纳米SiO2的分散表征及其强化混凝低温低浊水研究

采用原子力显微镜、激光粒度仪对超声分散纳米SiO2的粒径分布、微观形状等进行了表征，并使用该纳米分散液对低温、低浊水进行了强化混凝研究。结果表明：纳米SiO2可均匀、稳定地分散在水溶液中，平均粒径为30nm，形状呈球形，在pH值为3～12时其表面带负电；将其用于强化混凝处理低温、低浊水时可以显著降低出水浊度，提高所形成矾花的密实程度，同时改善矾花的沉降性能。

Dispersion and Characteristic of SiO2 Nanoparticles and Study on Enhanced Coagulation of Low Temperature and Turbidity Water

The size distribution,morphology,and surface charge property of the ultrasonic dispersed SiO_2 nanoparticles were characterized by the atomic force microscopy(AFM) and the photon correlation spectroscopy (PCS) size measurements.The enhanced coagulation of low temperature and low turbidity water was carried out using the nano-dispersed liquid.Results indicate that the SiO_2 nanoparticles can be dispersed equally and steadily in an aqueous solution,the average diameter of the SiO_2 nanoparticle is 30 nm,the surface charge property is negative at the pH value ranged from 3 to 12.When used for enhanced coagulation of low temperature and low turbidity water,the SiO_2 nanoparticles can improve the removal of the turbidity of the tested water,increase the compactness rate and sedimentation capability of flocs.