During the meeting (June 18, 2021) on alternative fertilizers at Houbraken in Bergeijk, the present arable and dairy farmers and Nutriman exchanged a lot of information. About the use and necessity of using fertilizers from various sources, about how to do that, about how to calculate how much of what and when and also about where you can get stuck (spoiler alert: regulations).
It is important to remember that (your own) slurry is an excellent basic fertiliser. N and P from innovative sources like manure processing, sewage sludge or ash can be interesting to add to the fertilizer supply. Jan Theuws gave a few calculation examples of how this works. These alternative fertilisers can help to reduce the dependence on chemical fertilisers and close the mineral cycle.
We saw how this works in practice in the trial field that Houbraken had set up. Among other things, mineral concentrate is used here, which comes from the manure processing plant installed by Houbraken. Using a belt filter press and reverse osmosis, the plant converts pig manure into an exportable thick fraction, a mineral concentrate that replaces chemical fertiliser, and clean water. And so we came to the obstacles in this story, because this trial is now exempt because it does not (yet) fit in the current manure legislation. While it does answer the call for more closed cycles. Finding out how you can benefit from alternative fertilisers is therefore not only a quest for farmers, but also for the policymakers in The Hague.