Search

Published After
Published Before

Search Results

  • Basic Research for the Development of Fertiliser Spreaders
    52-57
    Views:
    118

    The knowledge of the physical characteristics of fertiliser particles is essential for the constructors and operators of fertiliser distributors. Among physical characteristics, the most important are the frictional and aerodynamic properties for the description of particle movement. Adjustable angled slopes, shearing boxes and various rotating disks are used to identify frictional properties. We have developed a high precision shearing box with digital force measuring cells and a distance signaller (incremental transducer) that we use for slide tests efficiently. We measured the frictional characteristics of 6 different fertilisers: the inner coefficient of friction and the coefficient of friction on ten test surfaces most commonly used in machinery, and we specified the relationship between displacement, loading and the coefficient of friction. We can conclude that the material of the frictional surface significantly influences the force of friction.
    However, our experience tells us that the shearing box is not suitable for the measurement of the inner friction, since the examined particles slide on the metal surface of the shearing box in a growing extent in the course of displacement, so it does not measure the real inner friction. Therefore, in our experiment we have developed rotating shearing equipment with a constant shearing surface to identify the inner friction. We tested the equipment with fertilisers and we identified the inner frictional characteristics of 6 different fertilisers. With the developed rotating shearing apparatus we could measure the real inner friction of the particles.
    To identify the aerodynamic characteristics of granules, wind tunnels and free-fall tests are used. An elutriator have been developed for our investigation. We have used fertilisers for testing the measuring equipment and we have identified the aerodynamic characteristics of 6 different fertilisers.

  • Examination of different grain hardness varieties of the grinding technology properties of wheat
    423-435
    Views:
    206

    In the mill industry, the purpose of the grinding technology is to separate wheat endospermium and shell and to recover grists. The most important and the highest energy requirement operation is shredding. Flour quantity and quality produced from wheat depends on the variety of wheat that will be shredded, the type of grinding equipment and the condition used before the grinding. For this reason, during my experiments, I ground two grain structured varieties of wheat in laboratory conditions using a disk grinder, stone grinder and roll grinder in air-dry and conditioned states. We measured the equipment’s performance and the produced grist’s particle size distribution, followed by the calculation of the energy requirements of the grinders. In the grinding experiments we compared the ash contents of the different particle sized grist’s fractions to map the wheat’s particular properties.

  • The applied mechanical equipments for wastewater treatment in the észak-Alföld region
    171-178
    Views:
    169

    In this study we presented the results of a survey research, which was performed during 2015 at 34 sewage treatment works, operating in Észak-alföld region (Hungary). The survey focused on applied mechanical equipment and works of art of the sewage treatment establishments.

    The results of the survey showed that the majority of the examined sites (approx 65%) are working with capacity utilization of 50–100%,merely the 12% of plants was overload. It was found analyzing of specific energy consumption of the sites that the largest value (1.1 kWh per m3) was at the plants with smaller capacity (0–1000 m3 per day). It was clear during the questionnaire processing of the survey that almost all of the works applied activated sludge for sewage treatment The sludge treatment of the sewage plants is conducted by two methods; aerobic- and mixed (anaerobic and aerobic) sludge stabilization. We suggest for the plants with small capacity to use deep aerators, since anachronistic method used the at 3% of the settlements.

  • The effect of hybrid, nutrient-supply and irrigation on the grain moisture content at harvest and the starch-content of maize (Zea mays L.)
    89-95
    Views:
    122

    Maize is a worldwide dominant plant. According to nowadays plant production principles it is important to investigate and optimize the site-specific nutrient-supply and other production factors, such as hybrid and irrigation, in the case of this plant as well.
    At the Research Institute of the University of Debrecen, Center of Agricultural Sciences and Engineering, at Látókép the effect of nutrient-supply and irrigation on the quantity and quality parameters of different hybrids were investigated in a small plot long-term field experiment. In this paper we introduce the results regarding the corn moisture-content and the starch content of the yield.
    We have chosen three maize hybrids – that have been bread in Martonvásár – for our investigations. The effect of macronutrients is investigated in this experiment on five levels. The half of the experimental area can be irrigated during the vegetation period – whenever it is needed – by linear irrigation equipment, but on the other half only the water amount originating from the precipitation can be used by plants.
    In the year 2008 the hybrid affected the grain moisture content at P=0.1% level, while nutrient-supply had an effect at P=10% significance level. We haven’t revealed either any effect of irrigation or of interrelationship between production factors. It can be stated that there are differences between the hybrids on each nutrient-supply and on both irrigation levels. The grain moisture content increased parallel to the longer vegetation
    periods.
    The starch content of maize is mostly affected by the hybrid,
    so on P=0.1% significance level. Regarding our results, it can be
    stated, that the starch content shows a decreasing tendency
    parallel to the longer vegetation periods.