Treatment of phosphorus waste water using crystallization method

Phosphorus is the restrictive factor of water eutrophication and phosphorus removal is the key point to control this phenomenon. It's also important to recover phosphorus resource from wastewater. Crystallization method was used to treat and recycle high concentration phosphorus wastewater, the selection of organic solvent, influence of volume ratio of organic solvent and wastewater, precipitation time and stirring speed on the production of crystal and its structure was investigated. Experimental results indicate that, with ethanol as extractant, under the condition of volume ratio of ethanol to wastewater being 1.5:1 and stirring speed about 200 r/min, crystal precipitated fast with fine crystal shape and purity, phosphorus removal efficiency more than 85% was obtained.