Analysis of Dialysis through Flat-Plate Membrane Modules
| Autor: | Min-Jie Hsieh, 謝明婕 |
|---|---|
| Rok vydání: | 2002 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 90 A study on membrane dialysis in rectangular mass exchangers has been carried out under concurrent-flow, countercurrent-flow and cross-flow operations. It was found that mass transfer of dialysis in rectangular mass exchangers of microporous membrane can be analogous to heat transfer in rectangular heat exchangers. The separation efficiency increases with the flow rate of the retentate phase, or with the flow rate of dialysate phase, or with the ratio of the flow rate of the dialysate phase to that of the retentate phase. Under comparable conditions most solute is dialyzed in countercurrent-flow arrangement, the least in concurrent flow. However, the separation efficiencies of three flow-type devices approach one when the flow rate in the retentate phase or in the dialysate phase becomes very large. Theoretical prediction of solute concentration for the system of dialysis coupled with ultrafiltration in cross-flow membrane modules was obtained by an approximate solution and thus separation efficiencies could be calculated for various operating and design conditions. The overall mass transfer coefficient was assumed to be constant and the concentration polarization and pressure drop on both compartment were neglected in solving this problem. It was found that increasing the flow rate in retentate phase is more beneficial to the mass transfer than increasing in dialysate phase. The performance of dialysis can be improved significantly by the effect of ultrafiltration. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|