FLOCCULATION METHOD

• Main Author: OCHIAI TOSHIAKI
• Format: Patent
• Language: English; Japanese
• Published: 30.07.2015
• Subjects: PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a flocculation method which sets the turbidity at a predetermined level or less with the minimum injection amount of flocculant and permits quick correspondence with respect to an increase of suspension particles or the turbidity in water to be treated.SOLUTION: In a flocculation method, the number per unit volume of suspension particles of 0.5 to 1 μm diameter in an area of front and rear regions passing through a rapid agitation tank 2 or the turbidity is measured, on the other hand, an injection amount of necessary flocculant for providing a prescribed level of turbidity in a sand filtration basin 5 is set to the minimum limit, the number per unit volume in such a case or the maximum value of the turbidity is measured and, on the treatment stage, when a measurement value at the same position as a preliminary experiment exceeds the maximum value with respect to the number per unit volume or the turbidity, further additional injection of flocculation, and/or agitation intensity, and/or an increase of agitation time is performed until the measurement value returns to the maximum value. 【課題】最小限の凝集剤の注入量によって濁度を所定レベル以下に設定し、かつ被処理水における懸濁粒子又は濁度の増加に対し、速やかな対処を可能とする凝集処理方法を提供すること。【解決手段】急速攪拌槽２を通過する前後の領域における０．５〜１μｍ径の懸濁粒子の単位体積当りの数、又は濁度を測定する一方、事前の実験によって、砂ろ過池５における所定レベルの濁度を実現するために必要な凝集剤の注入量を最小限度に設定し、かつその場合の上記単位体積当りの数、又は濁度の最大値を測定したうえで、処理段階にて、上記単位体積当りの数又は濁度につき、前記事前の実験と同一位置における測定値が上記最大値を超えた場合に、上記測定値が上記最大値に戻るまで凝集剤の更なる追加注入及び／又は攪拌強度並びに／若しくは攪拌時間の増加を行うことによって、上記課題を達成する凝集処理方法。【選択図】図４