A solution of sucrose (Mw:342g/l) is concentrated using a tubular nanofiltration membrane with an internal diameter...

 

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A solution of sucrose (Mw:342g/l) is concentrated using a tubular nanofiltration membrane with an internal diameter of 6mm. The membrane shows a complete rejection for sucrose. With a feed solution of 5wt% at 20 C and a pressure of 20 bar, a flux of 33.5 l/mh is measured at a cross-flow velocity of 0.5 m/s while at a velocity 4.5 m/s a flux of 48.9 l/mh is measured (a) Calculate the concentration polarisation modulus for both flow rates (b) Calculate the flux at 10 bars, assuming that concentration polarisation remains the same and with an osmotic pressure of 7.9bar (c) Is the assumption of concentration polarisation correct? p=103 kg/m; -1.1*103 Pa.s; a=0.05; Dsucr=4.2* 10-10m/s A solution of sucrose (Mw:342g/l) is concentrated using a tubular nanofiltration membrane with an internal diameter of 6mm. The membrane shows a complete rejection for sucrose. With a feed solution of 5wt% at 20 C and a pressure of 20 bar, a flux of 33.5 l/mh is measured at a cross-flow velocity of 0.5 m/s while at a velocity 4.5 m/s a flux of 48.9 l/mh is measured (a) Calculate the concentration polarisation modulus for both flow rates (b) Calculate the flux at 10 bars, assuming that concentration polarisation remains the same and with an osmotic pressure of 7.9bar (c) Is the assumption of concentration polarisation correct? p=103 kg/m; -1.1*103 Pa.s; a=0.05; Dsucr=4.2* 10-10m/s