Process for Producing Caco3 or Mgco3

摘要

The present invention relates to a process for producing CaCO3 or MgCO3 from a feedstock comprising a Ca- or Mg-comprising mixed metal oxide, wherein: (a) an aqueous slurry of the feedstock is contacted with a C02 containing gas to form an aqueous solution of Ca(HCO3)2 or Mg(HCO3)2 and a solid Ca- or Mg-depleted feedstock; (b) part or all of the aqueous solution of Ca(HCO3)2 or Mg(HCO3)2 is separated from the solid Ca- or Mg-depleted feedstock; (c) CaCO3 or MgCO3 is precipitated from the separated aqueous solution of Ca(HCO3)2 or Mg(HCO3)2; and (d) the precipitated CaCO3 or MgCO3 is recovered as product. The invention further relates to a process for the production of an aqueous solution of Ca(HCO3)2 or Mg(HCO3)2.