School of Environmental Science and Engineering, Shandong University, No. 27, Shanda South Road, Jinan 250100, Shandong, PR China.
Bioresour Technol. 2012 Jun;113:89-96. doi: 10.1016/j.biortech.2011.11.029. Epub 2011 Nov 22.
The compound bioflocculant (CBF)-aluminum sulfate (AS) dual-coagulant and AS were comparatively studied for the coagulation of kaolin-humic acid solution. Floc properties including floc growth rate, size, strength, recoverability and fractal dimension under different pH conditions were investigated by Mastersizer 2000. Results indicated that, the flocs formed by AS-CBF (AS dosed first) showed the largest size and the best recoverability across the pH range investigated. While flocs formed by CBF-AS gave the most compact structure. The three coagulants exhibited similar floc growth rate and strength. Moreover, flocs formed in acidic conditions were stronger and more recoverable but showed lower growth rate, smaller size and looser structure compared to those formed at pH>6 regardless of the coagulant used. Charge neutralization was the dominant mechanism for AS at low pH, while the coagulation mechanism transformed to enmeshment as the pH increased. There was an additional adsorption bridging effect for AS-CBF and CBF-AS.
复合生物絮凝剂（CBF）-硫酸铝（AS）双混凝剂和 AS 被比较研究用于高岭土-腐殖酸溶液的混凝。通过 Mastersizer 2000 研究了不同 pH 值条件下的絮体特性，包括絮体生长速率、大小、强度、可恢复性和分形维数。结果表明，在研究的 pH 值范围内，AS-CBF（先加 AS）形成的絮体具有最大的尺寸和最好的可恢复性。而 CBF-AS 形成的絮体结构最紧凑。三种混凝剂表现出相似的絮体生长速率和强度。此外，与在 pH>6 时形成的絮体相比，无论使用哪种混凝剂，在酸性条件下形成的絮体强度更高、可恢复性更好，但生长速率更低、尺寸更小、结构更松散。在低 pH 值下，AS 的主要混凝机制是电荷中和，而随着 pH 值的升高，混凝机制转变为网捕。AS-CBF 和 CBF-AS 还有额外的吸附架桥作用。
