| 摘要 |
<p>PURPOSE:To prevent the occurrence of slagging phenomena and peel excess micro- organisms efficiently over the entire area of a fluidized bed by circulatively supplying peeling particles for peeling the micro-organisms on the fluidized bed of the carriers stuck with micro-organisms. CONSTITUTION:The water to be treated introduced into a vessel 1 is treated biologically by the micro-organisms stuck on the surfaces of carriers in the process of ascending in a fluidized bed 4, thence it is derived to the outside of the system from a treated water pipe 6 via a particle recovering part 5. In this state, the peeling particles in a particle storage tank 8 are supplied at a constant rate into an inflow pipe 2 for the water to be treated through a particle supply pipe 10 by a particle supply device 9. While being mixed with the water to be treated, the particles are conducted to the lower part of the vessel 1 and ascend in the bed 4. Since the specific gravities of the particles 11 are smaller than those of the carriers, the speed at which they pass the inside of the bed 4 is high and they collide against the carriers at more than a constant speed, so that the excess micro-organisms stuck on the carriers are peeled effectively.</p> |
