Mixed solid/dispersed phase particles in multiphase fluidised beds. II: Stability at laminar to turbulent flow scales

• Published in: Chemical engineering science Vol. 55; no. 15; pp. 3033 - 3051
• Main Authors: Niven, R.K., Khalili, N., Hibbert, D.B.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.2000; Elsevier
• Subjects: Applied sciences; Chemical engineering; Decontamination. Miscellaneous; Dispersed phase; Droplet; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Fluidisation; Fluidization; Interfacial tension; Pollution; Pollution, environment geology; Soil and sediments pollution; Turbulence; Turbulence; Dispersed phase; Droplet; Interfacial tension; Fluidisation; Turbulent flow; Hydrocarbon; Interface tension; Diesel fuel; Liquid fluidization; Rupture; Thermodynamic stability; Fluidization; Fluid solid; Soil pollution; Retention; Liquid solid; Modeling; Multiphase system; Decontamination; Laminar flow; Gas liquid fluidization; Quartz sand; Gas liquid solid; Thermodynamic analysis; Organic compounds
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/S0009-2509(99)00466-2

An energetics model is developed to explain the retention of a dispersed phase fluid within a multiphase fluidised bed, in terms of the behaviour of mixed phase particles, or composite particles of the solid and dispersed fluid phases. The energy available for mixed phase particle rupture is determined by analogy with the theories of Kolmogorov and Hinze for isolated droplet rupture in turbulent flow, and of Taylor, Sprow, Shinnar and others for droplet rupture in laminar flow fields. The resulting available energy surfaces are compared to the work required for mixed-phase particle rupture, as determined in Part I (Niven et al., 1998. Chemical Engineering Science, submitted for publication). The overall model is used to explain experimental observations of the diesel–sand system fluidised by either water or water and nitrogen. The model may also be applied to other multiphase systems, including ex situ soil washing, tar sand extraction, and colloid-stabilised emulsions.