Vibratory Shear Enhanced

Vibratory Shear-Enhanced Membranes The vibratory shearenhancing process (VSEP) is j ist starting commerciahzation by Logic International, Emeryville, CA. It employs the nse of intense sinnsiodal shear waves to ensnre that the membrane snrfaces remain ac tive and clean of sohd matter. The application of this technology wonld be in the pnrification of wastewater (Ref. 2). 

FIGURE 8.36 Comparison of variation of permeate flux with mean waU shear stress two-phase flow. Dean, and vibratory shear-enhanced process (VSEP) system. (From Figure 6 in Al-Akoum, O., Mercier-Bonin, M., Ding, L., Fonade, C., Aptel, P., and Jaffrin, M.Y., Desalination, 147, 31, 2000. With permission.)... 

Vibratory membrane techniques are characterized by vibrating the membrane at certain frequency and amplitude. The vibration techniques used in the membrane filtration enhancement include the high-frequency circular vibration, for example, vibratory shear-enhanced process (VSFP), and low-frequency vibration for hollow fiber membrane filtration. 

Petala MD, Zouboulis AI. Vibratory shear enhanced processing membrane filtration applied for the removal of natural organic matter from surface waters. J. Membr. Sci. 2006 269 1-14. 

The VSEP (Vibratory Shear Enhanced Processing) system made by New Logic Research is an example of the vibration technique. It uses a stack of circular membrane discs, each with membrane media on both sides, enclosed in a relatively small housing (over lOOm of membrane area in less than 200 litres of housing volume). The stack is then vibrated torsionally, i.e. in a direction parallel to the discs. 

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