Forskningsartikel2014Vetenskapligt granskad
Stochastic collision and aggregation analysis of kaolinite in water through experiments and the spheropolygon theory
Tang, Fiona H. M.; Alonso-Marroquin, Fernando; Maggi, Federico
Sammanfattning
An approach based on spheropolygons (i.e., the Minkowski sum of a polygon with N vertices and a disk with spheroradius r) is presented to describe the shape of kaolinite aggregates in water and to investigate interparticle collision dynamics. Spheropolygons generated against images of kaolinite aggregates achieved an error between 0.5% and 20% as compared to at least 32% of equivalent spheres. These spheropolygons were used to investigate the probability of collision (Pr[C]) and aggregation (PrIA1) under the action of gravitational, viscous, contact (visco-elastic), electrostatic and van der Waals forces. In ortho-axial (i.e., frontal) collision, Pr[Al of equivalent spheres was always 1, however, stochastic analysis of collision among spheropolygons showed that PIA] decreased asymptotically with N increasing, and decreased further in pen-axial (i.e., tangential) collision. Trajectory analysis showed that not all collisions occurring within the attraction zone of the double layer resulted in aggregation, neither all those occurring outside it led to relative departure. Rather, the relative motion on surface asperities affected the intensity of contact and attractive forces to an extent to substantially control a collision outcome in either instances. Spheropolygons revealed therefore how external shape can influence particle aggregation, and suggested that this is equally important to contact and double layer forces in determining the probability of particle aggregation. (C) 2014 Elsevier Ltd. All rights reserved.
Nyckelord
Suspended particle; Shape; Collision; Aggregation; Surface morphology; Stochastic analysis
Publicerad i
Water Research
2014, Volym: 53, sidor: 180-190
Utgivare: PERGAMON-ELSEVIER SCIENCE LTD
UKÄ forskningsämne
Oceanografi, hydrologi, vattenresurser
Fysikalisk kemi
Publikationens identifierare
DOI: https://doi.org/10.1016/j.watres.2014.01.026
Permanent länk till denna sida (URI)
https://res.slu.se/id/publ/111713