| abstract |
A method and system of treating wastewater is disclosed. The treatment system has a nitrification-denitrification system comprising a sorption system, a biofilm system, and an anaerobic digester that digests or converts at least a portion of the solids or sludge from the sorption system and biofilm system. The method can comprise providing a wastewater to be treated and denitrifying the wastewater in a first biological reactor to produce a denitrified mixed liquor, nitrifying the denitrified mixed liquor with a nitrifying biofilm on a earner and biosorbing undesirable constituents from the denitrified mixed liquor with a suspended biomass in a second biological reactor, and separating a first portion of the nitrified mixed liquor in a separator to produce a solids-rich sludge and a treated effluent having a total nitrogen concentration of less than about 10 milligrams of elemental nitrogen per liter. |