Patent ID: 6383373
Filing Date: 2002-05-07
Classification: C02F,Y02W,Y10S

Abstract:
A biological filtration apparatus comprising:a raw water introducing section for introducing raw water as water to be processed; a biological filtration section, disposed on the lower side of said raw water introducing section, for biologically purifying/refining/filtrating said raw water so as to yield processed water; a support section, disposed on the lower side of said biological filtration section, for supporting said biological filtration section, said support section having a liquid and gas permeability; and a water collecting section, disposed on the lower side of said support section, for collecting said processed water; said biological filtration section includes a packed bed comprising a hollow carrier particle, made of a resin, having a true specific gravity of at least 1.01 g/ml but less than 1.2 g/ml; and said support section comprises a planar member and a water collecting nozzle which is arranged in said planar member and by which the biological filtration section communicates with the water collecting section; said water collecting nozzle having a lower part formed with a water outlet/inlet for discharging said processed water and for receiving backwashing water and an air inlet for receiving diffusing and/or backwashing air.