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Bayesian network development for depots location selection with biomass supply system excellenceAbulhamail, Alaa Ashraf 09 August 2022 (has links) (PDF)
The renewable energy of the wood pellet market has taken great attention over the last few periods. However, the returns from the pellet business depend largely on how well the quality of biomass. The objective is to economically harvest pellets matching pellet standards set forward by the U.S. markets. The single-mindedness of this study is to develop a Bayesian network model to ensure a high-quality flow through the supply chain of the pallet industry in the top ten counties in Mississippi state. Multiple critical decisions (harvesting, storage, transportation, and quality control) of a biomass-to-pellet supply system could potentially affect the supply chain. The biomass-to pellet supply chain is an extremely challenging problem. For Multi-criteria Decision Making,we have developed criteria and sub-criteria associated with biomass-to pellet supply chain pellet. Experimental results specify that the biomass-to-pellet stream system is complex to the biomass quality parameters especially ash and moisture contents. Fifty were studied and ten locations were recommended and ranked based on affordability and resiliency of the availability of both corn stover and forest residues in the depot facilities. There are several anticipated and unpredicted energy turbulence in the Depots property. Pellets have been recognized as an alternative power approach to managing risk throughout power generation. These prospective users from using alternative power. This research proposes a solid foundation for in-depth future research to acquire detailed insights into how the Pellets depots location works in practice in Mississippi state to give a more substantial basis for strategic, tactical, and operational levels of possible risk profiles in Mississippi state.
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Estimação do teor de cinzas da camada I do carvão do leão através da reflectância utilizando a teoria Kubelka-MunkJesus, Leandro Gustavo Mendes de January 2014 (has links)
O principal parâmetro de avaliação da qualidade de carvões para uso na geração de energia termoelétrica é o percentual de cinzas. Em uma planta de beneficiamento, saber o percentual de cinzas da alimentação, concentrado e rejeito é de suma importância para os ajustes nos equipamentos de concentração. No caso do carvão da camada I1 do depósito mineral do Leão a janela de tempo entre o ponto mais adequado para amostragem e o fim da campanha de beneficiamento não propicia que se conheça o teor de cinzas da alimentação do processo de beneficiamento. Em virtude disso, este trabalho tem como objetivo de fornecer uma estimativa confiável do teor de cinzas da alimentação para propiciar a aplicação na planta de beneficiamento. Para esse intento utilizou-se a teoria de Kubelka-Munk que por meio de sua expressão matemática transforma a reflectância em uma grandeza aditiva que propicia a estimativa das porcentagens de matéria orgânica e mineral contida no carvão devido a diferença de reflectância entre esses materiais. Como resultado final foram gerados diversos modelos com intuito de verificar qual deles se adaptava melhor aos dados. Por fim, foi possível concluir que há possibilidade de estimar o teor de cinzas de carvão por meio da reflectância e com confiabilidade de 96,78% que toda a leitura agrega um erro máximo de ± 5% para o melhor modelo. / The main parameter in quality evaluation of coals employed in power generation is the ash content. In a beneficiation plant, knowing the ash content of the feed, concentrate an tailings is mandatory to set up the concentration equipment. In the case of the I1 coal seam of Leão’s deposit the time window between sampling routine and beneficiation routine does not allow to know the feed ash content before the beneficiation process. By this reason, this work aims to provide a reliable estimative of the feed ash content to propitiate its application in the beneficiation plant. For this purpose it was used Kubelka-Munk’s theory that, by using a mathematic expression, transforms reflectance into a additive quantity which allows to estimate mineral and organic matter present in coal by the difference of reflectance between these materials. As result, it was generated several models in order to analyze which one is better suited to the data. Finally, as a conclusion, it is possible to infer the ash content of coal by reflectance with confidence of 96,78% that all measure brings up a maximum error of ± 5% for the best model.
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Removal of Ash from Waste-Tire Pyrolytic Char by the Principle of Electrostatic SeparationLin, Chih-Feng 06 July 2008 (has links)
Pyrolysis has been a useful procedure to treat waste-tire, which decomposes waste-tire at high temperature in the absence of oxygen. This thermal decomposition process generates pyrolysis oil, combustible gas, and char, which distribute in liquid phase, gas phase, and solid phase, respectively. Pyrolysis oil and combustible gas are fuels, while char is composed of carbon black and ash. Thus, char would be economically worth while to be treated before reuse. In this study, based on the resistivity difference between carbon black and ash, ash can be removed from char in the principle of electrostatic separation and thus increase the value of char.
In this study, the objective was to separate ash from char by electrostatic separation process, different char including waste-tire pyrolytic char (raw char), low pressure re-pyrolytic char, ZnO-added char (12% ZnO mixed with 600 oC re-pyrolytic cahr) and man-made char (N600 carbon black mixed with 14.5% metallic oxide) were tested. The Electro-Static Separator (ESS) was designed and constructed with two types of discharge electrodes including a needle-plate electrode (NPE) and a needle-bar electrode (NBE) and two kinds of dust feeders to generate either fine or coarse particles.
The results indicated that raw char had higher collection efficiency using the NBE system than the NPE system in the operating voltages of -7 kV to -15 kV because the surface area of the NBE system was less than the NPE system, thus led higher surface charge density for the NBE system than the NPE system, resulting in higher discharge current of the NBE system.
In order to lower resistivity and reduce deposited pyrolysis oil on char, low pressure repyrolysis process was used. Because the removal efficiency of pyrolysis oil is proportional to repyrolysis temperature, more pyrolysis oil can be removed from the surface of char, resulting in more carbon blacks exposed on the char surface as conductive material. Thus, the collection efficiency of 600 oC repyrolytic char was less than that of 400 oC repyrolytic char. Furthermore, because particle charging quantity was proportional to particle size, fine char particles had less collection efficiency than coarse char particles.
However, both raw char and repyrolytic char, the collection efficiency of carbon and ash had similar trends, suggesting that similar percentage of carbon and ash were collected on the plate and penetrated the ESS system. Therefore, the separation efficiency of carbon and ash were similar, same situation was observed for the ZnO-added char.
In order to verify the feasibility of carbon and ash separation by electrostatic separation process, N660 carbon black mixing with 14.5% man-made ash (Al2O3, ZnO and CaO composed) to simulate man-made char, which was further used to proceed the electrostatic separation experiments in this study.
The results indicated that the collection efficiency of man-made char increased with operating voltage, and the ash content seems to increase with voltage. Carbon black is a low resistivity material, which causing sparkover during the experiments, thus operating voltage cannot be regulated more than -8.25 kV. In order to verify the feasibility of carbon black and ash separation by the principle of electrostatic separation, this study applied non-linear regression to model the collection efficiency of man-made char, carbon black and ash, and further simulate the collection efficiency at higher electrical field strength. The simulated results indicated that the maximum collection efficiency of carbon and ash was approached around -10 kV/cm of carbon black and ash and their collection efficiencies were similar. The collection efficiency of ash was close to the ash content of man-made char (the collection efficiency of ash equal to the collected ash per mass of injected char), suggesting that most injected ash was collected by the ESS system. In addition, the ash content of penetration char was also simulated, the modeling results showed that the ash content of penetrated char were lower than 2%, while was relatively lower than the raw man-made char, and more than 75% injected char could penetrate the ESS system during the operation procedure. According to the modeling results, solid-solid separation technology could be more efficient if carbon and ash are independently separate particles, and lower resistivity materials would penetrate the ESS system and higher resistivity materials would be collected by the electrostatic separation process.
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COMPARISON OF YIELD, CALORIFIC VALUE AND ASH CONTENT IN WOODY AND HERBACEOUS BIOMASS USED FOR BIOENERGY PRODUCTION IN SOUTHERN ONTARIO, CANADAMann, John 10 September 2012 (has links)
Recently, the use of biomass to produce energy has resulted in evaluating each potential biomass species individually, and primarily in terms of yield potentials. However, discrepancies between species yield caused by varying site conditions and varying fertilization regimes between studies do exist. Therefore, this study attempts to address some of these discrepancies by growing multiple species simultaneously on marginal land with zero fertilization. The yield and fuel characteristics of the four most commonly used biomass feedstocks (Miscanthus, switchgrass, willow and poplar) in southern Ontario, along with one herbaceous polyculture, were investigated. Species' influence on microclimatic modifications was quantified during the 2010 and 2011 growing seasons in order to understand its impact on biomass yields. Yield data was gathered for each species treatment for both growing seasons. Few significant differences were found between species during establishment. Fuel characteristics analyses including, gross calorific value, ash (%), and an elemental ash analysis were completed during 2010 and 2011. The differences between the combustion properties of the grass species and the woody species were obvious, but neither could be conclusively determined as universally better than the other. Yield and fuel characteristics change as plants mature, therefore research should be continued in future years once plots are fully established to determine which species are best suited for bioenergy production in Southern Ontario. This will help growers and energy producers focus on crops that have the most potential in achieving environmental sustainability and economic viability. / OMAFRA
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Estimação do teor de cinzas da camada I do carvão do leão através da reflectância utilizando a teoria Kubelka-MunkJesus, Leandro Gustavo Mendes de January 2014 (has links)
O principal parâmetro de avaliação da qualidade de carvões para uso na geração de energia termoelétrica é o percentual de cinzas. Em uma planta de beneficiamento, saber o percentual de cinzas da alimentação, concentrado e rejeito é de suma importância para os ajustes nos equipamentos de concentração. No caso do carvão da camada I1 do depósito mineral do Leão a janela de tempo entre o ponto mais adequado para amostragem e o fim da campanha de beneficiamento não propicia que se conheça o teor de cinzas da alimentação do processo de beneficiamento. Em virtude disso, este trabalho tem como objetivo de fornecer uma estimativa confiável do teor de cinzas da alimentação para propiciar a aplicação na planta de beneficiamento. Para esse intento utilizou-se a teoria de Kubelka-Munk que por meio de sua expressão matemática transforma a reflectância em uma grandeza aditiva que propicia a estimativa das porcentagens de matéria orgânica e mineral contida no carvão devido a diferença de reflectância entre esses materiais. Como resultado final foram gerados diversos modelos com intuito de verificar qual deles se adaptava melhor aos dados. Por fim, foi possível concluir que há possibilidade de estimar o teor de cinzas de carvão por meio da reflectância e com confiabilidade de 96,78% que toda a leitura agrega um erro máximo de ± 5% para o melhor modelo. / The main parameter in quality evaluation of coals employed in power generation is the ash content. In a beneficiation plant, knowing the ash content of the feed, concentrate an tailings is mandatory to set up the concentration equipment. In the case of the I1 coal seam of Leão’s deposit the time window between sampling routine and beneficiation routine does not allow to know the feed ash content before the beneficiation process. By this reason, this work aims to provide a reliable estimative of the feed ash content to propitiate its application in the beneficiation plant. For this purpose it was used Kubelka-Munk’s theory that, by using a mathematic expression, transforms reflectance into a additive quantity which allows to estimate mineral and organic matter present in coal by the difference of reflectance between these materials. As result, it was generated several models in order to analyze which one is better suited to the data. Finally, as a conclusion, it is possible to infer the ash content of coal by reflectance with confidence of 96,78% that all measure brings up a maximum error of ± 5% for the best model.
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Estimação do teor de cinzas da camada I do carvão do leão através da reflectância utilizando a teoria Kubelka-MunkJesus, Leandro Gustavo Mendes de January 2014 (has links)
O principal parâmetro de avaliação da qualidade de carvões para uso na geração de energia termoelétrica é o percentual de cinzas. Em uma planta de beneficiamento, saber o percentual de cinzas da alimentação, concentrado e rejeito é de suma importância para os ajustes nos equipamentos de concentração. No caso do carvão da camada I1 do depósito mineral do Leão a janela de tempo entre o ponto mais adequado para amostragem e o fim da campanha de beneficiamento não propicia que se conheça o teor de cinzas da alimentação do processo de beneficiamento. Em virtude disso, este trabalho tem como objetivo de fornecer uma estimativa confiável do teor de cinzas da alimentação para propiciar a aplicação na planta de beneficiamento. Para esse intento utilizou-se a teoria de Kubelka-Munk que por meio de sua expressão matemática transforma a reflectância em uma grandeza aditiva que propicia a estimativa das porcentagens de matéria orgânica e mineral contida no carvão devido a diferença de reflectância entre esses materiais. Como resultado final foram gerados diversos modelos com intuito de verificar qual deles se adaptava melhor aos dados. Por fim, foi possível concluir que há possibilidade de estimar o teor de cinzas de carvão por meio da reflectância e com confiabilidade de 96,78% que toda a leitura agrega um erro máximo de ± 5% para o melhor modelo. / The main parameter in quality evaluation of coals employed in power generation is the ash content. In a beneficiation plant, knowing the ash content of the feed, concentrate an tailings is mandatory to set up the concentration equipment. In the case of the I1 coal seam of Leão’s deposit the time window between sampling routine and beneficiation routine does not allow to know the feed ash content before the beneficiation process. By this reason, this work aims to provide a reliable estimative of the feed ash content to propitiate its application in the beneficiation plant. For this purpose it was used Kubelka-Munk’s theory that, by using a mathematic expression, transforms reflectance into a additive quantity which allows to estimate mineral and organic matter present in coal by the difference of reflectance between these materials. As result, it was generated several models in order to analyze which one is better suited to the data. Finally, as a conclusion, it is possible to infer the ash content of coal by reflectance with confidence of 96,78% that all measure brings up a maximum error of ± 5% for the best model.
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Porovnání vlastností alternativních pelet / Comparison of properties of alternative pelletsJansa, Oldřich January 2011 (has links)
This thesis deals with the alternative pellets and the means of production from raw material to final customer. The theoretical part deals with different techniques and manufacturing technologies used. Furthermore, the work deals with Czech and European legislation in the field of fuel pellets. The practical part deals with measuring and comparing the properties of selected standard pellets.
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Real-time characterization of fuel by Near-Infrared spectroscopy : Quantitative measurements of moisture content, ash content, heating value, and elemental compositions in solid biofuel mixturesEdlund, Kajsa, Shahnawazi, Ali Ahmad January 2021 (has links)
The global energy demand supplies mainly from fossil fuels, which is neither sustainable nor environmentally friendly and aims to global warming. Therefore, both more investments in renewable energy sources such as bioenergy are required, as well as new technologies such as carbon capture and storage (CCS) to handle the emissions from existing combined heat and power (CHP) plants. In this degree project, the focus is to determine the moisture content, ash content, heating value, and elemental compositions of solid biofuel mixtures in real-time by utilizing the optical technique of near-infrared (NIR) spectroscopy. A total number of 150 samples of solid biofuel mixtures were prepared and illuminated by NIR light. All spectra of the samples were recorded in a wavenumber range of 12000 cm-1 – 400 cm-1 in a dish on a turn table which was in a moving mode with a speed of 0.5 m/s. Each sample was scanned three times to avoid, or at least minimize the deviation of the spectra and the samples were mixed between each scan to get more reliable representative spectra data. Partial least square regression models were created to analyze the spectra data. A data split was done randomly, 100 for calibration and 50 for validation. Then the data was pre-processed with different methods including multiplicative scatter correction (MSC), standard normal variate (SNV), Savitzky-Golay 1st derivative (SG 1st), Savitzky-Golay 2nd derivative (SG 2nd), and orthogonal signal correction (OSC) to reduce noise and scatter effect. The results of NIR spectra treated by OSC method obtained , RMSE and SE of 0.900, 2.241 and 2.204, respectively for prediction of moisture content, 0.424, 0.913 and 0.922 for prediction of ash content, 0.640, 0.370 and 0.368 for prediction of heating value, respectively. The obtained prediction of , RMSE and SE were 0.687, 0.066 and 0.058 for nitrogen, 0.636, 0.361 and 0.364 for carbon, 0.483, 0.269 and 0.270 for hydrogen, respectively. As the results shows, these models to predict the ash content and hydrogen content has a lower accuracy than what is expected in process modeling while the prediction of moisture content has the highest accuracy.
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Weiterentwicklung der Kohle-Online-Analytik mittels radiometrischer Messmethoden im Rheinischen BraunkohlenrevierSchüngel, Michael 24 July 2017 (has links) (PDF)
Kernthema der Dissertation ist die Weiterentwicklung von Kohle-Online-Messtechniken zur kontinuierlichen Bestimmung, das Brennstoffverhalten in Kraftwerkskesseln beeinflussender anorganischer Kohleinhaltsstoffe im Rheinischen Braunkohlerevier, die geologisch bedingt, natürlichen Schwankungen unterliegen. Im Rahmen dieses Vorhabens wurden die Gammastrahlenabsorptionsverfahren zur Aschegehaltsbestimmung und die Prompte-Gamma-Neutronen-Aktivierungs-Analyse (PGNAA) zur Multielement-Analyse als innovative Messmethoden zur Analyse des gesamten Kohlestroms auf Förderbandanlagen identifiziert, deren Eignung im Rahmen von Voruntersuchungen bestätigt, betrieblich eingeführt und unter Praxisbedingungen optimiert. Dabei wurde die Wechselwirkung zwischen Gamma- und Neutronenstrahlung unterschiedlicher Energien mit Braunkohlen und Fördergurten unterschiedlicher Eigenschaften sowie Einflüsse variierender homogener und inhomogener Elementzusammensetzungen bei verschiedenen Messsystemanordnungen und Förderleistungen auf die Messergebnisse systematisch erfasst und für die Versuchsanlagen in der betrieblichen Praxis umgesetzt. Die Gamma-Absorptionsmethode ist im betrieblichen Einsatz, die Erprobung der PGNAA-Prototypanlage steht bevor.
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Energetické využití netradiční biomasy / Utilization of unconventional biomass for energy productionBoumová, Markéta January 2010 (has links)
Tato diplomová práce se zabývá netradičními druhy biomasy využitelnými v České republice a Španělsku a jejich srovnáním. V prvních kapitolách jsou popsány netradiční druhy biomasy, mezinárodní projekty, smlouvy a legislativa. V následujích kapitolách je rozbor netradičních druhů biomasy zejména vznikajících z potravinářského průmyslu každé země s detailním rozborem a srovnáním zbytků z průmyslového zpracování slunečnice a oliv. V závěru je uděláno celkové srovnání těchto druhů biomasy České republiky a Španělska z aspektů výkupních cen, výhřevností, vlhkosti a množství popelovin.
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