| 摘要 |
<p>A process for the manufacture of substantially pure Zirconium Oxide powder from zirconium-bearing materials, comprising the following steps: a) a solution, containing 30-40 % CaCl2 by weight, is homogeneously mixed with ground Zirconium-bearing materials in a mole ratio of ZrSiO4:CaCl2 in the range of 0.9-1.3. b) The slurry is granulated and dried in contact with hot gases to obtain granules of 0.1 to 10 mm size, with a residual water content less than 6 %. c) The dried granules are continuously fed to a first kiln, where they are contacted counter-currently with hot combustion gases containing water vapors, and heated gradually to 900-1000° C. d) The intermediate solids from the first kiln are continuously transferred into a second kiln and heated to 1,400° C. The remaining traces of HCI are removed and the solid phases are reorganized into ZrO2 and CaO, SiO2.</p> |
