| 摘要 |
A method of flocculating sedimentation treatment for water to be treated, in which the amount of inorganic flocculant used in a water purification treatment system is limited farther than in the prior art and simultaneously the densification and miniaturization of remaining microflocs and flocs are realized to thereby obtaining a clear water of high quality while attaining reduction of the amount of sludge generated. The method of flocculating sedimentation treatment for water (1) to be treated comprises the microflocculation step of microflocculating microparticles suspended in water (1) to be treated in advance; the step of flocculating the microflocs; and the step of sedimentation separation for the flocs. In the method, a tilted plate (8) for flocculation of 5 to 50 mm pitch width is disposed in the final stage of the flocculation step, and the amount of used inorganic flocculant is limited so that as compared with the turbidity of the water (1) to be treated before its passing through the tilted plate (8), the turbidity after the passage is 4/5 or below thereof. |
