Recovery of valuables from flue dust fines

This paper describes the results obtained during an investigation into the recovery of nickel from flue dust fines generated on a stainless steel plant. It is shown that the nickel present in this dust is mainly in the metallic form. Accordingly, gravity separation and magnetic separation techniques can be used to recover the nickel from these fines. Nickel recoveries of up to 40% were obtained by gravity separation and up to 50% by magnetic separation, at an acceptable grade. Much potential exists in applying this technique on a commercial scale, although a more extensive pilot scale test program should be performed prior to commercialisation. Variations in the nickel content of the slurry feed during large scale pilot plant tests should be counteracted by a proper sample taking program to ensure that reliable mass balances are obtained.