| 摘要 |
<p>PROBLEM TO BE SOLVED: To set a fluidizing ratio to the optimum range to enable efficient biological treatment by disposing a stirring means for controlling the amt. of organisms bonded to a carrier in a treatment tank. SOLUTION: A raw water finflow part 12, the support bed 14 of a biological membrane bonded carrier and an air diffusion means 15 are arranged on the bottom part of a treatment tank 11 and a treated water outflow part 16 is formed at the upper part of the tank 11 but, in this case, a stirring means 17 for controlling the amt. of organisms bonded to the carrier 13 is disposed in the treatment tank 11. This stirring means 17 is constituted by fixing two plate-shaped paddles to a rotary shaft 19. Since the carrier 13 rises to the upper part of the treatment tank 11 accompanied by an increase in the adhesion amt. of biological membranes, the stirring means 17 is disposed at the proper position of the treatment tank 11 to properly peel the biological membranes bonded to the carrier 13 and the carrier 13 from which biological membranes are removed is returned to the lower bed part of a fluidizied bed.</p> |
