The paper deals with comprehensive quality and physical parameters of commercial cokes. It aims to present comparative analysis of acquired values with standards found in other literature sources. There were analysed 15 samples of coke from current industrial operation. There were carried out chemical analysis, CSR and CRI characterization. Density, porosity, compressive strength, friction coefficient, volume of particles were determined. There was performed one-way analysis of variance (ANOVA) by Statistica v.12.0 (StatSoft, Inc., Tulsa, USA) to determine significant correlation between the measured parameters. The highest correlation coefficents were noted between the pycnometer density of cokes and CSR index (r = 0.925) and CRI index (r = −0.828). The comparative analysis of quality and physical parameters with values mentioned in literature revealed the significant differences in the values of apparent density, bulk density and true density of pulverized samples.

The article presents the results of wind-tunnel tests and field studies of a mini dual-rotor wind turbine. The first stage involved testing of an open-circuit wind tunnel built with the aim of performing laboratory tests. The coefficient of uneven air stream disRomAński L, Bieniek J, komARnicki P, DęBowski m, DeTynA J. operational tests of a dual-rotor mini wind turbine. eksploatacja i niezawodnosc -maintenance and Reliability 2016; 18 (2): 201-209, http://dx

The calculation method commonly used in the industry takes into consideration mainly fuel consumption (excluding electricity) and the amount of removed moisture which is reflected in the unit MJ·(Mg·%)−1. This is not a scientific approach because the result will change if the basic moisture is different (drying from 21% to 18% will consume less energy than drying from 18% to 15%). This paper aims to compare the energy consumption of two industrial continuous flow grain dryers powered by LPG and hard coal based on a comprehensive approach to energy efficiency calculation enriched with electricity consumption, flow measurements, and control of grain moisture. It could be useful for manufacturers who could use this method to generate more reliable data in their product datasheets, and it could also be legally regulated as an appropriate tool for calculating the energy consumption of agricultural grain dryers. According to the approach presented in this paper, the S428.CS construction powered by LPG gas had an energy consumption that was 6.14% lower than the DT2532 dryer construction, which used hard coal.

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The article presents an exploitation assessment of New Holland CX780 combine operation. Significant technical and technological progress is visible in modern harvesters. Inter alia, performance increased and elements improving the quality of work of harvesters appeared. The objective of the paper was to determine efficiency of the New Holland CX780 harvester operation including factors which affect its operation. Time structures of particular activities of combine operation and ratios of these times use were determined during tests. Yield value and moisture of collected seeds was determined. Studies proved that effective time of combine operation in the process of rapeseed and wheat grain harvesting was less than 50% and was caused by long preparation of a machine for operation. Preparation for operation of a combine influences its performance in the total time. It was 22% of the total operation time in case of wheat harvesting and 20% in case of rapeseed harvesting.