1
|
Statiris E, Dimopoulos T, Petalas N, Noutsopoulos C, Mamais D, Malamis S. Investigating the long and short-term effect of free ammonia and free nitrous acid levels on nitritation biomass of a sequencing batch reactor treating thermally pre-treated sludge reject water. Bioresour Technol 2022; 362:127760. [PMID: 35963489 DOI: 10.1016/j.biortech.2022.127760] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
This work examined the short and long-term effects of different free ammonia (FA) and free nitrous acid (FNA) levels on (i) acclimatized biomass treating sludge reject water via nitrite in a sequencing batch reactor (SBR) and (ii) non-aclimatized biomass treating municipal wastewater via nitrate in the activated sludge process. In the acclimatized biomass, the threshold for the transition from nitrification to nitritation was the FA increase to 10-20 mgNH3-N/L while the SBR unit showed no inhibition on the ammonia uptake rate (AUR) at FA levels up to 65 mgNH3-N/L. Short-term exposure of the acclimatized biomass on FNA showed that AUR inhibition could be more than 50 % for FNA concentration >10 μgHNO2-N/L. The FNA inhibition results were simulated using non-competitive inhibition kinetics that showed that the inhibition constant corresponding to the FNA concentration that inhibits the process by 50 % (i.e. KiFNA) was much higher in the acclimatized biomass.
Collapse
Affiliation(s)
- E Statiris
- Sanitary Engineering Laboratory, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou St., Zographou Campus, 15780-GR Athens, Greece.
| | - T Dimopoulos
- Sanitary Engineering Laboratory, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou St., Zographou Campus, 15780-GR Athens, Greece
| | - N Petalas
- Sanitary Engineering Laboratory, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou St., Zographou Campus, 15780-GR Athens, Greece
| | - C Noutsopoulos
- Sanitary Engineering Laboratory, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou St., Zographou Campus, 15780-GR Athens, Greece
| | - D Mamais
- Sanitary Engineering Laboratory, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou St., Zographou Campus, 15780-GR Athens, Greece
| | - S Malamis
- Sanitary Engineering Laboratory, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou St., Zographou Campus, 15780-GR Athens, Greece
| |
Collapse
|
2
|
Plevri A, Mamais D, Noutsopoulos C. Anaerobic MBR technology for treating municipal wastewater at ambient temperatures. Chemosphere 2021; 275:129961. [PMID: 33677279 DOI: 10.1016/j.chemosphere.2021.129961] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/31/2021] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
An innovative way to treat municipal wastewater and produce energy at the same time is anaerobic treatment. Anaerobic processes are traditionally used for high-strength wastewater or municipal sludge treatment and only recently have been applied for the treatment of low strength municipal wastewater To investigate the performance of anaerobic wastewater treatment through the incorporation of membrane technology, a 40 L laboratory scale Anaerobic Membrane Bioreactor (AnMBR) with a flat sheet submerged membrane along with a 40 L reservoir for trapping and measuring the biogas produced have been installed and set in operation. The scope of this study is to examine, through long term bench scale experiments, the impact that different temperatures and also different operating conditions have on the efficiency of AnMBR in order to identify the possibility of integrating this technology into Wastewater Treatment Plants (WWTPs). This paper evaluates the efficiency of AnMBR in the temperature range 14-26 °C, operating at three different hydraulic retention times (HRTs). The three different HRTs examined were 2 d, 1 d and 12 h. Each HRT is divided into two different temperature ranges. As the HRT decreased the effluent quality decreased and the membrane fouled more rapidly. AnMBR was able to produce permeate water with an average COD of 51 ± 8 mg L-1 at an HRT of 2 d during the summer period with an average temperature of 24 °C. The effluent COD increased to 67 ± 10 mg L-1 and reached 91 ± 5 mg L-1 for HRT 1 d and 12 h respectively for the same temperature range.
Collapse
Affiliation(s)
- A Plevri
- Sanitary Engineering Laboratory, Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Polytechniou 9, Zografou, 157 80, Athens, Greece.
| | - D Mamais
- Sanitary Engineering Laboratory, Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Polytechniou 9, Zografou, 157 80, Athens, Greece
| | - C Noutsopoulos
- Sanitary Engineering Laboratory, Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Polytechniou 9, Zografou, 157 80, Athens, Greece
| |
Collapse
|
3
|
Panousi E, Mamais D, Noutsopoulos C, Mpertoli K, Kantzavelou C, Nyktari E, Kavallari I, Nasioka M, Kaldis A. Biological groundwater treatment for hexavalent chromium removal at low chromium concentrations under anoxic conditions. Environ Technol 2019; 40:365-373. [PMID: 29032730 DOI: 10.1080/09593330.2017.1393013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 10/02/2017] [Indexed: 06/07/2023]
Abstract
The objective of this work is to evaluate biological groundwater treatment systems that will achieve hexavalent chromium removal from groundwater at hexavalent chromium (Cr(VI)) groundwater concentrations in the 0-200 μg/L range under anoxic conditions. The effect of type of organic substrate added as feed to the groundwater treatment system (milk, sugar and cheese whey), the effect of different concentrations of chemical oxygen demand added in the feed (100, 150 and 200 mg/L) and the effect of different hydraulic residence time (1.7, 0.9 and 0.7 d) on process performance were evaluated through the operation of a series of sequential batch reactors under anoxic conditions. Biomass receiving Cr(VI) contaminated groundwater with a low nitrates content exhibited similar Cr(VI) removal efficiency under reductive conditions, with biomass receiving Cr(VI) contaminated groundwater with a high nitrates content. The concentration of organic substrate was crucial for the microbial reduction of Cr(VI). The different hydraulic residence time of the reactors and the different types of organic substrates added did not affect the efficiency of hexavalent chromium removal which was complete. This study demonstrates that biological systems operating under reductive conditions can efficiently treat groundwater containing low or high nitrates concentration and can provide complete hexavalent chromium removal at initial Cr(VI) concentrations of 200 μg/L.
Collapse
Affiliation(s)
- E Panousi
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - D Mamais
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - C Noutsopoulos
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - K Mpertoli
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - C Kantzavelou
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - E Nyktari
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - I Kavallari
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - M Nasioka
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| | - A Kaldis
- a Department of Water Resources and Environmental Engineering , School of Civil Engineering, National Technical University of Athens , Athens , Greece
| |
Collapse
|
4
|
Makropoulos C, Rozos E, Tsoukalas I, Plevri A, Karakatsanis G, Karagiannidis L, Makri E, Lioumis C, Noutsopoulos C, Mamais D, Rippis C, Lytras E. Sewer-mining: A water reuse option supporting circular economy, public service provision and entrepreneurship. J Environ Manage 2018; 216:285-298. [PMID: 28728973 DOI: 10.1016/j.jenvman.2017.07.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 06/28/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
Water scarcity, either due to increased urbanisation or climatic variability, has motivated societies to reduce pressure on water resources mainly by reducing water demand. However, this practice alone is not sufficient to guarantee the quality of life that high quality water services underpin, especially within a context of increased urbanisation. As such, the idea of water reuse has been gaining momentum for some time and has recently found a more general context within the idea of the Circular Economy. This paper is set within the context of an ongoing discussion between centralized and decentralized water reuse techniques and the investigation of trade-offs between efficiency and economic viability of reuse at different scales. Specifically, we argue for an intermediate scale of a water reuse option termed 'sewer-mining', which could be considered a reuse scheme at the neighbourhood scale. We suggest that sewer mining (a) provides a feasible alternative reuse option when the geography of the wastewater treatment plant is problematic, (b) relies on mature treatment technologies and (c) presents an opportunity for Small Medium Enterprises (SME) to be involved in the water market, securing environmental, social and economic benefits. To support this argument, we report on a pilot sewer-mining application in Athens, Greece. The pilot, integrates two subsystems: a packaged treatment unit and an information and communications technology (ICT) infrastructure. The paper reports on the pilot's overall performance and critically evaluates the potential of the sewer-mining idea to become a significant piece of the circular economy puzzle for water.
Collapse
Affiliation(s)
- C Makropoulos
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Politechniou 5, 157 80, Zografou, Athens, Greece.
| | - E Rozos
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Politechniou 5, 157 80, Zografou, Athens, Greece
| | - I Tsoukalas
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Politechniou 5, 157 80, Zografou, Athens, Greece
| | - A Plevri
- Athens Water and Sewerage Company S.A (EYDAP) - Research and Development - Oropou 156, 11146, Galatsi, Athens, Greece
| | - G Karakatsanis
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Politechniou 5, 157 80, Zografou, Athens, Greece
| | - L Karagiannidis
- Institute of Communication and Computer Systems, National Technical University of Athens, 9 Iroon Polytechniou Str., 157 80, Zografou, Athens, Greece
| | - E Makri
- TELINT RTD Consultancy Services Ltd., 1 Westferry Circus Canary Wharf, London, United Kingdom
| | - C Lioumis
- CHEMITEC Technical and Commercial Company, 23, Spyrou Vrettou Str., 136 71, Acharnes, Athens, Greece
| | - C Noutsopoulos
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Politechniou 5, 157 80, Zografou, Athens, Greece
| | - D Mamais
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, Iroon Politechniou 5, 157 80, Zografou, Athens, Greece
| | - C Rippis
- Athens Water and Sewerage Company S.A (EYDAP) - Research and Development - Oropou 156, 11146, Galatsi, Athens, Greece
| | - E Lytras
- Athens Water and Sewerage Company S.A (EYDAP) - Research and Development - Oropou 156, 11146, Galatsi, Athens, Greece
| |
Collapse
|
5
|
Panagiotakis I, Antoniou K, Mamais D, Pantazidou M. Effects of different electron donor feeding patterns on TCE reductive dechlorination performance. Bull Environ Contam Toxicol 2015; 94:289-294. [PMID: 25613854 DOI: 10.1007/s00128-015-1462-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 01/12/2015] [Indexed: 06/04/2023]
Abstract
This study investigates how the feeding pattern of e(-) donors might affect the efficiency of enhanced in situ bioremediation in TCE-contaminated aquifers. A series of lab-scale batch experiments were conducted using butyrate or hydrogen gas (H2) as e(-) donor and a TCE-dechlorinating microbial consortium dominated by Dehalococcoides spp. The results of these experiments demonstrate that butyrate is similarly efficient for TCE dechlorination whether it is injected once or in doses. Moreover, the present work indicates that the addition of butyrate in great excess cannot be avoided, since it most likely provide, even indirectly, significant part of the H2 required. Furthermore, methanogenesis appears to be the major ultimate e(-) accepting process in all experiments, regardless the e(-) donor used and the feeding pattern. Finally, the timing of injection of H2 seems to significantly affect dechlorination performance, since the injection during the early stages improves VC-to-ETH dechlorination and reduce methanogenic activity.
Collapse
Affiliation(s)
- I Panagiotakis
- School of Civil Engineering, National Technical University of Athens, 157 80, Zografou, Greece,
| | | | | | | |
Collapse
|
6
|
Kandris K, Antoniou K, Pantazidou M, Mamais D. Modelling microbial dechlorination of trichloroethene: investigating the trade-off between quality of fit and parameter reliability. Bull Environ Contam Toxicol 2015; 94:295-301. [PMID: 25447439 DOI: 10.1007/s00128-014-1436-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 11/27/2014] [Indexed: 06/04/2023]
Abstract
This work puts forth a heuristic approach for investigating compromises between quality of fit and parameter reliability for the Monod-type kinetics employed to model microbial reductive dechlorination of trichloroethene. The methodology is demonstrated with three models of increasing fidelity and complexity. Model parameters were estimated with a stochastic global optimization algorithm, using scarce and inherently noisy experimental data from a mixed anaerobic microbial culture, which dechlorinated trichloroethene to ethene completely. Parameter reliability of each model was assessed using a Monte Carlo technique. Finally, an alternate quantity of applied interest was evaluated in order to assist with model discrimination. Results from the application of our approach suggest that the modeler should examine the implementation of conceptually simple models, even if they are a crude abstraction of reality, as they can be computationally less demanding and adequately accurate when model performance is assessed with criteria of applied interest, such as chloroethene elimination time.
Collapse
Affiliation(s)
- K Kandris
- School of Civil Engineering, National Technical University of Athens, Iroon Polytechniou 9, Zografou, 157 80, Athens, Greece,
| | | | | | | |
Collapse
|
7
|
Mamais D, Noutsopoulos C, Dimopoulou A, Stasinakis A, Lekkas TD. Wastewater treatment process impact on energy savings and greenhouse gas emissions. Water Sci Technol 2015; 71:303-308. [PMID: 25633956 DOI: 10.2166/wst.2014.521] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The objective of this research was to assess the energy consumption of wastewater treatment plants (WWTPs), to apply a mathematical model to evaluate their carbon footprint, and to propose energy saving strategies that can be implemented to reduce both energy consumption and greenhouse gas (GHG) emissions in Greece. The survey was focused on 10 WWTPs in Greece with a treatment capacity ranging from 10,000 to 4,000,000 population equivalents (PE). Based on the results, annual specific energy consumption ranged from 15 to 86 kWh/PE. The highest energy consumer in all the WWTPs was aeration, accounting for 40-75% of total energy requirements. The annual GHG emissions varied significantly according to the treatment schemes employed and ranged between 61 and 161 kgCO₂e/PE. The highest values of CO₂emissions were obtained in extended aeration systems and the lowest in conventional activated sludge systems. Key strategies that the wastewater industry could adopt to mitigate GHG emissions are identified and discussed. A case study is presented to demonstrate potential strategies for energy savings and GHG emission reduction. Given the results, it is postulated that the reduction of dissolved oxygen (DO) set points and sludge retention time can provide significant energy savings and decrease GHG emissions.
Collapse
Affiliation(s)
- D Mamais
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou, Zografou, Athens 15780, Greece E-mail:
| | - C Noutsopoulos
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou, Zografou, Athens 15780, Greece E-mail:
| | - A Dimopoulou
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou, Zografou, Athens 15780, Greece E-mail:
| | - A Stasinakis
- Department of Environment, University of the Aegean, University Hill, Mytilene 81100, Greece
| | - T D Lekkas
- EYDAP, 156 Oropou St., Athens 11146, Greece
| |
Collapse
|
8
|
Noutsopoulos C, Mamais D, Antoniou K, Avramides C, Oikonomopoulos P, Fountoulakis I. Anaerobic co-digestion of grease sludge and sewage sludge: the effect of organic loading and grease sludge content. Bioresour Technol 2013; 131:452-459. [PMID: 23380711 DOI: 10.1016/j.biortech.2012.12.193] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 12/23/2012] [Accepted: 12/26/2012] [Indexed: 06/01/2023]
Abstract
The objective of this study was to assess the feasibility of co-digesting grease sludge (GS) originating from domestic wastewater along with sewage sludge (SS) and to assess the effect of organic loading rate (OLR) and GS content on process performance. Three lab-scale semi-continuous fed mesophilic anaerobic digesters were operated under various OLRs and SS-GS mixtures. According to the results, addition of GS up to 60% of the total VS load of feed resulted in a 55% increase of biogas yield (700 vs. 452m(3)/tVSadded) for an OLR of 3.5kg VS/m(3)/d. A stable and satisfactory operation of anaerobic co-digestion units can be achieved for a GS-OLR up to 2.4kg VSGS/m(3)/d. For such values biogas yield is linearly proportional to the applied GS-OLR, whereas biogas yield is minimal for GS-OLR higher than this limit and acidification of the anaerobic digestion units is taking place.
Collapse
Affiliation(s)
- C Noutsopoulos
- National Technical University of Athens, School of Civil Engineering, Department of Water Resources and Environmental Engineering, 5 Iroon Polytechniou, Zografou, Athens 15780, Greece.
| | | | | | | | | | | |
Collapse
|
9
|
Noutsopoulos C, Mamais D, Samaras V, Bouras T, Marneri M, Antoniou K. Effect of wastewater chlorination on endocrine disruptor removal. Water Sci Technol 2013; 67:1551-1556. [PMID: 23552244 DOI: 10.2166/wst.2013.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Endocrine disrupting chemicals (EDCs) are compounds of mainly anthropogenic origin that interfere with the endocrine system of animals and humans thus causing a series of disorders. Wastewater treatment plants are one of the major routes for transporting such chemicals to the water courses. In the context of this study, several chlorination batch tests were performed in order to assess the effectiveness of chlorination to remove bisphenol A (BPA), triclosan (TCS), nonylphenol (NP) and its ethoxylates (NP1EO and NP2EO) from secondary effluent. According to the results, an appreciable removal of NP, BPA and TCS to the order of 60-84% was observed as an effect of moderate chlorination doses. This was not the case for NP1EO and NP2EO as even at high chlorine doses, removal efficiencies were lower (37% for NP1EO and 52% for NP2EO). Removal efficiencies of NP, BPA and TCS are practically independent of contact time, although this was not the case for NP1EO and NP2EO. Based on toxicity experiments, it is anticipated that following chlorination of the target chemicals, production of more toxic metabolites is taking place. Therefore the effectiveness of chlorination to remove EDCs is questionable and more research is needed to guarantee safe wastewater reuse.
Collapse
Affiliation(s)
- C Noutsopoulos
- Department of Water Resources and Environmental Engineering, School of Civil Engineering, National Technical University of Athens, 5 Iroon Polytechniou, Zografou 15780, Athens, Greece.
| | | | | | | | | | | |
Collapse
|
10
|
Mamais D, Noutsopoulos C, Andreadakis A, Droubogianni J, Georgakopoulos A, Tsepapadakis E, Mariolos J. Optimization of nitrogen removal and start-up of Psyttalia sewage treatment works. Environ Technol 2007; 28:129-36. [PMID: 17396406 DOI: 10.1080/09593332808618779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Bench scale experiments were conducted in order to finalize the design of the secondary treatment stage of Psyttalia Sewage Treatment Works that serves the Greater Athens area with a population equivalent of 3.5 million. Carbon and nitrogen removal efficiencies and activated sludge settling characteristics were determined through continuous flow experiments and determination of the maximum specific utilization rates of ammonia (AUR) and nitrate (NUR). According to the results of the pilot experiments the need arose for a significant increase in the initial design's anoxic volume to ensure a 70% average annual nitrogen removal. AUR experiments showed an insignificant inhibition to the nitrification process in the order of 0-30%, representative of typical domestic sewage. The findings of the pilot study were in good agreement with full scale data obtained during the start up of Psyttalia biological treatment plant. According to full scale data and AUR tests a very satisfactory nitrogen removal efficiency was obtained during start up. Finally both lab scale and full scale data indicated that the activated sludge plant operating on Psyttalia primary effluent that has a high oil and grease content, is prompt to experience foaming problems due to the excessive growth of filamentous microorganisms M. parvicella and Gordona amarae - like microorganisms.
Collapse
Affiliation(s)
- D Mamais
- National Technical University of Athens, Faculty of Civil Engineering, Department of Water Resources, Hydraulic and Maritime Engineering, 5, Iroon Polytechniou, Zografou, Athens 15780, Greece
| | | | | | | | | | | | | |
Collapse
|
11
|
Noutsopoulos C, Andreadakis A, Mamais D, Gavalakis E. Identification of type and causes of filamentous bulking under Mediterranean conditions. Environ Technol 2007; 28:115-22. [PMID: 17283955 DOI: 10.1080/09593332808618771] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
A national survey to identify the most common filamentous microorganisms in Greek wastewater treatment plants, to assess the extent of filamentous bulking phenomenon and to correlate the occurrence of these bacteria to specific operating parameters, was carried out for five years. According to the conclusions of this survey filamentous bulking is a widespread phenomenon in Greek wastewater treatment plants. Almost 70% of the sludge samples examined exhibited filament indices greater than 4 during the winter period. The most common filamentous species found in a decreasing order were M. parvicella, Type 0092, GALOs, Type 0041 and N. limicola. A seasonal variation of the composition of the biomass was observed. M. parvicella is the dominant species during winter periods, while T0092 is the dominant species during summer conditions. This seasonal pattern of biomass composition was followed by a similar seasonal variation of the settling characteristics in terms of Filament Index (FI) and Sludge Volume Index (SVI) values. M. parvicella's proliferation is favored in Carrousel and oxidation ditches systems especially when primary settling stage was preceeded, whereas its growth is also highly stimulated in intermittent aeration systems, even in the absence of primary settling tanks. Finally there is evidence that Bio-P systems without primary sedimentation inhibit its growth.
Collapse
Affiliation(s)
- C Noutsopoulos
- National Technical University of Athens, Faculty of Civil Engineering Department of Water Resources, Hydraulic and Maritime Engineering 5, Iroon Polytechniou, Zografou, Athens 15780, Greece
| | | | | | | |
Collapse
|
12
|
Noutsopoulos C, Mamais D, Andreadakis AD. The effect of reactor configuration and operational mode on Microthrix parvicella bulking and foaming in nutrient removal activated sludge systems. Water Sci Technol 2002; 46:61-64. [PMID: 12216689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Three bench-scale nutrient removal activated sludge units were used to examine the effect of the reactor configuration and the intermittent aeration mode on the growth of Microthrix parvicella. According to the results, the plug flow configuration seems to achieve satisfactory Microthrix parvicella control. The imposed concentration gradient for both RBCOD and SBCOD creates a selective advantage for the floc forming bacteria throughout the system (both the anoxic and oxic zones) and limits Microthrix parvicella growth. In terms of the operational mode, the intermittent aeration CSTR nutrient removal system promotes the growth of M. parvicella and deteriorates the settling characteristics of the activated sludge.
Collapse
Affiliation(s)
- C Noutsopoulos
- Department of Water Resources, Faculty of Civil Engineering, National Technical University of Athens, Greece
| | | | | |
Collapse
|