Patent classifications
C22B23/023
Method for smelting nickel oxide ore
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.
Method for producing pellets and method for producing iron-nickel alloy
Provided is a production method for producing pellets that are used for producing an iron-nickel alloy and that are produced by mixing at least a nickel oxide ore, a carbonaceous reducing agent, and an iron oxide and agglomerating the obtained mixtures, the method comprising: a step S11 for producing at least two types of mixtures having different mixing ratios of nickel oxide ore, carbonaceous reducing agent, and iron oxide; and a step S12 for forming pellets, which are agglomerates having a layered structure, by using the two or more types of mixtures such that the mixture with the highest content ratio of iron oxide, among the two or more types of mixtures forms the outermost layer.
METHOD FOR SMELTING SAPROLITE ORE
Provided is a smelting method whereby a reaction for reducing pellets, said pellet being formed by using a saprolite ore as a starting material, can be effectively conducted and thus an iron/nickel alloy having a nickel grade of, for example, 16% or greater can be obtained. The method comprises: a pellet production step (S1) for producing the pellets from the saprolite ore; and a reduction step (S2) for heating and reducing the obtained pellets in a smelting furnace. In the pellet production step (S1), at least the saprolite ore and a preset amount of a carbonaceous reducing agent are mixed together to produce the pellets. In the reduction step (S2), a hearth carbonaceous reducing agent is preliminarily spread on the hearth of the smelting furnace and the pellets produced above are placed on the hearth carbonaceous reducing agent and then subjected to a heat reduction treatment.
Method for smelting nickel oxide ore and method for charging pellets
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.
METHOD FOR SMELTING NICKEL OXIDE ORE
A method for smelting nickel oxide ore according to the present invention uses pellets of nickel oxide ore and is characterized by comprising: a pellet production step S1 for producing pellets from nickel oxide ore; a reduction step S2 for heating the resulting pellets at a predetermined reduction temperature in a reduction furnace to obtain a mixture of iron-nickel alloy and slag; and a separation step S3 for separating out and recovering the iron-nickel alloy form the resulting mixture, the separation step S3 comprising the creation of pulverized matter by pulverizing the mixture so that at least the slag becomes smaller than 2 mm, and sorting the resulting pulverized matter with a magnetic force of 300 to 600 gauss.
METHOD FOR SMELTING NICKEL OXIDE ORE AND METHOD FOR CHARGING PELLETS
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.
METHOD FOR PRODUCING PELLETS AND METHOD FOR PRODUCING IRON-NICKEL ALLOY
Provided is a production method for producing pellets that are used for producing an iron-nickel alloy and that are produced by mixing at least a nickel oxide ore, a carbonaceous reducing agent, and an iron oxide and agglomerating the obtained mixtures, the method comprising: a step S11 for producing at least two types of mixtures having different mixing ratios of said nickel oxide ore, said carbonaceous reducing agent, and said iron oxide; and a step S12 for forming pellets, which are agglomerates having a layered structure, by using said two or more types of mixtures such that the mixture with the highest content ratio of said iron oxide, among said two or more types of mixtures that have been obtained, forms the outermost layer.
Method for producing ferroalloy containing nickel
The invention relates to a method for producing a ferroalloy containing nickel. From a fine-grained raw material containing iron and chromium and a fine-grained raw material containing nickel, a mixture is formed with binding agent, the mixture is agglomerated so that first formed objects of desired size are obtained. The objects formed are heat treated in order to strengthen the objects so that the heat treated objects withstand conveyance and loading into a smelter furnace. Further, the objects are smelted under reducing circumstances in order to achieve ferrochromenickel, a ferroalloy of a desired composition containing at least iron, chromium and nickel.