Another prize for breakthrough AGS technology developed by TU Delft researchers

Aerobic Granular Sludge technology, which saves 30% on energy costs while removing nitrogen and phosphorus, has become a global success for its users. Developed by TU Delft’s world-renowned scientists Mark van Loosdrecht and Merle de Kreuk in partnership with RoyalHaskoningDHV, this technology has once again been recognised as a game-changing solution for wastewater treatment. 

Aerobic Granular Sludge (AGS), also known by its trade name Nereda®, purifies wastewater that is produced by industries or residents in urban and rural areas. The technology uses bacterial granules: the microorganisms in the granule remove the pollutants from the wastewater, to make it suitable for discharge on surface water or direct water reuse in agriculture. Compared to conventional wastewater technologies, AGS improves environmental compliance and robustness, achieving a reduction in a treatment plant’s footprint, lower investment costs, less energy use and reduced chemical consumption. 

Multiple prize winner

Hailed in 2020 as the ‘Best water technology breakthrough of the past decade’ by the Global Water Intelligence (GWI), this ground breaking innovation by TU Delft’s researchers and online instructors Mark van Loosdrecht (chair professor in Environmental Biotechnology) and Merle de Kreuk (professor Environmental Technology) has won public recognition several times.

It was awarded, amongst others, the Stockholm Water Prize 2018, the Wastewater Project of the Year - Global Water Awards 2019 and, most recently in 2021 the De Vernufteling prize. The latter is organized annually by the national trade association Koninklijke NLengineers and the De Ingenieur magazine and is considered the most prestigious award for Dutch engineering firms.

This year, van Loosdrecht received the 2022 Novozymes Prize for his pioneering work in copying and reusing nature’s mechanisms in wastewater treatment and resource recovery. The Novozymes Prize, awarded by the Novo Nordisk Foundation, recognises outstanding research or technology contributions that benefit the development of biotechnological science for innovative solutions.

De Kreuk and van Loosdrecht were also awarded the Simon Stevin Prize – the Dutch highest recognition for research with societal impact– in 2007 and 2013 respectively.

What makes it such a success?

One of the key aspects of this innovative technology comes from the formation of granular sludge under aerobic, or oxygen-rich, conditions. These ‘aerobic granules’ are able to remove contaminants from wastewater more efficiently than the flocculent sludge that is used in conventional treatment plants.  This formation of aerobic granular sludge was achieved by the TU Delft researchers through a special alternating ‘feeding regime’ (feast & famine), whereby the microorganisms end up storing reserves and form compact aggregates (i.e. no longer flocs). The advantage of having granules is that these settle faster, which makes the separation of the active biomass (microorganisms) and the cleaned water more efficient than in flocculent sludge systems.

The wastewater treatment can be carried out as a sequencing batch process in one reactor. There is no need to pump large recycle flows between different tanks as in the conventional flocculent sludge treatment systems. The efficient conversion process of aerobic granular sludge, in combination with this one tank processes, leads to about 30% reduction in energy consumption, and to a much smaller footprint by the treatment plant.

"Teaching about AGS technology is very inspiring"

In 2020, De Kreuk and van Loosdrecht developed and launched an online course for water professionals (engineers or consultants) from the industry – technologists, innovators, policy makers and anyone interested in gaining in-depth knowledge of AGS. The course shows how the technology works – among others by visiting a functioning treatment plant through VR, and via interviews with AGS technology users. Participants get to understand the underlying processes and learn how to implement them. The course team answers questions and shares experiences with the patented AGS technology, which is currently being installed at wastewater treatment plants all over the world. 
“Teaching online learners from all over the world about AGS technology is very inspiring - it will bring the technology further. Hopefully, new applications will arise from the learners’ creative minds”, says de Kreuk. 

“The AGS technology is relatively novel. The course helps to get rapidly updated and I trust it will inspire participants on how they can have bacteria work for them”, adds van Loosdrecht.

Andreas Giesen, Director of Technology at Royal HaskoningDHV – the international engineering and project management consultancy with which the technology was co-developed, says: “AGS has rapidly developed into a proven, new modern standard for cost-efficient and sustainable treatment of wastewater. This long-awaited course by TU Delft is the first that offers deep insights into the fundamentals and design of this game-changing technology –and is directly tutored by the original inventors.” 

When I saw the statement announcing AGS technology as the best tech breakthrough of the past decade, I couldn't resist knowing more about it.

Stephen Roberts, online course participant

Like Roberts, many professionals around the world are interested in learning how to apply AGS to “decrease the energy footprint and simplify the removal of biological nutrients”. The Aerobic Granular Sludge Technology for Wastewater Treatment online course provides exactly that: a practical way to keep pace with a leading technology of the future and a means to positively impact our planet sustainability.

Professionally accredited

It is not only the technology that is publicly recognised, but also the online course dedicated to spreading its knowledge and impact. The innovative course is accredited by the Chartered Institution of Water and Environmental Management (CIWEM) and thus allows delegates to receive up to 40 CIWEM CPD credits, which can be used towards professional recognition and Chartered status applications.

To find out more about the course and to register, visit the Aerobic Granular Sludge Technology for Wastewater Treatment page – next start date 13 April.

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