聚合氯化铁絮凝处理低温低浊水的研究

Study on the flocculation of low temperature and low turbidity water by polyferric chloride

通过聚合氯化铁(PFC)对高岭土悬浮颗粒的絮凝试验中浊度和Zeta电位的测试,发现低温时在相同的PFC投药量下随着碱化度(B)的增大,Zeta电位减小;在达到相同的浊度去除,低温时PFC的投加量要小于常温时,在相同的药剂投加量低温时Zeta电位要高于常温时;温度降低PFC水解和沉淀速度减小,使得PFC水解中间体更易与污染物反应,同时增强了电中和能力,减少了PFC的用量;温度的降低使得PFC的多核羟基络合物中间体水解程度减小而保持形态的时间延长,所以PFC比传统混凝剂FeCl3处理低温低浊水更有效。

The turbidity and Zeta potential were analyzed by flocculation kaolin with polyferric chloride(PFC). The experimental results showed that the Zeta potential decreases with the increase of B under the same dose of PFC at low temperature The dose of PFC at low temperature is less than at normal temperature when the same removal efficiency of turbidity. A diminished rate of hydrolysis and precipitation means that cationic intermediate species are more available for interaction with contaminants. Low temperature enhances the charge neutralizing ability of hydrolyzing metal coagulants and necessitate a reduction in dose. The fact that the effectiveness of preformed metal polymers improves with decreasing temperature may also be accounted for by a prolonged duration of polymeric species at low temperature. Therefore, PFC is more effective than FeCl 3 when the low temperature and low turbidity water are treated.