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.

Savremena poljoprivredna proizvodnja se ne može zamisliti bez primene đubriva, posebno sa aspekta boljeg korišćenja biološkog potencijala rodnosti gajenih biljaka. U radu je prikazan deo rezultata trogodišnjih ispitivanja tehničko-tehnološkog sistema aplikacije mineralnih đubriva različitim tipovima centrifugalnih rasipača. Jedan od ciljeva istraživanja bio je i određivanje fizičko-mehaničkih osobina različitih tipova mineralnih đubriva, njihovih promena tokom samog procesa aplikacije i njihovog uticaja na kvalitet same aplikacije. U istraživanje su uključena četiri tipa mineralnih đubriva i to UREA, KAN, MAP i NP. Dobijeni rezultati tokom ispitivanja fizičko-mehaničkih osobina primenjivanih mineralnih đubriva pokazuju da đubriva koja imaju najveći procenat granula prečnika između 3,3 mm i 4,75 mm imaju najveće uglove trenja i nasipanja, kao i dobru otpornost prema lomu granule. Vrednosti ugla trenja su značajno varirale u zavisnosti od tipa đubriva i mesta uzorkovanja. Najniža vrednost, 17,53o je zabeležena kod UREE nakon aplikacije a najviša, 24,37o kod đubriva MAP iz skladišta na imanju. Vrednosti statičkog ugla nasipanja su takođe statistički značajno varirale u zavisnosti od tipa đubriva i mesta uzorkovanja. Najniža vrednost, 30,34o, je zabeležena kod đubriva MAP nakon aplikacije a najviša, 36,91o, je zabeležena kod NP đubirva iz skladišta. NP đubrivo je pokazalo i najviše vrednosti dinamičkog ulga trenja. Najniže vrednosti ovog parametra, 23,35o, imalo je đubrivo UREA. Čvrstoća granula je varirala u zavisnosti od tipa đubriva i od mesta uzorkovanja. Najviše vrednosti su zabeležene kod đubriva NP u svim fazama manipulacije dok su najniže vrednosti zabeležene kod đubriva UREA.