Assays were carried out to evaluate the dissolved oxygen uptake resulting from mineralization of humic substances (fulvic acid (FA) and humic acid (HA)) from different sources: sediment, dissolved organic matter (DOM) of 120-day decomposed aquatic macrophyte (Scirpus cubensis and Cabomba piauhyensis), and lagoon DOM. The experiments were also aimed at estimating the oxygen uptake coefficient of...

Colfax, WA, operates an aerated lagoon to achieve compliance with its National Pollutant Discharge Elimination System (NPDES) permit, which currently requires biochemical oxygen demand (BOD) and total suspended solids (TSS) removal. However, ammonia removal may soon be required, and Colfax is considering a nitrifying trickling filter (NTF) that would allow them to also maintain the lagoons. To ...

Nitrification is a necessary and often limiting process in animal waste treatment for removal of nitrogen as N2 through biological nitrification/denitrification systems. We evaluated three technologies for enhancing nitrification of pig lagoon wastewater prior to denitrification: overland flow, trickling filter, and a bioreactor using nitrifying pellets. The overland flow system consisted of a ...

Nitrification of ammonia (NH4) is a critical component for improved systems of animal wastewater treatment. One of the most effective processes uses nitrifying microorganisms encapsulated in polymer resins. It is used in Japan in municipal wastewater treatment plants for higher nitrification rates, shorter hydraulic retention times (HRT), and lower aeration treatment cost. We evaluated whether ...