Département Technologie des procédés

Technologie des procédés

Nos groupes de recherche se consacrent, sous l'angle de l'ingénierie technique, aux problèmes de l'épuration des eaux usées et du traitement de l'eau destinée à la consommation, ainsi qu'à la protection des ressources en eau. Notre objectif est de développer des concepts durables pour les cycles hydrologiques et des nutriments dans les communautés urbaines.

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News

Boîte à outils pour la planification de systèmes sanitaires décentralisés

La boîte à outils contient trois groupes de fiches d'information qui aident à planifier des solutions d'assainissement décentralisé - de la définition des objectifs au choix de la stratégie, en passant par un aperçu des technologies possibles. (Photo : Eawag, Peter Penicka)
18 novembre 2025 –

Une boîte à outils de l'Eawag donne un aperçu des technologies pour les systèmes sanitaires décentralisés, de leurs avantages respectifs et des exemples construits.

Une boîte à outils de l'Eawag donne un aperçu des technologies pour les systèmes sanitaires décentralisés, de leurs avantages respectifs et des exemples construits.
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Les 10 ans du sensor lab de l'Eawag

Une série de capteurs de température avec transmission radio est prête à être entièrement révisée, car les conditions d'utilisation en montagne ou dans les égouts peuvent être difficiles. (Andri Bryner, Eawag)
11 novembre 2025 –

Le Sensorlab fait la fête. Grâce à lui, la recherche sur l'eau reste à la pointe de la technologie, avec de nouvelles solutions de mesure et d'automatisation, de transmission et de gestion des données.

Le Sensorlab fait la fête. Grâce à lui, la recherche sur l'eau reste à la pointe de la technologie, avec de nouvelles solutions de mesure et d'automatisation, de transmission et de gestion des données.
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Système de détection précoce pour les stations d’épuration

Les eaux usées épurées peuvent être surveillées en continu grâce à un monitoring en ligne avec des organismes. Les données ainsi obtenues permettent de réagir rapidement à des pollutions aiguës. (Photo : Centre Ecotox)
17 juin 2025 –

Un système de détection précoce combinant biosurveillance en ligne et analyses chimiques en continu a été testé dans une station d’épuration communale par des chercheuses et chercheurs du Centre Ecotox, de l'Eawag et de la Haute...

Un système de détection précoce combinant biosurveillance en ligne et analyses chimiques en continu a été testé dans une station d’épuration communale par des chercheuses et chercheurs du Centre Ecotox, de l'Eawag et de la Haute école spécialisée du nord-ouest de la Suisse. Le système est capable de détecter les pics de pollution dus à la présence de micropolluants dans les eaux traitées et d’identifier les substances toxiques en temps réel. Il peut ainsi aider à améliorer la gestion des eaux usées.
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Water Hub: Noveau film (en Anglais)

Publications

Appiah-Twum, H., Van Winckel, T., Santolin, J., De Paepe, J., Hellweg, S., Larsen, T. A., … Spiller, M. (2025). Environmental impact of integrating decentralized urine treatment in the urban wastewater management system: a comparative life cycle assessment. Water Research, 282, 123630 (14 pp.). doi:10.1016/j.watres.2025.123630, Institutional Repository

As municipal wastewater treatment regulations become more stringent, integrating source-separated urine treatment into centralized urban wastewater management offers a ‘hybrid’ solution. However, it is not clear how the environmental impacts of such hybrid systems compare to highly efficient centralized wastewater treatment plants (WWTPs) with low N2O emissions and electricity use. In this study, a consequential life cycle assessment was used to compare the environmental impact of three urine separation hybrid wastewater treatment systems – which combine decentralized urine treatment with a highly efficient central WWTP– to a centralized WWTP treating mixed wastewater (baseline). The studied urine treatment systems include partial nitrification & distillation, struvite precipitation & stripping/scrubbing, and partial nitritation/anammox. Additionally, the environmental impact of urine pre-treatment by calcium hydroxide and electrochemical alkalinization methods on the partial nitrification & distillation system was evaluated. The results show that all hybrid scenarios have a lower environmental impact in the freshwater ecotoxicity, marine toxicity, freshwater eutrophication, and marine eutrophication categories compared to the baseline. However, all hybrid scenarios resulted in higher impacts on global warming compared to the baseline, with direct N2O emissions being a key variable. Additionally, it was identified that urine alkalinization increased the environmental impact of the treatment system in 7 out of the 10 impact categories. A Pareto frontier analysis was developed to guide decision makers on where hybrid solutions could be used as a strategy to reduce the global warming impacts of conventional WWTPs. Using N2O-N emission factors of 75 WWTPs, 87 % of centralized WWTPs had a lower global warming impact compared to partial nitrification & distillation, and 91 % compared to partial nitritation/anammox hybrid solutions. However, at electricity demands of 1 kWh/PE/day and 1.5 kWh/PE/day at the central WWTP, both hybrid solutions showed lower global warming impact than all the studied WWTPs. The study highlights the potential of hybrid wastewater treatment solutions as a strategy to reduce global warming impacts in WWTPs with high N2O emissions and electricity use as well as a means to reduce marine eutrophication (i.e. nitrogen pollution).
Bernet, N. M., Soldini, C., Felder, T. M. O., Lapčíková, K., Neubauer, C., Queen, W. L., … Hofstetter, T. B. (2025). Oxygen isotope analyses of phosphate and organophosphorus compounds by electrospray ionization orbitrap mass spectrometry. Analytical Chemistry, 97(41), 22777-22786. doi:10.1021/acs.analchem.5c04367, Institutional Repository

Orbitrap mass spectrometry with electrospray ionization (ESI-Orbitrap MS) enables18O/16O ratio measurements in phosphate and organophosphorus compounds, which offers promising avenues for the study of metabolic, biogeochemical, and environmental processes. While the instrumental feasibility of such18O/16O ratio measurements has been shown, the applicability of such analyses in aqueous matrices on multipurpose mass spectrometers remains unaddressed. Here, we (i) evaluated the interplay between instrument parameters and the long-term accuracy and precision of ESI-Orbitrap MS for the determination of δ18O(PO4) from H2PO4–vs PO3–fragments of phosphate, (ii) identified properties of methanolic sample solutions that are critical for accurate and precise measurements, and (iii) propose a sample purification procedure for the elimination of matrix-based interferences. In 10 measurement campaigns over two years, we observed a long-term reproducibility of δ18O(PO4) within ±2.8‰. Results of in-source fragmentation experiments of H2PO4–to PO3–show excellent agreement of δ18O and offer promising opportunities to probe for18O/16O ratios in organophosphorus compounds. By investigating the effect of the aqueous matrix and interfering anions on18O/16O ratio measurements, we found that a water content exceeding 50 vol % and the presence of oxyanions such as nitrate and sulfate limit measurement accuracy due to interferences of matrix constituents in the ESI source. To overcome these challenges, we evaluated selective phosphate extraction with a zirconium-based metal–organic framework (MOF) as sorbent. The resulting purification procedure allowed for successful extraction and recovery of phosphate from nitrate- and sulfate-containing aqueous solutions, resulting in methanolic phosphate samples that enabled accurate analyses of δ18O(PO4) by ESI-Orbitrap MS.
Braun, D., von Känel, L., Biolley, L., Layer, M., Bieri, R., & Morgenroth, E. (2025). Dynamische Regelung beim Hybridwirbelbettverfahren. ARA Langmatt: Positives Fazit nach zwei Jahren. Aqua & Gas, 105(4), 62-67. , Institutional Repository

Die ARA Langmatt wurde wegen der hohen Belastung mit einer dynamischen Regelung erweitert. Trotz weiterer Erhöhung der Stickstofffrachten während der Optimierungsphase, haben sich die Ablaufwerte von Ammonium und Nirit stark verbessert. Bemerkenswert sind zudem die tiefen Lachgasemissionen und der reduzierte Energieverbrauch mit der neuen Regelung.
Britschgi, L., Wei, S., Proesl, A., Morgenroth, E., & Derlon, N. (2025). The critical role of flocs in nitrification in full-scale aerobic granular sludge-based WWTP. Water Research, 274, 123021 (13 pp.). doi:10.1016/j.watres.2024.123021, Institutional Repository

Aerobic granular sludge (AGS) is usually considered to be a biofilm system consisting of granules only, although practical experience suggests that flocs and granules of various sizes co-exist. This study thus focused on understanding the contribution of flocs and granules of various sizes to nitrification in a full-scale AGS-based wastewater treatment plant (WWTP) operated as a sequencing batch reactor (SBR). The size distribution in terms of total suspended solids (TSS) and the distribution of the nitrifying communities and activities were monitored over 14 months. Our results indicate that AGS is a hybrid system in which flocs (<0.25 mm) play a critical role in nitrification. AGS consisted of 36 % flocs and 50 % large granules (>2 mm) at a TSS concentration of 4.7 ± 0.7 gTSS L-1. The growth of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in large granules was limited due to the high mass transfer limitation in biofilm and the high solids retention time (SRT) of flocs, where favorable conditions for the growth of nitrifiers were maintained during the warm season. The specific activities of the small aggregates (<1 mm) were 5 to 15 times higher than those of large granules. As a result, flocs contributed >50 % to nitrification during the warm season, whereas granules >1 mm contributed <20 %. Such predominance of flocs in nitrification became problematic in the cold season when the minimum SRT of NOB increased to values similar to the floc SRT, resulting in 79 % loss of the NOB. Consequently, NOB activities dropped, and elevated effluent nitrite concentrations of several mgN L-1 were monitored. We suggest operating AGS systems similarly to hybrid systems in order to promote the enrichment of NOB in the granules by controlling the floc SRT at low values smaller than the minimum SRT of NOB throughout the year.

Événements

04.12.​2025,
9h00
Eawag Dübendorf
Emissions et impact des particules de pneus dans l’environnement

Cours de base PEAK-B36/25

20.01.​2026,
9h00
Eawag Dübendorf
Systèmes d'assainissement circulaires : technologies, opportunités et défis

Cours de base PEAK-VaLoo B37/26

Projets de recherche

Is a space research program, aiming to develop a bioregenerative life support system for long-term space missions and space habitations for example on Mars.

Melissa «Micro Ecological Life Support System Alternative»
NEST building
La gestion durable d'eaux potable et usées appliquée et mise en pratique dans le bâtiment modulaire NEST.

WaterHub au NEST
Modelling of aerobic granular sludge (AGS) reactors

Eawag Aerobic Granular Sludge (AGS) Model
Many WWTPs are reaching their maximum treatment and clarification capacities, and solutions must be found to upgrade those existing plants.

Micro-sieving of municipal wastewater
Opportunities and risks of reusing treated wastewater in Switzerland

Water Reuse Switzerland
The Swiss Federal Council set the ambitious goal to reach net-zero greenhouse gas emissions by 2050.

SCENE - Reducing N2O emissions from wastewater treatment
Dynamic of greenhouse gas emissions in nutrient removing wastewater treatment plants

N2O - Dynamic of greenhouse gas emissions
Systematic investigation of hybrid model approaches for the prediction of nitrous oxide emissions in biological wastewater treatment

MAD4WW

Autres projets de recherche