| 1. |
- Cema, Grzegorz, et al.
(författare)
-
A one-stage system with partial nitritation and Anammox processes in Rotating Biological Contactor (RBC) for treating landfill leachate
-
Ingår i: Journal of Hazardous Materials. - 0304-3894 .- 1873-3336.
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- One of the major aspects associated with landfilling of solid wastes is related to the discharge of leachate into environment. Leachates with high ammonium nitrogen content are generally difficult to effective treat in conventional biological treatment processes. Therefore, it brings a requirement of developing new processes and technologies. Additionally, treatment procedures must consider small flow rates of leachate. The Rotating Biological Contactor (RBC) is a good example of technology for treatment such wastewaters, because of its excellent shock and toxic loading capabilities, simple process control and low energy requirements. The main objective of the presented research was to investigate a simultaneous partial nitritation/Anammox process in the rotating biological contactor. For this purpose, the lab-scale reactor was fed with real landfill leachate from two municipal landfill sites in Gliwice and Zabrze (Poland). The reactor was highly loaded up to 7 g N m-2d-1 and it was possible to obtain the maximum inorganic nitrogen removal rate of 6.2 g N m-2d-1. Achieved results proved the possibility of efficient inorganic nitrogen removal by means of partial nitritation/ Anammox process in the temperature around 20°C.
|
|
| 2. |
- Cema, Grzegorz, 1979-
(författare)
-
Comparative study on different Anammox systems
- 2009
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The legal requirements for wastewater discharge into environment, especially to zones exposed to eutrophication, lately became stricter. Nowadays wastewater treatment plants have to manage with the new rules and assure better biogenic elements’ removal, in comparison with the past. There are some well-known methods of diminishing concentrations of these compounds, but they are ineffective in case of nitrogen-rich streams, as landfill leachate or reject waters from dewatering of digested sludge. This wastewater disturbs conventional processes of nitrification-denitrification and raise necessity of building bigger tanks. The partial nitritation followed by Anaerobic Ammonium Oxidation (Anammox) process appear to be an excellent alternative for traditional nitrification/denitrification. The process was investigated in three different reactors – Membrane Bioreactor (MBR), Moving Bed Biofilm Reactor (MBBR) and Rotating Biological Contactor (RBC). The process was evaluated in two options: as a two-stage process performed in two separate reactors and as a one-stage process. The two-step process, in spite of very low nitrogen removal rates, assured very high nitrogen removal efficiency, exceeding even 90% in case of the MBBR. However, obtained results revealed that the one-step system is a better option than the two-step system, no matter, what kind of nitrogen-rich stream is taken into consideration. Moreover, the one-step process was much less complicated in operation. Performed research confirmed a hypothesis, that the oxygen concentration in the bulk liquid and the nitrite production rate are the limiting factors for the Anammox reaction in a single reactor. In order to make a quick and simple determination of bacteria activity, the Oxygen Uptake Rate (OUR) tests were shown as an excellent tool for evaluation of the current bacteria activity reliably, and without a need of using expensive reagents. It was also shown, that partial nitritation/Anammox process, could be successfully applied at temperatures much lower than the optimum value. Performed Fluorescent in situ Hybridization (FISH) analyses, proved that the Anammox bacteria were mainly responsible for the nitrogen removal process.
|
|
| 3. |
- Cema, Grzegorz, et al.
(författare)
-
Nitrogen removal rates at a technical-scale pilot plant with the one-stage partial nitritation/Anammox process.
- 2006
-
Ingår i: Water Science and Technology. - : IWA Publishing. - 0273-1223 .- 1996-9732. ; 54:8, s. 209-217
-
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.
|
|
| 4. |
- Gut, Luiza, 1979-
(författare)
-
Assessment of a partial nitritation/Anammox system for nitrogen removal
- 2006
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis evaluates the performance of a deammonification system designed as a two-step tech-nology consisting of an initial partial nitritation followed by an Anammox process. Operation of a technical-scale pilot plant at the Himmerfjärden Wastewater Treatment Plant (Grödinge, Swe-den) has been assessed. Oxygen Uptake Rate (OUR) to evaluate the respiration activity of nitrifi-ers in the system and batch tests to assess reaction rates have also been applied in the study. It was found that the total inorganic nitrogen elimination strongly depended on the nitrite-to-ammonium ratio in the influent to the Anammox reactor, which was correlated with the per-formance of the partial nitritation phase. Therefore, a control strategy for oxidation of ammo-nium to nitrite has been proposed. Controlled oxygen supply to the partial nitritation reactor is obligatory to obtain a proper pH drop indicating oxidation of ammonia to nitrite at the adequate ratio. A very high nitrogen removal efficiency (an average of 84%) and stable operation of the system have been reached. Conductivity measurements were also used to monitor the system influent nitrogen load and the nitrogen removal in the Anammox reactor. The data gathered from the operation of the pilot plant enabled the use of multivariate data analysis to model the process behaviour and the assessment of the covariances between the process parameters. The options for full-scale implementation of the Anammox systems have been proposed as a result of the study.
|
|
| 5. |
- Koseoglu-Imer, Derya Y., et al.
(författare)
-
Current challenges and future perspectives for the full circular economy of water in European countries
- 2023
-
Ingår i: Journal of Environmental Management. - : Elsevier BV. - 0301-4797 .- 1095-8630. ; 345
-
Forskningsöversikt (refereegranskat)abstract
- This paper reviews the current problems and prospects to overcome circular water economy management challenges in European countries. The geopolitical paradigm of water, the water economy, water innovation, water management and regulation in Europe, environmental and safety concerns at water reuse, and technological solutions for water recovery are all covered in this review, which has been prepared in the frame of the COST ACTION (CA, 20133) FULLRECO4US, Working Group (WG) 4. With a Circular Economy approach to water recycling and recovery based on this COST Action, this review paper aims to develop novel, futuristic solutions to overcome the difficulties that the European Union (EU) is currently facing. The detailed review of the current environmental barriers and upcoming difficulties for water reuse in Europe with a Circular Economy vision is another distinctive aspect of this study. It is observed that the biggest challenge in using and recycling water from wastewater treatment plants is dealing with technical, social, political, and economic issues. For instance, geographical differences significantly affect technological problems, and it is effective in terms of social acceptance of the reuse of treated water. Local governmental organizations should support and encourage initiatives to expand water reuse, particularly for agricultural and industrial uses across all of Europe. It should not also be disregarded that the latest hydro politics approach to water management will actively contribute to addressing the issues associated with water scarcity.
|
|
