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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.

This article presents the main problems associated with cereal harvesting in sloping areas. The presented innovative aerodynamic system supporting the separating unit of combine harvester can be one of the ways to counteract the negative effects of harvesting machines work on slopes. The Monte Carlo numerical method, presented in this article, was applied in the optimization of an aerodynamic sieve separation process on an inclined terrain. The given variables are the transverse slope of separator α (of the sieve), longitudinal slope β and the output of the main and side fans. The Monte Carlo method makes it possible to determine an optimized set of parameters (α = 10°, β = 2.8°, δ = 9°), the output of the main fan (0.67 m3 s−1) and the output of the side fan (1.86 m3 s−1), allowing to obtain the best indicator values of 2.1% grain loss and 97.5% grain purity.

Increasing global population growth has a significant impact on waste production. The European Union (EU) focuses on waste recycling, biological treatment, and reuse. In the case of biodegradable waste, a significant problem is the long process of material decomposition so that the product meets the requirements of national regulations and EU directives. The search for a way to accelerate this process is still ongoing. This study presents the composting process of green waste under hyperbaric conditions. Eight experiments, four with air exchange frequency tAE = 4 h and four experiments with tAE = 8 h were established. The experiments were conducted in four variants: 0 (atmospheric pressure) and overpressures 50, 100, and 200 kPa. They were carried out on the same input material characterized by the initial moisture content of 60% and a mass of 2000 g. During the composting of green waste, all parameters of the obtained product (moisture content, pH, loss on ignition (LOI), C:N ratio, nutrient content (P, K), and the respiratory activity of microorganisms (AT4)) were also evaluated. The most significant weight loss of the composted material was observed in the variant of an overpressure of 200 kPa (tAE = 4 h). The compost weight in relation to the original material decreased by 23.7%. The highest organic matter removal efficiency was obtained for the overpressure variants of 50 and 100 kPa (tAE = 4 h).

The paper presents a recommendation on how to use waste heat of post-treatment water in the balneological institute in Lądek Zdrój health resort. This heat may be used in stenothermal fish big scale breeding. The presented innovative solution of a technological breeding line of African sharptooth catfish (Clarias gariepinus) has not been carried out in practice yet and except for ecological values, it may soon bring real profits. The presented calculations show that the analysed technology may bring a real return of the incurred investment expenditures after approx. 6.5 years from the moment the production was launched. The calculated internal return rate is 14.25% and considerably exceeds the border rate (4%). As it was shown, there is an additional possibility of improvement of this profitability through the use of funding as a part of the Operational Programme Fisheries and Sea 2014-2020. Then, at the funding of investment in the amount of 50% of qualified costs IRR will increase to 25.03%. The period of capital return will decrease to approximately 3.5 years.

The article presents the possibility of using artificial neural networks to model the operating parameters of a counter-rotation mini wind turbine. The work is based on data from wind turbine research results conducted in an aerodynamic tunnel in the Institute of Agricultural Engineering at the University of Environmental and Life Sciences in Wroclaw. The correlation between the depended variable (generated power P) and independent variables (average velocity of the air stream v, wedge angle of the first rotor blades, wedge angle of the second rotor blades, distance between rotors) was examined. The quality of the network was verified based on the mean-square error. The construction of the turbine allows to steplessly change of the blades wedge angle and the distance between rotors. Hence in the future the constructed network model can be used for programming the controller allowing to optimize the operating parameters of the wind turbine to maximize the generated power.

The paper presents analysis of the impact of irrigation dose on the winter wheat Bystra yield, which is recommended for cultivation in Poland. It is a low-growing high-yield wheat cultivar. A reel sprinkler equipped with a computer for control of parameters of its operation, which was supplied with pond water was used for irrigation. Test were carried out on five fields, where four irrigation doses were used: 15, 20, 25, 30 mm. A change of weather during research in May and June caused the need to irrigate a field four times. During research, the size of the irrigation dose was measured with rain gauges on each of the investigated fields in five measurement points. One of the fields was a control field, which was not irrigated. The investigated wheat was characterized during harvesting. Research proved that the size of the irrigation dose influences the wheat yield. The grain yield between a control field and a field with the highest irrigation dose increased by twofold. Moreover, analysis of costs incurred during sprinkling were analysed.

The paper evaluates operation of the separation unit of NH CR9080 combine harvester. A considerable technical and technological progress has taken place in presently used harvesters. Among others, efficiency increased and equipment has been enhanced with elements which improve the operation quality. The objective of the paper was to determine the quality of the separating unit of a combine harvester New Holland CR9080. During the research, losses on screens and rotor, cutting height of rapeseed, mowing speed, rotation of fans, rotors and engine were determined. Relation of losses on screens to combine operation parameters was determined with a model of multiple regressions. The rotational speed of rotors, mowing speed and rotational speed of the combine engine have a significant effect on losses on screens at the rapeseed harvesting with the investigated combine.

In order to support the designing process and selection of subassemblies of an installation, specialist application programs are created. Selected applications were compared in the paper through their use for designing hypothetical solar collector systems for a single family house with a varied number of household members. With the use of particular applications, calculations for the same input assumptions were made. Results obtained with the use of a traditional calculation method were a reference point. Applications were compared on account of the type and amount of input parameters which may be introduced, type and number of determined values and their value. Based on the obtained results usefulness and scope of use of an application were assessed.

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.

In some opinion-forming environments the problem of noise emitted by wind power stations is very controversial. It is even suggested that they negatively affect the quality and length of human life. Based on the review of domestic and foreign publications an analysis of the impact of the low-frequency noise on a human being was carried out. Wind power stations operating in groups (farms) constituted the source of noise. It was proved that the level of acoustic pressure with G weighting does not exceed the value of 85 dB. The value of the admissible burdensome noise (102 dB) was exceeded in the bus cabins which were driving with the speed exceeding 30 km·h−1. The opinion of the Ministry of Health confirms the findings. It proves that the present knowledge does not allow a clear indication of the relation between the wind farms and their negative impact on the human health.

This paper reports the results of measurements and calculations of heat production from geothermal waters in a Polish geothermal plant in Banska in the years 2010–2013. Statistical analysis was used to create a regression model and an artificial neural network model. The models allow us to predict the volume of heat produced, depending on outside air temperature. In addition, the study indicates that geothermal energy is one of the most predictable sources of renewable energy, which is important from the point of view of reliability of exploitation. Production of energy from renewable sources, which include geothermal energy, fits the current trends in the energy policy of the Polish state.

In the article we undertook the attempt of using the theory of random fields in the analysis of the separation process of particles in non-contiguous systems. The presentation of the complete model is a complicated problem. We can say that this article is start point of the theory, which will be supplemented gradually in the future. The separation process of particles on sieves is a phenomenon with random character. It is a result of random character of cleaned mixture and the nature of the separation process. Undoubtedly, an important part is played by the theory of random fields in which system-events, inherently not determined, are described in undetermined-probabilistic way. However, we can perceive one paradox in such actions – correctly constructed probabilistic models serve to impose deterministic frames on the given random process. We can say that stochastic models generate the matrix of the causal-consecutive dependence, which will give the ability of controlling a given process.