DETERMINATION OF FRICTION COEFFICIENTS OF FAST-GROWING TREE BIOMASS

Abstract

The development of civilization, population growth and technological development cause an increasing energy demand. Solid biofuels have particular importance in the energy sector. The enormous potential of biomass in Poland is agriculture with related possibilities of setting up fast growing plantations, which have attracted attention of potential growers for the past years. One of the most important phenomena occurring in most processes of mechanical processing of biomass is the phenomenon of friction. The purpose of the work was to determine the coefficient of external friction (static and kinetic) of crushed shoots of robinia pseudoacacia and alder. Coefficients of friction were determined with different granulation of material and humidity. The prepared samples were subjected to friction tests on a steel surface. Analyzing the obtained results, it can be concluded that with the increase in the length of chips, marked coefficients of friction, both static and dynamic, increase. In the case of alder wood chips, the static friction coefficients (μS) ranged from 0.3- 0.71. However, the sliding friction coefficient (μK) ranged 0.24-0.63. The values obtained for the robinia acacia chips are in a similar range (μS = 0.36-0.7, μK = 0.27-0.64).