scholarly journals Achieving Partial Nitritation in Anammox Start-Up Environment

Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 229
Author(s):  
Sabin Pathak ◽  
Shuai Wang ◽  
Eshetu Janka
Keyword(s):  
Accumulation Rate ◽  
Nitrogen Compound ◽  
Biofilm Reactor ◽  
Free Ammonia ◽  
Synthetic Wastewater ◽  
Nitrite Accumulation ◽  
Intermittent Aeration ◽  
Partial Nitritation ◽  
One Stage ◽  
Start Up

Removing ammonium via the partial nitritation anammox (PNA) process has been widely applied because of its cost and energy effectiveness. However, the first stage of PNA, partial nitritation, is hard to implement practically due to the challenging suppression of nitrate oxidizing bacteria (NOB) and should be achieved in the anammox environment to extend it to one stage PNA. Hence, this article evaluates different techniques, such as the combination of low dissolve oxygen (DO) and high free ammonia (FA), and the intermittent aeration cycle to achieve partial nitritation in an anammox start-up environment. For this purpose, a 10.5 L lab-scale moving bed biofilm reactor was set up and fed with synthetic wastewater and the transformation of influent ammonium into nitrate and nitrite was measured. The results showed that, despite applying low DO and higher free ammonia than the inhibition range of NOB, the nitrate production rate (NPR) was consistently higher than the nitrite accumulation rate (NAR), signifying no sufficient NOB suppression, partial nitritation under continuous aeration and up to a 0.27 gN/m2.d surface ammonium loading rate (SALR). Higher SALR than 0.27 gN/m2.d could result in partial nitritation since nitrogen compounds transformation was closer to partial nitritation when the reactor was subjected to 0.27 gN/m2.d rather than 0.14 gN/m2.d. Lifting up the SALR, on the other hand, results in a bad anammox environment and cannot prolong it to one-stage PNA. An intermittent aeration cycle with four different cycle lengths sets, obtained by monitoring nitrogen compound transformation, was, therefore, applied to the reactor. The relatively shorter aerobic length of 10 min ON and 30 OFF intermittent aeration cycle with 0.5 mg/L aerated DO was successful in achieving the partial nitritation with NPR, NAR, and ammonium removal efficiency (ARE) values of 17%, 78%, and 37%, respectively, showing that shorter aerated length suppresses NOB to a high degree due to less available time for NOB after oxygen starvation.

Study on Achievement and Temperature Influence of Shortcut Nitrification in Sequencing Biofilm Batch Reactor

2014 ◽  
Vol 955-959 ◽  
pp. 3389-3392
Author(s):  
Li Cheng Zhang ◽  
Wei Dang ◽  
Jie Li ◽  
Jun Sui
Keyword(s):  
Accumulation Rate ◽  
Batch Reactor ◽  
Biofilm Reactor ◽  
Nitrite Accumulation ◽  
Ammonia Oxidizing Bacteria ◽  
Temperature Influence ◽  
Intermittent Aeration ◽  
Urban Sewage ◽  
Sequencing Batch Biofilm Reactor ◽  
Start Up

The intermittent aeration strategy was applied to the sequencing batch biofilm reactor (SBBR) for the enhanced treatment of urban sewage. Ammonia oxidizing bacteria was cultivated by inoculation. After 25 days cultivation shortcut nitrification was successfully achieved and nitrite accumulation rate could be up to 93%. In the start-up phase of shortcut nitrification, intermittent aeration could increase production of nitrite and promote the enrichment of ammonia oxidizing bacteria. It was concluded that temperature could affect nitrite accumulation. When temperature is in 25~35°C, the nitrite accumulation rate could be up to 90%.

scholarly journals Rapid Start-Up of the Aerobic Granular Reactor under Low Temperature and the Nutriment Removal Performance of Granules with Different Particle Sizes

Water ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 3590
Author(s):  
Dongbo Liang ◽  
Jun Li ◽  
Zhaoming Zheng ◽  
Jing Zhang ◽  
Yaodong Wu ◽  
...  
Keyword(s):  
Low Temperature ◽  
Accumulation Rate ◽  
Removal Rate ◽  
Batch Reactor ◽  
Synthetic Wastewater ◽  
Aerobic Granular Sludge ◽  
Nitrite Accumulation ◽  
Stable Operation ◽  
N Removal ◽  
Start Up

The start-up of the aerobic granular sludge (AGS) process under low temperature is challenging. In this study, the sequencing batch reactor (SBR) was fed with synthetic wastewater and the temperature was controlled at 15 ℃. The main components in the synthetic wastewater were sodium acetate and ammonium chloride. The influent chemical oxygen demand (COD) and NH4+-N concentrations were 300 and 60 mg/L, respectively. The AGS was successfully cultivated in 60 days by gradually shortening the settling time. During the stable operation stage (61–100 d), the average effluent COD, NH4+-N, NO2−-N, and NO3−-N concentrations were 47.2, 1.0, 47.2, and 5.1 mg/L, respectively. Meanwhile, the nitrite accumulation rate (NAR) reached 90.6%. Batch test showed that the smaller AGS had higher NH4+-N removal rate while the larger AGS performed higher NAR. The NH4+-N removal rates of R1 (1.0–2.0 mm), R2 (2.0–3.0 mm), and R3 (>3 mm) granules were 0.85, 0.61, and 0.45 g N/(kg VSS·h), respectively. Meanwhile, the NAR of R1, R2, and R3 were 36.2%, 77.2%, and 94.9%, respectively. The obtained results could provide important guidance for the cultivation of AGS in low-temperature wastewater treatment.

scholarly journals Aggregate Size and Architecture Determine Microbial Activity Balance for One-Stage Partial Nitritation and Anammox

2009 ◽  
Vol 76 (3) ◽  
pp. 900-909 ◽  
Author(s):  
Siegfried E. Vlaeminck ◽  
Akihiko Terada ◽  
Barth F. Smets ◽  
Haydée De Clippeleir ◽  
Thomas Schaubroeck ◽  
...  
Keyword(s):  
Extracellular Polymeric Substances ◽  
Accumulation Rate ◽  
Aggregate Size ◽  
Nitrite Accumulation ◽  
Partial Nitritation ◽  
Nitrite Production ◽  
Hydrodynamic Shear ◽  
Aggregate Morphology ◽  
Aeration Conditions ◽  
Species Specific

ABSTRACT Aerobic ammonium-oxidizing bacteria (AerAOB) and anoxic ammonium-oxidizing bacteria (AnAOB) cooperate in partial nitritation/anammox systems to remove ammonium from wastewater. In this process, large granular microbial aggregates enhance the performance, but little is known about granulation so far. In this study, three suspended-growth oxygen-limited autotrophic nitrification-denitrification (OLAND) reactors with different inoculation and operation (mixing and aeration) conditions, designated reactors A, B, and C, were used. The test objectives were (i) to quantify the AerAOB and AnAOB abundance and the activity balance for the different aggregate sizes and (ii) to relate aggregate morphology, size distribution, and architecture putatively to the inoculation and operation of the three reactors. A nitrite accumulation rate ratio (NARR) was defined as the net aerobic nitrite production rate divided by the anoxic nitrite consumption rate. The smallest reactor A, B, and C aggregates were nitrite sources (NARR, >1.7). Large reactor A and C aggregates were granules capable of autonomous nitrogen removal (NARR, 0.6 to 1.1) with internal AnAOB zones surrounded by an AerAOB rim. Around 50% of the autotrophic space in these granules consisted of AerAOB- and AnAOB-specific extracellular polymeric substances. Large reactor B aggregates were thin film-like nitrite sinks (NARR, <0.5) in which AnAOB were not shielded by an AerAOB layer. Voids and channels occupied 13 to 17% of the anoxic zone of AnAOB-rich aggregates (reactors B and C). The hypothesized granulation pathways include granule replication by division and budding and are driven by growth and/or decay based on species-specific physiology and by hydrodynamic shear and mixing.

Nitritation of real sewage: start-up and maintenance by the side-stream heat-shock treatment

2019 ◽  
Vol 79 (4) ◽  
pp. 753-758 ◽  
Author(s):  
Jianfei Chen ◽  
Shujun Zhang ◽  
Xiaoyu Han ◽  
Liang Zhang ◽  
Yongzhen Peng
Keyword(s):  
Heat Shock ◽  
Accumulation Rate ◽  
Batch Reactor ◽  
Shock Treatment ◽  
Nitrite Accumulation ◽  
Heat Shock Treatment ◽  
Term Operation ◽  
Side Stream ◽  
Start Up

Abstract In this study, the side-stream heat-shock treatment was used to start up and maintain the nitritation of real sewage. Complete nitrification was obtained when the real sewage was treated in a sequencing batch reactor (SBR). Then, about 50% of the mixed sludge was collected from the SBR and treated with the heat-shock treatment at 60 °C for 40 min in another reactor every 2 weeks. After providing the heat-shock treatment for four times, the effluent nitrate in the SBR gradually decreased from 22.5 to 3.2 mg/L, while the nitrite accumulation rate increased from 4.4% to 81.8%, indicating a successful start-up of nitritation. Further, the sewage nitritation was stable with the regular side-steam heat-shock treatment for 91 days, and the ammonium removal efficiency of 80.6% and nitrite accumulation rate of 91.2% were achieved. This study suggests that the side-stream heat-shock treatment could be used to start up sewage nitritation and maintain stability for a long-term operation.

Combination of photo-Fenton and biological SBBR processes for sulfamethoxazole remediation

2008 ◽  
Vol 58 (9) ◽  
pp. 1707-1713 ◽  
Author(s):  
O. González ◽  
M. Esplugas ◽  
C. Sans ◽  
S. Esplugas
Keyword(s):  
Biological Treatment ◽  
Fenton Reaction ◽  
Biofilm Reactor ◽  
Synthetic Wastewater ◽  
Total N ◽  
Sequencing Batch Biofilm Reactor ◽  
N Removal ◽  
Start Up ◽  
C And N ◽  
Combined Strategy

A combined strategy of a photo-Fenton pretreatment followed by a Sequencing Batch Biofilm Reactor (SBBR) was evaluated for total C and N removal from a synthetic wastewater containing 200 mg L−1 of the antibiotic Sulfamethoxazole (SMX). Photo-Fenton reaction was performed with two different H2O2 concentrations (300 and 400 mg L−1) and 10 mg L−1 of Fe2 + . The pre-treated effluents with the antibiotic intermediates as sole carbon source, together with a nutrients solution, were used as feed for the biological reactor. The SBBR was operated under aerobic conditions to mineralize the organic carbon and the hydraulic retention time (HRT) was optimized down to 8 hours. Then, an anoxic denitrification stage of 24 hours of HRT was added right after the aerobic stage of the same duration in order to remove the NO3− generated along the chemical–biological treatment. TOC, COD and SMX concentrations together with O2 uptake rate (OUR) profiles were monitored in purpose of assessing the performance of the system. NO3−, NH4+ and total N concentrations were analyzed to find out the fate of N contained in the initial SMX molecule. A start up strategy resulted in the correct formation of a biofilm over the volcanic support. The total TOC removals achieved with the combination of the chemical and the biological processes were 75.7 and 87.7% for the low and the high H2O2 concentration pretreatments respectively. Practically all N present in the SMX solution was eliminated in the SBBR when the aerobic–anoxic strategy was used.

scholarly journals Start-up of a full-scale partial nitritation-anammox MBBR without inoculum at Klagshamn WWTP

2020 ◽  
Vol 81 (9) ◽  
pp. 2033-2042 ◽  
Author(s):  
Ivelina Dimitrova ◽  
Agnieszka Dabrowska ◽  
Sara Ekström
Keyword(s):  
Nitrogen Removal ◽  
Removal Rate ◽  
Treatment Plant ◽  
Full Scale ◽  
Biofilm Reactor ◽  
Operating Conditions ◽  
Ex Situ ◽  
Ammonium Oxidation ◽  
Partial Nitritation ◽  
Start Up

Abstract Partial nitritation and anaerobic ammonium oxidation (PNA) is a useful process for the treatment of nitrogen-rich centrate from the dewatering of anaerobically digested sludge. A one-stage PNA moving bed biofilm reactor (MBBR) was started up without inoculum at Klagshamn wastewater treatment plant, southern Sweden. The reactor was designed to treat up to 200 kgN d−1, and heated dilution water was used during start-up. The nitrogen removal was &gt;80% after 111 days of operation, and the nitrogen removal rate reached 1.8 gN m−2 d1 at 35 °C. The start-up period of the reactor was comparable to that of inoculated full-scale systems. The operating conditions of the system were found to be important, and online control of the free ammonia concentration played a crucial role. Ex situ batch activity tests were performed to evaluate process performance.

scholarly journals Nitrite Accumulation at Low Copper Concentration in a Submerged Partial Bionitrification Reactor

2021 ◽  
Vol 43 (6) ◽  
pp. 419-427
Author(s):  
Sukru Aslan ◽  
Burhanettin Gurbuz
Keyword(s):  
Loading Rate ◽  
Accumulation Rate ◽  
Removal Rate ◽  
Synthetic Wastewater ◽  
Flow Mode ◽  
Nitrite Accumulation ◽  
N Accumulation ◽  
Operational Conditions ◽  
Support Materials ◽  
N Removal

Objectives : Effects of various Cu2+ concentrations in the synthetic wastewater on nitrite accumulation was investigated in a submerged partial biofilter reactor (SPBNR).Methods : Experiments were carried out at the constant operational conditions (T=35℃; pH=9.0 and DO=2.0 mg O2/L) by varying the concentrations between 5-50 mg Cu2+/L. The SPBNR, which was operated in an upward flow mode, set-up consisted of a cylindrical stainless steel. The support materials filling ratio was about 23% of the total reactor volume. The SPBNR was inoculated with microorganism drawn from a batch experimental biological reactor operated about one month by using the synthetic wastewater composition.Results and Discussion : Before exposure to Cu2+, the highest loading rate of 1.3 g NH4-N/(m2.day) was determined under the operational conditions. Addition of 5 µg Cu2+/L into the waters promoted the activity of organisms and the loading rate achieved to 1.6 g NH4-N/(m2.day). At the control operational condition, the ratio of NO2-N/NOx-N was determined as 0.74, while the ratio increased to 0.78 at the Cu2+ concentration of 5 µg/L.Conclusions : Results indicated that the ammonium oxidizing bacteria (AOB) is more stimulated than the nitrite oxidizing bacteria (NOB) at the concentration of 5 µg Cu2+/L. However, approximately equal NH4-N removal rate (ANRR) and NO2-N accumulation rate (NiAR) losses indicated that the AOB and NOB are approximately equally effected at the inlet concentrations of 35 and 50 µg Cu2+/L.

Influence of seasonal temperature fluctuations on two different partial nitritation-anammox reactors treating mainstream municipal wastewater

2015 ◽  
Vol 72 (8) ◽  
pp. 1358-1363 ◽  
Author(s):  
Susanne Lackner ◽  
Samuel Welker ◽  
Eva M. Gilbert ◽  
Harald Horn
Keyword(s):  
Municipal Wastewater ◽  
Batch Reactor ◽  
High Energy ◽  
Biofilm Reactor ◽  
Ex Situ ◽  
Nitrite Accumulation ◽  
Seasonal Temperature ◽  
Partial Nitritation ◽  
Conversion Rates ◽  
Anammox Activity

Partial nitritation-anammox (PN-A) has gained increasing interest for municipal wastewater treatment in recent years due to its high energy-saving potential. Moving the PN-A technology from side- to mainstream exhibited a set of challenges. Conditions are quite different, with much lower ammonium concentrations and temperatures. Biomass retention becomes highly important due to the even lower growth rates. This study compared two laboratory-scale reactors, a sequencing batch reactor (SBR) and a moving bed biofilm reactor (MBBR), employing realistic seasonal temperature variations over a 1-year period. The results revealed that both systems had to face decreasing ammonium conversion rates and nitrite accumulation at temperatures lower than 12°C. The SBR did not recover from the loss in anammox activity even when the temperature increased again. The MBBR only showed a short nitrite peak and recovered its initial ammonium turnover when the temperature rose back to &gt;15°C. The SBR had higher biomass specific rates, indicating that suspended sludge is less diffusion-limited but also more susceptible to biomass wash-out. However, the MBBR showed the more stable performance also at low temperatures and managed to recover. Ex situ batch activity tests supported reactor operation data by providing additional insight with respect to specific biomass activities.

A one-stage system with partial nitritation and Anammox processes in the moving-bed biofilm reactor

2007 ◽  
Vol 55 (8-9) ◽  
pp. 19-26 ◽  
Author(s):  
B. Szatkowska ◽  
G. Cema ◽  
E. Plaza ◽  
J. Trela ◽  
B. Hultman
Keyword(s):  
Nitrogen Removal ◽  
Pilot Plant ◽  
Removal Rate ◽  
Biofilm Reactor ◽  
Waste Water Treatment Plant ◽  
Partial Nitritation ◽  
One Stage ◽  
Batch Tests ◽  
Stage System ◽  
Anammox Process

The ability of bacterial cultures to create biofilm brings a possibility to enhance biological wastewater treatment efficiency. Moreover, the ability of Anammox and Nitrosomonas species to grow within the same biofilm layer enabled a one-stage system for nitrogen removal to be designed. Such a system, with Kaldnes rings as carriers for biofilm growth, was tested in a technical pilot plant scale (2.1 m3) at the Himmerfjärden Waste Water Treatment Plant (WWTP) in the Stockholm region. The system was directly supplied with supernatant originating from dewatering of digested sludge containing high ammonium concentrations. Nearly 1-year of operational data showed that during the partial nitritation/Anammox process, alkalinity was utilised parallel to ammonium removal. The process resulted in a small pH drop, and its relationship with conductivity was found. The nitrogen removal rate for the whole period oscillated around 1.5 g N m−2d−1 with a maximum value equal to 1.9 g N m−2d−1. Parallel to the pilot plant experiment, a series of batch tests were run to investigate the influence on removal rates of different dissolved oxygen conditions and addition of nitrite. The highest nitrogen removal rate (5.2 g N m−2d−1) in batch tests was obtained when the Anammox process was stimulated by the addition of nitrite. In the simultaneous partial nitritation and Anammox process, the partial nitritation was the rate-limiting step.

Sign in / Sign up

Export Citation Format

Share Document