Thirty-one laboratories measured biochemical methane potential (BMP) of six substrates in a project aimed at improving BMP measurement quality. Laboratories used their established measurement procedures, with limited standardization. As in earlier studies, reproducibility was quantified, but here laboratories came from a wide geographic range, and the accuracy of BMP measurements was assessed by comparison with 6 experienced “reference” laboratories. Measurement reproducibility between the remaining “evaluation” laboratories was poor in the first test; relative reproducibility standard deviation was 21–33% for four substrates. Values improved to 9–19% in the second test following review of a detailed analysis of submitted data, troubleshooting meetings, and method modifications by some laboratories. Reference laboratories performed better, with reproducibility standard deviation of 5–12%. Repeatability within laboratories was also better for the reference group, with relative standard deviation of 2–4% vs. 3–7% for evaluation laboratories. Evaluation laboratory results showed a persistent negative bias of 4–16% compared to reference laboratories. Application of cellulose validation criteria improved reproducibility but not accuracy. Most of the extreme BMP values were associated with abnormal methane production curves, and a subjective visual evaluation proved valuable as a screening tool. The cause of measurement error was generally unknown, although data processing and volatile solids measurement errors caused some extreme results, and changes in inoculum source improved performance in two cases. There were no consistent differences among the diverse measurement methods and the sources of error probably vary among laboratories. Consistently accurate BMP measurement is possible for laboratories that follow established guidelines and develop experience.
Darin plädiert der Beirat für eine vieldimensionale Sicherheitsarchitektur. Sie soll nicht nur die Bekämpfung von Umweltrisiken enger mit sicherheitspolitischen Instrumenten verzahnen, sondern auch weitere Themen einbinden.
Insgesamt fünf Handlungsfelder hat der WBGU identifiziert, die aus seiner Sicht im nationalen wie internationalen Sicherheitskontext entscheidend sind.
🔹 1. Schutz vor Klimawandel, Biodiversitätsverlust und Verschmutzung, um die Lebensfähigkeit der Menschheit zu bewahren.
🔹 2. Sozialer Zusammenhalt, um resiliente Gesellschaften zu fördern.
🔹 3. Informationsintegrität, um die Demokratie wehrhaft zu machen.
🔹 4. Abgewogene Nutzung von Technologien und Rohstoffen, um Abhängigkeiten zu reduzieren.
🔹 5. Strategische, regelbasierte und faire Kooperation, um die internationale Zusammenarbeit zu stützen.
Als zusätzlichen Impuls für die sicherheitspolitische Debatte hat der WBGU für alle fünf Schwerpunkte konkrete Handlungsempfehlungen erarbeitet, etwa zum Thema ‚Sicherheit durch Klimaschutz‘, zur Ausgestaltung von technologischer Souveränität, zum Umgang mit KI-generierten Falschinformationen und gesellschaftsspaltender Kommunikation sowie zur Neuordnung der internationalen Zusammenarbeit.
Die Leitautor:innen des Kurzpapiers sind: Jörg E. Drewes, Anna-Katharina Hornidge, Aletta Bonn, Kai Maaz, Karen Pittel, Hans Pörtner, Sabine Dr. Schlacke, Claudia Traidl-Hoffmann, Joscha Wullweber.
Sicherheit – nachhaltig und integriert
Quelle: Bundesministerium für Umwelt, Klimaschutz, Naturschutz und nukleare Sicherheit (BMUKN)
Das Verbundvorhaben „Wasserresilienz“ teilt erste Erkenntnisse auf der 59. Essener Tagung mit einem Vortrag und einem Posterbeitrag: ‚Anforderungen und Aufbau einer KI-gestützten Optimierung der Grundwasserbewirtschaftung und des Lastenmanagements der Hessenwasser GmbH & Co KG‘
Applying the counter-current principle, i.e. recirculating half-loaded PAC into the activated sludge process, will boost your process performance!
Curious?
Check out our open-access publication:
https://www.nature.com/articles/s41545-026-00561-y
Big thanks to Max Zimmermann, all involved project partners and BMFTR for funding this study.
Calcium precipitation in granular sludge frequently threatens the stability and efficiency of biological nitrogen removal, yet most studies focus on slow, progressive calcification during long-term operation. Here, we report for the first time a transient calcification phenomenon in PD-HAP coupled granular sludge, where nitrite accumulation activity collapses within 24 h under fluctuating influent conditions (NO3−-N deficiency). Microstructural analyses revealed that amorphous calcium phosphate (ACP) initially deposits on the granule surface and migrates inward through axial mineral channels driven by microbial metabolism. Through the Ostwald ripening process, ACP gradually transforms into hydroxyapatite (HAP), simultaneously forming the characteristic Liesegang ring patterns. When microbial activity declines and migration driving forces are insufficient, surface deposition outpaces inward transformation, generating a transient calcium crust that blocks substrate-bacteria contact and triggers rapid activity loss. Over time, the repeated occurrence of such surface deposits and mineral phase transformations can ultimately form a more compact and stable mineral coating, exhibiting characteristics of progressive long-term calcium accumulation. Notably, this granular system achieves self-regulation by fracturing into functional micro components (d < 0.2 mm), thereby restoring the system's exceptional nitrite accumulation capacity. These results elucidate the mechanistic basis of transient calcification, highlight the critical role of microbial metabolism in controlling calcium migration, and provide actionable strategies for mitigating calcification shocks in industrial wastewater treatment. Understanding these processes offers a foundation for designing granular sludge systems with enhanced resilience against sudden influent fluctuations and high-calcium wastewater.
Building products, like non-metal roofing materials, can contribute pollutants to stormwater. Laboratory leaching tests, particularly the dynamic surface leaching test (DSLT), are employed to evaluate the substance release, but are not designed to simulate field conditions. By comparing results from a DSLT and a 6-month field study for the same materials (clay tiles, concrete tiles, fiber cement sheets, bitumen shingles, treated wood shingles, and plastic tiles) and same analyzed inorganic and organic parameters we provided a basis for interpreting and translating the DSLT outcome to real weather conditions. The objective was to evaluate the reliability of the DSLT in predicting which parameter types are leached from non-metal roofing materials in the field, as well as its suitability for estimating the corresponding concentration levels. The comparison demonstrated that the DSLT reliably predicted more than 80% of pollutants released under environmental conditions, supporting its use for investigating new roofing materials or emerging pollutants to identify parameters contributing to stormwater pollution. Our results serve as a database for interpreting DSLT results and for developing and calibrating transfer models. However, no general pattern was observed between laboratory and field results: for fiber cement, clay and concrete tiles, the DSLT overestimated the concentrations; median concentrations exceeded those in the field, with factors of 2.6 to 115. For bitumen and wood shingles, the DSLT rather underestimated the substance release, resulting in median field concentrations that exceeded those in the laboratory by factors of 1.3 to 10.4. Consequently, transfer models must account for different surface properties of the materials.
Leachate infiltration into groundwater is an intensifying environmental and public health concern in many developing countries, where waste disposal systems are poorly engineered. Phenolic contaminants pose significant ecological and human health risks but remain understudied in sub-Saharan Africa. This study investigated the seasonal occurrence, distribution, and associated risks of four phenolic compounds, namely bisphenol A (BPA), hydroquinone (HQ), resorcinol (RE), and benzoquinone (BQ), in groundwater sources near municipal dumpsites across three Southwestern States in Nigeria. Groundwater samples were collected from rural and urban areas across Osun, Oyo, and Lagos States during both rainy and dry seasons. Solid-phase extraction and high-performance liquid chromatography-ultraviolet detector (HPLC-UV) analysis were used to extract and quantify the target analytes, followed by multivariate statistical evaluation, human health risk assessment, and ecological risk assessment. Concentrations of BPA, HQ, RE, and BQ were generally higher during the dry season, especially in Osun and Lagos States. BPA recorded the highest values, peaking at 20.90 mg L−1 in urban Osun. RE and BQ also showed elevated levels during the dry season, particularly in urban Lagos and rural Oyo, respectively. HQ exhibited variable trends, with significant peaks in rural Oyo (11.93 mg L−1) and rural Osun (7.26 mg L−1). Multivariate analysis via principal component revealed clear seasonal differentiation and strong co-loading patterns consistent with leachate-driven contamination processes. Human health risk assessment indicated that estimated daily intakes in children frequently exceeded stipulated limits, while ecological risk assessment identified Daphnia magna as the most sensitive species, with acute and chronic risk quotients exceeding the reference dose in several locations. This study represents the first year-long, multi-state assessment of phenolic contaminants in Nigerian groundwater and provides critical evidence of contamination levels linked to unmanaged waste sites. These findings highlight the urgent need for improved waste management, groundwater protection policies, and expanded toxicological evaluation of phenolic contaminants in rapidly urbanizing regions of sub-Saharan Africa.
Am 19. März veranstalten wir ein C.A.R.M.E.N.-Fachgespräch zum Thema „Biologische Methanisierung“ bei uns im Haus, inklusive eine Führung zu unserer Pilotanlage auf der Kläranlage Garching. Wir freuen uns auf zahlreiche Teilnehmer.
Weitere Informationen und die Anmeldung gibt es unter https://www.carmen-ev.de/events/c-a-r-m-e-n-fachgespraech-biologische-methanisierung/.
An automated sampling system has been installed on a 1000m² green roof at the O2-Surftown in Hallbergmoos, and a student research assistant is needed to further process the samples.
Working hours: approx. 8 hours per week
Location: TUM Campus Garching (Chair of Urban Water Management, SiWaWi)
Start date: April 2026
Glyphosate Bildung durch Waschmittel in Kläranlagen? Was ist dran? s. Minute 8:00.
This study investigated the performance and nitrous oxide (N₂O) emission dynamics of algal-bacterial granular sludge (ABGS) cultivated in a 40 L sequencing batch photobioreactor (SBPBR) treating real domestic wastewater, without initial external inoculum. ABGS formation was successfully achieved and remained stable over 180 days, with stable granule structure (> 1000 µm), good settling properties (SVI₃₀ of 42 mL· gVSS⁻¹), and chlorophyll-a content of 1.2 ± 0.1 mg· gVSS⁻¹. The system remained resilient to disturbances, including tubifex proliferation, confirming the structural viability of ABGS under non-sterile conditions. Regarding treatment performance, the reactor achieved consistent COD removal (> 80 %) and efficient ammonium removal (> 97 %) after microbial community adaptation. However, phosphorus removal was moderate (52 %), limited by the lack of anaerobic cycling and absence of excess sludge removal. N2O dynamics were monitored under four operational scenarios: low/high dissolved oxygen (DO) (2–3 and 6–7 mg· L⁻¹) and with/without light. N₂O production on liquid phase was mainly influenced by DO concentration, as lower DO levels resulted in higher N₂O emissions, while light had only a minor effect on its dynamics. However, under high DO conditions (10 L· min⁻¹, kLa = 283 h⁻¹), N₂O in the gas phase (emission factor, EF) reached 3.4 %, which was considerably higher than under low DO (3 L· min⁻¹, kLa = 100 h⁻¹), where EF remained below 1 %. This outcome indicates that oxygen availability is the dominant driver of N₂O formation, with light exerting only a secondary influence. These results emphasize the dual control of N₂O by microbial pathways and physical mass transfer, underscoring the need to optimize aeration strategies in ABGS reactors to balance nitrogen removal and greenhouse gas mitigation.
The Water Hub research facility is managed by the University of Cape Town’s Future Water Institute and is located in Franschhoek.
A PhD scholarship is being offered for research that focuses on advancing the use of nature-based treatment to remove organic matter, pathogens, contaminants of emerging concern (CECs) and excessive nutrient loads from decentralised wastewater streams. This project forms part of an ongoing programme with international collaborators demonstrating how low-energy, low-cost natural treatment systems can support safe water reuse and improved water security in resource-constrained contexts.
Location: The Water Hub, Franschhoek, South Africa
Starting Date: 2026
Duration: 3 years, full-time
A PhD scholarship is being offered to research the optimisation and assessment of the operation of a 100kg containerised biodigester system capable of converting food and organic waste into biogas for heating and refrigeration and using digestate for small-scale agroecology production.
Location: The Water Hub, Franschhoek, South Africa
Starting Date: 2026 (flexible)
Duration: 3 years, full-time
Heute ist der Trinkwasser-Grenzwert für die Summe von 20 PFAS in Kraft getreten. Damit sind PFAS erstmals in der EU und in Deutschland reguliert. Wenn Sie wissen wollen, was das für Sie bedeutet und welche Maßnahmen Sie als Versorger nun bei Überschreitungen ergreifen müssen, dann melden Sie sich zu unserem 34. Wassertechnischen Seminar (WTS) am 4. Februar 2026 an. In unserem Webinar informieren wir umfassend zu den Neuerungen rund um PFAS.
As urban road runoff is a critical source of water contamination, it poses a persistent challenge to water quality management, particularly in compact cities. Yet the sources, transport mechanisms, interactions, and ecological risks of these co‑occurring contaminants remain insufficiently understood. Therefore, we investigated 32 stormwater quality parameters in runoff from six representative road sites across 11 rainfall events over a 17-month period in Hong Kong. Contaminant levels in initial road runoff were markedly higher than those in natural rainwater; notably, Escherichia coli concentrations were more than four orders of magnitude greater. Concentrations of organic matter, solids, nutrients, pathogens, and metals in the initial road runoff exceeded the Water Pollution Control Ordinance (WPCO) objectives in Hong Kong by several to dozens of times. A pronounced first flush effect was observed for chemical oxygen demand (COD), total suspended solids (TSS), zinc (Zn), and microplastics (MPs). MPs correlated positively with pH, E. coli, phosphate (PO43−), and nitrate nitrogen (NO3—N), and negatively with dissolved oxygen (DO) and iron (Fe), suggesting their role as vectors for nutrients and pathogens under oxygen-poor, biologically enriched conditions. Contaminant levels varied by land use and season, with higher concentrations on residential roads and winter peaks for COD, chloride (Cl−), Zn, Fe, and TSS. Ecological risk indices indicated very high metal risk, primarily from lead (Pb) and nickel (Ni), and moderate-to-high polymer risk from polyvinyl chloride (PVC) and polymethyl methacrylate (PMMA). These findings highlight road runoff as a key driver of urban water quality degradation, emphasizing the importance of managing first-flush discharges through land–use–specific controls, seasonally optimized street cleaning, and targeted treatment of high-risk contaminants.
Im Rahmen der Vorlesung Engineered Natural Treatment Systems (ENTS) von Benedikt Aumeier haben wir am Mittwoch 12.12.2025 die Kläranlage Irschenberg besucht. Dort passiert gerade einiges: Die Anlage wird von 5.000 auf 7.000 EW erweitert und erhält eine Stufe zur Spurenstoffelimination – umgesetzt als innovativer Vertikalfilter Biofilterplus.
Was steckt hinter dem Biofilterplus? Ein System, das nicht nur Spurenstoffe zuverlässig reduziert, sondern gleichzeitig als Ablaufpuffer dient. Kombiniert werden Sand (biologischer Spurenstoffabbau) und granulierte Aktivkohle (Adsorption). So wird der sensible Vorfluter vor der Belastung mit Spurenstoffen geschützt und Ablaufspitzen werden effektiv abgefangen.
Herr Schmidt, Leiter der Anlage, führte uns vom Zulauf bis zum Ablauf durch die Baustelle und teilte spannende technische Einblicke. Besonders im Fokus der Exkursion stand der neue Biofilterplus, an dessen Planung unser Lehrstuhl im Rahmen eines Promotionsprojekts beteiligt ist (Anna-Sonia Kau, Dr. Benedikt Aumeier, Prof. Jörg E. Drewes). Auch nach der Inbetriebnahme im Mai 2026 werden wir die Betriebsbegleitung für den Filter übernehmen. Der Biofilterplus wird eine der ersten Anlagen zur Spurenstoffelimination in Bayern sein. Das Projekt wird vom Bayerischen StMUV gefördert und soll als Blaupause für viele weitere kleine Kläranlagen dienen. Hier können Sie mehr zum Projekt erfahren.
Das Highlight für die Studierenden war der bereits fertig befüllte Filter – sie waren sichtlich beeindruckt, ein innovatives engineered natural treatment system so praxisnah zu erleben.
Vielen Dank an Herrn Schmidt für die großartige Unterstützung der Exkursion!