An Overview of Flashing Phenomena in Pressure Hydrometallurgy

Pressure hydrometallurgy has attracted much attention for its characteristics, such as the high adaptability of raw materials and environmental friendliness. Flashing (flash boiling or flash evaporation) refers to phase change phenomenon from liquid gas triggered by depressurization, which is an important connection between high-pressure processes atmospheric ones in pressure hydrometallurgy. This paper takes flashing process zinc leaching alumina Bayer examples, describes detail first time, shows importance energy recovery, solution concentration, balance, well increasing equipment life. According solid holdup (the volume percentage solid), this proposes divide into (low holdup) slurry (high holdup). A further focus put on reviewing state art related studies. The results reveal that research scarce often oversimplified, e.g., ignoring BPE (boiling point elevation) NEA (non-equilibrium allowance) effect particles flashing. Computational fluid dynamic (CFD) simulation a promising tool investigating process. Based progress made other fields, seawater desalination, nuclear safety analysis, engine fuel atomization, we suggest can be studied using CFD–PBM (population balance model) coupled two-fluid model, since wide size range bubbles will generated. For flashing, bubble nucleation rate mechanism dynamics should accounted additionally, quantitative description still lacking. Meanwhile, data validating numerical method are because harsh experimental conditions, needed. In summary, work presents overview some guidelines future