| 摘要 |
<p>PURPOSE:To attain to enlarge a rotary disc while a biological membrane grown on a rotary disc is prevented from being peeled off by circulating the water to be treated in a water tank to control the relative speed of a rotary disk and the water to be treated. CONSTITUTION:A water tank 1 is divided into an upper and a lower portion by a partition wall 2 and a rotor 4 is arranged so as to be contacted with an upper surface of the partition wall 2. When raw water is introduced from a pipe, said raw water is circulated to a direction of A, B and C and exhausted from an outlet H and the precipitate 8 is taken out from a pipe 7. The rotor 4 is rotated to a direction of an arrow by a motor 15 and the rotating direction thereof in water is coincident with the flow direction of the circulated water and the peripheral speed of the rotor in water is lowered relatively. Then, even if the rotating speed is increased, the biological membrane on the rotor is prevented from being peeled off and, as a result, the diameter of the rotor can be enlarged.</p> |
