Can you recycle Grodan stone wool?
Absolutely! The same properties that make stone wool such an effective growing media for cultivators actually make the material attractive for recycling markets.
Grodan recycling accounts for almost 60% of total ROCKWOOL recycling. Grodan products are recycled differently, though. This is because the Grodan stone wool products used have a different composition to ROCKWOOL stone wool products.
So how do we do that?
Grodan stone wool has several secondary applications including: feedstock for brick manufacturers, compost, stone wool and green roofs. We are always looking for new & innovative recycling solutions and new recycling providers.
From old to new. Circular solutions
ROCKWOOL's Rockcycle® program is a circular economy solution for the Netherlands and Denmark, which brings used stone wool back to factories so it can be re-manufactured into new stone wool products. Grodan stone wool can contain up to 75% recycled materials.
Clay for bricks
Used stone wool is a desired feedstock for brick manufacturers. Less energy is required to produce the finished bricks in the manufacturing process and the stone wool fibres add strength to the finished products.
Compost & Potting Mix
Compost is one of the main recycling applications for the North American market, where used stone wool is treated as a beneficial use amendment. The stone wool adds porosity, added water holding capacity, and additional nutrients.
Used stone wool is processed and bagged to create erosion control devices or “waddles.” The stone wool is an alternative media to sand and straw. Grodan is presently collaborating with a recycler to commercialise this option for different markets.
Processed used stone wool has shown to meet FLL Green Roof Guidelines. Stone wool’s natural water holding capacity is an ideal additive to green roof substrate brands.
We are constantly innovating and exploring for newer and better applications as we strive to make stone wool the most recycled product in the world. A few examples: wastewater filtration, expanding green roof applications, and soil for cowsheds & trotting tracks.
9,600 full trucks a year
As part of its commitment to the circular economy, Grodan has established a network of recycling facilities that accept, process, and recycle over 9,600 full truckloads of stone wool across North America, Europe, Asia and Australia. More than half of Grodan stone wool growers participate in recycling every year. Grodan’s recycling managers support growers by finding and building new recycling markets.
Used rock wool at a depot in the Netherlands
How about the future?
ROCKWOOL International is committed to sustainability, especially circularity. This means we are working on the following expansions and improvements:
- Offering recycling services in even more countries
- Collaborating with new recyclers to provide localised solutions
- Assisting growers in helping meet their specific recycling challenges
- Develop products that are even easier to recycle and reuse