The Raw Materials Factory: high-tech developments

Raw materials are becoming scarce, so we need to think circularly and minimise waste. That is why the Dutch water boards are working in numerous ways to transform wastewater treatment plants into 'factories' where clean water, clean energy and valuable raw materials are produced. In doing so, they contribute to a cleaner, sustainable world. A world with as little waste as possible, and with as much clean energy and reusable raw materials as possible.

What is Nereda®?

Nereda® is a sustainable purification technology in which the purifying, active sludge does not form flakes, but granules. This makes the sludge settle much faster and easier. The technology has a high purification efficiency, takes up little space (no large settling tanks needed) and consumes relatively little energy.

The Nereda® technology is discovered by TU Delft. This technology was developed in collaboration with, among others, the water boards and STOWA and is currently being marketed worldwide by Royal Haskoning DHV.

There are more Nereda® treatment plants in the Netherlands, but they process household wastewater and do not yet have an extraction plant that processes industrial residual water like the one in Zutphen. The Vallei and Veluwe water board and other partners are working together on an installation that will also enable the extraction of these biopolymers from domestic wastewater. At Rhine and IJssel Water board and Vallei and Veluwe Water board full scale NEO-alginaat installations will eventually be built. They expect to save costs by processing a quarter less sludge and selling the raw material.

Kaumera Nereda® Gum

Researchers at the TU Delft discovered that a new type of raw material can be extracted from the sludge granules that form during the Nereda® purification process. This is a sustainable and improved purification technology in which the sludge that remains after purification does not form flakes, but quickly settable granules. A special biopolymer with multifunctional properties can be obtained from these granules: Kaumera Nereda® Gum (formerly neo-alginate).

A versatile name

Kaumera logo

Kaumera. It is a versatile name for a versatile product. Kaumera means 'chameleon' in Maori, the language of the original inhabitants of New Zealand. The chameleon is known for its colourful transformation and adaptability. This makes the chameleon a beautifully flexible, effective and versatile animal.

Infinite application possibilities

By combining Kaumera Nereda® Gum with another raw material, the character of the substance changes. Kaumera is an amplifier and connector of properties. For example as part of lightweight biocomposites. This ensures that the application possibilities are practically endless.

Kaumera can retain water but also repel it. This makes various applications possible, for example in agriculture, horticulture and the concrete industry. These include reducing the leaching of fertilisers in agriculture. As a result, crops absorb fertilisers better. They are more resilient and grow better. The water-repellent properties also make Kaumera an excellent coating for concrete floors.


The Rhine and IJssel Water Board, the Vallei and Veluwe Water Board, TU Delft, RoyalHaskoningDHV and the the Dutch Foundation for Applied Research in Water Management (STOWA) are working together on the extraction and marketing of this special biobased raw material with many practical, valuable application possibilities.

process household wastewater and do not yet have an extraction plant like the one in Zutphen. The Vallei and Veluwe water board and other partners are working together on an installation that will also enable the extraction of these biopolymers from domestic wastewater.

The raw material factory

For the Rhine and IJssel Water Board, the construction of the factory in Zutphen is a way to contribute to a sustainable, circular economy. Dijkgraaf Hein Pieper: 'Climate change requires a rapid transition to sustainable Netherlands: energy-neutral, circular and climate-proof. We must now take measures to achieve this. We do this by not only purifying waste water, but also recovering raw materials from it.

We and other water boards are therefore busy transforming our water treatment plants into energy and raw materials factories. The construction of the raw materials factory is made possible in part thanks to financial support from the province of Gelderland, the Ministry of Economic Affairs and Climate Change (DEI programme), and the EU (LIFE programme).

Provincie GelderlandRijksdienst voor Ondernemend NederlandLIFE

National Alginate Development Programme

The recovery of alginate-like biopolymers from wastewater takes place within the National Alginate Development Programme NAOP. In this programme, the Vallei and Veluwe Water Board, Rhine and IJssel Water Board, the Dutch Foundation for Applied Research in Water Management (STOWA), the RoyalHaskoningDHV engineering consultancy and Delft University of Technology work closely together.

All parties contribute part of the knowledge and expertise needed to recover, process and market the new raw material. From laboratory research to full scale recovery. In this way, the water board, the scientific community and the business community work together on a sustainable, circular economy.


The water treatment plant in Zutphen will be ready to treat FrieslandCampina's residual water in January 2019. The Nereda® treatment plant to produce the new raw material is scheduled for completion in the autumn of 2019. The factory in Zutphen is being built by the Rhine and IJssel Water Board. The Vallei and Veluwe Water Board is currently building a raw materials factory in Epe. There, purified sewage is used to produce Kaumera.


Rhine and IJssel Water Board

Rhine and IJssel Water Board
Treating waste water costs the Dutch water boards a considerable amount of money every year. Moreover, valuable energy and raw materials are often lost with this waste water. That is why the Rhine and IJssel Water Board, together with universities, knowledge institutes and companies, are working hard on the wastewater treatment of the future. A future in which water treatment plants will become real sustainability factories: Energy and raw materials factories that do not produce waste and are energy-neutral. In this way, we are increasingly working towards a fully circular economy.

Vallei and Veluwe Water Board
Vallei and Veluwe Water Board

Within the NAOP, the Vallei and Veluwe Water Board is a co-initiator. We see Kaumera Nereda® Gum as a potential raw material that can make a major contribution to our goal of full circularity by 2050. It shows that we Dutchmen are leaders in the field of water innovation. The development of the biobased polymer also offers the opportunity for considerable cost savings within the water boards. As a team we are therefore fully committed to research, production and sales of Kaumera. At Epe sewage treatment plant, we intend to build a Kaumera extraction installation to investigate the best way to extract the raw material from the communal sludge. As the Vallei and Veluwe Water Board, we are proud to be able to contribute to this promising development.

Royal HaskoningDHV
Royal HaskoningDHV

Royal HaskoningDHV has been a leading engineering company in consultancy and project management for more than 135 years. We are a global leader in innovation and sustainable development. Our 6,000 professionals work with clients, partners and knowledge institutions on smart solutions for future-proof cities, water, transport and industry. Together we work on projects that help customers use their resources more efficiently and contribute to a better society. That is our motive: enhancing society together.

Royal HaskoningDHV is the owner of the innovative Nereda® technology for wastewater treatment and applies this technology worldwide. The production of valuable biopolymers from Nereda® sludge strengthens the sustainable character of the technology. Within this development Royal HaskoningDHV, together with its partners, is on the bar to market the concept, process and product internationally.

Delft University of Technology (TU Delft)

Delft University of Technology

Alginate is currently extracted from seaweed. It is used to a limited extent in the medical world (denture mould, alginate plasters and cough medicine). By cleverly combining existing and new techniques, the raw material Kaumera Nereda® Gum, which shows similarities with alginate, can be extracted from sludge granules that form during the Nereda® purification process. Prof. Dr. Mark van Loosdrecht of TU Delft is the developer of this purification process. Yuemei Lin, assistant professor at Van Loosdrecht's group, discovered that the polymer in Nereda® sludge granules is mainly alginate. She is now exploring this further with PhD student Simon Felz (TU Delft). Prof. Stephen Picken and PhD student Jure Zlopasa are doing research into all kinds of applications of the alginate-like polymer in the field of materials. TU Delft, for example, has developed a concrete coating.

To protect concrete, polyester or another material from the oil industry is currently often used. This must be applied several times and is not degradable. The TU Delft coating is a natural product consisting of alginate, a substance extracted from algae, combined with tiny clay particles. The material is completely biodegradable and only needs to be applied once. The alginate coating reacts chemically with calcium in the concrete, immediately creating a waterproof layer.

The Foundation for Applied Research in Water Management (STOWA)


STOWA is the knowledge centre of regional water managers in the Netherlands. STOWA develops, gathers and disseminates the knowledge needed to properly carry out the challenges and tasks faced by water boards. Examples are climate change and energy efficiency. But also the recovery and recycling of raw materials from the water chain, such as biopolymer from sludge from Nereda® purification plants. With this in mind, STOWA has signed the Green Deal Raw Materials. You can find more information about us and our work at www.stowa.nl


Within the framework of the Energy and Raw Materials Factory, water boards, the business community and knowledge institutions work closely together to build the Kaumera Factory.

If you have any questions, please contact the Rhine and IJssel Water Board on telephone number 0314 369369.