Grote Waternavel comes second in BlueCity's Circular Challenge
Wednesday evening, April 6, was the final of BlueCity's Circular Challenge. Six teams presented a new, circular prototype that they had developed using a water-related waste stream from one of the participating organizations. The winning team will have the opportunity to further develop the product and make use of Blue City's facilities.
In the circular challenge, you can submit a problem for which you would like to find a circular solution. The Noorderzijlvest Water Authority participated with the large water pennywort and ultimately came in second.
Why the big water pennywort?
Our waterways are plagued by exotic species. These are plants that do not belong here and behave invasively. This means that they overgrow other species and grow rapidly, causing problems for biodiversity and water flow. The giant hogweed is one such plant. We are now removing this plant from our waterways and placing it on the banks. Normally, the plant debris goes to a waste processor to be incinerated, which currently costs a lot of money and fuel. In the context of circularity, it would be great to be able to process this plant into something reusable.
Students got to work
A group of four students set to work on the large water pennywort submitted by Noorderzijlvest. Under the guidance of pioneers from the BlueCity network, the students were given six weeks to develop a scalable product from a water-related waste stream. The students came up with compeat, the first sustainable potting soil. They set to work on the peat-free growing medium solution. First, they compost, dry, and grind the giant water pennywort so that the plant cannot grow back. This makes it a good substitute for potting soil. To make normal potting soil, entire peat bogs are excavated in places such as Latvia. They then mix our material with other biobased waste material to create sustainable potting soil.
Second place
Unfortunately, the giant water pennywort did not win and we ended up in second place. The Noorderzijlvest Water Authority will work with the students to explore how we can proceed with the developed product. First place went to modular walls made from Asian knotweed, submitted by the Schieland en de Krimpenerwaard Water Authority.
Participating organizations
A total of six organizations participated. Prototypes from the following waste streams were presented during the final on April 6:
- Asian knotweed - Schieland and Krimpenerwaard Water Board
- Hardwood - Rijnland Water Authority
- Bubble aerators - Hollandse Delta Water Authority
- Dredged material - Province of Gelderland
- Tangled hair - Brabantse Delta Water Authority
- Great water pennywort - Noorderzijlvest Water Authority
About the Circular Challenge
With the Circular Challenge, BlueCity offers established organizations the opportunity to become acquainted with the circular economy by developing a scalable product from their own waste stream within six weeks. Under the guidance of pioneers from the BlueCity network, a team of young professionals develops a business case and a tangible prototype.