Hollow fiber reverse osmosis: experiments and analysis of radial flow systems

The performance of a hollow fiber reverse osmosis system was determined experimentally by measuring the fraction of feed recovered as product, φ, and the concentration reduction ratio, θ_p. A predictive model for these two quantities was developed which yields results that agree with the experimental data very well for applied pressures of 300–450 psig., feed rates from 75 to 525 cc/sec and feed concentrations up to 15000 ppm of sodium chloride.The concept of distributed sinks in a continuum is used for the shell side, and a diffusion model is used to describe solute transport across the fiber wall. The principal assumptions made are negligible concentration polarization, small radial pressure drop in the shell and small solute transport, compared with solvent transport, through the fiber. Simple closed form expressions for φ and θ_p, given by eqns (43a) and (51), were obtained which are accurate over the range of experimental conditions employed.