| abstract |
The present invention relates to a process for the continuous production of fertilizers in the form of granules, comprising the following steps: a) a mixture comprising lignite, magnesia, at least one nutritive compound chosen from the compounds nitrogen-based nutrients, phosphorus-based nutrients, potassium-based nutrients, nutrients based on carbon chains of plant and / or animal origin and mixtures thereof, and recycled granules of step e °), - b °) is carried out a granulation in an acid medium in the presence of water, superheated steam, sulfuric acid and the mixture obtained in a) to obtain granules having a rate moisture content ranging from 3 to 19% by weight, relative to the weight of the granules, - c °) the granules obtained in b) are dried up to a humidity level of 0.1 at 15% by weight, based on the weight of the granules, alise sieving of the granules and a separation of the granules, - e °) is carried out recycling in step a °) oversized granules, preferably after milling, and the granules under dimensioned. The invention also relates to a fertilizing material in form that can be obtained according to this process. |