Chemical Effects in Aggregation Processes in a Quiescent, Continuous Flow, Aqueous Environment

CTS-9814113，斯坦福大学的James O.Leckie使用具有光学测量颗粒大小和速度能力的静态、连续流动的流体柱，在实验室中实验模拟了天然水体中污染物的聚集过程。在延长的时间间隔内测量各种粒度分布和水化学特征的颗粒沉降率和聚集率。实验将用0.3-4微米的二氧化硅小球和二氧化钛包覆的二氧化硅小球，在不同的浓度，不同的配体和电解液的影响下，在不同的pH值下进行。用经典理论(DLVO)和表面络合的三层模型对Smoluchowski方程进行了数值求解，并计算了碰撞效率。拟议的研究与污染物在污染场地中的迁移和去向以及修复方法和水处理工艺的发展有关。

CTS-9814113James O. Leckie, Stanford UniversityThe aggregation processes of contaminants in natural waters are experimentally simulated in laboratory using a quiescent, continuous flow, fluid column with optical measuring capabilities for particle size and velocity. Particle settling rates and aggregation are measured over extended time intervals for various particle size distributions and water chemical characteristics. The experiments will be carried out with silica spheres and titania coated silica spheres of 0.3 to 4 microns, at various concentrations, under the effect of various ligants and electrolites and at different pH values. Numerical solution of the Smoluchowski's equation and the calculation of the collision efficiency using classical theory (DLVO) and the triple layer model for surface complexation. The proposed studies have relevance to transport and fate of contaminants in polluted sites, as well as to development of remediation methods and water treatment processes.