein the method comprises: a mixing step S11 for mixing at least nickel oxide ore, a carbonaceous reducing agent, and iron oxide to generate a mixture; and a pellet formation step S12 for agglomerating the resulting mixture and forming pellets. In the mixing step S11, the mixture is generated such that the total weight of nickel and iron accounts for 30 wt % or more of the total weight of the pellets formed.

A method capable of efficiently producing grained iron with a low P concentration includes a first step of melting reduced iron to obtain primary molten iron, a second step of separating the primary molten iron from slag, a third step of subjecting the primary molten iron separated from the slag to dephosphorization to obtain secondary molten iron, and a fourth step of solidifying the secondary molten iron into a grained form to obtain grained iron, in which in the third step, the dephosphorization is performed by supplying an oxygen source and a CaO source to the primary molten iron, and a temperature of the secondary molten iron at the end of the dephosphorization is set to a temperature of the primary molten iron at the start of the dephosphorization or lower.

An apparatus for direct reduction of iron ore in a solid state including a pre-heating furnace for pre-heating iron ore fragments and biomass in briquettes of these materials to a temperature in the range of 400-900 C.; and a reduction assembly for briquettes from the pre-heating furnace. The reduction assembly includes a reaction chamber, a source of electromagnetic energy in the form of microwave energy, a wave guide for transferring microwave energy to the chamber for heating and reducing iron ore in briquettes from the pre-heating furnace, with biomass acting as a reductant, a source of an inert gas, pipework for supplying the inert gas to the chamber to maintain the chamber under anoxic conditions, and an outlet for discharging an offgas and any retained particulates that are generated in the chamber.