AN INTEGRATED OXIDATION-REDUCTION PLATFORM FOR DISINFECTION, MICROCONTAMINANT DESTRUCTION AND NUTRIENT REMOVAL

Onsite wastewater treatment systems (OWTS) are under increasing pressure to satisfy stringent discharge requirements for pathogen removal and nutrient loading and enhance reuse capabilities. An innovative oxidation/reduction platform suitable for application in remote environments offers the potential to reliably disinfect, destroy a broad spectrum of microcontaminants and reduce nutrients to non-detect levels. The capabilities of the HiPOx advanced oxidation reactor for microcontaminant destruction (synthetic organic compounds including endocrine and pharmaceutically active compounds) are well established. The ability of the same system operating in an ozone-only mode to achieve reclaimed water regulatory criteria free of disinfection byproducts is currently being demonstrated on a variety of secondary and tertiary effluents. Initial testing conducted on secondary effluents indicates consistent 3.5 to 4 log removal of total coliform at ozone doses below 10 mg/L. Indicator viruses tested were very susceptible to low-dose ozonation. The ability of the membrane biofilm reactor (MBfR) technology to denitrify and remove recalcitrant forms of soluble and colloidal organic nitrogen and phosphorous is also being demonstrated. Pilot scale studies of the MBfR processes for autotrophic denitrification with hydrogen have shown the ability to drive nitrate concentration to levels below 0.1 mg/L with concurrent removal of other oxidized contaminants. The integration of these technologies into a single platform for application to existing and proposed OWTS offers the potential to cost effectively achieve very stringent performance requirements and enhance reuse capabilities.