Research in Agricultural Engineering, 2012 (vol. 58), issue 1

Experimental testing of some types of biologically degradable materials for processing in the SBM mechanical plant for hydrothermal treatment

P. Junga, E. Krčálová, K. Somerlíková, J. Mareček

Res. Agr. Eng., 2012, 58(1):1-8 | DOI: 10.17221/30/2011-RAE  

The SBM (stabiliser of biomass) mechanical plant model is designed for the hydrothermal treatment of biologically degradable materials with using the principle of thermal hydrolysis. The primary task of this equipment is to subject biologically degradable materials to hydrothermal treatment and to recover the materials for a further use or to eliminate them. These entities could use the mechanical plant for economic and environment-friendly methods of handling biologically degradable wastes or materials. The objective of the experiment with various types of biologically degradable materials was to establish the level for the transformation of input...

Impact of different harvest times on ash fusibility of energy grasses

P. Hutla, P. Jevič, Z. Strašil, J. Kočica

Res. Agr. Eng., 2012, 58(1):9-15 | DOI: 10.17221/29/2011-RAE  

Five different energy grass plants (reed canary grass, tall fescue, orchardgrass, tall oatgrass, red top) were identified and studied for the purpose of determining the fuel energy qualities of the plants' mass while focusing on ash fusion temperatures. The plants were cultivated on four different locations and harvested in various times of the year (early summer, autumn and spring of the following year). It was found that the ash fusion temperatures of plants harvested in early summer were substantially lower in comparison with the autumn and spring harvest. The analysis of the composition of the ashes gathered from samples of grass plants harvested...

Drying of cherry tree chips in the experimental biomass dryer with solar collector

T. Ivanova, B. Havrland, P. Hutla, A. Muntean

Res. Agr. Eng., 2012, 58(1):16-23 | DOI: 10.17221/10/2011-RAE  

Drying significantly influences the process of a biomass conversion into the renewable energy source as well as quality of solid biofuels (briquettes, pellets). The research is focused on monitoring and evaluation of the drying process in the case of cherry tree chips drying in experimental biomass dryer with solar collector. The dryer has been conceived as a result of the project which was realized at the State Agrarian University of Moldova. Technological and construction specifics of the biomass dryer are described in the paper. The moisture content of the cherry tree chips was observed in dependence of the drying time and at different locations...

Mechanical behaviour of several layers of selected plant seeds under compression loading

D. Herák, A. Kabutey, A. Sedláček, G. Gűrdil

Res. Agr. Eng., 2012, 58(1):24-29 | DOI: 10.17221/11/2010-RAE  

This article is focused on the determination of the mechanical behaviour of several layers of plant seeds namely; garden pea (Pisum sativum L.), common bean (Phaseolus vulgaris L.), common sunflower (Helianthus annuus L.) and jatropha (Jatropha curcas L.) seeds under compression loading. The results from the experiment showed that during compression plant seeds may change their mechanical behaviour that is deformation characteristic ceases to be a function of growing and beginning to resemble that of trigonometric functions and this behaviour is called the "wave effect". Also the strain value at which there...

Quality evaluation of briquettes made from wood waste

M. Brožek, A. Nováková, M. Kolářová

Res. Agr. Eng., 2012, 58(1):30-35 | DOI: 10.17221/33/2011-RAE  

At logging and at the subsequent wood and wood semi-products treatment the fine grained loose waste arises, e.g. wood dust, saw dust, shavings, chips, bark etc. One of possibilities of its meaningful utilization is the briquetting technology, products of which are briquettes determined for energetic utilization (combustion). In the paper the experimental results are published. The briquettes quality evaluation was their aim. For the briquetting tests bark (pine), shavings (about 90% spruce + 10% pine), sawdust (spruce), birch chips and poplar chips were used. The basic physical-mechanical properties were the evaluation criteria. Following properties...