Floating pennywort comes second in BlueCity's Circular Challenge
The final of BlueCity’s Circular Challenge took place on Wednesday evening, April 6. Six teams presented a new circular prototype 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 BlueCity’s facilities.
In the Circular Challenge, you can submit a problem for which you’d like to find a circular solution. Noorderzijlvest Water Authority the competition with the giant hogweed and ultimately took second place.
Why floating pennywort?
Our watercourses plagued by invasive species. These are plants that are not native to this area and behave invasively. This means they outcompete other species and grow rapidly, causing problems for biodiversity and water flow. The giant water pennywort is one such plant. We are currently removing this plant from our watercourses placing it on the banks. Normally, the plant debris is sent to a waste processor to be incinerated, which currently costs a great deal of money and fuel. In the spirit of circularity, it would be ideal to be able to process this plant into something reusable.
The students got to work
A group of four students set to work on the giant 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. To do this, they first compost, dry, and grind the giant water pennywort, preventing the plant from regrowing. Afterward, it serves as a good substitute for potting soil. To produce conventional potting soil, entire peatlands are excavated in places like Latvia. They then mix our material with other bio-based waste materials to create sustainable potting soil.
Second place
Unfortunately, the giant water pennywort didn’t win, and we ended up in second place. Noorderzijlvest Water Authority work with the students to explore how to move forward with the product we developed. First place went to modular walls made from Asian knotweed, submitted by the Schieland and Krimpenerwaard Water Board.
Participating organizations
A total of six organizations participated. Prototypes made from the following waste streams were presented during the finals on April 6:
- Asian knotweed - Schieland and Krimpenerwaard Water Board
- Hardwood - Rijnland Water Board
- Bubble aerators - Hollandse Delta Water Authority
- Dredged material - Province of Gelderland
- Kluwen Hair - Brabantse Delta Water Board
- Common water pennywort -Noorderzijlvest Water Authority
About the Circular Challenge
Through the Circular Challenge, BlueCity offers established organizations the opportunity to explore the circular economy by developing a scalable product from their own waste stream within six weeks. Under the guidance of pioneers from BlueCity’s network, a team of young professionals develops a business case and a tangible prototype.