【摘要】 铝类絮凝剂对细颗粒泥沙絮凝沉降有重要作用 ,常应用于浑水澄清、农业污水处理等研究中。在AlCl3 浓度为 0～ 1 7mmol/L ,泥沙浓度为 1 0g/L时 ,用吸管法研究了AlCl3 对细颗粒泥沙絮凝沉降的影响 ,结果表明 :在液面下同一深度 ,泥沙浓度随时间呈指数衰减 ;悬液经多次搅拌后再沉降 ,其沉速减缓 ;当AlCl3 浓度为 0 9～ 1 7mmol/L时 ,出现明显的清浑水交界面 ,交界面随时间等速下降 ,平均沉速为 4 75 6cm/min ,对应的絮团平均粒径为 0 0 31 5mm ;土娄土絮凝临界粒径为 0 0 2 7mm。更多还原

【Abstract】 Aluminum flocculants have an important role in the flocculation and settling of fine sediment, and are often used to clear muddy water and treat agricultural waste water. In this paper, sediment concentration of 10 g/L is prepared in 1 000mL cylinder which contained AlCl 3 solutions with concentration ranging from 0 to 1.7mmol/L. The relative sediment concentration at the depth of 20cm below suspension surface is measured with a 20mL pipette. The results show that the sediment concentration decreases exponentially with time at the same depth below suspension surface. Effects of electrolyte on fine sediment flocculation and settling become small and the mean velocity decreases obviously after the suspension is mixed completely for several times. At the given sediment concentration, the emergence of the interface between supernatant and sediment suspension depends on the electrolyte and its concentration. When AlCl 3 concentration is higher than 0.9mmol/L, the obvious interface will appear. At the same time, the interface settles uniformly with time, and the mean particle size is 0.0315mm with the mean velocity of 4.756cm/min. The critical particle size to flocculate is 0.027mm.更多还原