Fluidization with hot compressed water in micro-reactors

On importance of surface forces in a microfluidic fluidized bed

“…We can see from this figure that the adhesion force becomes comparable to the drag force (ratio below 10) for approximately 300 µm glass particles and 2.5 mm PMMA particles, while they are equal for approximately 1 mm and 8 mm glass and PMMA particle diameter respectively. Based on this analysis and assuming a bed-to-particle ratio of 10, which is typical in micro-fluidized bed studies (Doroodchi et al, 2012;Potic et al, 2005;Zivkovic et al, 2013b), the rough boundary between micro-and macro-fluidization can be estimated to be between 1-10 mm for glass particles and between 10-80 mm for PMMA particles.…”

“…The first design was the simple dam distributor (380 μm wide with 10 μm gaps on both side) shown in Fig. 1(a), which was inspired by the non-conventional distributor of Potic et al (2005). This design was particularly attractive due to the ease of manufacture, but experience as well as computational fluid dynamics (Zivkovic et al, 2010;Zivkovic et al, 2013c) showed that fluid flow was not as uniform as would be liked.…”

“…They have, however, not been exploited at all in the microfluidics context. Recent modelling (Derksen, 2008(Derksen, , 2009) and experimental work (Doroodchi et al, 2012;Potic et al, 2005;Zivkovic et al, 2013a;Zivkovic et al, 2013b) has demonstrated that microfluidic fluidized beds (termed henceforth 'microfluidized beds') are feasible, offering the potential to not only overcome diffusion-limited heat and mass transport in simple micron-sized channels, but also provide higher sensitivity and multi-modal detection in the diagnostic context by virtue of the large surface area per unit volume that comes from use of micro-particles (Derveaux et al, 2008;Lim and Zhang, 2007).…”

A Review on Supercritical Fluidization

“…Potic et al [13] [18] simulated the feeding methods of a SCW fluidized bed reactor based on the Eulerian two-flow model incorporating particle kinetic theory. Bubbling phenomenon of Geldart Group B particles was observed in the simulation results.…”

“…They provided a comprehensive picture for the supercritical CO 2-fluidized bed when the superficial velocity was not very high. Potic et al [13] visually studied the fluidization process of Geldart Group A particles in high pressure water within a cylindrical quartz reactor with an internal diameter of 1.0 mm in the range of 0.1-24.4 MPa and 20-500 . Lu et al [14] experimentally obtained the minimum fluidization velocity by measuring the pressure drops of a SCWFB with a diameter of 35 mm for temperature ranging from 360 to 420 C and pressure ranging from 23 to 27 MPa.…”