次氯酸钠对剑水蚤灭活动力学及紫外强化灭活

水源水体富营养化导致剑水蚤孳生，进入供水系统后威胁供水安全.为高效控制剑水蚤污染风险，通过适当增加NaClO灭活CT值（NaClO浓度与接触时间乘积）范围，系统研究了NaClO对剑水蚤灭活动力学过程，同时探讨了紫外照射对灭活效果的强化作用.结果表明：NaClO对剑水蚤的灭活动力学过程符合迟滞型两阶段准一级动力学过程，灭活反应活化能为3774J/mol；pH值对灭活动力学过程的影响，主要通过改变溶液中HOCl和ClO^-物质的量及其化学稳定性来实现.当灭活CT值超出70mg min/L时，中性条件下NaClO对剑水蚤的灭活效率最高，碱性次之，酸性最差；浊度物质会削弱NaClO对剑水蚤的灭活效果，浊度物质会迟滞NaClO从液相主体向剑水蚤体表边界层的传质过程，被剑水蚤体表吸附后也会阻碍NaClO向剑水蚤体内的渗透过程.紫外照射尽管无法实现对剑水蚤的灭活，但可以强化NaClO对剑水蚤的灭活效果，经紫外照射后，剑水蚤灭活迟滞期消失或缩短，同时灭活反应速率常数增加.当pH值为6、7和8时，紫外照射预处理后，各自灭活反应速率常数分别由0.0093、0.02185和0.0206提高至0.0105、0.02673和0.0286.

Inactivation kinetics of cyclops by sodium hypochlorite and the intensification of inactivation effects with ultraviolet irradiation

Once entering into the water supply system, Cyclops, which breed in the source water due to eutrophication, will led to the contamination of drinking water. To effectively control the risk of Cyclops, the inactivation kinetics of Cyclops by NaClO was investigated systematically by appropriately increasing the range of CT values (the product of concentration of NaClO and reaction time) during the inactivation by NaClO. Meanwhile, the intensification of inactivation effect by UV irradiation was discussed. The results showed that the inactivation kinetics of Cyclops by NaClO satisfied the two phase delayed pseudo first-order kinetics process, and the activation energy of inactivated reaction was 3774 J/mol. The influence of pH values on the inactivation kinetics process of Cyclops by NaClO was realized through the changing of both the amount and the chemical stability of HOCl and ClO^- in the solution. When CT value exceeded 70 mg×min/L, NaClO possessed the highest inactivation effectiveness under the neutral conditions, and less effectiveness under alkaline condition and the least effectiveness under acidic condition. The inactivation effectiveness of Cyclops by NaClO was decreased by the turbidity substances because of their blocking effects on the transport of NaClO from bulk liquid to the boundary layer on the surface of Cyclops. Furthermore, the turbidity substances adsorbed on the surface of Cyclops delayed the permeation process of NaClO from the surface to inside of Cyclops, and eventually reduced the inactivation effectiveness. Inactivation effectiveness of Cyclops by NaClO was enhanced by the UV irradiation, despite that the UV irradiation itself could not kill the Cyclop. After the UV irradiation, the lag phase of cyclop inactivation disappeared or decreased, and the rate constant of inactivation reaction increased. For the pH values 6, 7 and 8, after the UV irradiation, the rate constant of inactivation reaction increased from 0.0093 to 0.0105, 0.02185 to 0.02673 and 0.0206 to 0.0286, respectively.