Abstract: A method for manufacturing coal agglomerates for use in a direct smelting reducing furnace is disclosed, in which a fine coal is agglomerated at a high temperature in a simple manner, or anthracite or low free swelling coal having a low free swelling index is mixed with the fine coal, and the mixture is agglomerated at a high temperature, thereby turning the low quality coal to useful purpose. The present invention is characterized in that a fine coal having a free swelling index of 3.0 or more and a particle size of 8 mm or less, or the fine coal mixed with 70 weight % of anthracite or a low free swelling coal, is maintained at 600.degree. C. or over for 5 minutes or more, thereby manufacturing coal agglomerates for use in a direct smelting reducing furnace.

Abstract: A method for aging steel-making slag comprising the steps of charging normal temperature steel-making slag crushed to the extent that the slag having a grain diameter of 25 mm or less which constitutes 80% or more of the total amount into a pressure vessel which can be closed tight enough to seal a pressure substantially higher than atmosphere. The pressure vessel is closed and pressureized steam is supplied into the said vessel for heating the said pressure vessel and slag to raise the temperature and the pressure in the said pressure vessel while discharging condensed hot water. The interior of the vessel is kept under a condition saturated by steam and pressurized up to 2 to 10 kg/cm.sup.2 G for 1 to 5 hours. The pressure in the pressure vessel is reduced to be equalized with atmosphere. The steel-making slag is then discharged from the vessel. Apparatus is provided for carrying out the above process and includes a pressure vessel having an opening lid for charging and discharging steel-making slag.

Abstract: A stable aqueous solution comprising a water soluble salt of a magnesium compound, a surfactant and a calcium salt inhibitor is used to reduce deposits in kilns or furnaces used to make iron ore agglomerates, known as pellets, during iron ore calcination.

Abstract: Improvements in metallurgical conversion in accordance with the present intion consist in the preparation of a semifinished item (a charge stock) in the form of a pig by forming thereof in a molding box of a casting machine from a solid filler, for the most part an oxidizing agent, and a liquid pig iron followed by cooling, provided said solid filler and said liquid pig iron undergo, in the process of forming, an action which prevents the floating up of the solid filler in the liquid pig iron. Such an action is effected both by applying a mechanical force, in particular by providing a casting machine with a cantilever (8) having a hollow roller (9) which rests on a molding box (2) and a weighting material (10), and by choosing relative dimensions of the solid filler pieces and selecting a rate of pig casting. Optimal conditions for using such semifinished item for metallurgical conversion which in accordance with the present invention is carried out in oxygen converters and arc furnaces are described.

Abstract: A method of stabilizing a fluidized bed in a fluidized bed roasting process for metal sulphide concentrate comprises the step of controlling the particle size distribution of the particulate material in the bed so that a minimum amount of no less than about 30% of the concentrate falls in a size range of from about 100 to about 420 microns. The minimum amount preferably falls in the range of from about 35% to about 40%. In one embodiment of the invention the particle size distribution is controlled by maintaining the amount of lead in the concentrate in a range from about 3% to about 4%, preferably 3.7% to about 3.8%. In another embodiment the particle size distribution is controlled by using a pelletized feed or by the combination of the steps of using a pelletized feed and regulating the lead content of the concentrate.

Abstract: The invention is directed to a process for dehydrating wet BOF scrubber sludge to produce a steelmaking revert having an improved flow rate when handled in a recycle stream. Wet sludge is combined with hot BOF slag to provide a slag/sludge mixture. The wet sludge causes the mixture to have a moisture content greater than 10% water by weight, and the hot slag, having a temperature below the molten liquid state, vaporizes the water in the mixture and reduces the moisture content to about 4% water by weight or less. The dehydrated mixture has improved flow rate properties when it is recycled as a steelmaking revert.

Abstract: A composite charge for metallurgical processing which reduces the content of non-metallic inclusions in the end product(s) comprises 40-83 wt. % of a metallic agent, 17-50 wt. % of an oxide agent and 0.1-10.0 wt. % of a carbonaceous agent. The carbonaceous agent includes a mixture of metal carbides and free carbon, preferably graphite, having a ratio in the range of 0.1-10.0:1.

Abstract: A method for agglomerating iron ore particles pre-reduced to produce hot pig iron, wherein hot iron ore particles pre-reduced in the pre-reduction furnace are simply mixed with aluminum powder or aluminum-containing metal powder before being loaded in the smelting reduction furnace so that they will be agglomerated, thereby being capable of not only simplifying the agglomeration, but also eliminating the adverse effect on the quality of ingot iron caused by impurities such as S or P. Aluminum dross, which is a waste, may be used as the aluminum-containing metal powder for agglomerating the iron ore particles. In this case, a reduced energy consumption and disposal of wastes can be achieved.

Abstract: The present invention relates to a method for making sponge iron briquettes from fine ore with a maximum grain size of less than 2 mm, preferably less than 0.5 mm, wherein hot fine ore is fed to a roller press comprising two press rolls and is briquetted by opposite briquette pockets of the press rolls in the nip to form sponge iron briquettes. The direct pressing of fine ore into sponge iron briquettes has largely been unknown in the prior art. The invention proposes that one of the press rolls be operated as a loose roll which is substantially movable in a direction transverse to the roller axis, the nip adapting to the amount of material supplied to the press rolls and the nip substantially having such a mean width that a briquette strip is produced. In comparison with a former method, the method of the invention achieves a markedly increased service life of the molding bodies which are provided with press pockets.

Abstract: A stable aqueous solution comprising a water soluble salt of a magnesium compound is used to reduce deposits in kilns or furnaces used to make iron ore agglomerates, known as pellets, during iron ore calcination.

Abstract: A method of producing direct reduced iron from pellets, lumps and fines of iron oxide. A mixture of iron oxide raw material is introduced to an apparatus which separates the lumps and pellets from the fines. The lumps and pellets are then introduced to a shaft furnace for direct reduction to iron. Fines are conveyed to a series of circulating fluidizable beds which allows intimate contact with reducing gas to facilitate the direct reduction of the iron oxide fines to metallized iron.

Abstract: An improved method of extracting minerals from ore is described. The method is applicable to vat leaching operations and may also be useful in heap leaching operations. The method involves the pre-heating of comminuted ore prior to the agglomeration phase. The method is found to improve the quality of the agglomerate and to reduce the curing cycle time. In addition, the method described herein induces extra heat into the agglomerated mass which, as well as enhancing the agglomerate quality, adds heat to the leach solution resulting in higher mineral recoveries. The method is especially useful in the winter months when ore temperatures are low; however, improved results are realized when the method is used in the summer months as well.

Abstract: The present invention is concerned with a process for the preparation of sintered calcium aluminates that can generally be used as a protective cover for liquid metals, and particularly steel, and the process comprising the steps of mixing calcium oxide, or its precursor, particles and aluminum dross residue, such as NOVAL.TM.; calcining the resulting mixture; maintaining a calcining temperature of 1200.degree. C. or higher for approximately 5 minutes or more which is sufficient to form a friable sintered product rich in calcium aluminates; and recovering the sintered product after cooling. Optionally, calcium fluoride, or other fluoride can be added to the starting mixture, if it is not already contained in the dross residue.

Abstract: A process for consuming oily sludge waste product in steel making operations includes spraying a waste slurry onto the moving porous bed of a sinter strand. A burner hood is spaced above a portion of the moving bed. The bed carries a sinter mix which is ignited in the ignition zone of the burner hood and the slurry is sprayed onto the ignited sinter mix immediately downstream of the ignition zone. A vacuum system draws the slurry through the ignited sinter mix ensuring substantially complete combustion of the slurry.

Abstract: The invention relates to the reprocessing of used evaporation boats. This is done by a method which comprises comminuting used, aluminum-contaminated evaporation boats and roasting them in a nitrogen-containing atmosphere.

Abstract: A method and apparatus for sintering a mixture of finely divided ore and a solid reductant, preferably in agglomerated form, includes heating the mixture on a hearth (6) with radiant energy in the form of infra red radiation from an infra red source such as infra red lamps (4, 5) to a sufficient temperature to induce ignition of the reductant. The hearth (6) is formed by a moving perforated conveyor surface (2) in which the material to be sintered is disposed for heating by the lamps. Below the hearth is a duct (3) connected to a vacuum source for drawing air through the hearth and material thereon.

Abstract: A method and device for the economic and environmentally safe disposal of waste material and molten slag from a cupola furnace comprises admixing the waste material with either molten slag or granulated slag so as to form a homogeneous mixture of the waste material in the slag material and thereafter feeding the mixture to a collection container.

Abstract: Composite powders containing a first group of metals of iron, cobalt, nickel and molybdenum in specific ratios and one or more oxidizable metals can be formed by forming an aqueous solution containing first group of metals, forming solid material of the metals from the solution, reducing the solid material to a metallic powder, combining that powder with one or more easily oxidizable metals in an non-oxidizing atmosphere.

Abstract: Spent oxidic catalyst, such as vanadium pentoxide from a sulphuric acid manfacturing process, is rendered into an environmentally acceptable non-leachable form suitable for disposable by incorporation into a vitrified amorphous slag formed of oxidic slag forming agents such as CaO, SiO.sub.2, FeO and Al.sub.2 O.sub.3. The vitrified slag may be formed as part of a conventional ferrous or non-ferrous smelting process, or may employ a pre-existing slag from such a process.

Abstract: A method is disclosed for controlling the level of oxygen in molybdenum metal powder, which comprises agglomerating and sintering the molybdenum powder, classifying the resulting agglomerated and sintered molybdenum powder to obtain a particle size of from about -200 to about +325 mesh, contacting the resulting classified powder with a sufficient amount of an aqueous solution of hydrogen peroxide containing from about 1% to about 10% by weight of hydrogen peroxide to yield a molar ratio of H.sub.2 O.sub.2 :Mo of from about 2 to about 5 for sufficient time to achieve an oxygen content in the powder of from about 1% to about 15% by weight wherein the major portion of the oxygen is on the surface of the agglomerates, and removing the resulting hydrogen peroxide-treated molybdenum powder agglomerates from the resulting solution.