Provided is a method by which it is possible to collect valuable metals from raw material including waste lithium-ion batteries or the like. The present invention is a method which includes: a step for preparing raw material including at least Li, Al, and the valuable metals; a step for obtaining a reduction that includes slag and an alloy containing the valuable metals by subjecting the raw material to a reduction melting treatment; and a slag separation step for collecting the alloy by separating out the slag from the reduction, wherein, in a step for adding a flux containing calcium (Ca) to the raw material and performing reduction and melting thereof, the reduction melting treatment is performed such that the liquidus line temperature of ternary Al.sub.2O.sub.3Li.sub.2OCaO slag in a phase diagram is greater than the liquidus line temperature of a ternary CuNiCo alloy in a phase diagram.

Provided is a smelting method capable of effectively promoting a reduction reaction on pellets formed using nickel oxide ore as starting material to obtain a ferronickel alloy with a high nickel grade of at least 4%. The present invention is a method for smelting nickel oxide ore wherein ferronickel alloy with a nickel grade of at least 4%, the method comprising a pellet-producing step S1 for producing pellets from nickel oxide ore, and a reducing step S2 for reduction-heating of the obtained pellets in a smelting furnace. In the pellet-producing step S1, the pellets are produced by mixing nickel oxide ore with a specified amount of a carbonaceous reducing agent as starting materials. In the reducing step S2, the produced pellets are charged in a smelting furnace in which a carbonaceous reducing agent (furnace bottom carbonaceous reducing agent) has been spread over the entire furnace bottom and reduction-heating is performed.

A single-heating stage method for reclaiming or recovering metals like nickel and vanadium from a petroleum waste byproduct has three steps: melting the petroleum waste byproduct in a reducing atmosphere, generating agglomerated metal in the melted byproduct, and lifting the agglomerated metal to an exposed surface of the melted byproduct. The metal precipitates out of the molten byproduct, agglomerates into a separate portion, and rises to an exposed surface of the melted petroleum waste byproduct even though the metal may have greater density than the molten petroleum waste byproduct. The original petroleum waste byproduct stratifies into a byproduct remnant and the agglomerated metal disk. The agglomerated metal disk is separable from the byproduct remnant and may be additionally separated into constituent metals in those embodiments with multiple metals in the disk.

Provided is a method for smelting nickel oxide ore by which the occurrence of cracking due to heat shock can be suppressed when nickel oxide ore is pelletized and charged into a smelting step (reduction step). A method for smelting nickel oxide ore according to the present invention uses pellets of nickel oxide ore, the method being characterized by comprising a pellet production step S1 for producing pellets from nickel oxide ore, and a reduction step S2 for heating the resulting pellets at a predetermined reduction temperature in a reduction furnace, the reduction step S2 comprising preheating the pellets obtained in the pellet production step S1 to a temperature of 350 to 600 C. in the reduction furnace and thereafter charging the pellets into the reduction furnace and raising the temperature of the reduction furnace to the reduction temperature.

A method for recovering a valuable element, by which method metal with a high proportion of a valuable element can be obtained. The method includes adding a reductant to an oxide containing at least one element selected from the group consisting of nickel and cobalt, followed by heating, to thereby reduce the oxide, the reductant contains at least one selected from the group consisting of metallic iron and an iron oxide, and an addition amount of the reductant is 1.3 equivalent or less.

As described herein, nickel treated with sulfur provides a surprisingly effective source of nickel atoms for generating nickel-phosphorus-containing ligand complexes useful as hydrocyanation catalysts.

The present invention provides a method for treating at least one lithium ion battery enclosed in a housing containing aluminum, comprising heating the lithium ion battery using a combustion furnace in which a combustion object is incinerated by flames, while preventing the flames from being directly applied to the housing of the lithium ion battery.

A plant for recovering metals and/or metal oxides from industrial process waste, in particular oil product refining waste, comprises a furnace; a feed line connected to a main inlet of the furnace and configured to feed the furnace with a solid waste containing metals, in particular in oxide form; an outlet line, connected to a solid phase outlet of the furnace and configured to draw a metal-enriched solid phase out of the furnace; the furnace is a belt conveyor furnace having a belt conveyor closed in a loop with a substantially horizontal configuration and having a top face, which receives the waste to treat and conveys it between two longitudinal opposite ends of the belt conveyor furnace respectively provided with the main inlet and the solid phase outlet.

A reduced metal powder prepared by processing a waste lithium ion secondary battery to recover valuable metals from the waste lithium ion secondary battery in an economical and environmentally friendly manner is described. To achieve the goal described above, the reduced metal powder according to an embodiment is prepared by pyrolyzing a waste lithium ion secondary battery, and contains metals Ni and Co and has magnetism.

A method for smelting a nickel oxide ore, wherein the reduction step progresses effectively while maintaining the strength of the pellets, comprises: a pellet production step S1 for producing pellets from a nickel oxide ore; and a reduction step S2 for reducing and heating the obtained pellets in a smelting furnace at a predetermined reduction temperature. In the pellet production step S1, a mixture is formed by mixing materials including said nickel oxide ore without mixing a carbonaceous reducing agent, and the pellets are formed by agglomerating said mixture. In the reduction step S2, in charging the obtained pellets into the smelting furnace, a carbonaceous reducing agent is spread in advance over the furnace floor of the smelting furnace and the pellets are placed on the carbonaceous reducing agent, and the pellets are reduced and heated in a state where the pellets are covered by the carbonaceous reducing agent.