GB1534788A - Tuyeres for smelting shaft furnaces - Google Patents

Abstract

1534788 Tuyeres burners CREUSOT-LOIRE 27 July 1976 [14 Aug 1975 21 Oct 1975] 31319/76 Heading F4B and F4T In a blast furnace tuyere comprising three concentric conduits 5, 7 and 8, hot blast is fed through the central conduit 5, an unheated oxidizing gas, such as oxygen-enriched air, oxygen and water vapour, oxygen and carbon dioxide, or pure oxygen, is fed through the intermediate conduit, and a fluid or emulsion containing hydrocarbons is fed through the outer conduit. Powdered chalk or limestone may also be introduced into the blast furnace in suspension in the oxidizing gas flow, if required for slagging purposes. As shown in Fig. 1 cold pure oxygen is introduced tangentially into the intermediate conduit through an inlet 19, and hydrocarbon fluid tangentially into the outer conduit through inlet 20. The central conduit is of stainless steel, lined with a layer of cast refractory concrete 6, the intermediate conduit 7 of copper and the outer conduit 8 of steel. Hot blast is supplied to the central conduit 5 through a pipe 13. The ends of conduits 5, 7 and 8 project different distances into the blast furnace. When the delivery of oxidizing gas or hydrocarbons is interrupted, a scavenging blast of air, nitrogen or water vapour may be blown into the tuyere. In the alternative embodiment shown in Fig. 3 the inner surface of intermediate conduit 24 comprises a cylindrical portion 26 followed by a convergent section 27, a throat 28 and a divergent section 29, said conduit 24 also being provided with a ring of oblique passages 30 which open at 31 into the divergent section 29 a small distance from the throat 28 so that part of the hydrocarbon flow is atomized in the oxidizing gas stream just before it leaves the tuyere. The other conduit 32 terminates in a converging portion 35.