Aeration device and membrane filtration unit applied when collecting filtrate of solid-liquid mixed processing liquid

摘要

PPROBLEM TO BE SOLVED: To provide an air diffuser cleaning method when collecting liquid filtrate of a solid-liquid mixed treatment liquid capable of cleaning an air diffusion pipe at arbitrary timing without stopping the water discharging treatment. PSOLUTION: The air diffuser (15) comprises an air main pipe (18) connected to at least one aeration blower (B), a liquid feed pipe to be merged to the middle of the air main pipe (18), a branched conduit (25) horizontally connected via a gas feed pipe (16) branched from the air main pipe (18), and a plurality of air diffusion pipes (17) arranged orthogonally to the branched conduit (25) and horizontally, and having a plurality of air diffusion holes opened downward in a substantially vertical direction. The gas flow rate in the gas distribution pipe is set to 5 m/sec, and the liquid feed is set to 0.03 L/min/mmSP2/SP, respectively. Solid sludge caused by the gas-liquid mixed fluid and deposited to close the air diffusion holes of the air diffusion pipes (17) is efficiently removed. PCOPYRIGHT: (C)2007,JPO&INPIT