When it comes to fertilizers, one of the most widely used fertilizers is nitrogen.
Nitrogen comes in various forms. The fertilising power of nitrogen varies according to the form in which it is present, the types of crops to which it is applied. As well as the state of the soil, (e.g. level of compaction). Nitrogen in slurry is of interest as it is a natural source of readily available fertiliser (between 2.7 and 4.9 kg per tonne of slurry from fattening pigs).
Organic and mineral nitrogen
To make a schematic distinction between organic nitrogen and mineral nitrogen.
Nitrogen contained in slurries, for example, is in organic and ammoniacal form. It is in a captive state in the fibre structure. Before being accessible to plants, the organic fraction must be mineralized. A distinction is then made between two types of mineral nitrogen. The ammoniacal form and the nitrate form. The ammoniacal form is transformed into nitrate by the action of the nitrifying bacteria and can thus be better absorbed by the plants. Nitrogen in its ammoniacal form is therefore a fertilizer of choice, unlike organic nitrogen, whose mineralization rate varies according to its carbon ratio (C/N), which is determined by the carbon-nitrogen ratio present in the manure under consideration, and by soil temperature. In addition, the nutrient concentration level of organic fertilizers is much lower than that of mineral fertilizers, so they must be applied in larger quantities.
The Solugen process
Let us remember that the Solugen process makes the following available at the end of the slurry treatment process:
– A solid residue rich in phosphorus (85% of the phosphorus initially contained in the manure) and organic nitrogen.
– A large volume of pure water (84% of the volume of manure).
– A potassium concentrate (4.5% of the volume of manure)
– A bio-liquid rich in ammoniacal nitrogen (1.5% of the volume of manure)
The commercial potential can be very interesting. Indeed, a pig farm that would treat 10,000 m3 of manure per year would obtain, among others, 150 m3 of bio-liquid rich in ammoniacal nitrogen.
Solugen recently mandated a research organization to validate the concentration level of these bio fertilizers, particularly ammoniacal nitrogen, their degree of safety, their fertilizing power, as well as the methods recommended for their use.