A novel development that uses air and electricity to boost the nitrogen content of slurry and digestate could help farmers reduce nutrient losses and improve crop performance.

Developed by Norwegian agrotech firm N2 Applied, the scaleable on-farm process aims to create an efficient and sustainable fertiliser that reduces reliance on artificial inputs and improves accuracy of slurry applications.

In fact, trial data from international testing sites revealed that a winter wheat crop treated with N2 dairy slurry outperformed characteristics of ammonium nitrate-based fertilisers, with greater levels of nitrogen available to the crop.

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At a time when fertiliser prices have soared to all-time highs and growers are actively looking to improve soil health, manures offer a natural way to increase organic matter levels and provide crops with a range of valuable nutrients, while trimming back on costs.

However, the uniformity of muck can be a challenge to deal with, as nitrogen content varies considerably and losses to the environment can be significant.

Using the scientific technique that applies just air and electricity to slurry, the N2 process enriches liquid manure through a plasma conversion process that “locks in” nitrogen from the air.

This, in turn, increases the nitrogen content of slurry and provides crops with a greater level of plant-available nitrogen, while also reducing both methane and ammonia emissions.

The result is a nitrogen-enriched manure, which has the same characteristics as normal slurry, but can be used more precisely and delivers a significantly improved environmental footprint.

The tech units are powered by electricity, with most of that energy consumed by the plasma torch that is central to the conversion process.  

Trial data

In a winter wheat crop assessment run by Oxford Agricultural Trials in Goole, East Yorkshire, the wheat crop treated with nutrient-enriched manure was found to use the equivalent of 85% of the crop-available nitrogen applied to the fields via that of N2 Applied.

This was 27% higher than in the crop treated with ammonium nitrate, which used the equivalent of 58% of crop-available nitrogen, while the untreated dairy slurry used 53%.

Carl Hansson, chief executive officer of the firm, explains that these results are a dramatic breakthrough for food production.

“This technology has the potential to vastly diminish farmers’ reliance on chemical fertilisers, at a time when the cost of them has become crippling for some and the war in Ukraine has restricted supply,” he says.