Kaumera Nereda® Gum: from waste to a valuable raw material

In a circular water economy wastewater will no longer exist. Kaumera Nereda® gum is a new bio-based raw material which is produced from aerobic granular sludge originated from the Nereda® wastewater treatment process. Kaumera can be used as a bio-based alternative for which nowadays a variety of petrochemical resources is used. With aerobic granular sludge being implemented globally for treatment of various types of wastewater, Kaumera is potentially a valuable resource.

Since 2013, lab research and pilot experiments on Kaumera production were done with a consortium consisting of water authorities, business support (technology supply, upcycling and business development) and a knowledge institute, having the complete value chain in scope.

Kaumera extraction factory Zutphen

The world’s first extraction factory for Kaumera was opened on October 2, 2019 in Zutphen. This factory consists of a Nereda® wastewater treatment plant and a Kaumera extraction installation. This installation is the world’s first full-scale production unit based on an industrial wastewater flow, followed in spring 2020 with the first municipal production unit in Epe, based on municipal wastewater.


Kaumera is a versatile raw material: it can repel and absorb water and it is fire retardant. It is also very suitable for coatings and composite materials. By combining it with other raw materials, like clay and cellulose, the character of the fabric changes. Hence the name Kaumera, which means ‘chameleon’ in Maori.

So far, research and tests were done successfully using Kaumera as coating material for fertilizer and paper, current agent for concrete, bio-stimulant, as basis for bio-nano composite materials and even as fire retardant binder. This makes it for instance valuable for use in agriculture, building sector, textile and paper industry. In terms of circular impact, the use of Kaumera as a bio-based alternative decreases the amount of fossil resources and first-generation biomass needed.

Using Kaumera from aerobic granular sludge is a big step towards circular use of raw materials from wastewater.

Award winning

Due to its multidimensional applications, Kaumera Nereda® Gum was both nominated, and won the overall title in the 2019 Aquatech Innovation Awards. The awards are designed to recognise world-class innovation and technologies that have the potential to disrupt the global water market. Kaumera was shortlisted amongst 12 other innovative technologies, which were selected from an impressive number of entries by an expert jury in the lead up to the flagship Aquatech Amsterdam event.

René Noppeney, the Global Director of Water Technology Products & Innovation at Royal HaskoningDHV said in response to the win, “This award was a testament to the huge positive impact Kaumera will have on the circular economy. We were genuinely thrilled to receive this accolade. It is an environmentally and economically beneficial product which will help to secure the future through minimizing waste and promoting waste reuse.”

In December 2019 the Kaumera project in Zutphen also won the Water Innovation Prize, an initiative of the the Association of Dutch Water Authorities and the Nederlandse Waterschapsbank N.V.

The Kaumera extraction from Nereda® aerobic granular sludge

Laboratory and pilot experiments showed that circa 30% of the volatile solids in excess Nereda® sludge can be extracted as Kaumera Nereda® Gum. The extraction of Kaumera from sludge to the water phase takes place under alkaline conditions at high temperature. The residual sludge is separated by centrifugation from the water containing and dissolved Kaumera. The precipitation of the solubilised material at low pH results in a gel like material containing 5-12% TS. The Kaumera gel is separated from the water phase in the last step by centrifugation.

The Kaumera extraction reduces excess sludge that requires final disposal by approximately 25%.

There is a need for a transition in the waste water treatment process, from a process that handles waste towards the production of valuable raw materials. Kaumera is one of the potential valuable raw-materials originated from the waste water treatment process. By showing that it is both technically feasible and economically viable, we aim to boost the shift to a circular water economy.

Important milestone, first commercial delivery of Kaumera

On March 12 an important milestone was obtained because the first truck with 20 m3 Kaumera left the factory in Zutphen. This will be processed by Koppert Biological Systems for use as a biostimulant in a farm. In a few weeks, the partners have worked closely together to produce the Kaumera in the right specifications and prepared it for transport.


This innovation is the result of intensive collaboration between TU Delft, Royal HaskoningDHV, Stichting Toegepast Onderzoek Waterbeheer (STOWA), Water Authorities Vallei en Veluwe and Rijn en IJssel and ChainCraft. Each partner has contributed part of the knowledge and expertise for researching, developing, producing and marketing this raw material.

Contact us

If you have any questions or comments, please contact Véronique Renard of RHDHV, Phone +31 610 992113 or info@kaumera.com. Visit www.kaumera.com.