FLOCCULATING AND CONCENTRATING DEVICE AND METHOD

PURPOSE:To form an unflocculated fine particle and a formed floc into a giant floc in a flocculation tank by a forced violent collision and a mild collision. CONSTITUTION:A flocculation tank 7 provided in a solid-liq. separation chamber 10 has an opening expanding upward from the bottom. A mixing pipe outlet 8 is opened in the collision mixing part 20 in the tank. In this flocculation tank, the particle not flocculated in the mixing pipe is violently collided with the floc to form a small floc. Medium and large flocs are formed in the fluidized bed at the center of the flocculation tank and a giant floc in the moving bed at the upper part of the tank. The giant floc slides down on an inclined plate 23 from an overflow weir 9 and is sent into the concd. sludge in the solid-liq. separation tank in a short period. The concd. sludge is sent to an agitating and mixing tank 5 by a circulating pump 12, mixed with a dil. contaminated liq., supplied to a dispersion chamber 18 and recycled.