K Northcott, B Freidman, G Stevens, I Snape, K Mumford
Publication Date (Web): 16 March 2016

Industry participation in water and waste management projects in polar areas presents opportunities for improvement of treatment technologies in the broader global context. For this reason it is useful for industry to build strong partnerships with organisations involved in polar research.

Veolia is working with the University of Melbourne under a five-year Memorandum of Understanding (MoU) to collaborate on research into better water and waste treatment technologies. The first major project is currently focused on sites at Australia’s Casey Station, operated by the Australian Antarctic Division (AAD), in East Antarctica. This project aims to utilise low-energy biological processes, such as biofiltration, to remediate summer melt water contaminated with diesel-based hydrocarbons.

The collaboration between Veolia and the University of Melbourne leverages 15 years of Antarctic permeable reactive barrier (PRB) research into ion exchange/adsorption of inorganics and organics, as well as characterisation of biofilms on activated carbon. This has enabled the team to develop advanced analytical techniques for Antarctic research, and apply them to more conventional water treatment. Knowledge gained from analysis of carbon samples from Antarctic PRBs has been used to better understand the performance of large-scale biological activated carbon (BAC) filtration processes used in municipal water treatment.

Key research questions that the project partners are interested in include:

  • What are the key bacterial species present on BAC that are associated with removal of natural organic matter (NOM), nuisance and toxic organic species in water?
  • What is the fate and accumulation on activated carbon of inorganic constituents in water?
  • What are the limiting factors for growth of certain bacterial species on BAC? 

The answers to these questions have significant impact on the management and optimisation of biofiltration processes, both in polar and temperate regions.

The research is yielding results that indicate direct comparisons between the behaviour of activated carbon and other reactive media in PRBs in Antarctica, and those of municipal BAC filtration plants in Australia. There are similar bacterial communities present, particularly with those bacteria capable of oxidising dissolved iron and/or manganese. In spite of differing feedwater composition, and resulting mineral composition, these bacterial communities produce impressive biologically derived mineral structures (biogenic materials) with strikingly similar morphologies. These biogenic processes were evident in all samples collected. This reinforces the relevance of remote region PRB research to inform the operation of municipal water treatment plants that employ biofiltration technologies.

Utilising the techniques developed for Antarctic PRBs, we have been able to better understand the structure and ecology of biofilms that establish in municipal BAC filters. The retention and accumulation of inorganics through biogenic mineral formation in BAC filters, and their abundance across varying feedwater conditions and media types, suggest that these minerals may:

  • Offer the potential for removal of a wide range of aqueous pollutants, including heavy metals and toxic organics; and
  • Extend the performance of activated carbon beyond what would be considered its typical adsorptive capacity. 

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