摘要:
A method for manufacturing molten iron includes a step of charging a carbonaceous material, a flux, and solid reduced iron obtained by thermally reducing carbon composite iron oxide agglomerates into an arc melting furnace and melting the solid reduced iron using arc heating in the melting furnace while an inert gas is blown into a molten iron layer contained in the melting furnace from a bottom blowing tuyere disposed on a bottom of the melting furnace to stir the molten iron layer, wherein the carbonaceous material is charged so that a carbonaceous material suspending slag layer in which the carbonaceous material is suspended is formed in an upper portion of a slag layer formed on the molten iron layer by slag produced when the solid reduced iron is melted into the molten iron and so that a carbonaceous material coating layer composed of only the carbonaceous material is further formed on the carbonaceous material suspending slag layer, and the molten iron and the slag stored in the melting furnace are tapped from a tap hole formed in a lower portion of a furnace wall of the melting furnace.
摘要:
A method for manufacturing molten iron comprises charging a carbonaceous material, a flux, and solid reduced iron obtained by thermally reducing carbon composite iron oxide agglomerates into an arc melting furnace and melting the solid reduced iron using arc heating in the melting furnace while an inert gas is blown into a molten iron layer from a bottom blowing tuyere on a bottom of the melting furnace, wherein: a carbonaceous material suspending slag layer is formed in an upper portion of a slag layer formed on the molten iron layer when the solid reduced iron is melted into the molten iron; a carbonaceous material coating layer having the carbonaceous material is formed on the carbonaceous material suspending slag layer; and the molten iron and the slag stored in the melting furnace are tapped from a tap hole formed in a lower portion of a furnace wall of the melting furnace.
摘要:
A process for producing molten iron is a process in which while an inert gas is blown into a molten iron layer in an iron bath type melting furnace through bottom-blown tuyeres provided in a hearth bottom thereof to stir the molten iron layer, a carbon material, an additive flux, and solid reduced iron obtained by heating reduction of carbon composite iron oxide briquettes are charged into the above melting furnace, and top blowing of an oxygen-containing gas is performed through a top-blown lance provided for the melting furnace, so that the solid reduced iron is melted by combustion heat obtained by combusting the carbon material and/or carbon in molten iron to form molten iron.
摘要:
A process for producing molten iron is a process in which while an inert gas is blown into a molten iron layer in an iron bath type melting furnace through bottom-blown tuyeres provided in a hearth bottom thereof to stir the molten iron layer, a carbon material, an additive flux, and solid reduced iron obtained by heating reduction of carbon composite iron oxide briquettes are charged into the above melting furnace, and top blowing of an oxygen-containing gas is performed through a top-blown lance provided for the melting furnace, so that the solid reduced iron is melted by combustion heat obtained by combusting the carbon material and/or carbon in molten iron to form molten iron. In addition, in this process for producing molten iron, the carbon material is charged so as to form a carbon material suspension slag layer in which the carbon material is suspended at an upper layer portion of a slag layer which is formed of slag generated when the solid reduced iron on the molten iron layer is melted into molten iron and further so as to form a carbon material covering layer made of only the carbon material on the carbon material suspension slag layer, and the molten iron and the slag accumulated in the melting furnace are discharged through a taphole provided at a lower portion of a furnace side of the melting furnace.
摘要:
An object of the present invention is to provide a method for reducing a chromium-containing material at a high chromium reduction degree. In the method of the present invention, a mixture of a feedstock containing chromium oxide and a carbonaceous reductant is heated and reduced by radiation heating in a moving hearth furnace. The average rate of raising the temperature of the mixture in the reduction is preferably 13.6° C./s or higher in the period from the initiation of the radiation heating of the mixture until the mixture reaches 1,114° C.
摘要:
The present invention provides a method for efficiently manufacturing a titanium oxide-containing slag from a material including titanium oxide and iron oxide, wherein a reduction of titanium dioxide is suppressed and the electric power consumption is minimized. The method includes the steps of: heating a raw material mixture including titanium oxide, iron oxide, and a carbonaceous reductant, or the raw material mixture further including a calcium oxide source, in a reducing furnace; reducing the iron oxide in the mixture to form reduced iron; feeding the resultant mixture to a heating melting furnace; heating the resultant mixture in the heating melting furnace to melt the reduced iron and separate the reduced iron from a titanium oxide-containing slag; and discharging and recovering the titanium oxide-containing slag out of the furnace.
摘要:
An object of the present invention is to provide a method for reducing a chromium-containing material at a high chromium reduction degree. In the method of the present invention, a mixture of a feedstock containing chromium oxide and a carbonaceous reductant is heated and reduced by radiation heating in a moving hearth furnace. The average rate of raising the temperature of the mixture in the reduction is preferably 13.96° C./s or higher in the period from the initiation of the radiation heating of the mixture until the mixture reaches 1,114° C.
摘要:
A method for producing molten iron by melting an iron source material using an iron bath-type melting furnace comprising a top-blowing lance at an upper part of the furnace, a bottom-blowing tuyere in the bottom of the furnace and a tap hole at a lower part on the side of the furnace, the method comprising: a melting process of charging the iron source material, a carbonaceous material and a flux into the furnace and top-blowing an oxygen-containing gas through the top-blowing lance while blowing an inert gas through the bottom-blowing tuyere into melt present in the furnace to stir the melt to thereby melt the iron source material and generate the molten iron and slag using combustion heat of combusting carbon in the carbonaceous material and/or in the molten iron, wherein the melting process has at least one tapping process of discharging the molten iron and the slag through the tap hole while holding a position of the furnace in generating the molten iron, and the tapping process continues or interrupts generation of the molten iron and continues top-blowing of the oxygen-containing gas to thereby keep a temperature of the molten iron in the furnace at or above a pre-set lowest temperature of the molten iron.
摘要:
The present invention provides a method for efficiently manufacturing a titanium oxide-containing slag from a material including titanium oxide and iron oxide, wherein a reduction of titanium dioxide is suppressed and the electric power consumption is minimized. The method includes the steps of: heating a raw material mixture including titanium oxide, iron oxide, and a carbonaceous reductant, or the raw material mixture further including a calcium oxide source, in a reducing furnace; reducing the iron oxide in the mixture to form reduced iron; feeding the resultant mixture to a heating melting furnace; heating the resultant mixture in the heating melting furnace to melt the reduced iron and separate the reduced iron from a titanium oxide-containing slag; and discharging and recovering the titanium oxide-containing slag out of the furnace.
摘要:
The present invention provides a process that is useful in producing ferronickel having a high Ni content at low cost with high efficiency and reproducibility even if a low-grade feedstock containing nickel oxide is used. In particular, a feedstock containing nickel oxide and iron oxide is mixed with a carbonaceous reductant, the mixture is formed into agglomerates with an agglomerator, and the agglomerates are heated and reduced in a moving hearth furnace, whereby reduced agglomerates in which the Ni metallization degree is 40% or more and the Fe metallization degree is at least 15% less than the Ni metallization degree are prepared by adjusting the retention time of the agglomerates placed in the moving hearth furnace. The reduced agglomerates, in which the Ni component has been primarily reduced as compared with the Fe component, are smelted in a smelting furnace, whereby ferronickel having a high Ni content is obtained.