The hydrodynamic filter separator for removal of urban storm runoff

The majority of storm runoff pollution is trapped in particles smaller than 100 μm in diameter. Solid particles smaller than 100 μm in diameter are not easily separated by conventional types of hydrodynamic separator, and remain in suspension in overflow. To overcome this problem, a HDFS (hydrodynamic filter separator) has been developed for treatment of the microparticles in urban storm runoff. We conducted a laboratory scale study on treatable potential of microparticles using HDFS that combined HDS with perlite filter. To determine the efficiency for various operation conditions, a series of experiments was performed with different solids concentrations and surface loading rate. The operation ranges of surface loading rates were 100 to 2,800 m³/m²/day, and influent solids concentrations were varied from 800 to 1,900 mg/L. Also, the particle size distribution was monitored to investigate the effects of surface loading rates on the particle size. Results indicated that the HDFS-Inside type showed greater efficiency at solids separation than the other type.