Effect of process parameters on the crush strength of granular fertiliser

The granulation characteristics of nitro-phosphate-based NPK fertiliser have been investigated in a bench scale drum granulation unit. It was found that the granulation of the fertiliser took place in the growth regime. Crush strength analysis of the final granulate was undertaken and was correlated with particle size and fractional saturation. The experimental data and analysis in this study indicate that that the rounded, regular-shaped granules produced by granulating with higher liquid phase ratio and fractional saturation result in the granules having stronger bonds between sub-granules and lower porosity.