Coalescence efficiency model including electrostatic interactions in liquid/liquid dispersions. (14th April 2015)

• Record Type: Journal Article
• Authors: Kamp, Johannes; Kraume, Matthias
• Is Part Of: Chemical engineering science. Volume 126(2015)
• Page Start: 132
• Page End: 142
• Publication Date: 2015-04-14
• Subjects: Population balance -- Coalescence -- DLVO -- Electrostatic force -- Zeta potential -- Coalescence efficiency; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2014.11.045
• Languages: English
• ISSNs: 0009-2509

Abstract

Abstract: The drop size distribution is an essential process variable in liquid/liquid systems and relevant in many technical applications. It can be described by population balance equations. A coalescence efficiency model was developed to be able to describe the well-known coalescence inhibition due to changing pH value or salt concentration. The model includes the attractive van der Waals and repulsive electrostatic force according to the DLVO theory into the population balance equation framework. This DLVO model can extend existing simulations in a straightforward manner due to a conceptual implementation. Moreover, zeta potential measurements were performed and the model was applied to simulate experiments in a stirred tank. Hence, the drop size distribution could be predicted well with changing pH value. The results are discussed in comparison to simulations with existing models in literature. Highlights: New coalescence efficiency model for population balance equation. Implementation of repulsive electrostatic and attractive van der Waals forces. Extension of hydrodynamic models describing coalescence efficiency. Zeta potential investigations and description by Stern adsorption isotherm. Successful simulation of drop size distributions in stirred tank with changing pH.