High Effi ciency Air Diffuser for Wastewater Treatment

Performances of a metallic air diffuser with original slit orifi ce (JFE FINEBUBBLER) were investigated. Oxygen transfer effi ciency was higher than 30％ by the air diffuser with pressure loss of below 200 mm-aq. This device could contribute the reduction of energy consumption compared with conventional apparatused. In addition, the following two methods against blockage problems were confi rmed to be effective to maintain the initial performance of the air diffuser when applied for real sewage aeration; (1) application of daily water-blow system to suppress increase of annual pressure-loss; (2) application of chemical washing treatment to recover performances completely to its initial level in case of a long-term increase of pressure-loss at the diffuser.