Effects of the application system on the physical and mechanical properties of mineral fertilizers

Abstract

Mineral fertilizers have a pivotal role in contemporary agricultural production, especially when seeking to exploit the full biological potential of crops. This paper presents the results of a three-year experiment on the distribution uniformity of different mineral fertilizer application systems. One of the objectives in this study was to define the physical and mechanical properties of four different types of mineral fertilizers and examine their changes during storage, transportation and application. A total of four fertilizers were taken into account: UREA, CAN, MAP and NP. The main physical properties, i.e. particle size, particle size distribution, friction coefficient, angle of repose and particle resistance, were analyzed on samples collected from the storage, the trailer (prior to application) and the field (after application). The results obtained show that fertilizers with a particle size distribution of 3.3 to 4.75 mm exhibit higher values of the angle of repose, friction and resistance. The lowest value of the angle of friction (17.53 0) was observed in the UREA fertilizer after application, whereas the highest angle of friction (24.37 0) was measured in the MAP fertilizer obtained from the storage. The values of the static repose angle varied depending on the fertilizer type and the place of sampling (storage, trailer or field). The lowest value of the static repose angle (30.34 0) was measured in the MAP fertilizer after application, whereas the highest static repose angle (36.91 0) was measured in the NP fertilizer from the storage. The NP fertilizer exhibited the highest value of the dynamic friction angle, whereas the lowest value of the dynamic friction angle was calculated for the UREA fertilizer. The NP fertilizer particles showed the highest resistance, whereas the UREA fertilizer particles were most susceptible to breakage.

Keywords

• mineral fertilizers
• physical properties
• storage
• centrifugal spreaders