基于絮体生长特性和体系稳定性的海水混凝过程  

Seawater coagulation process based on floc properties and stability kinetics

作　　者：赵瑾[1] 王树勋[1] 王静[1] 张雨山[1] 

机构地区：[1]国家海洋局天津海水淡化与综合利用研究所,天津300192

出　　处：《环境工程学报》2015年第6期2840-2846,共7页Chinese Journal of Environmental Engineering

基　　金：海洋公益性行业科研专项项目(201105026);中央级公益性科研院所基本科研业务费专项资金项目(K-JBYWF-2012-G07)

摘　　要：以三氯化铁和聚二甲基二烯丙基氯化铵(PDMDAAC)为主要原料,制备PFC-PDMDAAC复合絮凝剂,分析其形貌特征,考察对海水的絮凝效果,并监测絮凝过程中絮体聚集变化、动态沉降及不同温度下絮凝程度的变化规律。结果表明,PFC-PDMDAAC的长链枝杈状结构使其具有较好的除浊效果;当投加量从1×10-5mol/L增加到2×10-4mol/L,体系中絮体平均粒径从5.92μm增大至53.7μm,粒径变化速率从65.5133μm/min增加到5 385.66μm/min;絮凝指数FI受海水温度的影响很大,温度越低,FI曲线上升越缓慢;与未投絮凝剂、投加PFC相比,投加PFC-PDMDAAC的海水体系具有较大的稳定动力学参数。通过定量分析絮体平均粒径、粒径变化速率、絮凝指数FI及稳定动力学参数等,从絮体特性和体系稳定动力学角度为监测混凝过程提供参考。In this study,Fe Cl3 and PDMDAAC( poly dimethyl diallyl ammonium chloride) were used as main raw materials to prepare composite flocculants. Topography characteristics were analyzed and the effects of composite flocculants on the removal efficiency were investigated. Accumulation of flocculating constituents,dynamic settlement,and the degree of flocculation at different temperatures were supervised in flocculation process.The results showed that PFC-PDMDAAC had the better effect of removing turbidity because of the long-chain branch axils structure. When the dosage increased from 1 × 10- 5mol / L to 2 × 10- 4mol / L,the average particle size of flocs in the system increased from 5. 92 μm to 53. 7 μm. And the particle size variation rate increased from 65. 5133 μm / min to 5385. 66 μm / min. Flocculation index was greatly influenced by seawater temperature.The lower temperature,the slower FI curves rised. Compared with PFC and the situation without flocculation,seawater system had large stability kinetics parameters with PFC-PDMDAAC. By quantitative analyzing the average particle size,variation rate of particle diameter,flocculation index and stability kinetics parameters,the paper provided the reference for monitoring the flocculation process from the viewpoint of floc properties and stability kinetics.

关 键 词：混凝 海水 稳定性 温度 动力学 Turbiscan Lab iPDA 

分 类 号：X55[环境科学与工程—环境工程]