At one time, the costs of disposing residual waste streams from the Vitens’ drinking water facilities amounted to approximately 1.8 million euros a year. Consequently, Vitens came up with a new approach by process optimization and upcycling to reuse these materials productively that is not only worthwhile commercially, but environmentally too.
Vitens produces 350 million m3 drinking water annually for 5,6 million customers in the Netherlands. The production also results in 60,000 tons of byproducts, such as calcium, iron and humic acid, which are expensive to separate. In 2012, Vitens set itself the goal to ensure valuable, cost-effective and sustainable use of these residual flows.
Putting byproducts to good use
Detailed studies, in collaboration with the University of Wageningen, RoyalHaskoning DHV and others, showed that these byproducts could be used effectively in other sectors and could be sold at a profit. Vitens developed a production method whereby its humic acid could be put to use as a high-quality soil improver. This made Vitens one of the largest humic acid producers of Europe. In addition, applications have been developed for animal nutrition. As a result, Vitens now also produces for the agriculture and animal feed sector.
As these streams contribute to sustainable agriculture, the new valorisation approach also results in cleaner groundwater. Now that Vitens can produce such natural soil improvers as humic acid and chalk pellets, it is able to cooperate productively with farmers, with whom it shares the same catchment area. It’s a win-win for both: better crop yields and high quality groundwater.
The Best Practices
Holland Circular Hotspot (HCH) wants to support international cooperation on the circular economy, with the aim of creating business opportunities and promoting the exchange of knowledge and innovation. In the magazine Circular Is Going Global - Join Holland's Flow you can read which circular best practices the Netherlands has to offer.