ABSTRACT
As the wolframite resource depletion, scheelite has gained more and more focus. The study on decomposition of scheelite concentrate leaching become more and more, and many are reported, such as Hydrochloric acid decomposition method and nitric acid decomposition method, the soda sintering method, the soda pressure cooking method, alkali decomposition method, the thermodynamics ball-milling method, the fluoride decomposition method, the chlorination process method. Because of the Ksp Ca10(PO4)6(OH)2<K sp Ca3(PO4)2<K sp CaCO3<K sp Ca(OH)2, the phosphate as leaching agent already be concerned. The scheelite invariable system closed cycle of smelting process replace the continuation of one hundred new train of thought of the transformation of the process, The main process is ammonium phosphate digestion of scheelite under the condition of low concentration of alkali, one step to obtain ammonium tungstate solution, after purification, evaporation crystallization and so on, we can get high purity APT. In this thesis, we study on low alkali environment, the dynamics factors affecting of decomposition of ammonium phosphate scheelite.
