A UF membrane is first tested in a stirred cell in which there is no concentration polarization. Experimental values obtained are listed in the following table. Then the same membrane is used in a spiral-wound module in which there is concentration polarization. Values listed are obtained. Assume membrane thickness and permeabilities are the same. Estimate \(\mathrm{R}^{\mathrm{o}}{ }_{\mathrm{c}}\) from stirred-cell data, and assume inherent membrane rejection is unchanged. Calculate expected solvent flux and concentration polarization modulus \(\mathrm{M}_{\mathrm{c}}\) in the spiral-wound membrane system. No gel layer forms. Use concentration units, \(\mathrm{g} / \mathrm{L}\). Assume density \(=0.997 \mathrm{~kg} / \mathrm{L}\).

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Cout (conc. solute) Cp (conc. solute) J'solv g/ms 4p, bars Stirred Cell 10.0 g/L 0.30 g/L 69.25 3.0 Spiral Wound 8.0 g/L 1.0 g/L 3.5