The utilization of membrane treatment for the production of potable water has become more prevalent in today's industry. As drinking water regulations become more stringent this trend is expected to continue. Widespread use is also a result of membrane treatment being the best available treatment in many cases. While membrane treatment is a proven technology that can produce a consistently superior product to conventional treatment methods, membrane fouling and concentrate disposal are issues that drive up the cost of membrane treatment and can effectively eliminate it from consideration as a treatment alternative. This research focused on membrane fouling. A series of filtration experiments were conducted on various membranes to investigate the physical and chemical factors that influence fouling. The effects of both organic and colloidal fouling were explored by conducting research on various commercial membranes and experimental membranes by Saehan Industries, Inc. (Saehan). Saehan's membranes were in various stages of development in their process of creating a more fouling resistant membrane (FRM). Various hydrodynamic and chemical conditions were used to characterize the evolution of the Saehan commercial products to the experimental FRMs. The developmental stage of the membrane tested included analysis of the various trade secret coating techniques termed single, double, and special. A proprietary post-treatment process was also utilized in combination with each of the coating techniques. The developmental membranes were also compared to commercially available FRMs. The existing FRMs showed better fouling resistance than Saehan's commercially available products in high organic surficial groundwater testing. Synthetic colloidal water testing demonstrated the superior performance of the FRMs, but was not acute enough to differentiate the fouling performance within the group of FRMs or Saehan products. Average roughness decreased slightly as coating technique progressed from single to double to special. Post-treatment increased roughness in single coated membranes and reduced the roughness in double and special coated membranes. The relative charge differences in the developmental membranes were exhibited among non post-treated membranes. Post-treatment membranes did not demonstrate relative surface charge differences consistent with the manufacturer. Initial mass transfer coefficient, determined by clean water testing, increased as coating moved from single to double to special. Clean water testing showed increased initial mass transfer coefficient for membranes with post-treatment. Single coated membranes showed the best salt rejection capability among non post-treated membranes. Post-treatment increased selectivity for all membrane coating techniques. The coating effect on fouling potential had an inverse relationship between single coated versus double and special coated membranes. The post-treatment increased fouling resistance for the single coated membranes, but decreased fouling resistance of double and special coated membranes. The SN7 membranes showed the best performance of the developmental membranes.
| Identifer | oai:union.ndltd.org:ucf.edu/oai:stars.library.ucf.edu:etd-2125 |
| Date | 01 January 2006 |
| Creators | Doan, Matthew |
| Publisher | STARS |
| Source Sets | University of Central Florida |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Electronic Theses and Dissertations |
Page generated in 0.0024 seconds