Study On The Treatment Of Ammonia-Nitrogenous Wastewater In Ta/Nb Metallurgy

This article introduces a technique how to reduce the concentration of SO42- F- NH4+ in waste water from Ta/Nb metallurgy and recover ammonia or ammonium salts . Reviewing the sorts of wastewater from the process implies that it is necessary and possible to treat different kinds of water with different methods. Neutralizing strong acid wastewater by CaO could remove the SO/ , F~ from wastewater satisfactorily. Meanwhile, the basic wastewater with small concentration of SO42-, F-, NH4+ was disposed by CaO precipitation distillation biological treatment method , which could reduce the concentration of NH4+ of the drained wastewater lower than 25mg/l and up to the standard draining wastewater . The wastewater with high concentration of SO42-, F-, NH4+ is disposed by evaporation-recrystallization, thermal decomposition in which the condensation of NH3 H2O NH4HSO4 NH4HF2 were recovered and reused in Ta/Nb metallurgy economically.