Fluoride removal in a fixed bed packed with granular calcite

  title={Fluoride removal in a fixed bed packed with granular calcite},
  author={Min Yang and T. Hashimoto and N. Hoshi and H. Myoga},
  journal={Water Research},
A fixed bed reactor filled with calcite particles (mean strokes diameter, 0.20 mm) was constructed and the reactor was used to treat synthetic wastewater containing HF, NaF, NH4F or Na2SiF6 under various conditions. Calcium ions (Ca2+) were found to exist in the treated effluent and the molar Ca2+ concentration ([Ca2+]) was related to the molar ratio of H+ to F- ([H+](0)/[F-](0)) in influent as log(10)[Ca2+] = 0.020[H+](0)/[F-](0)-4.24. The effluent F- concentration was determined by the… Expand

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