metallurgical burner for use in a metallurgical furnace and method for operation of a metallurgical furnace, especially with such a burner

摘要

1,273,629. Burners. AIR PRODUCTS & CHEMICALS Inc. 22 May, 1969 [29 May, 1968], No. 26214/69 Heading F4T. A metallurgical burner for use in a metallurgical furnace comprises an outer water cooled jacket 10 terminating in a shaped ring portion 26, central conduits 58, 70, for a water cooled bluff body 60, and an intermediate sleeve 40 terminating upstream of the ring 26 and body 60 in a shaped water cooled ring 42, thereby defining passages 48, 49 for fuel e.g. natural gas and oxygen, or vice versa, ending in annular nozzles 76, 80 respectively, in fluid communication with an annular flame orifice 82, and is characterized in that the sleeve 40 and body 60 are parts of a central portion 12 which can be moved longitudinally relative to the jacket 10, e.g. by hydraulic means to vary the flame shape. In use the velocity of gas issuing from nozzle 80 must be greater than that from nozzle 76. As portion 12 moves upstream relative to the jacket from a position wherein frusto-conical surfaces 54 and 34 on rings 42 and 26 respectively are aligned, when the looanda effect is operative to give an umbrella shaped flame, the flame changes to ball shaped and finally to pencil shaped as a cylindrical surface 30 on the ring 26 becomes effective to deflect flow from the nozzle 80. As shown, the ring 26 includes a sharp edge 38 for detachment of the fuel-oxygen flow when an umbrella flame is produced, but the edge may be rounded to give a reverse direction flow and a flatter umbrella. The body 60 incorporates a frustoconical surface 64 with a generating angle /2 of 45-75 degrees, preferably 60 degrees. It is preferred that water is supplied initially to the outer section of jacket 10 and returned via the inner section, although flow in either direction is possible. By shutting off the fuel supply, the burner may be used as an oxygen lance.