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- Cema, Grzegorz, et al.
(författare)
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Nitrogen removal rates at a technical-scale pilot plant with the one-stage partial nitritation/Anammox process.
- 2006
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Ingår i: Water Science and Technology. - : IWA Publishing. - 0273-1223 .- 1996-9732. ; 54:8, s. 209-217
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Tidskriftsartikel (refereegranskat)abstract
- Traditional nitrification/denitrification is not suitable for nitrogen removal when wastewater contains high concentrations of ammonium nitrogen and low concentrations of biodegradable carbon. Recently, a deammonification process was developed and proposed as a new technology for treatment of such streams. This process relies on a stable interaction between aerobic bacteria Nitrosomonas, that accomplish partial nitritation and anaerobic bacteria Planctomycetales, which conduct the Anammox reaction. Simultaneous performance of these two processes can lead to a complete autotrophic nitrogen removal in one single reactor. The experiments where nitrogen was removed in one reactor were performed at a technical-scale moving-bed pilot plant, filled with Kaldnes rings and supplied with supernatant after dewatering of digested sludge. It was found that a nitrogen removal rate obtained at the pilot plant was 1.9 g m(-2) d(-1). Parallel to the pilot plant run, a series of batch tests were carried out under anoxic and aerobic conditions. Within the batch tests, where the pilot plant's conditions were simulated, removal rates reached up to 3g N m(-2) d(-1). Moreover, the batch tests with inhibition of Nitrosomonas showed that only the Anammox bacteria (not anoxic removal by Nitrosomonas) are responsible for nitrogen removal.
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- Gut, Luiza, et al.
(författare)
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Combined partial nitritation/Anammox system for treatment of digester supernatant
- 2006
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Ingår i: Water Science and Technology. - : IWA Publishing. - 0273-1223 .- 1996-9732. ; 53:12, s. 149-159
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Tidskriftsartikel (refereegranskat)abstract
- One-year (2004) comprehensive investigations in a semi-industrial pilot plant (5 m(3)) were carried out with the aim of assessing the influence of operational parameters on the partial nitritation/Anammox system performance. In the system designed as a moving-bed biofilm reactor, the influent nitrogen load to the Anammox reactor was progressively increased and a stable Anammox bacterial culture was obtained. Interaction between subsequent, aerobic and anaerobic conditions in the partial nitritation and Anammox reactors, respectively, granted conditions to remove nitrogen through the nitrite route. It implies that the oxygen supply can be limited to a high extent. A control strategy for the partial nitritation step relied on concomitant adjustment of the air supply with a variable influent nitrogen load, which can be monitored by both pH and conductivity measurements. In the Anammox reactor, an influent nitrite-to-ammonium ratio plays a vital role in obtaining efficient nitrogen removal. During the 1-year experimental period, the Anammox reactor was operated steadily and average nitrogen removal efficiency was 84% with 97% as the maximum value.
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- Plaza, Elzbieta, et al.
(författare)
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Directions in Swedish research on wastewater handling with respect to energy and resource utilization
- 2009
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Ingår i: Proceedings of the 1st International Congress.
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Konferensbidrag (refereegranskat)abstract
- A change in research priorities has gradually occurred in many European countries in order tocomply with sustainability principles. At present new technologies should meet requirements of sustainabledevelopment and multi-disciplinary approach is applied. Research activities in Sweden related towastewater handling have been focused on optimizing the existing systems and the development of newmethods with respect to energy and resources utilization.The article presents recent results from research on biological nitrogen removal with Anammoxprocess application. This new nitrogen conversion pathway can be applied for treatment of ammonium richwastewater, including leachates from landfills and supernatants from dewatering of digested sludge withthe purpose to decrease nitrogen discharges into waters. The introduction of deammonification processbased on nitritation/Anammox can reduce the costs of plant operation due to less aeration and no externalsource of carbon demand in comparison to the traditional nitrification/denitrification.Pharmaceuticals found in wastewater are passing through the wastewater treatment plant untreated andcause environmental problems. The application of membrane bioreactor system followed by granular activatedcarbon filtration has been studied as the efficient technology for removal of pharmaceutical compounds.The growing quantities of sludge from wastewater treatment plants and stringent restrictions onlandfilling and on agricultural use of sludge have gained research on sludge fractionation, product recoveryand separation of toxic substances. Phosphate release and recovery from treated sewage sludge has beeninvestigated and experiments were performed on sludge residue from supercritical water oxidation, ashfrom incineration and dried sludge at different temperatures. In the article future main research areas inwastewater handling planned to be investigated in Sweden are also specified.
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- Szatkowska, Beata, et al.
(författare)
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A one-stage system with partial nitritation and Anammox processes in the moving-bed biofilm reactor
- 2007
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Ingår i: Water Science and Technology. - : IWA Publishing. - 0273-1223 .- 1996-9732. ; 55:8-9, s. 19-26
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Tidskriftsartikel (refereegranskat)abstract
- The ability of bacterial cultures to create biofilm brings a possibility to enhance biological 0 0 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 m(3)) at the Himmerfjarden 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 to its relationship with conductivity was found. The nitrogen removal rate for the whole period oscillated around 1.5g N m(-2) d(-1) with a maximum value equal to 1.9 g N m(-2) d(-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 4, conditions and addition of nitrite. The highest nitrogen removal rate (5.2 g N m(-2) d(-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.
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