الفهرس | Only 14 pages are availabe for public view |
Abstract Membrane separation processes are finding progres-sively wider pplications in medicine and industry. The polarization effect is very severe in most liquid-phase processes because of the extremely small diffusion coefficient. The present thesis is concerned with the ability of turbulence promoters to enhance the rate of mass transfer in dialysis. Four alternative detached turbulence promoters types were suggested, tested and ”evaluated. These were respectively,cylindrical, square and rectangular rods turbulence promoters as well as nets (screens). Accordingly, pressure drop and concentration data for sodium chloride solution and cellulose acetate membranes were determined in a thin channel laminar flow cell for the different turbulence promoters investigated. The experimental work aimed at investigating the effect of pitch to diameter ratio, S/E, 9f the rod type promoters .on both mass transfer and cell pressure drop. ” For the net (screen) type promoter the effect of net element inclination with longitudinal cell axis was investigated. Experiments were performed in the laminar regime up to Re~’1l70. Empirical relationships were developed that allow the prediction of performance of any of the investigabed . |