Menetelmä ja järjestelmä fluoridin poistamiseksi sulfaattiliuoksista

摘要

The invention relates to a method and an arrangement for removing fluoride and fluorine components from zinc containing process liquors and slurries. The method comprises the steps of i) withdrawing a flow of zinc sulfate containing process liquor or slurry from a zinc recovery process (12); ii) contacting the flow of zinc sulfate containing process liquor or slurry with a clay sorbent (3, 6) capable of sorbing fluoride or fluorine containing components present in the zinc sulfate containing process liquor or slurry to obtain a mixture of a clay sorbent comprising immobilized fluoride and a zinc sulfate containing process liquor or slurry at least partly depleted of fluoride; ii) separating the clay sorbent comprising immobilized fluoride from the mixture to obtain a treated zinc solution (10); and iv) returning the zinc solution back to the zinc recovery process (12).