Scale‐Up of Oscillatory Helical Baffled Reactors Based on Residence Time Distribution

Abstract

For the first time, the scale‐up of oscillatory helical baffled reactors (OHBR) was studied. Residence time distributions were used to assess the scale‐up over a wide range of net flow Reynolds numbers and oscillation conditions. A simple scale‐up correlation based on oscillation and net flow conditions was established to predict the plug flow behavior at various reactor scales. It is suggested that operating conditions can be easily extrapolated from the laboratory scale to the pilot scale, and even to industrial scales, as the mixing behavior is similar.

Mass transfer enhancement as a function of oscillatory baffled reactor design

“…2(c)-bubbly flow), as it does not have sharp edges and the consequent increased shear. The OHBR and OR had similar flow regimes which confirms that the intensity of swirling flow generated by the oscillatory flow and helical baffle [28] was not strong enough to promote coalescence and break-up phenomena, exhibiting little effect on the bubble size comparing with the other baffle designs.…”

“…The OR exhibited the lowest enhancement in mass transfer (Table 4) where the kLa values, 0.0076 s -1 and 0.01s -1 at vvm=0. 28 and 0.64 respectively, at no oscillation, Reo=0 (BC), were lower than that for the other designs in all cases, and increased monotonically with Reo. This confirms the importance of baffles in a gas-liquid contactor.…”

Predicting power consumption in continuous oscillatory baffled reactors

“…The Strouhal number measures the effective eddy propagation with relation to the tube diameter. Higher values of ;< will promote the propagation of the eddies into the next baffle (Ahmed et al, 2017). The most common range of the Strouhal number used in the literature is 0.15 < ;< < 4 (Abbott et al, 2012).…”

Scale-Up of Gas–Liquid Mass Transfer in Oscillatory Multiorifice Baffled Reactors (OMBRs)

“…The oscillation amplitude was shown to have a stronger effect on k L a than the oscillation frequency. , Multiorifice baffles have been shown to cause a high degree of plug flow and display a wider operating window for bubbly flow and higher rates of mass transfer than other designs, including helical, single-orifice, and integral baffle design . In addition, the multiorifice design has been suggested to be the most appropriate for gas–liquid systems as it allows good control of bubble size. − Although parameters such as oscillation conditions, gas velocity, and baffle design have been studied, there have not yet been any studies dealing with the effect of OBR scale up.…”