摘要:
Smelting metalliferous feed material process forming molten metal in smelting apparatus including smelt cyclone above and communicating with smelting vessel to contain molten metal and slag bath, including: partially reducing and melting feed material in smelt cyclone, allowing the molten partially reduced feed material flow downwardly into vessel, supplying oxygen-containing gas and carbonaceous material to vessel, smelting molten partially reduced feed material in molten metal and slag bath in vessel forming molten metal discharged from vessel and reaction products projected upwardly from molten bath, at least partially combusting combustible materials in reaction products in vessel space above molten bath, supplying oxygen-containing gas to smelt cyclone. Further combusting reaction products in smelt cyclone, discharging from smelt cyclone offgas including reaction products, supplying oxygen-containing gas into offgas duct upstream high temperature section combusting remaining offgas combustible materials while sufficiently hot for safe ignition and avoiding downstream burner-managed incineration.
摘要:
A rotary hearth furnace includes: a furnace body which surrounds a ring-like space; a hearth portion which forms a bottom portion of the ring-like space and is rotatable in the rotational direction; a gas exhaust portion which discharges an exhaust gas generated in the ring-like space to the outside of the furnace body; an introducing portion; and a flow rate regulating portion. The introducing portion is disposed upstream of the gas exhaust portion in the rotational direction and introduces a pressure regulating gas into a non-heating section of the ring-like space. The flow rate regulating portion is disposed between the introducing portion and the gas exhaust portion and regulates a flow rate of a gas by adjusting an opening area of the non-heating section.
摘要:
Provided is a device for producing partially reduced iron, with which partially reduced iron having a prescribed reduction ratio can be produced efficiently. The present invention is equipped with: CO sensors that detect the carbon monoxide concentration in an exhaust gas; an O2 sensor that detects the oxygen concentration in an exhaust gas; an exhaust gas circulation device that adjusts the circulating amount of the exhaust gas supplied to a reduction furnace main body, and an air feed device that adjusts the amount of air that being fed; and a control device that controls these devices. The control devices on the basis of the carbon monoxide concentration in the exhaust gas as detected by the CO sensor and the oxygen concentration in the exhaust gas as detected by the O2 sensor.
摘要:
A method of operating a smelt cyclone, wherein the supply of feed material and/or the supply of oxygen containing gas through an array of tuyeres into the smelt cyclone is controlled in order to control accretions of metalliferous feed material at the inside of the smelt cyclone.
摘要:
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.
摘要:
A method and a device for charging a plurality of reduced iron raw materials into a traveling hearth reduction-melting furnace and treating the raw materials, allowing sufficient input of heat to the reduced iron raw materials on a hearth covering material to improve treatment efficiency are provided. The reduced iron raw materials are released downward from the lower surface of a ceiling of the reduction-melting furnace to be set on a hearth covering material on a hearth and reduced on the hearth covering material. The falling reduced iron raw materials are given a horizontal velocity having a direction equal to the travel direction of the hearth and being greater than the travel speed of the hearth to enable the reduced iron raw materials to roll in the same direction as the travel direction of the hearth after landing on the hearth covering material.
摘要:
A rotary hearth furnace includes a unit that supplies an agglomerate onto a hearth of the rotary hearth furnace, a unit that discharges a heated substance which has been heated in the rotary hearth furnace to the outside of the furnace, and a unit that discharges an exhaust gas in the rotary hearth furnace to the outside of the furnace. The rotary hearth furnace has a heating section and a non-heating section. The unit that discharges an exhaust gas to the outside of the furnace is provided in the non-heating section. A unit that takes an outside air into the furnace is provided in the non-heating section and on an upstream side in a flow direction of the exhaust gas from the unit that discharges exhaust gas to the outside of the furnace.
摘要:
Disclosed is a production device of which secondary combustion efficiency can be further improved when a molten metal is produced by directly reducing and melting a metal agglomerate raw material layer in an electric heating furnace. Specifically, material charging chutes (4, 4) are disposed at either end portion (2, 2) of a furnace in the width direction of the furnace. Electrodes (5) are disposed in a central region in the furnace width direction. Secondary combustion burners (6) are disposed in an upper portion (1) of the furnace having stepped portions descending from both end portions (2, 2) in the furnace width direction to the electrodes (5). Raw material layers (12) each having a downslope inclined to lower portions of the electrodes (5) are formed in advance by charging a carbonaceous material (A) from the chutes (4, 4), and metal agglomerate raw material layers (13) are formed on the slopes of the raw material layers (12) by charging metal agglomerate raw material (B). Molten iron is produced by sequentially melting lower end portions of the metal agglomerate raw material layers (13) by arc heating at the electrodes (5). At the same time, an oxygen containing gas (C) is blown from the secondary combustion burners (6) so as to cause the combustion of a CO containing gas generated from the metal agglomerate raw material layers (13) while the metal agglomerate raw material layers (13) descend along the slopes of the raw material layers (12), and the metal agglomerate raw material layers (13) are heated by the radiant heat of the combustion.
摘要:
The first purpose of the present invention is to provide a method for producing metallic iron, whereby, in the production of metallic iron by heating an agglomerate, which comprises an iron oxide-containing material and a carbonaceous reductant, in a movable hearth type heating furnace, metallic iron can be efficiently collected from a reduced product containing metallic iron and a slag, said reduced product being obtained by heating the agglomerate. The method for producing metallic iron according to the first embodiment of the present invention comprises: a step for forming an agglomerate of a mixture which comprises an iron oxide-containing material and a carbonaceous reductant; a step for introducing the obtained agglomerate into a movable hearth type heating furnace and reducing the same by heating; a step for crushing a reduced product containing metallic iron and a slag, said reduced product being discharged from the movable hearth type heating furnace, using an impact crusher; and a step for selecting and collecting the metallic iron using a separator.
摘要:
A method for use in production of metallic iron nodules comprising providing a reducible mixture into a hearth furnace for the production of metallic iron nodules, where the reducible mixture comprises a quantity of reducible iron bearing material, a quantity of first carbonaceous reducing material of a size less than about 28 mesh of an amount between about 65 percent and about 95 percent of a stoichiometric amount necessary for complete iron reduction of the reducible iron bearing material, and a quantity of second carbonaceous reducing material with an average particle size greater than average particle size of the first carbonaceous reducing material and a size between about 3 mesh and about 48 mesh of an amount between about 20 percent and about 60 percent of a stoichiometric amount of necessary for complete iron reduction of the reducible iron bearing material.