One of the main challenging issues for aerobic nitrifying granules in treating high strength ammonia wastewater is the long granulation time required for activated sludge to transform into aerobic granules. The present study provides a novel strategy for enhancing aerobic nitrifying granulation by applying an intensity of 48.0mT static magnetic field. The element analysis showed that the applie...

A typical steady state bulk pH of about 5 was established in a nitrifying fluidized bed with chalk as the only buffer agent. In spite of the low pH, high rate nitrification was observed with the nitrification kinetic parameters in the chalk reactor similar to those of biological reactors operating at pH>7. Various methods were used to determine the reasons for high rate nitrification at such lo...

A typical steady state bulk pH of about 5 was established in a nitrifying fluidized bed with chalk as the only buffer agent. In spite of the low pH, high rate nitrification was observed with the nitrification kinetic parameters in the chalk reactor similar to those of biological reactors operating at pH>7. Various methods were used to determine the reasons for high rate nitrification at such lo...

Nitrous oxide (N2O) is produced in the lower Seine river at 40 to 60 kg N-N2O d–1, in a section greatly affected by effluents from the Achères Wastewater treatment plant (WWTP). Because water column denitrification is weak in this sector, we hypothesized that N2O could be produced by the nitrifier-denitrification process. To understand the controls of N2O emission, nitrifying bacterial cultures...

The presence of a copper-containing dissimilatory nitrite reductase gene (nirK) was discovered in several isolates of beta-subdivision ammonia-oxidizing bacteria using PCR and DNA sequencing. PCR primers Cunir3 and Cunir4 were designed based on published nirK sequences from denitrifying bacteria and used to amplify a 540-bp fragment of the nirK gene from Nitrosomonas marina and five additional ...

Methyl fluoride and dimethyl ether were previously identified as inhibitors of ammonia oxidation and N2O production in autotrophic nitrifying bacteria. We demonstrate that methyl fluoride and dimethyl ether are substrates for ammonia monooxygenase and are converted to formaldehyde and a mixture of methanol and formaldehyde, respectively.

In this study, a photo-baffled reactor was operated to assess the performance of microalgal-nitrifying bacteria consortia in treating ammonia with its input concentration up 180 mg-N·L−1. The six-compartment reactor, total effective volume 3.2 L, run continuously for 350 days at 30 °C. Overall, 66 ± 11% removed nitrogen loading rate 0.083 0.011 kg-N·m−3·day−1. addition, long-term, stable partia...