Abstract: A tuyere for the injection of both a refining gas such as oxygen into a melting or refining vessel, and a fluid protective medium such as a hydrocarbon gas or a liquid surrounding the injected refining gas, in which there is a solid center in the pipe through which the refining gas is suplied so that the refining gas enters the refining vessel as an annulus around which the protective fluid is disposed.The tuyere is installd in the refractory lining of the refining vessel and the fluids passing into the vessel through the tuyere are proportioned so that burning back of the tuyere and erosion or wear of the lining take place at the same rate.The protective medium cools the tuyere and avoids reactions between the refining gas and the tuyere material.

Abstract: A procedure is described for supplying thermal energy to a steel melt by burning a fuel in a melt containing at most 0.10% carbon, by means of oxygen. Both the fuel and the oxygen are introduced into the steel melt beneath the surface of the melt. The method permits an increase in the scrap or other iron carriers, (ore, pellets, etc.) which can be processed. Apparatus for carrying out the process is also described.

Abstract: This application describes a process and apparatus for gasifying sulphur bearing coal in a molten iron bath which is covered with a sulphur absorbing slag. In order to make the process practical, the hot liquid slag is transferred to a second vessel in which it is desulfurized by contact with an oxygen containing gas, and then returned as hot liquid slag to the iron bath for reuse.

Abstract: A process for continuous refining in which liquid pig iron is supplied to a pig iron melt which is at least partially refined while said melt is being intensively agitated, the refining means (preferably oxygen) is introduced into the pig iron melt by means of tuyeres mounted in the refining vessel, and discharging the refining means beneath the surface of thepig iron melt, the tuyeres being positioned and the refining means being furnished so that the kinetic energy of the refining means contributes to the bath agitation. The tuyeres are preferably composite tuyeres like those described in U.S. Pat. Nos. 3,706,549 issued Dec. 19, 1972 and 3,771,998 issued Nov. 13, 1973, for discharging oxygen surrounded by a gaseous and/or liquid hydrocarbon, and possibly lime or other solid powder into the bath.

Abstract: An improvement in the refining of molten metals in a converter by means of oxygen introduced into the metal through tuyeres which include two concentric pipes, oxygen being passed into the melt through the central pipe and a protective fluid being passed into the melt as a sheath or screen around the oxygen, through the clearance space between the two pipes. In the present invention two tuyeres, disposed horizontally and each passing through the convertor sidewall permit refining to be accomplished without any slopping or splashing of the melt and with only minor wear of the convertor lining.

Abstract: An increase in the life of basic refractory linings in hearth type refining furnaces and a decrease in tap-to-tap time is achieved by the use of at least one refining tuyere which consists of two concentric pipes. The central pipe feeds oxygen into the melt below the bath surface, and a hydrocarbon stream surrounds the oxygen being fed into the bath, the hydrocarbon flowing in the space between the two pipes. Preferably the tuyere is embedded in the furnace backwall and is approximately horizontal and is directed toward the center of the hearth. By use of the double tuyere, oxygen can be used for refining without experiencing excessive refractory wear.

Abstract: Pig-iron is refined into steel by blowing oxygen and a protective screen of an encasing gas through injecting means located at or near the bottom of a converter containing a melt of molten metal. The encasing gas while protecting the injecting means, allows it to be consumed at substantially the same rate as the bottom of the converter so that the injecting means is not left projecting from the bottom of the converter. The encasing gas can be one which is inert to the melt or the metal of the injecting means or both, or it can be a gas which reacts sluggishly with the melt or the material of the oxygen feed pipe or both. Desirably, the oxygen jet is circular in cross-section and the encasing gas is in the form of a concentric jet.A converter for carrying out the method is made up of a pear-shaped sheet-steel casing having a refractory lining and an inserted bottom provided with nozzles in the form of metal tubes for the oxygen and encasing gas.

Abstract: Pig-iron is refined into steel by blowing oxygen and a protective screen of an encasing gas through injecting means located at or near the bottom of a converter containing a melt of molten metal. The encasing gas while protecting the injecting means, allows it to be consumed at substantially the same rate as the bottom of the converter so that the injecting means is not left projecting from the bottom of the converter. The encasing gas can be one which is inert to the melt or the metal of the injecting means or both, or it can be a gas which reacts sluggishly with the melt or the material of the oxygen feed pipe or both. Desirably, the oxygen jet is circular in cross-section and the encasing gas is in the form of a concentric jet.A converter for carrying out the method is made up of a pear-shaped sheet-steel casing having a refractory lining and an inserted bottom provided with nozzles in the form of metal tubes for the oxygen and encasing gas.