本研究以實驗分析攪拌混凝槽內最大膠羽粒徑之變化，多數實驗在3.86升之標準攪拌槽配備 6 片直葉盤式或 45 °斜漿式等兩型攪拌翼進行。實驗結果顯示，10 ～ 20 秒之快混時間即形成最大膠羽，隨槽內平均剪應率與混凝化學條件等之改變，不同型式攪拌翼對膠羽成長之影響有明顯差異。本文亦提出可藉由懸浮液獨度偵測來線上控制攪拌翼轉速，以獲致較佳之膠羽成長路徑。本研究也提出一理論模式，以關聯最大穩定膠羽粒徑與膠羽強度和攪拌翼轉速，經與文獻中強度均一之膠羽的碎裂結果相比較，此模式之適用性獲得驗証。依據此模式與最大穩定膠羽之實驗結果，本文亦探討了經長時間攪拌作用後之膠羽強度與攪拌翼轉速之關係。

　　　　　Variations of the maximum floc size in the rapid-mixing stages ofcoagulation and flocculation were analyzed to investigate the effects of averageshear rate and type of impeller on floc growth in mixing tanks. Most of theexperiments were carried out in a 3.86 liter standard tank with two differentimpellers: a six-bladed Rushton disk turbine and a 45 ° pitched-bladed turbine.Detailed floc size measurements indicated that only 10 ～ 20s of rapid mixing isrequired and that the differences in performance between the two impellersdepend on the average shear rate and the chemical conditions applied. It wassuggested that on-line measurement of turbidity can be used to control theimpeller speeds for achieving more favorable floc growth.A theoretical model for relating the maximum size of stable flocs to theimpeller speed and floc strength was also presented. Positive correlation hasbeen obtained between this model and the experimental results in literatureunder a condition of constant adhesive force of flocs. Based on the model andthe floc size measurements, the dependence of the adhesive force of flocs aftera long period of stirring on the impeller speed was also discussed.