Method for obtaining a urea-based fertilizer composition comprising a (thio)phosphoric acid triamide urease inhibitor via providing a liquid or solid premix with specific weight ratios

Abstract

Method for obtaining a fertilizer composition comprising (iii) at least one urea-containing fertilizer (1); and (iv) at least one (thio)phosphoric acid triamide (2) according to general formula (I) wherein Xis O or S; Ris C-C-alkyl, C-C-cycloalkyl, C-C-aryl, C-C-aryl-C-C-alkyl, or C-C-(di)alylaminocarbonyl; Ris H, C-C-alkyl, C-C-cycloalkyl, C-C-aryl, C-C-aryl-C-C-alkyl, or C-C-(di)alkylaminocarbonyl; or Rand Rtogether with the nitrogen atom linking them define a 5- or 6-membered saturated or unsaturated heterocyclic radical, which optionally comprises 1 or 2 further heteroatoms selected from the group consisting of N, O, and S; and R, R, R, and Rare independently of each other selected from the group consisting of H and C-C-alkyl; comprising the steps: a) providing a solid and/or liquid premix (P) wherein the premix (P) comprises at least one urea-containing fertilizer (1) and at least one (thio)phosphoric acid triamide (2) in a weight ratio of 1:6 to 400:1 based on the total weight of all urea-containing fertilizers (1) and of all (thio)phosphoric acid triamides (2), wherein at least 85 wt % of the premix (P) (a1) is not a melt; and (a2) is not obtained via melting of any of the at least one urea-containing fertilizer (1) or melting of any of the at least one (thio)phosphoric acid triamide (2); and (a3) is not obtained via dissolving or mixing the at least one (thio)phosphoric acid tri-amide (2) in/with a solvent (S) having a boiling point of less than 100° C., and b) adding the premix (P) to a melt (Q) comprising urea-containing fertilizer (1) by forming a mixture (M) n comprising the at least one urea-containing fertilizer (1) and the at least one (thio)phosphoric acid triamide (2), wherein the residence time of the thus formed mixture (M) before granulation is adjusted such that the at least one (thio)phosphoric acid tri-amide (2) is not or almost not decomposed in the mixture (M); and c) forming solid fertilizer granules by use of the mixture (M) comprising the at least one urea-containing fertilizer (1) and the at least one (thio)phosphoric acid triamide (2).