2017 Volume 71 Issue 3 Pages 183-188
We explain the experiments and analysis results for a dialyzer-type forward osmosis（FO）module composed of hollow fiber membranes. In an FO system, low concentration solutions（FS: Feed Solution）flow in a lumen of hollow fiber membrane, while high concentration solutions（DS: Draw Solution）are supplied outside of it in with a counter current mode. FO test conditions, a 3.5 wt％ NaCl soln. in the FS and 5, 7 and 10 wt％ NaCl solns.in the DS were selected, and quasi-PRO test conditions, pure water in the FS and a 3.5 wt％ NaCl soln.in the DS, were adopted. Effects on the flow rates of the FS and the DS by changing their values were also studied. Membrane transport equations were derived, consisting of two external concentration polarizations and an internal concentration polarization. The previous hemodiafiltration module model, involving the above membrane transport equations as a basic membrane transport model, was introduced to the numerical analysis for this FO system. It was demonstrated that the presented module model provides a reasonable explanation for FO test data of permeated water flow rates and outlet solute concentrations of the DS and the FS.
