FLOCCULANT INJECTION DEVICE, FLOCCULANT INJECTION METHOD, AND COMPUTER PROGRAM

To set an appropriate flocculation condition for a floc with respect to water quality variation.SOLUTION: A flocculant injection device comprises: an image analysis section 8 for calculating a value representing a size of a floc and a shape value, on the basis of an image having photographed a floc in treated water at a water purification facility; a sedimentation velocity arithmetic section 10 for calculating a resistance coefficient which determines resistance being upward force applied when a floc settles, and for calculating an effective density being a difference in density between a floc and fluid in the periphery, by using the value representing the size of a floc and the shape value, and for calculating a sedimentation velocity estimation value on the basis of a balance relation between gravity force, buoyant force, and resistance force that are applied to a floc in treated water by using the resistance coefficient and the effective density; and a flocculation condition adjustment section 11 for adjusting a flocculation condition on the basis of the sedimentation velocity estimation value.SELECTED DRAWING: Figure 1 【課題】 水質変動に対する適切なフロックの凝集条件を設定する。【解決手段】 実施形態による凝集剤注入装置は、浄水施設における被処理水中のフロックを撮影した画像に基づいて、フロックの大きさを表す値と形状値とを算出する画像解析部８と、フロックの大きさを表す値と形状値とを用いて、フロックが沈降する時にかかる上向きの力である抗力を決める抵抗係数と、フロックと周囲の流体との密度差である有効密度とを演算し、抵抗係数と有効密度とを用いて被処理水中のフロックに掛かる重力と浮力と抗力との力のつり合いの関係に基づいて沈降速度推定値を演算する沈降速度演算部１０と、沈降速度推定値に基づいて凝集条件を調整する凝集条件調整部１１と、を備える。【選択図】図１