Composition of extracellular polymeric substances in a partial nitrification reactor treating high ammonia wastewater and nitrous oxide emission

Effect of influent COD/N ratio on performance and N2O emission of partial nitrification treating high-strength nitrogen wastewater

“…The compositions of synthetic nitrogenrich wastewater was as follows (per liter): CH 3 COONa, 100-500 mg; NH 4 Cl, 200 mg; K 2 HPO 4 , 112 mg; The compositions of synthetic nitrogenrich wastewater was as follows (per liter): CH 3 COONa, 100-500 mg; NH 4 Cl, 200 mg; K 2 HPO 4 , 112 mg; …”

“…This kind of wastewater has a wealth of sources such as ammonia and nitrogenous fertilizer industrial wastewater, leather wastewater and food industry wastewater. 3 It was reported that the numbers of AOA amoA genes was correlated negatively to the ammonium levels in wastewater, thus AOB was supposed to be play the dominant role in nitrication process treating high-strength nitrogen wastewater. Biological nitrogen removal (BNR) has been widely used as one of the most effective and economical methods for removal of nitrogen from wastewater.…”

Nitrogen removal via nitrite in a partial nitrification sequencing batch biofilm reactor treating high strength ammonia wastewater and its greenhouse gas emission

“…The main influencing factors to achieve and maintain PN process are including dissolved oxygen (DO), pH value, sludge retention time (SRT), free ammonia (FA) and free nitrous acid (FNA) etc (Wei et al, 2015a). Till now, most of partial nitrification processes are reported by using synthetic wastewater as substrate under well-controlled laboratory-scale activated sludge reactors (Chen et al, 2016).…”

Organic loading rate shock impact on extracellular polymeric substances and physicochemical characteristics of nitrifying sludge treating high-strength ammonia wastewater under unsteady-state conditions

“…The long-term oxygen stress led to a loss of activity in nitrite oxidation rather than ammonia oxidation. 24 During the operation, the specic nitrication rate decreased dramatically from 38 MLVSS h when the OLR was reduced to 0. Furthermore, simultaneous denitrication occurred at all operation stages, whereby the denitrication rate improved markedly aer the addition of organic carbon with the OLRs increasing from 0 to 0.30 kg COD per kg MLVSS d, but seriously deteriorated as the OLRs increased to 0.75 kg COD per kg MLVSS d. These results indicated that sufficient electron donors were necessary for denitrication, but an overload of organic substrates under the high-strength ammonia condition would cause the inhibition of 12,13,27,28 Previous studies showed that the oc size and F/ M were positively 7,12,27 or negatively 28 correlated or even that there was no clear relationship.…”

“…Peak D was located at 275-285/450 nm, representing the fulvic acidlike substances. 37,38 At the initial stage with the OLR of 0, the aromatic PN-like substances (peak A) were found to be the prominent peak in the EEM spectra of LB-EPS, and gradually disappeared as the COD/N increased to 4. The tryptophan PNlike substances (peak B) showed few variations in LB-EPS under all OLRs, except for high uorescence intensities observed at the nal cultural period at the OLR of 0.…”