Limit of treatment nutrient removal in cold climate

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Research will address a major problem facing all Canadian municipalities: how to economically upgrade the existing wastewater treatment processes to ever more stringent effluent quality in terms of lowering the nutrients content (nitrogen and phosphorus). Biological nutrient removal (BNR) offers the lowest cost treatment to avoid fertilization of receiving waters. In some cases limit-of-treatment effluent levels must now be met in existing, tight urban infrastructure. Treating cold, dilute wastewater in such conditions is difficult and leads to the costs of new or upgraded plants taht may overwhelme a municipality, e.g. the upgrade to BNR of Winnipeg's three plants, budgeted at $500 M, is now estimated to cost over $1 billion. Organizing the 2005 IWA International BNR conference in Krakow and the BNR Limit of Treatment Workshop in Washington in 2006, the Applicant has invited the world's most accomplished BNR experts to suggest solutions to these issues. Based on their input and in anticipation of the 2007 completion of Canada's first full scale sludge liquor nitrogen removal plant in Winnipeg-North (based on the Applicant's NSERC-funded research) it is proposed to investigate: acceleration of total nitrogen removal in cold climates through bio-augmentation, anoxic stress and internally generated sources of biodegradable carbon - the latter to moderate the dilution caused by storm-water and infiltration. A process removing total nitrogen on the membrane-based biofilm, further reducing the required treatment time will be developed. An anaerobic autotrophic process called Anammox will be investigated as well as granular activated sludge process - the latter offers easier biomass separation and smaller tank sizes. The work will receive the input from practitioners, including the "father" of BNR - Dr J. Barnard, who was consulted on the ideas and will continue to be involved. Winnipeg offers the potential for fast-track application of generated ideas as the City eagerly seeks lower budget and smaller footprint solutions to the plants' upgrade. Any improvement in the BNR process and associated solids management will decrease the financial burden to the Winnipeg and Canadian taxpayer.