Desulphurisation of molten iron and steel - by blowing dosed amount of magnesium vapour into the melt

摘要

In the desulphurisation of crude iron and steel melts by adding Mg or similar materials, the addn., pref. Mg is converted to the gaseous state outside the treatment vessel and then a dosed amt. is blown at a controlled speed into themelt. The gas-forming chamber and the feed pipes are pref. rendered inert using argon, esp. preheated argon which can be used to heat both the chamber and the feed pipes, and also to prevent the molten metal from penetrating into the lance used to feed the Mg vapour into the bath. The pressure of the Mg vapour is pref. min. 0.5 atmos above the ferrostatic pressure in the bath, and the pref. devices are included in the claims. Precise control of desulphurisation and the avoidance of molten spray from the vessel is achieved.