Using cheap river sands as packing material and applying ozone non- continuous aeration

Mn2+ in raw water was oxidized into insoluble compounds that attached to sand surface and formed activated membrane having ability to remove manganese.The activated membrane became mature within only five days under the experimental conditions: ozone aeration four times a day

10 min each time at 50ml·min-1.The concentration of Mn2+ in effluent could be lower than 0.1 mg·L-1.The maturity period of the filter for manganese removal was significantly reduced.The optimum operation condition for the mature filter was also explored.The results indicated that the filter surface membrane could maintain efficiency for a long time at the following conditions: manganese concentration in raw water 1.5 mg·L-1

pH higher than 7.0

dissolved oxygen concentration more than 6.5 mg·L-1 and water flow rate less than 0.6 m·h-1.