Top Submerged Lance Slag Fuming

As an alternative to the conventional slag fuming furnace, a top submerged lance slag bath reactor may be used for zinc fuming. In this process fuel as gas, oil or pulverised coal is injected with oxygen 

Top-submerged lancing (TSL) - slag bath reactor operating principles and construction 

Zinc is fumed from molten slag as metal vapour and is oxidised to ZnO fume above the bath by secondary air. Considerable heat is generated by secondary combustion, and can be partly captured by the bath as molten slag is projected into the gas space by the turbulence generated by the lance. This heat capture by the bath reduces the actual fuel needs within the bath and improves fuel efficiency. 

10 - Metallic iron and zinc content of slags versus reducing conditions (Sekiguchi and Azuma, 1998). 

These questions of containment and refractory life are the primary concerns in the application of this process and are still in an evolutionary phase at the time of writing. Otherwise the approach has the advantage of relative simplicity. 

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