Deterioration of the anammox process at decreasing temperatures and long SRTs

The implementation of autotrophic nitrogen removal in the mainstream of a municipal wastewater treatment plant is currently pursued. Among the crucial unknown factors are the kinetic properties of anaerobic ammonium oxidising (anammox) bacteria at low temperatures. In this study we investigated the adaptation of a fast-growing anammox culture...

Treatment of sidestream dewatering liquors from thermally hydrolised and anaerobically digested biosolids

A long term operation (22 months) of the sidestream treatment plant at the water and resource recovery facility at the Tilburg sewage works in The Netherlands is presented. This plant treats dewatering reject liquor from thermally hydrolysed (THP) and mesophillic anaerobically digested (MAD) biosolids. The sidestream plant is comprised of a...

Hydroxylamine metabolism of Ca. Kuenenia stuttgartiensis

Hydroxylamine is a key intermediate in several biological reactions of the global nitrogen cycle. However, the role of hydroxylamine in anammox is still not fully understood. In this work, the impact of hydroxylamine (also in combination with other substrates) on the metabolism of a planktonic enrichment culture of the anammox species Ca....

Hydroxylamine and the nitrogen cycle: A review

Aerobic ammonium oxidizing bacteria were first isolated more than 100 years ago and hydroxylamine is known to be an intermediate. The enzymatic steps involving hydroxylamine conversion to nitrite are still under discussion. For a long time it was assumed that hydroxylamine was directly converted to nitrite by a hydroxylamine oxidoreductase....

Adaptation of anammox bacteria to low temperature via gradual acclimation and cold shocks: Distinctions in protein expression, membrane composition and activities

Anammox bacteria enable efficient removal of nitrogen from sewage in processes involving partial nitritation and anammox (PN/A) or nitrification, partial denitrification, and anammox (N-PdN/A). In mild climates, anammox bacteria must be adapted to ≤15 °C, typically by gradual temperature decrease; however, this takes months or years. To...