State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, Hei Longjiang, China.
J Hazard Mater. 2010 May 15;177(1-3):336-43. doi: 10.1016/j.jhazmat.2009.12.037. Epub 2009 Dec 29.
Algae in surface water have been a long-term issue all over the world, due to their adverse influence on drinking water treatment process as well as drinking water quality. The algae removal by electro-coagulation-flotation (ECF) technology was investigated in this paper. The results indicated that aluminum was an excellent electrode material for algae removal as compared with iron. The optimal parameters determined were: current density=1 mA/cm(2), pH=4-7, water temperature=18-36 degrees C, algae density=0.55 x 10(9)-1.55 x 10(9) cells/L. Under the optimal conditions, 100% of algae removal was achieved with the energy consumption as low as 0.4 kWh/m(3). The ECF performed well in acid and neutral conditions. At low initial pH of 4-7, the cell density of algae was effectively removed in the ECF, mainly through the charge neutralization mechanism; while the algae removal worsened when the pH increased (7-10), and the main mechanism shifted to sweeping flocculation and enmeshment. The mechanisms for algae removal at different pH were also confirmed by atomic force microscopy (AFM) analysis. Furthermore, initial cell density and water temperature could also influence the algae removal. Overall, the results indicated that the ECF technology was effective for algae removal, from both the technical and economical points of view.
水中藻类一直是全世界的一个长期问题，因为它们会对饮用水处理过程和饮用水质量产生不利影响。本文研究了电凝聚浮选（ECF）技术对藻类的去除效果。结果表明，与铁相比，铝是一种去除藻类的优良电极材料。确定的最佳参数为：电流密度=1 mA/cm(2)，pH 值=4-7，水温=18-36°C，藻类密度=0.55 x 10(9)-1.55 x 10(9)个细胞/L。在最佳条件下，能耗低至 0.4 kWh/m(3)时，藻类去除率达到 100%。ECF 在酸性和中性条件下表现良好。在初始 pH 值为 4-7 的低 pH 值下，ECF 有效地去除了藻类的细胞密度，主要通过电荷中和机制；而当 pH 值增加（7-10）时，藻类去除效果恶化，主要机制转变为扫流絮凝和网捕。原子力显微镜（AFM）分析也证实了不同 pH 值下藻类去除的机理。此外，初始细胞密度和水温也会影响藻类的去除。总的来说，结果表明，从技术和经济角度来看，ECF 技术对藻类的去除是有效的。
