Institut für Mechanische Verfahrenstechnik, Strasse am Forum 8, D-76128 Karlsruhe, Germany.
J Colloid Interface Sci. 2010 Sep 1;349(1):186-95. doi: 10.1016/j.jcis.2010.05.025. Epub 2010 May 16.
Cake filtration is a widely used solid-liquid separation process. However, the high flow resistance of the nanoporous filter cake lowers the efficiency of the process significantly. The structure and thus the permeability of the filter cakes depend on the compressive load acting on the particles, the particles size, and the agglomeration of the particles. The latter is determined by the particle charge and the ionic strength of the suspension, as described by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. In this paper, we propose a combined stochastic rotation dynamics (SRD) and molecular dynamics (MD) methodology to simulate the cake formation. The simulations give further insight into the dependency of the filter cakes' structure on the agglomeration of the particles, which cannot be accessed experimentally. The permeability, as investigated with lattice Boltzmann (LB) simulations of flow through the discretized cake, depends on the particle size and porosity, and thus on the agglomeration of the particles. Our results agree qualitatively with experimental data obtained from colloidal boehmite suspensions.
过滤饼过滤是一种广泛应用的固液分离过程。然而，纳米多孔过滤饼的高流动阻力会显著降低该过程的效率。过滤饼的结构，从而也包括其渗透性，取决于作用于颗粒上的压缩载荷、颗粒大小以及颗粒的团聚。后者由颗粒电荷和悬浮液的离子强度决定，这由 Derjaguin-Landau-Verwey-Overbeek (DLVO) 理论描述。在本文中，我们提出了一种组合随机旋转动力学 (SRD) 和分子动力学 (MD) 方法来模拟滤饼的形成。这些模拟进一步深入了解了过滤饼结构对颗粒团聚的依赖性，这在实验中是无法获得的。通过对离散化滤饼内流动的格子玻尔兹曼 (LB) 模拟研究了渗透性，它取决于颗粒大小和孔隙率，因此也取决于颗粒的团聚。我们的结果与从胶体勃姆石悬浮液获得的实验数据定性一致。
