摘要 |
A lance (24) for top submerged lancing (TSL) injection in a pyro-metallurgical operation (10), wherein the lance (24) has at least two substantially concentric pipes (28, 30), with an annular passage (42) for oxygen-containing gas defined between an outermost one of the pipes (28) and a next adjacent pipe (30) and a further passage (46) for fuel defined within an innermost one of the pipes (30); the outermost pipe (28) has a lower part of its length, from a submergible lower outlet end of the lance (24), by which the outermost pipe (28) extends beyond an outlet end of the or each other pipe (30) to define between the outlet end of the outermost pipe (28) and the outlet end of the or each other pipe (30) a chamber (34) with which the passage (42) for oxygen- containing gas communicates; and the lance (24) further includes a gas flow-modifying device (60) that is disposed in a lower end section of the passage (42) for oxygen- containing gas, adjacent to the chamber (34), and that is operable to impart an inward flow component, away from the inner surface of the outermost pipe (28), to oxygen- containing gas passing into and longitudinally within the chamber (34) towards the outlet end of the lance (24) and thereby enhance mixing of the oxygen-containing gas with fuel passing into the chamber (34) from the passage (46) for fuel. |