A pH simulator consisting of an efficient numerical solver of a system of nine nonlinear equations was constructed and implemented in the modeling software MATLAB. The pH simulator was integrated in a granular biofilm model and used to simulate the pH profiles within granules performing the nitritation-anammox process for a range of operating points. The simulation results showed that pH profil...

The prerequisite to the development success of the novel mainstream processes partial nitritation/anammox is the out-selection of nitrite oxidizing bacteria (NOB). A recent study suggested that this could be achieved through NO production by ammonium oxidizing bacteria under cyclic oxic-anoxic conditions. Indeed, it is known that among NOB, Nitrobacter species are reversibly inhibited by NO. Ho...

The effect of COD/N ratio on the granulation process and microbial population succession was investigated. Four identical sequencing batch reactors, R1, R2, R3 and R4, were operated with various initial COD/N ratios ranging from 0/200 to 800/200 (m/m). Ethanol was fed as the source of COD. Aerobic granules were successfully cultivated in R2 and R3, operating with the COD/N ratio of 200/200 and ...

This study investigated algal-bacterial shortcut nitrogen removal (SNR) in photo-sequencing batch reactors (PSBRs) for treatment of high ammonium strength wastewater using both experimental and modeling approaches. Bench-scale PSBR studies were carried out under alternating light dark cycles, provided aerobic anoxic conditions that promoted nitritation/ denitritation. Total efficiencies >90% ac...

Nitrogen removal by a nitritationanammox bioreactor at low temperature 1 Ziye Hu, Tommaso Lotti, Merle de Kreuk, Robbert Kleerebezem, Mark van 2 Loosdrecht, Jans Kruit, Mike S.M. Jetten, Boran Kartal 3 a Department of Microbiology, IWWR, Radboud University Nijmegen, 4 Heyendaalseweg 135, 6525AJ Nijmegen, The Netherlands 5 b Department of Biotechnology, Delft University of Technology, Julianalaa...