A coaxial dual supersonic oxygen flow cluster oxygen lance comprises an inner layer circular-hole supersonic nozzle assembly, an outer layer water-cooled casting assembly, and a middle layer annular-hole supersonic nozzle assembly arranged between the inner layer circular-hole supersonic nozzle assembly and the outer layer water-cooled casting assembly, wherein the circular-hole supersonic assembly generates a first beam of supersonic oxygen jets and the annular-hole supersonic assembly generates a second beam of supersonic oxygen jets surrounding the first beam of supersonic oxygen jets; and the second beam of supersonic oxygen jets and the first beam of supersonic oxygen jets are in the same direction, and the two beams of supersonic oxygen jets are independently supplied with gas, and are independently adjusted. The oxygen lance can form coaxial dual supersonic oxygen flow, can flexibly adjust the flow of the oxygen lance under the condition of supersonic jets, and can meet the different requirements of an electric furnace at high steel scrap ratio for an oxygen system during smelting periods at different working conditions, thereby improving smelting efficiency of the electric furnace, reducing consumption and shortening smelting periods.

The present disclosure provides a converter CO.sub.2—O.sub.2 mixed injection smelting method and a fire point area temperature dynamic control method. The method realizes online monitoring through an infrared temperature sensor installed inside an oxygen lance, dynamically adjusts the mixing ratio of CO.sub.2 and O.sub.2 and the height of the oxygen lance position according to the fire point area temperature changes and process requirements in different smelting stages, so that the secondary smelting system interlockingly and dynamically controls the fire point area temperature and the molten pool heating rate.

The invention relates to a process for injecting particulate material into a liquid metal bath wherein the liquid metal bath contains species to be oxidized, wherein the particulate material is carried to the liquid bath by means of a first gas stream. The solids injection rate is controlled such that the liquid bath temperature and/or the evolution of the liquid bath temperature is maintained within a pre-defined temperature range and the penetration depth of the first gas stream into the liquid bath is controlled by adjusting the flow of the first gas stream. At least one second gas stream is injected into the liquid, wherein the first and the second gas streams are an oxidizing gas, in particular oxygen, and the sum of the gas flows of the first and the second gas streams is determined based on the mass of the species to be oxidized and on the desired time for oxidizing the mass of the species.

A multiple chamber material-stirring lance and method used to treat molten metal in a ladle, the lance having a stirring gas chamber, and a plurality of gas permeable ports arranged at a terminal end of the gas chamber, and at least one material chamber positioned parallel to the gas chamber and terminating in a plurality of material ports. In use, the multiple chamber material-stirring lance is lowered into the ladle of molten metal, and gas and material are both introduced into a respective chamber and emitted through their respective ports. Stirring gas emitted through the gas permeable ports under a gas pressure between 40 and 600 cfm causes the stirring gas to create a boiling effect in the molten metal, drawing material into the stirring gas bubbles and away from the lance body, improving material dispersion efficiency and thus impurity extraction from the molten metal.

When using oxygen gas pipes 3, situations can arise, in particular due to slag return and similar dangers, in which the operator must initiate safety measures. Slag return safety devices are known which, in such a case, ensure that the gas flow is stopped by melting a cap 35 of a heat sensor 5. The response of this outlet valve 6 of the slag return safety device can be recognized, for example, by the fact that the inlet pressure of the existing oxygen gas 4 is used to push pins 21 located in the wall 19 of the oxygen gas pipe 3 beyond the outside 27 of the oxygen gas pipe 3, so that they cannot be overlooked as a warning signal. The movement of the pins 21 can be used to activate further signal systems 30 in order to provide additional indications of this movement optically and/or acoustically.

An oxygen blowing lance comprising: a lance body including an oxygen conduit and cooling water inlet and outlet conduits surrounding said oxygen conduit; a lance head connected to said lance body and comprising a nozzle body, said nozzle body including a central strut having bore hole, a plurality of nozzles arranged about said central strut, and a plurality of cooling chambers arranged about said central strut, wherein said plurality of nozzles are in fluid communication with said oxygen conduit for discharging oxygen from said oxygen conduit onto a metal bath in a converter vessel, and wherein said plurality of cooling chambers are in fluid communication with said cooling water inlet and outlet conduits; a temperature probe or camera assembly received in said bore hole for monitoring the temperature of said lance head or molten heat in which the lance is inserted; signal lines connected to said temperature probe for conveying signals from said temperature probe whereby operation of said blowing lance is regulated in response to said signals; and a protective pipe pressurized with a gas disposed in the bore and surrounding said temperature probe assembly and the signal lines.

A long-life service method for powder-bottom-injecting converter based on collaborative hot replacement of furnace bottom and bottom purging brick belongs to the field of steelmaking technologies using powder-bottom-injecting converters. According to equipment characteristics, process characteristics, and erosion characteristics of the powder-bottom-injecting converter, the design, arrangement, installation, use, maintenance, and replacement of the bottom purging/powder injection bricks are systematically optimized and improved, a technology of automatically detecting the erosion height of bottom purging bricks is adopted, and hot replacement of bottom purging/powder injection bricks and hot replacement of the converter furnace bottom are used collaboratively, which not only can prolong the service life of a single bottom purging/powder injection brick, but also can greatly prolong the overall life of the powder-bottom-injecting converter from 1000-3000 heats in the prior art to 6000-10000 heats. Hence, the life of the powder-bottom-injecting converter is as long as that of a conventional converter.

The current invention refers to a blowing spear (100) used in the primary refining process for obtainment of steel, developed in such a way to maintain the loading and blowing operational conditions, comprising at the base a copper nozzle (101) to which is welded in its extremity a tube (102), comprising yet a module (125) with cleaning output (103) and positioned above module (125) a steel tube (118) and on its upper extremity, the head (107) that comprises a cooling liquid inlet (115), a gases inlet (116) and a cooling liquid outlet (117), comprising yet the spear (100) in its interior the inner tube (122) responsible for the gas passage and the intermediate tube (123) responsible for the division between the cooling liquid inlet flow and its outlet passing mandatorily through the copper nozzle (101).

A burner-lance unit (1) includes at least two gas connections (2a, 2b, 2c), a burner tube (3), and a lance tube (4) that is placed concentrically in the burner tube (3). The burner tube (3) and the lance tube (4) both have a gas inlet end and a gas outlet end (15). The lance tube (4) has a de Laval nozzle (4a) at the gas outlet end thereof. The de Laval nozzle (4a) is releasably connected to the lance tube (4). The burner tube (3) has a burner nozzle (3a) which is releasably connected to the burner tube (3).

A lance (10), for conducting a pyrometallurgical operation by top submerged lancing (TSL) injection, wherein the lance (10) has at least an inner pipe (12) and outer pipe (14) which are substantially concentric. The lower outlet of the inner pipe (12) is set at a level relative to the lower, outlet end of the outer pipe (14) required for pyrometallurgical operation. The lance (10) further includes a shroud (22) through which the outer pipe (14) extends and which is mounted on and extends along an upper portion of the outer pipe (14) to define with the outer pipe (14) a passageway (28) along which gas is able to be supplied for flow towards the outlet end of the outer pipe (14) for discharge exteriorly of the lance (10). The shroud (22) is longitudinally adjustable relative to the outer pipe (14) to enable substantial maintenance of, or variation in, a longitudinal spacing between the outlet ends of the shroud (22) and the outer pipe (14).