A method for reducing metal oxide containing charge materials (1): reducing the metal oxide containing charge materials (1) in at least two fluidized bed units (RA,RE) by means of a reduction gas (2), wherein at least some of the resulting off-gas (3) is recycled and wherein the metal oxide containing charge materials (1) are conveyed into the fluidized bed unit RE by a propellant gas. Also, apparatus for carrying out the method according to the invention is disclosed.

An apparatus for producing a bloated mineral granulate with a heated processing channel (1) for the mineral granulate fed to a conveying flow (13), wherein an inflow opening (4) is provided in the processing channel (1) for forming a granulate-free laminar flow (5) running along the inner wall of the processing channel, is described. In order to design a device of the type described above in such a way that a continuous, qualitatively controllable production process is achieved, it is proposed in that the processing channel (1) comprises two channel sections (16), (17) with differing cross-sections, wherein the channel section (16) with a smaller cross-section projects into the channel section (17) with a larger cross-section, forming the inflow opening (4), and wherein the channel section (16) with a smaller cross-section is enclosed by the channel section (17) with a larger cross-section in such a way that an inflow opening (4) is formed completely around the projecting region of the channel section (16) with a smaller cross-section.

A fluid assisted particle injector for a metallurgical furnace, comprising: an injector tube having an entrance end, an exit end and a removable tip; a cover tube disposed over the injector tube; a fluid and particle injector port in line with the longitudinal center axis of the injector tube and a secondary fluid port for directing pressurized fluid over the outside of the injector tube and within the cover tube; the injector tube defining a tapered internal bore having a particle entrance end and a particle exit end, wherein the diameter of the particle exit end is smaller than the diameter of the particle entrance end.

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.

Provided are a method and an arrangement for adjusting characteristics of a furnace process in a furnace space limited by a furnace shell of a metallurgical furnace. The arrangement comprises an injection unit having a frame mounted by means of a mounting means on the metallurgical furnace outside the furnace space of the furnace shell. Also provided is an injection unit for use in the method and in the arrangement.

A cooling system for use in support of a pyro-metallurgical furnace includes a liquid heat transfer fluid blend of 10%-50% water with monoethylene glycol (MEG), diethylene glycol (DEG), or triethylene glycol (TEG), and corrosion inhibitors. When using such glycols, a minimum of 10% water prevents the heat transfer fluid from becoming too viscous for economical pumping, and a maximum of 50% water prevents BLEVE incidents inside the furnace. Such intrinsically safe cooling system circulates the liquid heat transfer fluid blend with an optimally sized pump, filtration, pressurization, and at flow velocities sufficient to avoid film boiling.

The invention relates to a method for producing an expanded granulate (29) made of a sand grain-shaped mineral material (1) using a propellant; wherein the material (1) is fed to a substantially upright furnace (2); wherein the material (1) is conveyed along a conveying path (4) through a plurality of vertically separated healing zones (5) in a furnace shaft (3) of the furnace (2), wherein each heating zone (5) can be heated by at least one independently controllable heating element (6); wherein the material (1) is heated to a critical temperature at which the surfaces (7) of the sand grains (1) become plastic and the sand grains (1) are expanded through the propellant. It is provided according to the invention that the material (1) is fed together with an amount of air from below, wherein the material (1) is conveyed from bottom to top along the conveying path (4) by means of the amount of air which flows from bottom to top within the furnace shaft (3) and forms an air flow (14), and wherein the expanding of the sand grains (1) occurs in the upper half, preferably in the uppermost third, of the conveying path (4).

A method of operating a blast furnace by blowing a pulverized coal at an amount of not less than 150 kg/tp from tuyeres through a lance into a blast furnace, wherein when the operation is performed under a condition that lump coke charged from a furnace top has a strength defined in JIS K2151 (DI.sup.150.sub.15) of not more than 87%, the pulverized coal blown through the tuyere contains not more than 60 mass % as a weight ratio of coal having a particle size of not more than 74 m and has an average volatile matter of not more than 25 mass %, and a blast temperature blown through the tuyere is not higher than 1100 C., oxygen is simultaneously blown into the furnace with the blowing of the pulverized coals through the lance and a gas having an oxygen concentration of 60 vol %-97 vol % is used as a carrier gas for the blowing of the pulverized coal.

A method for manufacturing pig iron in an electrical smelting furnace including a vessel, the method including the following successive steps: loading DRI product in the vessel, melting the DRI product to form a pig iron layer topped by a slag layer, and injecting a desulphurizing reagent directly in the pig iron layer. It also deals with the manufacturing of steel from the pig iron and the associated electrical smelting furnace.