     Downloads - Reports
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| D7 - Nonwoven textile for MBR filtration | |
| Project | AMEDEUS |
| Date | 11.5.2010 |
| Abstract | Results achieved during the first year of the project showed that the stationary flux of the textile filters is in the range of the microporous polymeric membranes and they have a higher initial flow and a higher permeability then the reference. During long term filtration some textiles clogged very quickly and showed a deficient permeate quality. Crucial points to be solved are the pore size (distribution) and the roughness of the material. From the chemical point of view, textile seems to ensure the same performances in comparison with the conventional membranes and the polypropylene nonwoven seems to ensure the best resistance. The characterisation of both newly realised membranes and commercial membranes showed that the textile membranes have larger pore sizes then the conventional ones with a large pore distribution, even if by modifying production conditions it is possible to control this parameter. Since a random distribution of fibres generates the webs, higher roughness was recorded for textile filters even if the tests realised on newly realised membranes indicate that it’s possible to reduce it, by controlling the production working parameters. The optimisation on the production of the nonwoven membrane in term of thickness and density of the polymer can also increase the possibility of the application of these textiles as replacement for membranes in MBR plants. In order to easily solve the limits of the textile filtration media electrospinning seems to be a promising option. The coating of nanoweb allows reducing some critical points, such as porosity and roughness mainly responsible for the low filtration performances. During long term operation on the TBR, the nanocoated material showed better results than the coarse nonwoven delivered by Freudenberg. It was possible to operate the nanocoated module at a flux of 30L/(m2h) for 3d. The test cell trials indicate that fluxes up to 150 L/(m2h) might be possible. Further studies are necessary here. Investigations of the number of bacteria in the permeate showed that these decrease with time due to the build up of the filter cake. The high standard of MBR effluent was not reached within the 5 days operation time. Further research is necessary in the field of permeability recovery by physical/chemical cleaning, as fouling and cleaning phenomena might strongly differ from conventional microporous membranes. |
| Pages | 49 |
| Download | pdf (3.00 MB) |
