Normandie UNIV, UNIHAVRE, UMR 6294, CNRS, LOMC, 76600 Le Havre, France.
Normandie UNIV, UNIHAVRE, UMR 6294, CNRS, LOMC, 76600 Le Havre, France.
Sci Total Environ. 2017 Oct 15;596-597:222-229. doi: 10.1016/j.scitotenv.2017.03.254. Epub 2017 Apr 20.
In this paper, numerical simulations of experimental data were performed with kinetic rate coefficients to characterize the retention and re-entrainment dynamics under different hydrodynamic conditions for monodisperse and polydisperse latex particles (3, 10, 16μm and the mixture). The results show that drastic increase in fluid velocity provokes hardly any remarkable decrease in retention in the presence of large energy barriers (>2000kT). Systematical increases in deposition and re-entrainment dynamic rates were observed with fluid velocity and/or particle size. Increased irreversible deposition rate indicates straining and wedging dominate deposition in this study. Excess retention of 3μm particle in the polydisperse particle suspension was observed. The origins are reckoned that deposited larger particles may hinder the re-entrainment of smaller particles near the grain-to-grain contact and can provide additional sites of attachment.
本文针对单分散和多分散乳胶颗粒（3、10、16μm 以及混合物），通过动力学速率系数对实验数据进行数值模拟，以描述在不同水动力条件下的滞留和再悬浮动力学。结果表明，在存在大能量势垒（>2000kT）的情况下，流体速度的急剧增加几乎不会导致滞留率显著降低。随着流体速度和/或颗粒尺寸的增加，沉积和再悬浮动力学速率呈系统增加。不可逆沉积速率的增加表明在本研究中，应变和楔入主导着沉积。在多分散颗粒悬浮液中观察到 3μm 颗粒的过量滞留。据推测，沉积的较大颗粒可能会阻碍颗粒间接触处附近较小颗粒的再悬浮，并且可以提供额外的附着位点。
