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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Enhancement of the separation of nitrogen from methane in natural gas by means of transition metal complexes encapsulated in aluminosilicate materials

Ashton, Sarah Lindsey January 1998 (has links)
No description available.
2

Auger Reactor Co-Pyrolysis of Southern Pine, Micronized Rubber Powder, and a Food-Grade Polymer under the Influence of Sodium Carbonate and Nickel Oxide Catalysts

Wainscott, Cody 03 May 2019 (has links)
Bio-oil created from biomass sources do not have desirable fuel qualities. Due to their petroleum origins, plastics and micronized rubber powder (MRP) improve oil quality when co-pyrolyzed with biomass. Southern yellow pine, a food grade polymer (FGP) and micronized rubber powder (MRP) were co-pyrolyzed at various ratios in an auger reactor to improve the bio-oil. MRP proved to be the best additive, reducing acids, creating aromatic hydrocarbons, reducing water content, and increasing heating values in created bio-oil, while the FGP led to a formation of a liquid product containing a high concentration of phenolic compounds. To improve these qualities further, nickel oxide and sodium carbonate were added in-vivo to the coeeds. Nickel oxide influenced higher aromatic hydrocarbon production and reduced oxygen formation. Sodium carbonate greatly reduced the concentration of acids and water. Both catalysts improved the creation of unsaturated hydrocarbons, phenol compounds, and enhanced heating values with nickel oxide performing better than sodium carbonate.
3

POTENCIAL ENERGÉTICO DA EICHHORNIA CRASSIPES (AGUAPÉ) E DA PISTIA STRATIOTES (ALFACE D’ÁGUA)

Rosa, Tammy Scarlett Balbina Sales 14 September 2016 (has links)
Made available in DSpace on 2017-07-21T14:32:38Z (GMT). No. of bitstreams: 1 Tammy Sales Rosa.pdf: 1898317 bytes, checksum: 62f560bd48bfd3197dcc87a1edba0877 (MD5) Previous issue date: 2016-09-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Must of the energy consumption in the world comes from non-renewable sources of energy, the main information occurs in nature in a longer time than their consumption and subject of depletion causing negative impacts in its use. Alternative sources are necessary. The use of biomass as fuel material, is widely used and appears as the main substitute for fossil fuels. The purpose of this work is to evaluate the energy potential of macrófitas Eichhornia crassipes (water hyacinth) and Pistia stratiotes (water lettuce) existing in the region of Campos Gerais, Ponta Grossa, Paraná, Brasil. Assessment took place gravimetric design,analysis growth, immediate analysis and determination of the calorific value. The macrophyte water hyacinth and water lettuce showed intermediate energy potential compared biomasses studied today. Immediate analysis did not show satisfactory values when compared to biomass already used. For higher calorific values the average and the productivity of the dry mass values were similar to biomasses already used. The water hyacinth showed characteristic values about water lettuce. / Grande parte do consumo energético do mundo é proveniente de fontes não renováveis de energia, ou seja, sua formação na natureza ocorre em um tempo maior do que o seu consumo, sendo passíveis de esgotamento e causando impactos negativos na sua utilização. Fontes alternativas se fazem necessárias. O uso de biomassa como material combustível é muito utilizado e aparece como principal substituto dos combustíveis fósseis. Portanto este trabalho teve como objetivo, avaliar potencial energético das macrófitas Eichhornia crassipes (aguapé) e Pistia stratiotes (alface d’água) existentes na região dos Campos Gerais, município de Ponta Grossa, Paraná, Brasil. Para avaliação realizou-se dimensionamento gravimétrico, análise de crescimento, análise imediata e determinação do poder calorífico. As macrófitas aguapé ealface d’água apresentaram potencial energético intermediário quando comparadas as biomassas hoje estudadas. A análise imediata apresentou valores não satisfatórios quando comparados a biomassa já utilizada. Para o poder calorífico superior os valores foram médios e para a produtividade da massa seca os valores foram semelhantes às biomassas já utilizadas.O aguapé mostrou valores característicos superiores a alface d’água.
4

Tung (Aleurites fordii) Avaliação do potencial energético do fruto e do biodiesel / Tung (Aleurites fordii) Evaluation of the energetic potential of the fruit and biodiesel

Zornitta, Nelson 17 February 2014 (has links)
Made available in DSpace on 2017-07-10T15:14:30Z (GMT). No. of bitstreams: 1 DissertacaoNelsonZornitta.pdf: 1964043 bytes, checksum: 6e00e96d6c14cfef884c7e8f887042f3 (MD5) Previous issue date: 2014-02-17 / The oil produced by the Tung s fruit (Aleurites fordii) is already inserted in the market due to its numerous applications that comprehends drying qualities reaching the packing production. In this study, it was evaluated the energetic potential of the Tung s fruit, oil and biodiesel to fill the gap of unpublished information. The fruits were harvested in Cascavel, state of Paraná, Brazil, and they were kept in a shadow place for drying in a period of six months. When the fruits were sliced it was separated the pericarp, the seed coat and the seed. The experiments were performed at the Unioeste campus. The results obtained show that the moisture of crushed seeds presented a value of 3.81% and the seed that was not crushed, 4.5%. The average yielding obtained from the oil extracted from the seeds using the Soxhlet equipment presented a value of 50.6% with a standard deviation of 1.22%; the value of density obtained using the pycnometer was 931.5 g L-1; the value of acid index obtained by titration was 4.5 mg KOH g-1. Biodiesel was produced using the methyl route through a basic catalysis with potassium hydroxide, presenting a density value of 910.8 g L-1 and the specific mass 909.2 kg m-3 at 20 ° C, acid index of 0.473 mg KOH g-1 and flash point of 178 °C. The energetic potential of the Tung was evaluated by the determination of the higher heating value of the mass, oil and biodiesel and from the development of the specific Tung s biodiesel consumption and its blends with diesel. The heating values obtained using a Combustion Calorimeter, e2k, are presented as follow: 9209 kcal kg-1 for the extracted oil; 9117 kcal kg-1 for the commercial oil; 9149 kcal kg-1 for the biodiesel; 7017 kcal kg-1 for the crushed seed; 4840 kcal kg-1 for the pie after extraction; 4608 kcal kg-1 for the pericarp; and 3592 kcal kg-1 for the seed coat. The value of the heating value for the entire dry fruit was estimated through by calculation and the value obtained was 4818 kcal kg-1. The values of ash level are shown as follow: 1.80% for the crushed seed; 2.24% for the pie after extraction of oil; 0.66% for the pericarp; and 5.80% for the seed coat. The results obtained confirms the high level of oil in the Tung s seeds; moreover, the biomass of the Tung s fruits in natura show considerable values for the heating value (LHV > 1850 kcal kg-1) and when it is put together to the low level of ash (< 8%) the Tung seed can be considered a renewable source of clean energy / O fruto do tungue (Aleurites fordii) produz um óleo de grande aceitação no mercado pelas inúmeras aplicações que vão das qualidades secativas a produção de embalagens e revestimentos. Neste estudo avaliou-se o potencial energético do fruto, do óleo e do biodisel do tungue para suprir a falta de informações publicadas. Os frutos foram colhidos em Cascavel, Paraná, Brasil e guardados a sombra para secagem por um período de seis meses. Na abertura dos frutos foram separados o pericarpo, a testa da semente e o endosperma. Os experimentos foram realizados no campus da Unioeste de Cascavel. A úmidade das sementes foi determinada pelo método destrutivo indireto por estufa a ar; para as sementes quebradas foi de 3,81% e para as sementes inteiras de 4,5%. O rendimento médio do óleo extraído das sementes por Soxhlet foi de 50,6% com desvio padrão de 1,22%; a densidade, medida com picnômetro, foi 931,5 g L-1; o índice de acidez obtido por titulação foi de 4,5 mg KOH g-1. O biodiesel foi produzido pela rota metílica com catálise básica por hidróxido de potássio, apresentando densidade de 910,8 g L-1 e a massa específica 909,2 kg m-3 a 20 °C; o índice de acidez foi de 0,473 mg KOH g-1 e ponto de fulgor de 178 °C. O potencial energético do tungue foi medido através da determinação do poder calorífico superior da biomassa, do óleo e do biodiesel e do levantamento da curva do consumo específico do biodiesel de tungue e de blendas com o diesel. Com um calorímetro a combustão, modelo e2k foram medidos o poder calorífico superior das partes do fruto, do óleo extraído, do óleo comercial e do biodiesel obtendo-se: para o óleo extraído 9209 kcal kg-1; para o óleo comercial 9117 kcal kg-1; para o biodiesel 9149 kcal kg-1; para a semente triturada 7017 kcal kg-1; para a torta após a extração 4880 kcal kg-1; para o pericarpo 4608 kcal kg-1; e para a testa da semente 3592 kcal kg-1. Estimou-se através de cálculo para o fruto inteiro seco 4818 kcal kg-1. O teor de cinzas encontrado foi: para a semente triturada 1,80%; para a torta após a extração do óleo 2,24%; para pericarpo 0,66%; e para a testa da semente 5,80%. Os resultados obtidos confirmam o alto índice de óleo nas sementes de tungue; a biomassa dos frutos de tungue apresentam apreciáveis valores de poder calorífico in natura (PCI>1850 kcal kg-1) que associados aos baixos teores de cinzas (<8%) podem ser consideradas fontes renováveis de energia limpa
5

COMPARISON OF YIELD, CALORIFIC VALUE AND ASH CONTENT IN WOODY AND HERBACEOUS BIOMASS USED FOR BIOENERGY PRODUCTION IN SOUTHERN ONTARIO, CANADA

Mann, 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
6

Análise energética do processo experimental de produção de biodiesel a partir de óleo de frango

Bonometo, Ricardo Pacheco [UNESP] 01 September 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-09-01Bitstream added on 2014-06-13T19:52:22Z : No. of bitstreams: 1 bonometo_rp_me_botfca.pdf: 282254 bytes, checksum: a2dad01e970c5bd5c29c202bdf98cbdf (MD5) / Atualmente há uma grande preocupação mundial com o esgotamento e o alto custo de exploração das reservas de combustíveis fósseis e, portanto, mais do que nunca, é necessário o aprofundamento do estudo e aproveitamento de fontes alternativas que possam ser utilizadas com eficiência energética, preços adequados e com baixo impacto ambiental. De acordo com estas premissas, o biodiesel é um combustível com boas perspectivas de atender uma demanda crescente, pois além de substituir o óleo diesel, pode ser obtido a partir de várias fontes primárias de origem animal e vegetal. O Brasil se destaca na utilização das fontes alternativas de energia com o uso do etanol e, nos últimos anos vem incentivando a ampliação de sua matriz energética a partir das fontes alternativas, na qual o biodiesel passa a ter uma importância estratégica dentro da área de agronegócios. O biodiesel é um combustível que pode substituir o diesel, que é um derivado do petróleo; é um éster produzido na reação de transesterificação de óleos vegetais, goduras animais que, na presença de um álcool, metanol ou etanol, e um catalisador, são convertidos em ácidos graxos e, resultam, em ésteres com glicerol como subproduto. Com o avanço da utilização destes biocombustíveis são necessárias pesquisas que visam melhorar a qualidade e viabilidade técnica dos mesmos, sendo que, o balanço energético é um dos parâmetros mais adequado para definir a viabilidade técnica, pois estabelece a relação entre o total de energia contida no combustível e aquela investida em todo o processo de produção. O objetivo deste trabalho foi analisar energeticamente o processo de produção de biodiesel a partir do óleo dos resíduos descartados na produção de frango. Para a estimativa deste balanço de energia quantificou-se o poder calorífico de alguns... / Nowadays there is a great global concern with the depletion and the high cost of fossil fuel reserves exploitation, more than ever, it is necessary to make a profound study and take advantage of alternative sources that can be used with energy efficiency with an appropriate pricing and with low environmental impact. Under these assumptions, biodiesel is a fuel with good prospects of meeting a growing demand, as well as being a replacement of diesel oil, can be obtained from several primary sources of animal and plant origin. Brazil, which has highlighted in use of alternative energy sources with the use of ethanol and, in recent years, has been encouraging the expansion of its energy matrix in which the biodiesel will have a strategic importance within the agrobusiness area. Biodiesel is a fuel that can replace the diesel,that is a petroleum derivative. It is an ester, produced in the transesterification reaction of vegetable oils and animal greases, that in the presence of an alcohol like methanol or ethanol with an additional catalyst, are converted into fatty acids and result in esters with glycerol as subproducts. The advancement in use of biofuels, some researchs needed improve the quality and feasibility and that energetic balance is one of the most appropriate parameters to define the technical feasibility, since settle the same relationship between of total energy in the biofuel and the total energy invested in the whole production process. The objective of this study was to estimate the final energy balance for the process biodiesel production from oil chicken waste. The energy balance estimation was quantified in calorific value according the energy expenditure by calorimetric bomb method. The study was conducted in CEDETEC - Center for Development and Dissemination of Technology, Department of Agronomy... (Complete abstract click electronic access below)
7

Análise energética do processo experimental de produção de biodiesel a partir de óleo de frango /

Bonometo, Ricardo Pacheco. January 2009 (has links)
Orientador: José Roberto Corrêa Saglietti / Banca: Osmar de Carvalho Bueno / Banca: Reginaldo F. dos Santos / Resumo: Atualmente há uma grande preocupação mundial com o esgotamento e o alto custo de exploração das reservas de combustíveis fósseis e, portanto, mais do que nunca, é necessário o aprofundamento do estudo e aproveitamento de fontes alternativas que possam ser utilizadas com eficiência energética, preços adequados e com baixo impacto ambiental. De acordo com estas premissas, o biodiesel é um combustível com boas perspectivas de atender uma demanda crescente, pois além de substituir o óleo diesel, pode ser obtido a partir de várias fontes primárias de origem animal e vegetal. O Brasil se destaca na utilização das fontes alternativas de energia com o uso do etanol e, nos últimos anos vem incentivando a ampliação de sua matriz energética a partir das fontes alternativas, na qual o biodiesel passa a ter uma importância estratégica dentro da área de agronegócios. O biodiesel é um combustível que pode substituir o diesel, que é um derivado do petróleo; é um éster produzido na reação de transesterificação de óleos vegetais, goduras animais que, na presença de um álcool, metanol ou etanol, e um catalisador, são convertidos em ácidos graxos e, resultam, em ésteres com glicerol como subproduto. Com o avanço da utilização destes biocombustíveis são necessárias pesquisas que visam melhorar a qualidade e viabilidade técnica dos mesmos, sendo que, o balanço energético é um dos parâmetros mais adequado para definir a viabilidade técnica, pois estabelece a relação entre o total de energia contida no combustível e aquela investida em todo o processo de produção. O objetivo deste trabalho foi analisar energeticamente o processo de produção de biodiesel a partir do óleo dos resíduos descartados na produção de frango. Para a estimativa deste balanço de energia quantificou-se o poder calorífico de alguns... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Nowadays there is a great global concern with the depletion and the high cost of fossil fuel reserves exploitation, more than ever, it is necessary to make a profound study and take advantage of alternative sources that can be used with energy efficiency with an appropriate pricing and with low environmental impact. Under these assumptions, biodiesel is a fuel with good prospects of meeting a growing demand, as well as being a replacement of diesel oil, can be obtained from several primary sources of animal and plant origin. Brazil, which has highlighted in use of alternative energy sources with the use of ethanol and, in recent years, has been encouraging the expansion of its energy matrix in which the biodiesel will have a strategic importance within the agrobusiness area. Biodiesel is a fuel that can replace the diesel,that is a petroleum derivative. It is an ester, produced in the transesterification reaction of vegetable oils and animal greases, that in the presence of an alcohol like methanol or ethanol with an additional catalyst, are converted into fatty acids and result in esters with glycerol as subproducts. The advancement in use of biofuels, some researchs needed improve the quality and feasibility and that energetic balance is one of the most appropriate parameters to define the technical feasibility, since settle the same relationship between of total energy in the biofuel and the total energy invested in the whole production process. The objective of this study was to estimate the final energy balance for the process biodiesel production from oil chicken waste. The energy balance estimation was quantified in calorific value according the energy expenditure by calorimetric bomb method. The study was conducted in CEDETEC - Center for Development and Dissemination of Technology, Department of Agronomy... (Complete abstract click electronic access below) / Mestre
8

Stanovení rozlohy porostů rychle rostoucích dřevin pro udržitelné zásobování teplem malé obce (Úsilné u Českých Budějovic) / Determination of the size of fast-growing woody plants for sustainable heat supply small communities (Úsilné u Českých Budějovic)

Kalaš, Vladislav January 2009 (has links)
This diploma thesis addresses the issues regarding fast-growing wood (hereinafter referred to as FGW). Its goal is to analyze the energy intensity of fuels in a selected municipality, namely Úsilné u Českých Budějovic, and to determine the necessary agricultural land expanse for the eventual introduction of FGW vegetation which could replace the usual energy sources in the future.
9

Plasma biomass gasification in a 15 kW pilot facility

Maseko, Keabetswe January 2020 (has links)
Plasma gasification experiments were conducted on sucrose and crushed macadamia nutshells. The pilot-scale plasma gasification system used comprises a 15 kW DC plasma torch fitted to a 5 L gasification reactor. The DC plasma torch has an efficiency of ~30 % with most of the energy lost in the torch anode. For the macadamia nutshells, the plasma input-power was set at 9, 11 and 14 kW. At each power input setting, four different feed rates were investigated, namely 0.5, 0.7, 1.04 and 1.14 kg/h. It was observed that as the power increases, conversion increases from 48 % at 9 kW to higher than 80 % at 14 kW. It was also observed that higher mass feed rates increase the conversion. The lower heating values of the syngas produced during gasification increased with higher power inputs and higher feed rates. At a feed rate of 1 kg/h, the maximum calorific power value was 3.45 kW, at a torch setting of 14 kW. The highest power values obtained was slightly more than 4 kW. The effect of equivalence ratio (ER) was evaluated on the plasma gasification of sucrose. ER values of 1 and 2 were investigated. With an ER of 1, the CO/H2 ratio was 1.8 and the CO/CO2 ratio was 109. With an ER of 2, the CO/H2 ratio was 1.73, and the CO/CO2 ratio 18. As expected, an increase in ER enhances the formation of CO2. A low ER thus results in higher syngas quality. At equivalent conditions the homogenous, crystalline sucrose yielded a CO/CO2 ratio of 109, significantly higher than the 29 for plasma gasification of the macadamia nut shells. A contributing factor to having better quality syngas, was the smaller the average particle diameter of the sucrose, 0.4 mm, compared to the 10 mm of the crushed macadamia nut shells was. Another contributing factor could be that the available carbon in the macadamia nut shells structure are more strongly bonded than in sucrose. For additional insight, kinetic data for the pyrolysis of sucrose, fructose and glucose were obtained using a TGA-FTIR hyphenated system, at much lower heating rates than anticipated in plasma system, and TGA-DTG experiments on macadamia nut shells. Dynamic studies were performed on sucrose, fructose and glucose at heating rates of 5, 10, 15, 20 and 50 °C/min in an atmosphere of nitrogen flowing at 50 mL/min, and for the macadamia shell at heating rates of 5, 10 and 20 °C/min in an atmosphere of nitrogen flowing at 50 mL/min. The sugars yielded 80 % to 85 % conversion into gaseous products, while the conversion of the shells approached 90 %; the residue was biochar. The FTIR spectra showed the major products that form from the pyrolysis of sugars to be CO2, H2O, along with large quantities C-H-O-containing compounds, amongst them C5H4O2 and C6H6O3. The latter two compounds are probably condensible. / Dissertation (MEng)--University of Pretoria, 2020. / Chemical Engineering / MEng / Unrestricted
10

Criteria for solid recovered fuels as a substitute for fossil fuels – a review

Beckmann, Michael, Pohl, Martin, Bernhardt, Daniel, Gebauer, Kathrin 05 June 2019 (has links)
The waste treatment, particularly the thermal treatment of waste has changed fundamentally in the last 20 years, i.e. from facilities solely dedicated to the thermal treatment of waste to facilities, which in addition to that ensure the safe plant operation and fulfill very ambitious criteria regarding emission reduction, resource recovery and energy efficiency as well. Therefore this contributes to the economic use of raw materials and due to the energy recovered from waste also to the energy provision. The development described had the consequence that waste and solid recovered fuels (SRF) has to be evaluated based on fuel criteria as well. Fossil fuels – coal, crude oil, natural gas etc. have been extensively investigated due to their application in plants for energy conversion and also due to their use in the primary industry. Thereby depending on the respective processes, criteria on fuel technical properties can be derived. The methods for engineering analysis of regular fuels (fossil fuels) can be transferred only partially to SRF. For this reason methods are being developed or adapted to current analytical methods for the characterization of SRF. In this paper the possibilities of the energetic utilization of SRF and the characterization of SRF before and during the energetic utilization will be discussed.

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