碩士 / 國立成功大學 / 機械工程學系碩博士班 / 91 / Among many seawater desalination methods, membrane desalination (MD) possesses the advantages that exist in the conventional membrane separation and that coming from the conventional distillation methods. However, MD method has not yet become available for commercial application. Since, the MD process is a thermal-driven method, fouling is more likely to accumulate on MD membrane than that on RO membrane. Membrane fouling thus posts as one of the major obstacles for MD method to compete with other desalination method. Up to this point, membrane fouling is inevitable, but can be effectively mitigated by a proper pretreatment before MD separation.
In this study, different single-pretreatment modules (including 1μm MF, sand filter, GAC, ion exchange resin, ultraviolet) was used to investigate the individual effect on membrane fouling. Results show 1μm MF and UV can effectively slow down membrane fouling. In order to seek a more effective pretreatment system, four combination systems were selected to perform the desalination tests. These pretreatment systems are: (1) sand filter + GAC + ion exchange resin (system 1); (2) UV + 1μm MF (system 2); (3) UV + 0.2 μm MF (system 3); (4) UV + 0.001 μm UF (system 4). Results obtained from system tests indicate that UV+ 0.2μm MF and UV + 0.001μm UF can more effectively slow down the fouling speed and extend the operation time.
From our previous investigations, ultrasonic cleaning technique was found very effective in cleaning out the membrane fouling and restore the declining permeate flux. In this study, the details of membrane structure before and after ultrasonic cleaning were examinated by SEM (scanning electron microscope). The foulant accumulated under a better pretreatment system(such as UV+ 0.2μm MF and UV + UF) can be removed more thoroughly than the foulant accumulated under a traditional pretreatment system and cleaned up by the same ultrasonic cleaning device.
| Identifer | oai:union.ndltd.org:TW/091NCKU5490113 |
| Date | January 2003 |
| Creators | Henry Chiou, 邱宏茂 |
| Contributors | Jenq-Shing Chiou, 邱政勳 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 81 |
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