Ballasted flocculation processes were studied at laboratory scale to establish new models for assessing: (a) the mechanisms by which ballasting agent is incorporated into the floc matrix and (b) the settling velocity behavior of ballasted flocs. Ballasted flocs were found to be formed by a mechanism in which the ballasting agent is incorporated into the floc matrix by differential momentum, and the ballasting agent taking the place of the bound water content. Floc density and floc settling velocity were found to be a linear function of the ballasting agent dose. A floc density-mirosand dose relationship was suggested for simplifying a general settling velocity equation. The relationship was in the form of: &rgr;s = k1M + k2. A fractal model was also proposed for modeling the settling velocity of ballasted flocs represented by: nS=f1M+f2 dfwhere k1, k2, f1, and f 2 were coefficients that depended on floc chemical characteristics and ballasting agent dose, and the exponent f had a value of 0.45.; Results obtained from this research provided a better understanding of the ballasted flocculation process and a basis for improving existing ballasted flocculation process designs.
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机译:在实验室规模下对压载絮凝过程进行了研究,以建立评估新模型:(a)将压载剂掺入絮凝基质的机理以及(b)压载絮凝物的沉降速度行为。发现压载絮凝物是由一种机理形成的,在该机理中,通过不同的动量将压载剂掺入絮体基质中,并且压载剂代替了结合水含量。发现絮凝密度和絮凝沉降速度是压载剂剂量的线性函数。为了简化一般的沉降速度方程,建议使用絮状密度与微粉和剂量的关系。该关系的形式为:&rgr; s sub> = k italic> 1 sub> M italic> + k 斜体> 2 sub>。还提出了分形模型来模拟压载絮凝物的沉降速度,其表示为: n g> S inf> = f 1 inf> M + f 2 inf> 展开▼