Pilot scale studies on nitritation-anammox process for mainstream wastewater at low temperature

Abstract

Process of partial nitritation-anammox for mainstream wastewater at low temperature was run in a pilot scale moving bed biofilm reactor (MBBR) system for about 300 days. The biofilm history in the reactor was about 3 years of growth at low temperature (down to 10 °C). The goal of the studies presented in this paper was to achieve effective partial nitritation-anammox process. Influence of nitrogen loading rate, hydraulic retention time, aeration strategy (continuous versus intermittent) and sludge recirculation (integrated fixed-film activated sludge (IFAS) mode) on deammonification process' efficiency and microbial activity in the examined system was tested. It was found that the sole intermittent aeration strategy is not a sufficient method for successful suppression of nitrite oxidizing bacteria in MBBR. The best performance of the process was achieved in IFAS mode. The highest recorded capacity of ammonia oxidizing bacteria and anammox bacteria in biofilm was 1.4 gN/m(2)d and 0.5 gN/m(2)d, respectively, reaching 51% in nitrogen removal efficiency.

Nitrate residual as a key parameter to efficiently control partial denitrification coupling with anammox

“…In addition, maintaining an ammonium residual of 1–2 mg /L for suspended sludge (Regmi et al, ) or up to 5 mg /L for granular sludge (Poot, Hoekstra, Geleijnse, Loosdrecht, & Pérez, ) was needed to suppress NOB as well as provide kinetic advantage for AerAOB and AnAOB in mainstream conditions. This can be problematic when stringent nitrogen limits need to be met, especially given that effluent quality in reported systems has been mostly above 4 mg N/L (Cao, Loosdrecht, & Daigger, ; Gilbert et al, ; Han, Vlaeminck, et al, ; Laureni et al, ; Lotti et al, ; Trojanowicz, Plaza, & Trela, ).…”

Landfill Leachate Treatment Using a Combination of Heterotrophic Denitrification and Partial Nitritation in a Single Sequencing Batch Reactor

“…It should be stressed that differences in the reactor configuration and in aeration strategy as well as in the wastewater type might result in different threshold levels for successful partial nitritation. The DO control is a widely used strategy to maintain nitritation, because the DO could be easily controlled through the adjustment of aeration [9]. In fact, the mechanism behind both the DO and the airflow rate control is the same, namely the air supply must match influent loading, including nitrogen and organic loadings [44].…”

“…In the last decade, new techniques that utilize a combination of partial nitritation (PN) and anaerobic ammonium oxidation (anammox) [7][8][9], either in twostage systems or in the single reactor [10][11][12], have been developed to treat ammonium-rich wastewater more effectively [13,14]. Since most biodegradable organic fractions could negatively affect anammox performance [15], the one-stage PN/anammox process may only be applicable to wastewater with high levels of ammonium but lacking biodegradable organic carbon.…”

Thermal Effects

“…Partial nitritation-ANAMMOX process was applied for the wastewater treatment at low temperature (down to 10 °C) in a pilot scale MBBR system with biofilm growing at low temperature for 3 years. The highest capacity of ammonia oxidizing bacteria (AOB) and anammox bacteria (AB) in the system was 1.4 g N/m 2 d and 0.5 g N/m 2 d, respectively, and 51% nitrogen was removed (Trojanowicz et al 2016). Applying PN/A process to anaerobically pretreated municipal wastewater at a normal temperature of 22 °C was evaluated by Kouba et al (2016).…”