Department Process Engineering

AK24Water  - Use of activated carbons (GAC/PAC) in a combined process

Eawag tested various processes for the elimination of micropollutants at the semi-technical and full-scale level at the Glarnerland WWTP over four years between 2017 and 2020 (report).

Following the implementation of granular activated carbon (GAC) filtration (commissioned in mid-2023) and the option of additionally dosing powdered activated carbon (PAC) into the biological treatment, Eawag is now supporting the operation of the processes with a monitoring program and specific individual studies. The Glarnerland wastewater treatment plant is the first plant to combine GAC filtration with pre-dosed PAC in the biological treatment.

The AK24Water project aims to gather and consolidate experience on the operation of GAC filters. Measurements of SAC, MV, and DOC of individual cells during dry weather are used to estimate when the average quality target of 80% MP removal in parallel-operated filter cells at the plant's effluent will fall below the threshold.

To define a final cutoff criterion for the replacement of individual GAC cells, the interaction with the PAC stage will be considered. Based on the identified dependencies in the datasets and time series, strategies will be developed in collaboration with project partners for optimal GAC loading (filter regime), the optimal GAC type, and PAC dosing to mitigate GAC performance losses during wet weather inflows (diluted wastewater matrix).

Another focus is comparing the efficiency of different GAC types used in the two treatment lanes of the wastewater treatment plant."

Publications

Böhler, M. A.; Joss, A.; McArdell, C. S. (2022) GAK-Filter für die Spurenstoffentfernung. Erfahrungen und Betriebsergebnisse der Pilotstudien ARA Furt/Bülach und Glarnerland, Aqua & Gas, 102(1), 48-54, Institutional Repository
McArdell, C. S.; Böhler, M.; Hernandez, A.; Oltramare, C.; Büeler, A.; Siegrist, H. (2020) Pilotversuche zur erweiterten Abwasser-behandlung mit granulierter Aktivkohle (GAK) und kombiniert mit Teilozonung (O3/GAK) auf der ARA Glarnerland (AVG). Ergänzende Untersuchungen zur PAK-Dosierung in die biologische Stufe mit S::Select®-Verfahren in Kom, 146 p, Institutional Repository
Böhler, M.; Hernandez, A.; McArdell, C. S.; Siegrist, H.; Joss, A.; Baggenstos, M. (2020) Elimination von Spurenstoffen durch granulierte Aktivkohle-Filtration (GAK). Grosstechnische Untersuchungen auf der ARA Furt, Bülach. Schlussbericht, 135 p, Institutional Repository
Böhler, M.; Joss, A.; McArdell, C.; Meier, A. (2020) Hinweise zur Planung und Auslegung von diskontinuierlich gespülten GAK-Filtern zur Elimination organischer Spurenstoffe aus kommunalem Abwasser. Konsenspapier zum Ergebnis des Workshops vom 9.12.2019 an der Eawag, 5 p, Institutional Repository

Project management / Contact

Marc Böhler Application and Development Tel. +41 58 765 5379 Send Mail
Dr. Christa McArdell Senior scientist / group leader Tel. +41 58 765 5483 Send Mail

Project duration

The project duration is around 3 years. Start January 2024

Financing

Wastewater Association Glarnerland, AVG

Partners

Wastewater Association Glarnerland (AVG), Bilten,

Engineering company HunzikerBetatech AG, Winterthur