Startup of a Partial Nitritation‐Anammox MBBR and the Implementation of pH‐Based Aeration Control

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This study evaluated startup strategies for mainstream polishing anammox moving bed biofilm reactors (MBBRs) without anammox bacterial (AMX) biomass inoculation. Two types of startups were tested: anammox only (no external carbon addition) and partial denitrification/anammox (PdNA) with glycerol addition. Reactors were started with either virgin carriers or carriers with a preliminary biofilm from a mainstream aerobic integrated fixed‐film activated sludge (IFAS) process. Three pilot‐scale startups were completed under the following conditions: anammox‐only with preliminary biofilm carriers, PdNA with preliminary biofilm carriers, and PdNA with virgin carriers. AMX presence was confirmed via quantitative polymerase chain reaction (qPCR) after 57, 57, and 77 days, respectively. Prior to AMX detection, average influent concentrations of ammonia and nitrite ranged from 1.7–2.7 mg/L and 0.98–1.8 mg/L, respectively. This study demonstrated that AMX can be grown on carriers without AMX seeding under mainstream conditions (temperature 17–29°C, low ammonia and nitrite), regardless of whether nitrite came from upstream or partial denitrification within the reactor. This study also showed that using preliminary biofilm carriers can decrease startup time by approximately 1 month. These results address critical questions for moving mainstream anammox processes to full‐scale implementation, and suggest that PdNA MBBRs are feasible and sustainable for full‐scale ammonia, nitrate, and nitrite polishing to meet stringent total nitrogen requirements. Practitioner Points This research will help utilities develop methods for starting up mainstream anammox MBBRs without the barrier of anammox biomass seeding. Preliminary biofilm carriers accelerated startup time in a PdNA MBBR, but a virgin carrier reactor started up in a similar timeframe, contrary to expectations. Also, contrary to expectations, high concentrations of ammonia and nitrite are not necessary for startup of an anammox or PdNA MBBR.

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Amx Activity Never Reached a Maximummentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Startup strategies for mainstream anammox polishing in moving bed biofilm reactors

Schoepflin

Justin

Long

et al. 2022

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“…As shown in Figure d,

Δ {NO}_{2}^{-} - N / Δ {NH}_{4}^{+} - N

and

Δ {NO}_{3}^{-} - N / Δ {NH}_{4}^{+} - N

were investigated. The theoretical stoichiometric ratios of

Δ {NO}_{2}^{-} - N / Δ {NH}_{4}^{+} - N

and

Δ {NO}_{3}^{-} - N / Δ {NH}_{4}^{+} - N

were 1.32 and 0.26 in anammox process, respectively (Klaus et al, ). In this work,

Δ {NO}_{2}^{-} - N / Δ {NH}_{4}^{+} - N

increased with trehalose addition, while

Δ {NO}_{3}^{-} - N / Δ {NH}_{4}^{+} - N

decreased.…”

Section: Resultsmentioning

confidence: 99%

Long‐term nitrogen removal performance and kinetics of anaerobic ammonia oxidation bacteria treating nitrogen‐rich saline wastewater with trehalose addition

Bai

et al. 2019

A sequencing batch reactor was used to study long-term nitrogen removal performance of anaerobic ammonia oxidation bacteria (AnAOB) with trehalose addition treating nitrogen-rich saline wastewater. The operating temperature was controlled at 35 ± 0.5°C with influent pH of 7.5 ± 0.1. Trehalose played a significant role in enhancing long-term nitrogen removal performance. When trehalose was 0.1, 0.2, and 0.3 mM, ammonia removal efficiency (ARE) increased by 4.9%, 16.2%, and 32.4%, and nitrite removal efficiency (NRE) improved by 7.5%, 27.9%, and 42.2%, respectively. Optimal ARE and NRE were 92.4% and 97.4% achieved at 0.35 mM trehalose. Moreover, NO − 2 − N was removed completely within 2 hr at high trehalose content due to the synergistic effect resulting from AnAOB and heterotrophic denitrifying bacteria.The remodified Logistic model and modified Gompertz model were suitable for describing nitrogen removal in an operating cycle with trehalose addition. Fitted ARE max values were consistent with experimental values. Appropriate trehalose addition could shorten the response time of AnAOB coping with hazardous environment stress. Lag time was within 1 hr and the minimal fitted λ value got close to 0 achieved at 0.15 mM trehalose. • Practitioner points• Trehalose enhanced nitrogen removal of AnAOB in saline wastewater treatment.• Optimal ARE and NRE were 92.4% and 97.4% achieved at 0.35 mM trehalose. • Remodified Logistic and Gompertz models can analyze nitrogen removal with trehalose. • Appropriate trehalose can shorten response time of AnAOB coping with salt stress.

Comparing methanol and glycerol as carbon sources for mainstream partial denitrification/anammox in an IFAS process

Bachmann,

Parsons,

Klaus

et al. 2024

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This study explored the implementation of mainstream partial denitrification with anammox (PdNA) in the second anoxic zone of a wastewater treatment process in an integrated fixed film activated sludge (IFAS) configuration. A pilot study was conducted to compare the use of methanol and glycerol as external carbon sources for an IFAS PdNA startup, with a goal to optimize nitrogen removal while minimizing carbon usage. The study also investigated the establishment of anammox bacteria on virgin carriers in IFAS reactors without the use of seeding, and it is the first IFAS PdNA startup to use methanol as an external carbon source. The establishment of anammox bacteria was confirmed in both reactors 102 days after startup. Although the glycerol‐fed reactor achieved a higher steady‐state maximum ammonia removal rate because of anammox bacteria (1.6 ± 0.3 g/m2/day) in comparison with the methanol‐fed reactor (1.2 ± 0.2 g/m2/day), both the glycerol‐ and methanol‐fed reactors achieved similar average in situ ammonia removal rates of 0.39 ± 0.2 g/m2/day and 0.40 ± 0.2 g/m2/day, respectively. Additionally, when the upstream ammonia versus NOx (AvN) control system maintained an ideal ratio of 0.40–0.50 g/g, the methanol‐fed reactor attained a lower average effluent TIN concentration (3.50 ± 1.2 mg/L) than the glycerol‐fed reactor (4.43 ± 1.6 mg/L), which was prone to elevated nitrite concentrations in the effluent. Overall, this research highlights the potential for PdNA in IFAS configurations as an efficient and cost‐saving method for wastewater treatment, with methanol as a viable carbon source for the establishment of anammox bacteria.Practitioner Points Methanol is an effective external carbon source for an anammox startup that avoids the need for costly alternative carbon sources. The methanol‐fed reactor demonstrated higher TIN removal compared with the glycerol‐fed reactor because of less overproduction of nitrite. Anammox bacteria was established in an IFAS reactor without seeding and used internally stored carbon to reduce external carbon addition. Controlling the influent ammonia versus NOx (AvN) ratio between 0.40 and 0.50 g/g allowed for low and stable TIN effluent conditions.