文档介绍：pH值对高铁酸盐复合药剂强化除藻的影响
(作者:___________单位: ___________邮编: ___________)
摘要:探讨了pH值对高铁酸盐复合药剂强化混凝除藻效果的影响规律,、。试验结果表明,对于微酸性原水(pH=),高铁酸盐复合药剂强化混凝除藻效果最好;随着pH值的提高,高铁酸盐复合药剂强化混凝除藻效果逐渐降低,但即使在较高pH值条件下(pH=)仍然可取得明显的强化除藻效果。
关键词:李圭白除藻高铁酸盐复合药剂 pH值
Effect of pH Values on Enhanced Algae Removal by Pre-Oxidation posite Ferrate Chemicals
Abstract: The effect of pH on the removal of algae by pre oxidation with posite chemical containing ferrate was investigated by jar tests. The results showed that the pre oxidation greatly enhanced the algae remo val with much reduction of residual algae in both settled and filtered water. It was found that ma ximum removal of algae was achieved at lower pH value of raw water(pH=5) and the n the removal efficiency decrease with increase of pH value. However, it was also found that thedistinctly enhanced algae removal could be achieved even at higher pH value(pH=)
Keywords: algae removal; composite ferrate chemicals; pH
大多数湖泊、水库、河川属于中碱性水体。由于一般淡水水体中碳酸系统的缓冲作用,pH值多在6~9之间变化,有时受浮游藻类强烈光合作用的影响,在午后一段时间随着CO2的消耗,水体的pH值升高;半夜以后,光合作用停止,CO2量在水体中增高,pH值降到最低。但是,如果湖泊、水库发生了水华现象,在强烈的光合作用下,大量的CO2被耗尽,可使pH值急剧升高达到9~10,~。另外藻类形成的浊度,其组成大多为有机质,电动电位(ζ)约在-40mV以上,具有较高的稳定性,比重小,难于下沉,且藻类自身常粘附在滤料表面,使过滤周期缩短。尽管能够影响混凝效果的因素很多,但混凝过程中的pH是首要因素,因为pH值直接影响水中胶体浊质和藻类的电荷,控制水中化学反应动力学。同时pH决定混凝剂的水解速率和混凝剂水解产物的类型、浓度和电荷,控制金属氢氧化物沉淀