Abstract: The invention relates to a method of integrating a plurality of blast furnaces with a plurality of air gas separation units, in which the replacement blower available on the blast furnace site is used to feed compressed air into an air gas separation unit making it possible to enrich the blast-furnace blast with oxygen, this unit being stopped when one of the blowers of the blast furnaces has to be replaced with the blower used by the air gas separation unit.

Abstract: The invention relates to a method and device for supersonically injecting oxygen into a furnace, in particular a cupola furnace, in which the total oxygen required for the furnace operation is injected with the aid of two distinct circuits, i.e., the first circuit comprising at least one supersonic oxygen injecting nozzle and a second circuit which comprises additionally oxygen injecting means and is connected to the first circuit by pressure-sensitive means, such as a discharging device (or upstream pressure adjuster), in such a way that a stable pressure is obtained in the first circuit upon the attainment of the maximum flowrate thereof, wherein the first circuit can consists of several supersonic nozzle groups.

Abstract: A process for direct smelting metalliferous feed material in a direct smelting vessel and producing process outputs of molten metal, molten slag, and an off-gas from the vessel is disclosed. The process includes controlling pressure in the direct smelting vessel by controlling off-gas pressure in an off-gas stream supplied to a fluidised bed pretreatment apparatus while the process is operating in the “hold” and “idle” process states.

Abstract: A ferroalloy, particularly stainless steel, is made by melting typically low-carbon steel under foamy slag conditions, and refining the molten steel at least in part by blowing molecular oxygen into the molten steel from a lance positioned above its surface. During the refining step at least one metallurgically acceptable particulate material is introduced into the molten steel. The particulate material is selected from chromium metal, chromium-containing alloys and chromium ores.

Abstract: The invention relates to a method and device for supersonically injecting oxygen into a furnace, in particular a cupola furnace, in which the total oxygen required for the furnace operation is injected with the aid of two distinct circuits, i.e., the first circuit comprising at least one supersonic oxygen injecting nozzle and a second circuit which comprises additionally oxygen injecting means and is connected to the first circuit by pressure-sensitive means, such as a discharging device (or upstream pressure adjuster), in such a way that a stable pressure is obtained in the first circuit upon the attainment of the maximum flowrate thereof, wherein the first circuit can consists of several supersonic nozzle groups.

Abstract: The present invention generally relates to processes and apparatuses for the integration of a blast furnace and an air separation plant to increase blast furnace production. The present invention recovers energy from the air separation through the expansion of a product stream.

Abstract: A method for the separation of a feed gas mixture comprising oxygen and nitrogen in which an oxidant gas and fuel are combusted in a combustion engine to generate shaft work and a hot exhaust gas, the feed gas mixture comprising oxygen and nitrogen is compressed, and the resulting compressed feed gas mixture is separated into two or more product gas streams with differing compositions. The shaft work of the combustion engine is utilized to provide at least a portion of the work required for compressing the feed gas mixture, one of the product gas streams by is heated by indirect heat exchange with the hot exhaust gas from the combustion engine, and the resulting heated product gas is work expanded to generate shaft work and yield an expanded product gas stream. The combustion engine may be a gas turbine combustion engine.

Abstract: A method for reducing the NOx content of combustion gases from combustion in a commercial furnace wherein hot oxygen and carbonaceous fuel such as pulverized coal react to form a fuel-rich gas phase mixture which is then used to reduce NOx to nitrogen gas.

Abstract: A method wherein air is separated in an air separation unit (9), the oxygen thus generated is consumed during at least one step (2, 12, 13) of the steel-making process, the resulting gas is at least partially decarbonated, and the at least partially decarbonated gas is used (at 13) in a reduction reaction of the steel-making process. The partial decarbonation step cyclically includes a CO.sub.2 fixation step using a fixation agent, and a regeneration step in which the agent is regenerated in a reactor. Nitrogen generated by the air separation unit (9) is fed into the reactor during the fixation agent regeneration step. The method is useful in combined coal gassification/direct iron ore reduction processes.

Abstract: A method for providing a blast stream into a blast furnace wherein fuel and hot oxygen are provided into the blast air, the hot oxygen being at a temperature and velocity each greater than that of the blast air, and wherein the fuel and hot oxygen begin to combust prior to passage into the blast furnace in the blast stream.

Abstract: A gas-consuming unit (HF) is fed partially by a flow delivered directly by a compression unit (21) and partially by one delivered by a separation apparatus (25) which is itself fed by a flow delivered directly by the compression unit. Another flow produced by the separation apparatus, but at lower pressure, is returned to a compression unit before being sent to the consumer unit.

Abstract: A method for increasing iron production by integrating blast furnace ironmaking with direct reduction ironmaking wherein cryogenic rectification links the two systems and produces input materials for both.

Abstract: A method of supplying both an oxygen steelmaking process and an ironmaking process with oxygen. The oxygen is separated from air by rectification of the air. A first stream of oxygen from the rectification to the steelmaking process. A second stream of oxygen is also supplied from the rectification to the ironmaking process. The first and second streams of oxygen are both withdrawn from essentially the same stage of the rectification and both contain from about 97 to about 98% by volume of oxygen and less than about 100 parts per million of nitrogen.

Abstract: A process for producing pig iron from iron ore fines wherein the fines are partially reduced in a fluid bed reactor and, without pelletizing, briquetting or otherwise agglomerating the partially reduced fines, injecting them with a lance below the surface of a bath of a submerged arc furnace.

Abstract: The combined installation comprises at least one metal production unit (II), including at least one, and typically a series of metal production or treatment units (1-6), and at least one air gas separation unit (III) including at least one outlet for at least one air gas (14-18), the units being supplied with compressed air with a low water vapor content by a common compressed air production unit (I), and with at least one of the gas outlets (14-18) from the separation unit (III) connected to at least one of the devices (1-6) of the production unit, to supply the latter with gas.

Abstract: A high-speed jet of liquid oxygen (21) with a speed higher than 100 meters per second is delivered into the tuyeres of a blast furnace of cupola furnace together with pulverised carbon. The jet reaches the opposite wall of the cavity (9) formed at the outlet of the tuyere (6) in the mass of material contained in the shaft. Supplying oxygen to the bottom of the cavity improves the burning of the remaining coal, whereby higher injection levels may be achieved. The shape of the cavity may also be altered, and, in particular, faster reactions may be achieved in the axial region of the shaft.

Abstract: In a process integration, particularly with a blast furnace, nitrogen under pressure is moisturized by the addition to it of hot, pressurized water. The moisturized nitrogen is expanded and power thereby generated. The nitrogen is not mixed with combustion gases. Improved heat balance and work recovery are achieved.

Abstract: In a process integration, particularly with a blast furnace, low grade fuel gas produced by the furnace is compressed and moisturized. The moisturized fuel is burnt using a major part of a compressed air stream to support its combustion. The resulting combustion gases are then expanded with the generation of power. The minor part of the air is separated into oxygen and nitrogen. Oxygen is used in the blast furnace.

Abstract: Air is taken from the air compressor of a gas turbine including in addition to the compressor a combustion chamber and an expansion turbine. The gas turbine drives an alternator. The air taken from the compressor is cooled in heat exchanger to remove heat of compression therefrom. The air is separated in an air separation plant into oxygen and nitrogen. A stream of oxygen is withdrawn from the plant and used in a blast furnace in which iron is made. The off-gas from the blast furnace is a low grade gaseous fuel. It is compressed in compressor which has interstage cooling to remove at least some of the heat of compression. The compressed fuel gas is passed through the heat exchanger countercurrently to the air stream. The resulting pre-heated fuel gas flows into the combustion chamber of the gas turbine and is burned therein to generate gaseous combustion products that are expanded in the turbine. A nitrogen stream is withdrawn in the air separation plant.

Abstract: There is produced by an air distillation apparatus (4) a desired fraction of air from the stream of air leaving at least one blower (3) of the blast furnace, and there is sent to the blast furnace the oxygen produced by this distillation apparatus. The distillation apparatus comprises an air/liquid oxygen mixing column which operates at about 1 bar above the delivery pressure of the blower (3) and which directly produces the oxygen for enriching the air.

Abstract: A method for manufacturing a chromium-bearing pig iron comprises the steps of charging cold bond pellets, iron ore and coke lumps into a blast furnace from above and blowing a gas containing more than 50% oxygen therein and tuyere nose flame temperature control agent into the blast furnace through the tuyere, the cold bond pellets being comprised of powdered chromium ore and powdered coke as principal feed materials. The cold bond pellets are manufactured by performing a mixing, a pelletizing and a curing step. The tuyere nose flame temperature control agent is a top gas, steam, water or CO.sub.2, which is used to control the flame temperature to 2000.degree. to 2900.degree. C.

Abstract: According to a method of operating a blast furnace, pure oxygen, pulverized coal, and a temperature control gas which substantially does not contain nitrogen are blown from tuyeres. A preheating gas which substantially does not contain nitrogen is blown from an intermediate shaft level. A blast furnace gas which substantially does not contain nitrogen can be produced from a furnace top.

Abstract: The combined installation comprises at least one metal production unit (II), including at least one, and typically a series of metal production or treatment units (1-6), and at least one air gas separation unit (III) including at least one outlet for at least one air gas (14-18), the units being supplied with compressed air with a low water vapor content by a common compressed air production unit (I), and with at least one of the gas outlets (14-18) from the separation unit (III) connected to at least one of the devices (1-6) of the production unit, to supply the latter with gas.