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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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The municipal waste collection yield assessment in the Czech Republic’s regions

100%
Altmann V., Neuberger P.
Infrastruktura i Ekologia Terenów Wiejskich
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2009
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nr 07
The objective of this paper is to zoom in on the system of separated waste collection in Czech Republic (CR). The system of packing waste collection is described. The analysis of collection of base commodities of communal waste (paper, plastics and glass) in chosen regions has been carried out. St edo eský region has been chosen because of the number of its inhabitants and as well because of its location in the middle part of CR and because it neighbours with the Czech capital city, Prague. Region Vyso ina shows average values in base commodities collection. The results of the chosen regions are being compared to the present status of separation of these wastes in CR which is counted by packing company EKO-KOM. The company caries out back withdrawal and usage of wastes of mentioned packages.
2
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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The optimisation of biomass combustion in small boilers

100%
Polak M., Neuberger P.
Infrastruktura i Ekologia Terenów Wiejskich
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2008
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nr 06
Biomass contains chemical energy which is a transformed Sun radiation. This energy can be used in many different ways. One of these is a direct combustion which is the most popular. The direct combustion of biomass is a technology which is well proven in large-scale heat and power generation. However, the situation in the small-scale heat generation is not so good. This paper describes results from the experimental combustion with various kinds of biomass in three different combustion devices. Saw dust is used in the experiment described below. The aim is to choose the best biofuel modification and the best way for its combustion from the point of view of power and emission parameters. As for the so far reached results of the experiment, the best in case of saw dust is the combustion with gasification of saw dust briquettes on stable grate without primary air or pellets in bottom supplied burner.
3

Biomass for heat production in rural areas

81%
Polak M., Neuberger P., Sleger V.
Electronic Journal of Polish Agricultural Universities. Series Agricultural Engineering
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2008
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tom 11
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nr 2
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Temperature changes in heat pump horizontal ground source

81%
Adamovsky R., Neuberger P., Sed'ova M.
Infrastruktura i Ekologia Terenów Wiejskich
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2009
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nr 07
The paper deals with assessment of thermal fields and temperature changes in ground massif with horizontal heat exchanger used as a heat source for a heat pump. Temperatures in the zone of the horizontal ground exchanger are compared with temperatures in a reference land. Changes of heat potential of the soil during the heating period are also assessed. Possibilities of recovery of thermal potential of the ground massif when utilizing vertical and horizontal exchangers are analyzed in the opening part of the paper. The results of the first verification indicated that average temperatures in the horizontal planes of the ground massif did not differ considerably with distance from the exchanger tube. Differences in average temperatures in reference and experimental lands confirmed sufficient heat potential of the ground massif even at the peak of the heating period. The differences in average temperatures reached up to 6.51 K in the end of the heating period while at the beginning of the heating period, the differences in average temperatures dropped to 1.35 K. The differences between maximum and minimum temperatures in the zone of the ground exchanger reached up to 1.9 K at the peak of the heating period and rose to 3.9 K at the beginning and end of the heating period. The first results of our measurements indicate the necessity of accumulation of thermal energy in the soil massif in the summer period like in case of the vertical exchangers.
5

Designing and operation of the evaporative system for air cooling in stables

81%
Neuberger P., Sleger V., Polak M.
Electronic Journal of Polish Agricultural Universities. Series Agricultural Engineering
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2008
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tom 11
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nr 2
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Analysis of leakage influence within capillary heat pipe recuperative heat exchanger

81%
Adamovsky D., Neuberger P., Adamovsky R.
Infrastruktura i Ekologia Terenów Wiejskich
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2007
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nr 3
The paper analyses the leakage of air-to-air recovery heat exchanger consisting of 100 capillary thermal tubes 1.5 m long and aligned in ten rows. The operation of the recovery exchanger prototype was tested in a pigsty. The analysis focuses on how the exchanger leakage affects the heat utilisation efficiency of the air ducted from the pigsty, changes in supply/exhaust air flow rate ratio, supply air temperature, thermal output obtained, and exchanger’s total thermal and mass balances. The results obtained in in-process measurements and the mass and thermal balances show that the exchange leakage causes the outside supply air to contain 12.1–37.3% of the pigsty exhaust air. The percentage of the pigsty air increases with the increase of mass flow rates of supply and exhaust air. This leakage resulted particularly in a major change in supply and exhaust air mass flow rates, higher moisture content, temperature and thermal flow of the air conducted in the pigsty. The change in air flow rates resulted in ventilation change so that the overpressure ventilation took place instead of balanced ventilation. This change led to increased thermal losses by air penetrating through leaks in the peripheral building structures. Increased supply air moisture content made it necessary to increase ventilation intensity in order to meet the required pigsty air parameters with respect of animal wellbeing and protection of peripheral building structures against dampness deterioration. The thermal flow increase of the air conducted in the pigsty due to the high enthalpy of the pigsty air mixed resulted in the higher secondary heat utilisation efficiency. The actual efficiency, however, was considerably lower. The differences of 2.7 – 14.5% between the exchanger’s measured and actual thermal efficiency according to relation (16) and those of 18.7 – 55.8% between the exchanger’s measured and actual running efficiency (13) increase as the ratio of supply and exhaust air mass flow rates increase.
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Modelowanie jednostkowego zużycia energii w cyklach technologicznych chowu trzody chlewnej

81%
Adamovsky R., Adamovsky D., Neuberger P.
Infrastruktura i Ekologia Terenów Wiejskich
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2006
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nr 2/2
Artykuł dotyczy określenia energochłonności czterech podstawowych grup w chowie trzody chlewnej. W wyniku pomiarów eksploatacyjnych oraz analiz teoretycznych uzyskano jednostkowe zużycie energii w odniesieniu do poszczególnych czynności wykonywanych w ramach produkcyjnego cyklu technologicznego. Opracowano proste zależności matematyczne, określające zależność jednostkowego zużycia energii od normatywnych bądź zalecanych wartości eksploatacyjnych dla danej grupy trzody chlewnej. Dokonano również oceny wzajemnych zależności jednostkowego zużycia energii w poszczególnych grupach zabiegów roboczych.
8
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Feasibility of using heat-recovery exchangers in livestock buildings at a site at a specific altitude with a specific average outdoor air temperature

81%
Sleger V., Neuberger P., Polak M.
Infrastruktura i Ekologia Terenów Wiejskich
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2009
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nr 07
The installation of an energy-saving facility must be preceded by analysis of its financial effectiveness. Among methods enabling such evaluation is the basic net profit calculation method. For this, the annual consumption of electricity for ventilation or of thermal energy for heating must be determined. The calculation formula uses the sum of energies for temperatures within the range from the calculation temperature for the area in question to the long-term average of the maximum temperature at the site, or to the temperature at which the heating power is zero. It is necessary to know the summary time of occurrence of a given temperature during a year. The site data can only be assessed based on long-term meteorological information. In fact, data used by current national standards to describe climatic conditions in the Czech Republic are from the years 1901 to 1950. The dependence of the average yearly temperature on altitude is shown in Fig. 1 for the 1961 1990 and 1991 2000 periods. It is evident that the average temperatures for the latter period are nearly 0.6 K higher than those for the former period, irrespective of the altitude. In this paper the climatic conditions are assessed based on daily data measured throughout the period from 1 January 1991 to 31 December 2000. Weather stations were selected so as to achieve a uniform coverage and continuity of measurement at each site (as far as possible). All the stations lie in the Czech Republic between 48.8° and 50.8° north latitude at altitudes from 158 m to 1324 m. It was the objective of this examination, based on the meteorological data collected to calculate the average number of days and hours during which the temperature during the year is lower than a specific limiting level, in dependence on the average yearly temperature of the site. Fig. 3 shows the average number of days in a year during which a temperature lower than a selected limiting level occurs, as calculated for the 1991 2000 period. The results are presented for 4 areas with average yearly temperatures of 6 °C 7 °C, 7 °C 8 °C, 8 °C 9 °C, and 9 °C 10 °C, respectively. The graphs enables us to ascertain the number of days during which a heating facility is in operation if the facility is activated by outdoor air temperature decrease to below a specific limiting level. If a typical daily temperature wave is considered, the method makes it possible to estimate the number of hours during which the air temperature is lower than the limiting level chosen. The difference between the data for various limiting levels allows us, for an area with a specific average yearly temperature to ascertain the time of occurrence of outdoor temperature within various ranges. The results of calculations are shown in Fig. 4 and Table 1. The method applied enables underlying data to be prepared for the assessment of energy demands for air heating at a given site and for estimation of the energy savings that could be achieved by installing economical air heating facilities in livestock buildings.
9
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Analyzing temperature changes in the ground massif with a horizontal heat exchanger in the course of the heating season

81%
Adamovsky R., Neuberger P., Sed'ova M.
Infrastruktura i Ekologia Terenów Wiejskich
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2010
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nr 11
The article is devoted to temperature changes in the ground massif with the horizontal heat exchanger as an energy source for a heat pump. The article was aimed at analyzing temperature changes in the ground massif with the horizontal heat exchanger at the beginning, in the course of and at the end of the heating season. Another aim was to analyze temperature differences in the area of the horizontal exchanger and the reference lot. The heat flow utilized in the evaporator of heat pump was extracted from the ground exchanger (nominal output at the condenser was 10.5 kW). Temperatures of the ground massif with the horizontal heat exchanger were measured in its plane in depths of 0.75 m, 0.5 m and 0.25 m. The temperature inside the ground massif on the reference lot and ambient parameters were measured as well. It is obvious that the difference of energetic potentials inside the ground massif with the heat exchanger and on the reference lot is insignificant at the beginning of the heating season. During the heating season, the difference of ground massif energetic potentials increases; at the end it is constant. The difference of temperatures in horizontal planes was not significant at the beginning of the heating season; however, it gradually increased. Maximum differences were detected in the area of the heat exchanger. In higher strata, the difference between temperatures decreases. During a major part of the heating season, temperatures at pipes of the ground exchanger were negative. This fact affected amounts of heat extracted from the ground massif.
10
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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The practical experience with adiabatic cooling withfogging systems in the houses for pig breeding

81%
Neuberger P., Sleger V., Polak M.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2002
|
tom 486
|
nr 1
Heat stress of domestic animals has the increasing influence on the farming economy in Central Europe. It is not caused only by global warming. Substantial share in this situation has the introduction of new races of animals of higher productivity. On the other hand, breeding of the highly productive animals has a negative influence on moisture and heat increase. These problems can be solved by using direct adiabatic cooling system which is used especially in poultry production nowadays. An effort was made to use this technology for pig breeds too. The paper summarises the results from the observation focused on the comparison of cooled and non-cooled stable for pig breeding. The installation of this cooling system is one of the first example in pig houses in the Czech Republic. The decrease of air temperature by about 2.5-3 K was reached by means of evaporative cooling. However, it should be said, that the system was not adjusted to optimal parameters during the experiment, yet. We can expect the temperature decrease of about 5.5-6 K after the optimal adjustment.
11
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Verification of the effects of the secondary heat recovery from ventilation air in an animal house for the fattening of broiler chickens

81%
Adamovsky R., Adamovsky D., Kara J., Neuberger P.
Infrastruktura i Ekologia Terenów Wiejskich
|
2008
|
nr 06
This paper presents results of the verification of a heat exchanger composed of gravitation thermal pipes installed in a broiler chicken feeding facility. The objective of the study was to verify the possibility of the application of a power management system including a heat recovery system in a heavy-duty environment of a broiler chicken fattening facility and to specify effects of the system upon the specific consumption of energy for space heating and ventilation of the animal house. The calculation of the thermal balance of the animal house documents that the power management system that includes a heat recovery exchanger unit may reduce the thermal capacity of external sources of heat in the animal house by 26.5% even when subject to extreme conditions and at the atmospheric temperature of -12°C and the age of chickens being 1 day. The results of the metering and calculations of the efficiency have proven that the heat exchanger reaches the operational efficiency of 10–47% and thermal efficiency of 20–80% even during the most demanding operational first twenty days of the breeding cycle of broiler chickens. The specific consumption of energy for space heating and ventilation related to 1 kg of the live weight of chicken in the animal house facility A provided with a heat recovery exchanger unit at the average atmospheric temperature during the cycle being 4.3°C amounted to 278.5 Wh. In the animal house B as not provided with the heat recovery exchanger units hosting the same number of chickens and provided with the same process and thermal loss due heat transmission through peripheral structures being one half compared to the animal house A, the specific consumption of energy per 1 kg of the live weight of chicken was 420.5 Wh.
12

Experimental verifying of mathematic model for biomass combustion

81%
Polak M., Neuberger P., Soucek J.
Annals of Warsaw University of Life Sciences - SGGW. Agriculture
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2008
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nr 52 Agric.Forest Eng.
89-93
13
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Energy sorrel - an alternative fuel for rural areas

81%
Polak M., Neuberger P., Sleger V.
Infrastruktura i Ekologia Terenów Wiejskich
|
2007
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nr 3
The research is focused on energy sorrel as a fuel for local low-power heating systems with output up to 100 kW. Sorrel is perennial plant surviving in its location nearly 18 years which is very good from the point of crop expenses. It is a robust plant with height of about 2 m in second year of plantation. Dry phytomass is energetically rich fuel with total heating value 17.5 – 18.0 MJ.kg-1 at the average yield of 10 tons per hectare. An experimental combustion of pure sorrel and its blends were done with boiler VERNER A25 – a hot water boiler for pellets. 11 different sorrel fuels consisting of 5 primary kinds were tested during the experiment: sorrel (Rumex tianshanicus x Rumex patientia), Phalaroides arundinacea, Canabis sativa, pine-bark, sorrel (Rumex tianshanicus x Rumex patientia), brown coal. Based on collected data it is possible to obtain an overview of these fuels and their emission properties. Satisfactory values of CO concentration are possible to gain partly by choosing appropriate combustion device and its settings and partly by mixing with other types of fuel. In the case of sorrel the combination of both has been shown very useful. It is very hard to combust sorrel only, and its testing proves unsatisfactory results. But if we combust blend of sorrel and canary grass 1:1 in the same device, the results are somewhat better. The best results can be reached if we burn this blend in more suitable device. By this way it is even possible to fulfil the emission limits. However, if we burn only pure sorrel in another burner, the emissions are very dissatisfactory again. Another possibility of how to burn sorrel effectively is to combine it with brow coal. On the basis of received results, fuel containing 10 to 20 % of coal can be recommended. From point of view of ash properties pure sorrel appears a problematic fuel. During our experiment ash accumulation in combustion chamber was observed. Unburnt fuel blocked air intakes which caused burning deterioration and increase of CO emissions. All above mentioned facts indicate that sorrel burning is possible if we fulfil all demands required for this fuel. Combustion of pure sorrel in any device without special settings means in many cases non effective use of fuel and bad emissions.
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