Total inorganic nitrogen removal during the partial/complete nitrification for treating domestic wastewater: Removal pathways and main influencing factors

This bench-scale study investigated the nitrogen-removal capabilities of two different biological process configurations treating methanogenic-state landfill leachate containing up to 1200 mg N/L of ammonia. The first configuration was a pre-denitrification system known as the modified Ludzack-Ettinger (MLE) process. Large clarifier sludge recycle flows, set to yield clarifier recycle ratios of 7:1 and 8:1, were evaluated as a means to reduce effluent NOx concentrations. A pre- and post-denitrification system, known as the four-stage Bardenpho process, was the second configuration evaluated. The MLE systems (20 day aerobic solids retention time (SRT)) were capable of producing effluent containing about 50 mg N/L of ammonia and 200-235 mg N/L of total inorganic nitrogen (ammonia + NOx) when treating leachate containing approximately 1200 mg N/L of ammonia. In contrast, effluent from the four-stage Bardenpho system contained less than 1 mg N/L of ammonia and 15 mg N/L of NOx, when treating 1100 mg N/L ammonia leachate. An aerobic number 1 SRT of 20 days (total aerobic SRT approximately equal to 40 days) was used with aerobic number 1 and clarifier sludge recycle ratios of 4:1 and 3:1, respectively. The ammonia-removal potential of both systems was clearly demonstrated but each system also showed certain disadvantages, characteristic of each process.Key words: ammonia-N, anoxic denitrification, leachate treatment, nitrification, pre-denitrification.

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Nitrogen removal and microbial communities of a completely autotrophic nitrogen removal over nitrite (CANON) sequencing batch biofilm reactor (SBBR) at different inorganic carbon (IC) concentrations

Water Science & Technology ◽

10.2166/wst.2020.203 ◽

2020 ◽

Vol 81 (5) ◽

pp. 1071-1079

Author(s):

Caimeng Wang ◽

Lirong Lei ◽

Fangrui Cai ◽

Youming Li

Keyword(s):

Nitrogen Removal ◽

Inorganic Nitrogen ◽

Biofilm Reactor ◽

Anammox Bacteria ◽

Ammonium Oxidation ◽

Sequencing Batch Biofilm Reactor ◽

Microbial Analysis ◽

Total Inorganic Nitrogen ◽

Canon Process ◽

Autotrophic Nitrogen Removal

Abstract In this study, the completely autotrophic nitrogen removal over nitrite (CANON) process was initiated in a sequencing batch biofilm reactor (SBBR). Then the reactor was operated under different IC/N ratios. The total inorganic nitrogen removal efficiency (TINRE) at IC/N ratios of 0.75, 1.0, 1.25, 1.5 and 2.0 were 37.0 ± 11.0%, 58.9 ± 10.2%, 73.9 ± 3.2%, 73.6 ± 1.8% and 72.6 ± 2.0%, respectively. The suitable range of IC/N ratio in this research is 1.25–2.0. The poor nitrogen removal performance at IC/N ratio of 0.75 was due to the lack of growth substrate for AnAOB and low pH simultaneously; at IC/N ratio of 1.0 this was because the substrate concentration was insufficient for fully recovering the AnAOB activities. Microbial analysis indicated that Nitrosomonas, Nitrospira and Candidatus Brocadia were the main ammonium oxidation bacteria (AOB), nitrite oxidation bacteria (NOB) and anammox bacteria (AnAOB), respectively. In addition, at IC ratios of 1.25 or higher, denitrification was promoted with the rise of IC/N ratio, which might be because the change of IC concentrations caused cell lysis of microorganisms and provided organic matter for denitrification.

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Coupling autotrophic denitrification with partial nitritation-anammox (PNA) for efficient total inorganic nitrogen removal

Bioresource Technology ◽

10.1016/j.biortech.2017.06.130 ◽

2017 ◽

Vol 243 ◽

pp. 700-707 ◽

Cited By ~ 18

Author(s):

Sunayna Dasgupta ◽

Sha Wu ◽

Ramesh Goel

Keyword(s):

Nitrogen Removal ◽

Inorganic Nitrogen ◽

Autotrophic Denitrification ◽

Partial Nitritation ◽

Total Inorganic Nitrogen

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Effect of cycle time and airflow in biological nitrogen removal from poultry slaughterhouse wastewater using sequencing batch reactor

Engenharia Agrícola ◽

10.1590/1809-4430-eng.agric.v35n3p567-577/2015 ◽

2015 ◽

Vol 35 (3) ◽

pp. 567-577 ◽

Cited By ~ 2

Author(s):

Carla L. Lopes ◽

Juliana B. R. Mees ◽

Luciane Sene ◽

Karina Q. de Carvalho ◽

Divair Christ ◽

...

Keyword(s):

Nitrogen Removal ◽

Cycle Time ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Inorganic Nitrogen ◽

Slaughterhouse Wastewater ◽

Whole Process ◽

Working Volume ◽

Total Inorganic Nitrogen ◽

Nitrification And Denitrification

This study aimed to evaluate the influence of airflow (0.25, 0.50 and 0.75 L.L-1.min-1) and cycle time (10.45 h, 14.25 h and 17.35 h) on a sequencing batch reactor (SBR) performance in promoting nitrification and denitrification of poultry slaughterhouse wastewater. The operational stages included feeding, aerobic and anoxic reactions, sedimentation and discharge. SBR was operated in a laboratory scale with a working volume of 4 L, keeping 25% of biomass retained inside the reactor as inoculum for the next batch. In the anoxic stage, C: N ratio was maintained between 5 and 6 by adding cassava starch wastewater. A factorial design (22) with five repetitions was designed at the central point to evaluate the influence of cycle time and airflow on total inorganic nitrogen removal (N-NH4++N-NO2-+N-NO3-) and in the whole process (nitrification and denitrification). The highest total inorganic nitrogen removal (93.3%) was observed for airflow of 0.25 L.L-1.min‑1 and a cycle time of 14.25 h. At the end of the experiment, the sludge inside the reactor was characterized by fluorescent in situ hybridization (FISH), indicating the presence of ammonia and nitrite oxidizing bacteria.

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Use of Constructed Wetlands to Treat Domestic Wastewater, City of Arcata, California

Water Science & Technology ◽

10.2166/wst.1992.0606 ◽

1992 ◽

Vol 26 (7-8) ◽

pp. 1625-1637 ◽

Cited By ~ 29

Author(s):

R. A. Gearheart

Keyword(s):

Constructed Wetlands ◽

Fecal Coliform ◽

Inorganic Nitrogen ◽

Domestic Wastewater ◽

Growing Season ◽

Water Quality Standards ◽

Oxidation Pond ◽

Nitrogen Levels ◽

Total Inorganic Nitrogen ◽

Tin Removal

This paper summarizes 10 years of experience applying oxidation pond effluent to constructed wetlands in Arcata, California. The first five years (1980-1986) was spent experimenting with 6×66 metre constructed wetland mesocosm. The second five years involved fullscale analysis of 2.8 hectares and 12 hectares effluent receiving marshes. Experience to date has verified the capability of constructed wetlands to reliably and effectively meet advanced secondary water quality standards. Effluent BOD and suspended solids concentrations of 30 and 30 mg/l respectively can be met ninety percent of the time with weekly samples; fecal coliform levels of 20 CFU/100 can be met 90 percent of the time. Total inorganic nitrogen levels of 5 can be met in the growing season at 12 mg/l in the non-growing season. Design criteriaaregiven for BOD, SS, coliform, and TIN removal for a temperature range of 6 to 20°C. Experience gained to date on the construction details, vegetation planting, and operational consideration is also summarized in the paper.

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Response of simultaneous nitrification-denitrification to DO increments in continuously aerated biofilm reactors for aquaculture wastewater treatment

Water Practice & Technology ◽

10.2166/wpt.2021.062 ◽

2021 ◽

Author(s):

Shiyang Zhang ◽

Jing Chen ◽

Julin Yuan ◽

Guangjun Wang

Keyword(s):

Inorganic Nitrogen ◽

High Strength ◽

Biofilm Reactors ◽

A Value ◽

Total Inorganic Nitrogen ◽

Do Concentration ◽

Aquaculture Wastewater ◽

Polyphosphate Accumulating Organisms ◽

Intensive Aquaculture ◽

Complete Nitrification

Abstract Intensive aquaculture usually produces large volumes of nutrient-rich wastewater, which is essential to treat to avoid eutrophication. This study aimed to evaluate the performance of five, continuously aerated, biofilm reactors treating simulated, high-strength, aquaculture wastewater under different dissolved oxygen (DO) levels, and the effects of DO increments on simultaneous nitrification-denitrification (SND). Continuous aeration was beneficial to complete nitrification. Total inorganic nitrogen (TIN), principally ammonium, was mainly removed by SND. The SND rate response to different DO levels was fitted well by the power function of y = 54.81 + 371.58/(1 − 0.16*x)^(−1/0.24) (R2 = 0.897, P = 0.000). When the TIN was removed completely, the optimal SND rate was defined and corresponded to a value of 121.8%. Accordingly, the optimal DO concentration was calculated as 2.10 mg/L, close to the actual level of 1.83 mg/L, at which the highest proportional removals of total nitrogen (58.0%) and TIN (57.3%) were obtained. Phosphorus was also removed by denitrifying polyphosphate-accumulating organisms.

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