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Fertilizers play an irreplaceable role in agricultural production. In China, the use of chemical fertilizers is large but the fertilizer utilization efficiency is low. In order to ensure the sustainable development of agricultural production, controlled release fertilizers with high nutrient efficiency and environmental friendliness have received widespread attention. The controlled release fertilizers adopt polymer coating, which can quantitatively control the nutrient release amount and release period of the fertilizer, so that the nutrient supply is consistent with the law of fertilizer demand in each growth period of the crop, and the effect of saving fertilizer and increasing efficiency is significant. The nutrient release characteristics of coated fertilizers are closely related to the material and structure of the coating layer. In the process of discharging fertilizers, the discharging device will cause different degrees of mechanical damage to some fertilizers, resulting in damage to the coating layer and affecting the nutrient release characteristics. Therefore, it is of great significance to design a fertilizer discharging device suitable for non-destructive discharging of coated fertilizers. In order to ensure that the numerical simulation truly reflects the crushing of fertilizer particles, it is necessary to calibrate the parameters of the crushing model of coated fertilizer particles. The critical crushing displacement and critical crushing load of the coated fertilizer particles were obtained through uniaxial compression tests. With this as the goal, the Bonding model parameters were systematically calibrated, based on sequential tests (Placket-Burman test, Steepest ascent test and Box-Behnken test), and finally the optimal parameters combination was optimized. The uniaxial compression test was carried out again under the optimal parameters combination condition. The relative error of the critical crushing displacement and critical crushing load and the actual value were 0.222% and 0.554%, respectively. The observed qualitative and quantitative results of numerical and experimental approaches were in good agreement. Based on these results, comparing the actual and simulated fertilizer particle crushing in the fertilizer discharging process, it was obtained that the fertilizer particle crushing rate in the simulation was slightly higher than that of the actual situation. Overall, DEM modeling better reproduced the damage of fertilizer particles in the fertilizer discharger.