Abstract
Biological phosphorus removal process have still some problems from viewpoint of stable performance and reuse of phosphorus of wastewater as limited sources. The authors propose that the crystallization process can be of appropriate phosphorus removal from return sludge. Also it is shown that the process is capable of reusing phosphorus of wastewater. In this study, the newly developed crystallization process was applied to high concentration of phosphorus in thickener effluent and phosphorus stripping process. The equipment of phosphorus recovery process is up-flow fluidized-bed reactor. The experimental results proved that the removal efficiency of phosphorus (efficiency of crystallization) 75%-80% can be obtained with adjusting appropriate pH value to control coagulation. It is shown that the crystallization is not almost affected by alkalinity ranging from 150mg/l to 500mg/l.
