Autotrophic ammonium removal from reject water: partial nitrification and anammox in one‐reactor versus two‐reactor systems

Abstract

Removal of total nitrogen from anaerobically digested sludge reject water by a fully autotrophic process in either one- or two-reactor systems was compared. Autotrophic nitrogen removal is currently most often applied in the one-reactor system primarily in the DEMON configuration. The two-reactor systems had a similar nitrogen removal rate to the one-reactor systems. It was evident that the limiting step was partial nitrification. Increase in partial nitrification can be difficult in a one-reactor system, where the overall conditions, such as the oxygen concentration or substrate concentrations, would progress to full nitrification. The partial nitrification of the two-reactor system may be improved by adjusting key parameters: the un-ionized form of the substrates, the oxygen concentration or the solids residence time. The impact of two process configurations on the operational stability and process performance was presented based on two cases--DEMON and the SHARON-ANAMMOX process.

High-throughput nitritation of reject water with a novel ammonium control loop: Stable effluent generation for anammox or heterotrophic denitritation

“…As stated in several studies, the actual bottleneck in the overall capacity of N-removal advanced treatment systems is the limiting capacity of the PN compared to anammox capacity [6,8,28]. Consequently, the novel technology presented in this study can be useful to improve the capacity of N-removal via nitrite.…”

“…Consequently, the development of robust technologies for PN at higher nitrogen loading rates (NLR) is required to improve the capacity of the autotrophic N-removal [8].…”

Fast start-up and controlled operation during a long-term period of a high-rate partial nitrification activated sludge system

“…Moreover, the lower the SRT, the higher are the specific nitrifying rates [18][19][20]. However, the activated sludge systems working at low SRT have a limited treatment capacity due to the low biomass concentration that can be achieved and it was reported that the SHARON process could be limited by this restriction [21]. The way to increase the biomass concentration and, consequently, the treatment capacity is working with biomass retention, i.e.…”

Removal of high concentration ammonia from wastewater by a combination of partial nitrification and anammox treatment

“…Therefore, an effective treatment process for nitrogen removal is desired. The anaerobic ammonia oxidation (Anammox) process, which involves simultaneous conversion of ammonium and nitrite into nitrogen gas under an anaerobic condition, has recently been attracting attention [4][5][6]. This is because it consumes less energy, produces less sludge and requires fewer carbon sources for denitrification as compared to the conventional nitrification and denitrification process [7].…”