36 research outputs found

    On the possibility of cleaning producer gas laden with large quantities of tars through using a simple fixed-bed activated carbon adsorption process

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    The study presents the results of research on using fixed-bed, activated carbon (AC) adsorbers in the cleaning of heavily tar-laden producer gas from the gasification of biomass. The efficiency of removal of organic compounds as well as the remaining adsorption capacity of the bed were determined using a spectrum of commonly applied diagnostic methods, including qualitative and quantitative analyses of the adsorbed compounds and changes in the pore volume of the bed material (IN, MN). The authors compare these lab quantifications with a simple technique which is based on the analysis of the changes in the position of temperature front in the bed. The main benefit of the latter is the possibility of performing the diagnostics of the bed "online" and using low-cost temperature measurements. The test was performed using a commercially available AC Desotec AIRPEL 10-3 and real producer gas obtained through the gasification of alder chips. For tar, VOC and C-2-C-5 compounds, the removal efficiencies reached respectively 74.5%-wt., 52.8%-wt., and 85.5%-wt. Obtained results indicate that depending on the final application of the gas, the use of dry adsorption systems is an interesting alternative to the well-established but complicated, cumbersome, and costly wet scrubbers. Moreover, a concept for in situ regeneration of the adsorbent, coupled with direct reforming of the tars, is presented and discussed.Web of Science1519art. no. 743

    The Arf-GEF GBF1 undergoes multi-domain structural shifts to activate Arf at the Golgi

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    Golgi homeostasis require the activation of Arf GTPases by the guanine-nucleotide exchange factor requires GBF1, whose recruitment to the Golgi represents a rate limiting step in the process. GBF1 contains a conserved, catalytic, Sec7 domain (Sec7d) and five additional (DCB, HUS, HDS1-3) domains. Herein, we identify the HDS3 domain as essential for GBF1 membrane association in mammalian cells and document the critical role of HDS3 during the development of Drosophila melanogaster. We show that upon binding to Golgi membranes, GBF1 undergoes conformational changes in regions bracketing the catalytic Sec7d. We illuminate GBF1 interdomain arrangements by negative staining electron microscopy of full-length human GBF1 to show that GBF1 forms an anti-parallel dimer held together by the paired central DCB-HUS core, with two sets of HDS1-3 arms extending outward in opposite directions. The catalytic Sec7d protrudes from the central core as a largely independent domain, but is closely opposed to a previously unassigned α-helix from the HDS1 domain. Based on our data, we propose models of GBF1 engagement on the membrane to provide a paradigm for understanding GBF1-mediated Arf activation required for cellular and organismal function

    Application of a Thermal Performance-Based Model to Prediction Energy Consumption for Heating of Single-Family Residential Buildings

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    Energy consumption for heating of single-family residential buildings is a basic item in energy balance and significantly affects their operating costs. Accuracy of heat consumption assessment in existing buildings to a large extent determines the decision on taking actions aimed at heat consumption rationalization, both at the level of a single building and at regional or national level. In the case of energy calculations for the existing buildings, a problem often arises in the form of lack of complete architectural and construction documentation of the analyzed objects. Therefore, there is a need to search for methods that will be suitable for rapid energy analysis in existing buildings. These methods should give satisfactory results in predicting energy consumption when there is limited access to data characterizing the building. Therefore, the aim of this study was to check the usefulness of a model based on thermal characteristics for estimating energy consumption for heating in single-family residential buildings. The research was conducted on a group of 84 buildings, for which the energy characteristics were determined based on the actual energy consumption. In addition, information was collected on variables describing these buildings in terms of construction technology and building geometry, from which the following were extracted for further calculations: cubic capacity, heated area, and year of construction. This made it possible to build a prediction model, which enables the application of a fast, relatively simple procedure of estimating the final energy demand index for heating buildings. The resulting calculations were compared with actual values (calculated from energy bills) and then evaluated according to the standards for evaluating model quality proposed by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). In this way, it was possible to determine whether, in the absence of building documents, the indicative method gives good results when estimating the energy demand for heating single-family residential buildings

    Assessment of the correctness of power of radiators in systems with gas heat sources in residential buildings

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    W pracy opisano badania wykonane na grupie 57 budynków jednorodzinnych, w których dokonano konwersji źródła cie-pła na gazowe wraz z wymianą grzejników. Badania miały na celu sprawdzenie dostosowania mocy zainstalowanych grzejników do potrzeb cieplnych obiektów. W celu określenia popytu na ciepło dla każdego z budynków wykonano obliczenia zapotrzebowania na moc do ogrzewania, obliczono moc grzejników w zależności od rodzaju zastosowanego kotła gazowego (zwykły lub kondensacyjny), a następnie porównano z mocą grzejników, które były zainstalowane w poszczególnych budynkach. Pozwoliło to na ocenę poprawności doboru mocy grzejników w zależności od temperatur zasilania grzejników w poszczególnych instalacjach. Na podstawie przeprowadzonych obliczeń stwierdzono, że grzejniki były stosunkowo dobrze dobrane w budynkach z instalacjami, gdzie źródłem ciepła były kotły gazowe zwykłe (z zamkniętą lub otwartą komorą spalania), natomiast w przypadku budynków, w których zainstalowano kotły gazowe kondensacyjne, sto-pień dopasowania wynosił 0,6, a zatem grzejniki były niedowymiarowane, tzn. że powierzchnia oddawania ciepła jest zbyt mała i niedostosowana do potrzeb cieplnych budynków oraz parametrów pracy instalacji grzewczej.The study describes tests carried out on a group of 57 single-family residential buildings in which the heat source was converted into gas with the replacement of radiators. The tests were aimed at checking the adaptation of the installed heaters' capacity to the needs of thermal of buildings. In order to determine the demand for heat, for each building calcu-lations were made for the demand for heating power, the power of the heaters was calculated depending on the type of gas boiler used (ordinary or condensing) and then compared with the power of radiators that are installed in individual buildings. This allowed to assess the correctness of the power selection of radiators depending on the supply temperatures of radiators in individual installations. Based on the calculations performed, it was found that radiators are relatively well selected in buildings with installations where the heat source is ordinary gas boilers (with closed or open combus-tion chamber), while for buildings in which gas condensing boilers are installed, the degree of fit is 0.6 and thus the radi-ators are too small - the heat dissipation surface is not adapted to the thermal needs of buildings and the parameters of the heating installation

    Analysis of heat source selection for residential buildings in rural areas

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    The research aiming to check whether the output of currently installed boilers matches the use requirements together with estimation of their energy efficiency was carried out on a group of 84 single-family residential buildings located in rural areas. Heating and hot water energy needs were calculated for each building in order to determine the use requirements. This enabled verification whether the currently installed boilers match the actual use requirements in the buildings. Based on the calculations it was determined that the designed average boiler output in the group of buildings subject to analysis is 15.7 kW, whereas the mean rated output capacity of boilers installed therein is 25.4 kW. On average, the output capacity of the installed boilers exceeds the use requirements for the buildings by 60%. To calculate the energy efficiency of boilers, the mean annual boiler output capacity use coefficient was determined. For boilers selected on the basis of standard calculations, the mean coefficient is 0.47. For boilers currently in use it is 0.31, less than the above figure. The above calculations show that if boilers were correctly selected in compliance to the building needs, then the average estimated seasonal efficiency of 65% would be feasible. However, in the current state the achievable efficiency is approx. 55%

    Evaluation of differentiation of local sources of biomass in the to cover the needs of heating in rural areas of the swietokrzyskie province

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    Przeprowadzono analizę zużycia ciepła i potencjału energetycznego biomasy w poszczególnych powiatach województwa świętokrzyskiego. Popyt na ciepło na obszarach wiejskich województwa kształtuje się na poziomie ok. 20 PJ, zaś potencjał techniczny biomasy, która może być wykorzystana na cele energetyczne wynosi 5,2 PJ. Na tej podstawie szacuje się, że udział biomasy w pokryciu potrzeb cieplnych na terenie województwa może wynieść 33%. Najwyższy udział biomasy w zaspokojeniu potrzeb cieplnych występuje w powiatach kazimierskim i włoszczowskim, najniższy zaś w powiatach sandomierskim i kieleckim.The analysis of heat consumption and energy potential of biomass in particular poviats of the Świętokrzyskie Province was carried out. The demand for heat in the rural areas of the voivodship is around 20 PJ, while the biomass technical potential that can be used for energy purposes is 5.2 PJ. On this basis, it is estimated that the share of biomass in the cove-rage of thermal needs in the province may amount to 25%. The highest share of biomass in satisfying thermal needs occurs in the districts of Kazimierza and Włoszczowa, and the lowest in the districts of Sandomierz and Kielce

    Comparison of the power of existing boilers with respect to the need for heating of residental buildings in rural areas

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    W pracy opisano badania wykonane na grupie 84 budynków mieszkalnych jednorodzinnych, zlokalizowanych na obszarach wiejskich, które miały na celu sprawdzenie dostosowania mocy zainstalowanych kotłów do potrzeb cieplnych obiektów. W celu określenia popytu na ciepło dla każdego z budynków wykonano obliczenia zapotrzebowania na moc do ogrzewania i przy- gotowania ciepłej wody użytkowej. Pozwoliło to na sprawdzenie dostosowania mocy kotłów do rzeczywistych potrzeb cieplnych w budynkach. Na podstawie przeprowadzonych obliczeñ stwierdzono, że wartość przeciętna obliczonej mocy kotła w analizowanej grupie budynków wynosi 15,7 kW, natomiast średnia moc znamionowa kotłów w nich zainstalowanych wynosi 25,4 kW. Moc zainstalowanych kotłów w budynkach jest średnio o 60% większa niż to wynika z ich popytu na ciepło.The study presents research conducted on a group of 84 detached houses located in rural areas which were aimed at checking the adaptation of the power of installed boilers to the actual heat demand. In order to determine the heat demand calculations for each building were made for the power demand for heating and domestic hot water preparation. It allowed to check the adaptation of the installed boilers' capacity to the actual needs in the buildings. Basing on the calculations carried out, it was found that the average value of the calculated boiler power in the analyzed group of buildings amounts 15.7 kW, while the average rated power of the boilers installed in them amounts 25.4 kW. On average, the installed boiler capacity is 60% higher than the thermal needs of the facilities

    Neural Methods Comparison for Prediction of Heating Energy Based on Few Hundreds Enhanced Buildings in Four Season’s Climate

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    Sustainable development and the increasing demand for equitable energy use as well as the reduction of waste of energy are the author’s social and scientific motivations. This new paradigm is the selection of a pertinent methodology to evaluate the efficiency of habitat thermomodernization, which is one of the scientific tasks of the presented study. In order to meet the social and scientific requirements, 380 buildings from the end of the last century (made of large plate technology), which were thermally improved at the beginning of the XXI century, were designed for a comparative analysis of the predictive modelling of heating energy consumption. A specific set of important variables characterizing the examined buildings has been identified. Groups of variables were used to estimate the energy consumption in such a way as to achieve a compromise between the difficulty of obtaining them and the quality of forecast. To predict energy consumption, the six most appropriate neural methods were used: artificial neural networks (ANN), general regression trees (CART), exhaustive regression trees (CHAID), support regression trees (SRT), support vectors (SV), and method multivariant adaptive regression splines (MARS). The quality assessment of the developed models used the mean absolute percentage error (MAPE) also known as mean absolute percentage deviation (MAPD), as well as mean bias error (MBE), coefficient of variance of the root mean square error (CV RMSE) and coefficient of determination (R2), which are accepted as statistical calibration standards by (American Society of Heating, Refrigerating and Air-Conditioning Engineers) ASHRAE. On this basis, the most effective method has been chosen, which gives the best results and therefore allows to forecast with great precision the energy consumption (after thermal improvement) for this type of residential building

    Productivity frameworks in big data image processing computations - Creating photographic mosaics with Hadoop and Scalding

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    AbstractIn the last decade, Hadoop has become a de-facto standard framework for big data processing in the industry. Although Hadoop today is primarily applied to textual data, it can be also used to process binary data including images. A number of frameworks have been developed to increase productivity of developing Hadoop based solutions. This paper demonstrates how such a framework (Scalding) can be used to create a concise and efficient solution to a big data image-processing problem of creating photographic mosaics and compares it to a Hadoop API based implementation

    Selection of a Multicriteria Method for Selecting Independent Variables for Forecasting the Energy Potential of Municipal Waste—A Case Study in Poland

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    The study examined the usefulness of selected classification methods and independent variable selection (conditional attributes) for building a model based on rough set theory (RST). The aim of the study was to estimate the local indicator of municipal waste generation and the energy potential of the waste, which could be utilized in thermal waste treatment facilities. The research was conducted on a group of 2451 municipalities in Poland which differed from each other in terms of administrative type (urban, urban–rural, and rural municipalities). These municipalities were described using 4 qualitative variables and 27 quantitative variables available in statistical reports. Using five submethods of variable classification, sets of features characterizing them in terms of the amount of municipal waste produced were extracted from the collected data. Purposeful selection of conditional attributes for modeling the unitary municipal waste accumulation index allows for reducing the number of decision variables without compromising the quality of the model. During the analysis, the number of conditional attributes was reduced from 31 to 3 for urban municipalities, 5 for urban–rural municipalities, and 7 for rural municipalities. The analysis results showed that the developed models exhibited mean absolute error (MAE) values ranging from 30 kg·(per·year)−1 to 52 kg·(per·year)−1, while the mean absolute percentage error (MAPE) ranged from 9% to 21%. By utilizing municipal waste for energy purposes, an average of approximately 160 kWh·(per·year)−1 for rural municipalities and around 270 kWh·(per·year)−1 for urban municipalities can be obtained
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