Prof. Dr. Ir. Merle de Kreuk

Merle de Kreuk is Professor of Environmental Technology. She is viewed as an excellent researcher and a pioneer with an impressive track record in the field of environmental engineering. She specialises in waste water treatment and anaerobic digestion processes.

Waste treatment with aerobic granular sludge (Nereda technology)

De Kreuk has been internationally lauded for her prior work on the Nereda sewage treatment process. This technology requires 25% less energy and 75% less space to treat household waste water using aerobic granular sludge technology.

In part thanks to Merle’s PhD research (supervised by Professor Mark van Loosdrecht, TU Delft) and her efforts afterwards, aerobic granular sludge technology has developed into a fully functional environmental technology that is viewed as an important innovation in the field of waste water treatment. RoyalHaskoning DHV has built several waste water treatment plants around the world based on this technology.

Bioenergy & reuse

Nowadays she focusses on the (anaerobic) degradation of particulate substrates, such as waste activated sludge, in order to produce bioenergy, volatile fatty acids and nutrients from waste streams. She recognizes that increased knowledge on the conversion mechanisms of different components in the waste streams in detail, as well as attention for reactor design, will eventually lead to increased conversion efficiencies and better product recovery.

Furthermore, she leads a collaboration between Indian and Dutch universities and research institutes for the local treatment of sewage and healthy (water) reuse (LOTUS-HR), in which sewage is extracted from open sewars (drains) and treated to produce a water quality that can be used in the direct surroundings of this treatment plant.   


In 2016, Merle received an 800,000 euro VIDI grant to continue her research into aerobic granular sludge technology. Waste water treatment using this technology has proven very efficient, but how suspended particulate matter is removed from sewage and converted by aerobic granular sludge technology is as yet unknown. De Kreuk’s research combines advanced analysis and modelling techniques in order to comprehend mechanisms that influence conversion processes and granule morphology by suspended particulate matter.


Training new environmental engineers is of great importance to Merle de Kreuk. She was awarded in 2017 with an education fellowship from the TU Delft. At the moment she is the project leader of ProfEd (Professional Education Course) on Nereda aerobic granular sludge technology and she has been one of the establishers of the first Massive Open Online Courseware on sewage treatment, that she also uses for blended education in her on-campus courses.

De Kreuk accelerated the development of the new MSc track ‘Environmental Engineering’ at the Faculty of CEG. This new track - that started in September 2016 and of which de Kreuk is Master coordinator - has attracted the attention of a broad group of students both in the Netherlands and abroad. 

Merle de Kreuk