US 12,221,369 B2
Method and apparatus for nutrient removal using anoxic biofilms
Charles Bott, Virginia Beach, VA (US); Stephanie Klaus, Virginia Beach, VA (US); Michael Parsons, Virginia Beach, VA (US); Haydee De Clippeleir, Washington, DC (US); Christine deBarbadillo, Washington, DC (US); Bernhard Wett, Innsbruck (AT); and Sudhir Murthy, Herndon, VA (US)
Assigned to Hampton Roads Sanitation District, Virginia Beach, VA (US); and D.C. Water and Sewer Authority, Washington, DC (US)
Filed by Hampton Roads Sanitation District, Virginia Beach, VA (US); D.C. Water and Sewer Authority, Washington, DC (US); Bernhard Wett, Innsbruck (AT); and Sudhir Murthy, Herndon, VA (US)
Filed on Mar. 14, 2022, as Appl. No. 17/654,796.
Claims priority of provisional application 63/267,029, filed on Jan. 21, 2022.
Claims priority of provisional application 63/160,467, filed on Mar. 12, 2021.
Prior Publication US 2022/0289606 A1, Sep. 15, 2022
Int. Cl. C02F 3/30 (2023.01); C02F 101/16 (2006.01)
CPC C02F 3/307 (2013.01) [C02F 3/301 (2013.01); C02F 2101/16 (2013.01); C02F 2203/006 (2013.01); C02F 2209/14 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A wastewater treatment apparatus, comprising: an influent containing contaminated water; a biological nitrogen removal reactor having an inlet configured to receive the influent and a volume, or a series of volumes, configured to contain and treat the contaminated water in one or more reactions, including (1) pre-anoxic selector zone located in an upstream portion of the biological nitrogen removal reactor configured to select organism for a reduction of nitrate or nitrite, having a biofilm media comprising an anammox biofilm or (2) a famine zone located in a downstream portion of biological nitrogen removal reactor configured to select organism for a reduction of nitrate or nitrite, having a biofilm media comprising an anammox biofilm; an effervescence diffuser located below or proximate to the biofilm media in the biological nitrogen removal reactor and configured to emit an intermittent gas bubble discharge, the effervescence diffuser being further configured for turbulence, to manage biofilm sloughing on the biofilm media, to manage mass transfer of substrate to the biofilm media, or to promote floatation or immersion,
and a clarifier located downstream of the biological nitrogen removal reactor and configured to receive a solid-liquid mixture from the biological nitrogen removal reactor; wherein: the biofilm media is either moving, mobile, positioned or fixed in the anoxic selector zone to promote either complete mixed or plug flow conditions for the biofilm media; the biofilm media comprises a single media cassette, or a series of media cassettes, or moving or mobile having the anammox biofilm grown on a media; and the effervescence diffuser includes a gas supply coupled, directly or indirectly, to an air blower, an air compressor, or an inverted siphon.