The influence of moisture on mechanical components for plant nursery substrate production
Paweł Tylek , Zdzisław Kaliniewicz , Mariusz Kormanek , Łukasz Mateusiak
AbstractThe constructions of equipment for the enrichment packaging and application of soil substrates are based on the experience of practitioners rather than the expertise whose source is the in-depth knowledge of the agrophysics of friable materials. Understanding the physical properties (especially mechanical ones) is necessary for the construction of containers, warehouses, silos, chutes, feeders, and the selection of the parameters of their work so that technological process run smoothly. Due to the above, the aim of the present study was to investigate the physical characteristics of friable components used in the production of nursery substrates, such as dolomite, perlite, vermiculite and the Osmocote fertilizer, depending on the level of humidity. An analysis of the granulometric composition and the descent mass was performed; and the values of external friction angles on different structural surfaces as well as the angles of natural repose and descent were determined. It was found that, generally, an increase in humidity did not significantly affect the value of the natural angles of repose of the examined friable materials. However, it significantly reduced their friability when descending. Perlite and vermiculite, being the materials with a high water content, needed about 50% moisture content for their descent angles to significantly increase. Small and sticky dolomite particles resulted in the occurrence of an almost square angle of natural descent already at 60% moisture. It was found that the values of the coefficient of external friction in friable materials depends on the kind of friction surface (structural surface), and to a lesser extent on moisture.
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.