The objective of this project is to demonstrate the feasibility of increased water recovery from organic-laden process streams by applying NF where it has previously been hard to use to concentrate the organic components in the process stream.
This will be done by addressing 3 issues that have been potential barriers to NF use:
1. NF membrane fouling by the process stream;
2. NF concentrate disposal;
3. Integration with other processes to allow NF permeate to be reused rather than discharged.
NF membrane fouling will be reduced by the following strategies:
1. Pre treatment with a novel compact softening process combining precipitation and filtration leading to adsorptive removal on a renewable adsorbent (the precipitate from the softening reaction) Two. Membrane surface modification involving in situ graft polymerisation of monomers on the membrane surface using redox initiators to generate radicals on the surface.
This method potentially allows in situ modification of commercial spiral wound elements. Three. Adaptation of commercial cross-rotational UF module to use NF membrane instead. The better mass transfer provided by this module has been demonstrated by several fold flux increase in past UF applications. Downstream processing will involve the following treatments: NF - concentrate - biodegradation or biotransformation in a membrane bioreactor. Ozonolysis may be coupled with the biodegradations to breakdown refractory materials. NF-permeate - ozonolysis, UV to further breakdown LMW organics that pass through the NF membrane, further treatment of salt mixtures if necessary. The combining of these processes will be mathematically modelled in order to identify regions for optimal operation with respect to operating costs. Initial technical feasibility will be demonstrated by running 2-4 on site demonstrations for 2-6 months treating slipstreams (up to 100 LPM) of the user partners. Operational goals are to demonstrate potential recovery of at least 90% of water volume in the slipstream and reduction of the volume of organic concentrate requiring disposal to less than half of what would be generated in conventional NF processes.
Funding SchemeCSC - Cost-sharing contracts
BD12 9EJ Wyke - Bradford
84101 Beer Sheva