earticle

영어

Higher concentrations of MLSS(Mixed Liquor Suspended Solis) in BNR(Biological Nut-rient Removal) systems and stringent effluent suspended solid concentration requirements demand a good design practice for secondary clarifiers. Although SOR(Surface Overflow Rate) and SLR(surface Loading Rate) are commonly used in secondary clarifier design, these parameters do not reflect hydraulics and solid-liquid separation within clarifiers. In this paper, the Clari-2D model that can simulate hydraulic and MLSS settling behaviors was used to evaluate secondary clarifier design in P water reclamation plant in Gyeonggi province, S. KOREA. Three parameters in settling equation were experimentally defined : Vmax is 14.718 m/hr, K1 is 0.242 m3/kg and K2 is 20 m3/kg, respectively. Steady and dynamic state simulations were carried out to find a diurnal inflow effect on clarifier. Also, effects of chemical addition to enhance phosphorus removal were simulated. With chemical addition, the hourly maximum effluent SS(suspended solid) concentration was found 8.8 mg/L. This concentration meets the SS effluent requirement that is 10 mg/L.