A fundamental understanding of the process of devolatilization requires extensive knowledge of not only the intrinsic properties of the parent coal and its subsequent formed products (tars, gases and chars), but also its characteristic reaction rate behaviour. Devolatilization behaviour has been extensively addressed in literature with the use of powdered coal samples, which normally do not adhere to particle size constraints of coal conversion processes utilizing lump coal. The aim of this investigation was therefore to assess the devolatilization behaviour (with respect to product yield and -quality; and reaction rate modelling) of four typical South African coals (UMZ, INY, G#5 and TSH) confined to the large particle regime. All four coals were found to be bituminous in rank, with vitrinite contents ranging between 24.4 vol.% and 69.2 vol.% (mineral matter free basis). Two were inertinite-rich coals (UMZ and INY) and the other two were vitrinite-rich coals (G#5 and TSH). From thermoplasticity measurements it was evident that only coal TSH displayed extensive thermoplastic behaviour, while a comparison between molecular properties confirmed the higher abundance of poly-condensed aromatic structures (aromaticity of 81%) present in this coal. Product evolution was evaluated under atmospheric conditions in a self-constructed, large particle, fixed-bed reactor, on two particle sizes (5 mm and 20 mm) at two isothermal reactor temperatures (450°C and 750°C) using a combination of both GC and MS techniques for gas species measurement, while standard gravimetric methods were used to quantify tar- and char yield respectively. Elucidation of tar- and char structural features involved the use of both conventional- and advanced analytical techniques. From the results it could be concluded that temperature was the dominating factor controlling product yield- and quality, with significant increases in both volatile- and gas yield observed for an increase in temperature. Tar yields ranged between 3.6 wt.% and 10.1 wt.% and increased in the order UMZ < INY < TSH < G#5, with higher tar yields obtained for coal G#5, being ascribed to larger abundances of vitrinite and liptinite present in this coal. For coal TSH, lower tar yields could mainly be attributed to the higher aromaticity and extensive swelling nature of this coal. Evolved gases were found to be mainly composed of H2, CH4, CO and CO2, low molecular weight olefins and paraffins; and some C4 homologues. Advanced analytical techniques (NMR, SEC, GC-MS, XRD, etc.) revealed the progressive increase of the aromatic nature of both tars and chars with increasing temperature; as well as subsequent differences in tar composition between the different parent coals. In all cases, an increase in devolatilization temperature led to the evolution of larger amounts of aromatic compounds such as alkyl-naphthalenes and PAHs, while significant decreases in the amount of aliphatics and mixed compounds could be observed. From 13C NMR, HRTEM and XRD carbon crystallite results it was clear that an increase in temperature led to the formation of progressively larger, more aromatic and structurally orientated polycondensed carbon structures. Reaction rate studies involved the use of non-isothermal (5-40 K/min) and isothermal (350- 900°C) thermogravimetry of both powdered (-200 μm) and large particle samples (20 mm) in order to assess intrinsic kinetics and large particle rate behaviour, respectively. Evaluation of the intrinsic kinetic parameters of each coal involved the numerical regression of non-isothermal rate data in MATLAB® 7.1.1 according to a pseudo-component modelling philosophy. Modelling results indicated that the intrinsic devolatilization behaviour of each coal could be adequately described by using a total number of eight pseudo-components, while reported activation energies were found to range between 22.3 kJ/mol and 244.3 kJ/mol. Description of the rate of large particle devolatilization involved the evaluation of a novel, comprehensive rate model accounting for derived kinetics, heat and mass transport effects, as well as physical changes due to particle swelling/shrinkage. Evaluation of the proposed model with the aid of the COMSOL Multiphysics 4.3 simulation software provided a suitable fit to the experimental data of all four coals, while simulation studies highlighted the relevant importance of not only the effect of particle size, but also the importance of including terms affecting for heat losses due to particle swelling/shrinkage, transport of volatile products through the porous char structure, heat of reaction and heat of vaporization of water. / Thesis (PhD (Chemical Engineering))--North-West University, Potchefstroom Campus, 2013

Research Project (M.R.M.) - Simon Fraser University, 2005. / Research Project (School of Resource and Environmental Management) / Simon Fraser University.

In June 2009, a 2.2 square mile 3-D high resolution seismic reflection survey was shot in southeastern Illinois in the Phillipstown Consolidated oilfield. A well was drilled in the 3-D survey area to tie the seismic to the geological data with a synthetic seismogram from the sonic log. The objectives of the 3-D seismic survey were three-fold: 1.) To image and interpret faulting of the Herald-Phillipstown Fault using drillhole-based geological and seismic cross-sections and structural contour maps created from the drillhole data and seismic reflection data, 2.) To test the effectiveness of imaging the faults by selected seismic attributes, and 3.) To compare spectral decomposition amplitude maps with an isochron map and an isopach map of a selected geologic interval (VTG interval). Drillhole and seismic reflection data show that various formation offsets increase near the main Herald-Phillipstown fault, and that the fault and its large offset subsidiary faults penetrate the Precambrian crystalline basement. A broad, northeast-trending 10,000 feet wide graben is consistently observed in the drillhole data. Both shallow and deep formations in the geological cross-sections reveal small horst and graben features within the broad graben created possibly in response to fault reactivations. The HPF faults have been interpreted as originally Precambrian age high-angle, normal faults reactivated with various amounts and types of offset. Evidence for strike-slip movement is also clear on several faults. Changes in the seismic attribute values in the selected interval and along various time slices throughout the whole dataset correlate with the Herald-Phillipstown faults. Overall, seismic attributes could provide a means of mapping large offset faults in areas with limited or absent drillhole data. Results of the spectral decomposition suggest that if the interval velocity is known for a particular formation or interval, high-resolution 3-D seismic reflection surveys could utilize these amplitudes as an alternative seismic interpretation method for estimating formation thicknesses. A VTG isopach map was compared with an isochron map and a spectral decomposition amplitude map. The results reveal that the isochron map strongly correlates with the isopach map as well as the spectral decomposition map. It was also found that thicker areas in the isopach correlated with higher amplitude values in the spectral decomposition amplitude map. Offsets along the faults appear sharper in these amplitudes and isochron maps than in the isopach map, possibly as a result of increased spatial sampling.

This thesis deals with combustion of lignocelluloses biomass with comparison to cellulose-lignin biomass and with appropriateness of different combustion technologies in the context of the impact on the environment. Furthermore, the thesis deals with content of the heating value in the individual fuels. The heating value capacity was measured experimentally in different kinds of biomass by method of dry distillation and these results were statistically evaluated and and discussed with the findings taken from literature. On the basis of literature data, differences have been discovered in lignocelluloses fuels in terms of calorific value and heating value, calorific values were in average from 15,3 MJ/kg to 16,8 MJ/kg and heating values were 17,5 18,1 MJ/kg. While in cellulose-lignin fuels these differences are not that big and are within values of 19,5 MJ/kg for heating value and an average calorific value is around 18,4 MJ/kg. Measuring of the content of tar and other residual fluid fractions in five the most commonly used bio-fuels from agricultural production (wheat straw, rape straw, hay, energy crops, digestate from biogas station). After statistical evaluation of data, it revealed the difference in content of tar between the wheat straw and digestate (P 0,05; on average 40,48 % for wheat straw and 29,58 % for digestate).

Submitted by Jordan (jordanbiblio@gmail.com) on 2016-10-08T15:28:07Z No. of bitstreams: 1 DISS_2015_Caroline Christiane Garcia do Nascimento.pdf: 1232713 bytes, checksum: b6d9d8ee73c7e1f4a446d459594b5c8e (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2016-10-08T15:50:53Z (GMT) No. of bitstreams: 1 DISS_2015_Caroline Christiane Garcia do Nascimento.pdf: 1232713 bytes, checksum: b6d9d8ee73c7e1f4a446d459594b5c8e (MD5) / Made available in DSpace on 2016-10-08T15:50:53Z (GMT). No. of bitstreams: 1 DISS_2015_Caroline Christiane Garcia do Nascimento.pdf: 1232713 bytes, checksum: b6d9d8ee73c7e1f4a446d459594b5c8e (MD5) Previous issue date: 2016-09-15 / FAPEMAT / A filosofia bergsoniana deriva da reflexão sobre o tempo, na qual exibe a potente e contraditória natureza do real, que é durée: continuidade e diferença articuladas num meio que é ambiente comum da consciência e da vida. O filósofo francês busca construir seu aporte teórico em uma realidade que não ignore os fatos. Compreende que esse acesso toma o caminho de uma realidade interior, constituída por nossa vida psíquica; assim, volta seu olhar a esse acesso privilegiado, procurando compreender sua natureza, antes de investigar a realidade tida como exterior. Aponta que essa vida interior é de natureza temporal: o tempo, enquanto duração, é a qualidade da vida psíquica. Todavia, não é assim que, no geral, as ciências, tanto a física quanto a jovem psicologia de seu período, a entenderam; marcadas pelo determinismo psicofísico, bem como pelas categorias de matematização, acabaram por não reconhecer a verdadeira natureza psíquica, ao confundi-la com o físico, concebendo-a como sendo de natureza espacial. Nesses fluxos de recalcitrância e rupturas epistemológicas, em 6 de abril de 1922, Henri Bergson e Albert Einstein se encontraram na sociedade francesa de Filosofia, em Paris, para discutir o significado da relatividade. Nos anos seguintes, o filósofo e o físico entregaram-se a uma disputa sobre os conceitos de tempo e espaço. Ao recriar o debate, em 2010, Bruno Latour indaga: ―Afinal – a quem pertence nosso tempo e espaço?‖ Essa controvérsia é marcada por duas áreas– a filosofia e a física – que requeriam o poder de discurso através de grandes porta-vozes. A experiência do tempo foi particularmente sensível a esse processo. De um lado, foi dividido entre um tempo quantitativamente espacializado, possibilitando sua mensuração versus um tempo qualitativo vivido, a duração. Por outro ponto, este último foi crescentemente reduzido a um tempo psicológico e, portanto, insignificante para a física, tal como ficou evidenciado na indiferença de Albert Einstein diante do esforço de Henri Bergson em expor os elementos metafísicos que envolvem a teoria da relatividade. Ao explorar a (re)encenação do debate, promovida por Bruno Latour(2010), tomo como proposta a possibilidade de uma terceira experimentação do seu original e não apenas como um mero fac-símile de 1922, possibilitando novas associações e controvérsias marcadas na temática do tempo. Ao aplicar o conceito de tempo espacial à compreensão do modo de ser do psiquismo, Bergson acusa que o tempo homogêneo é uma noção híbrida de tempo e de espaço, a qual surge porque se compreende a duração como homogênea, concepção que, no fundo, não passa de uma representação simbólica e inexata da verdadeira realidade psíquica. / La philosophie bergsonienne dérive de réflexion sur le temps, qui affiche la nature puissante et contradictoire de la réalité qui est durée: la continuité et la différence articulé dans un environnement qui est conscient de l'environnement et de la vie commune. Le philosophe français cherche à construire sa base théorique dans une réalité qui n'ignore pas les faits. Il faut comprendre que cet accès est le chemin d'une réalité intérieure, composé de notre vie psychique; donc son regard vers cet accès privilégié, en cherchant à comprendre leur nature, avant de chercher à étudier la réalité vue à l'extérieur. Souligne que cette vie intérieure est de nature temporelle: le temps, tandis que la durée est la qualité de la vie psychique. Cependant, il n'est pas si, en général, les sciences, à la fois physique et la psychologie de la jeune pour comprendre leur période; marqué par le déterminisme psychophysique ainsi que les catégories de la mathématisation, finalement pas reconnaître la vraie nature psychique de la confondre avec la physique, la compréhension qu'il est de nature spatiale. Ces flux récalcitrant et ruptures épistémologiques chez 6 Avril 1922, Henri Bergson et Albert Einstein se sont réunis dans la société française de philosophie à Paris pour discuter de la signification de la relativité. Dans les années suivantes, le philosophe et physicien livrés à un différend sur les concepts de temps et d'espace. En recréant le débat en 2010, Bruno Latour demande: «Après tout - Qui est propriétaire de notre temps et l'espace?" Cette controverse est marquée par deux domaines, à savoir: - la philosophie et exigeant physiquement le pouvoir de la parole à travers le grand l'expérience de porte-parole. temps était particulièrement sensible à ce processus. d'un côté, a été divisé entre un temps spatialisé quantitativement, ce qui permet sa mesure par rapport à un temps qualitatif vécu en longueur. sur un autre point, celui-ci a été de plus en plus réduite à une temps psychologique et donc insignifiante pour la physique, comme cela a été démontré par l'indifférence d'Albert Einstein en avant l'effort de Henri Bergson à exposer les éléments métaphysiques relevant de la théorie de la relativité. Exploration de la (re) mise en scène du débat organisé par Bruno Latour (2010), a proposé que je prends comme un tiers de leur procès en première instance et non comme une simple fac-similé de 1922, permettant à de nouvelles associations et controverses ont marqué le thème du temps. En appliquant le concept de l'espace-temps de comprendre le mode d'être de la psyché, qui accuse Bergson temps homogène est une notion hybride de temps et d'espace qui se pose parce que la durée est conçue comme conception homogène que le fond est juste une représentation inexactes et symbolique de la vraie réalité psychique.

The topic of master´s thesis is atmosferic gasification of biomass by the addition of oxygen and steam. The theoretical part is devoted to the description of biomass, process of gasification, kinds of gasification reactor and product gas. Further experiments are devised depending on the gasification medium and output temperature. In this case, the key aspect is the steam addition control. In the practical part, these experiments are performed in a fluidized bed reactor. Resulting values from samples of gas and tar are subsequently processed and evaluated.

Disertation thesis deals with development of hot dolomite filter for the purposes of cleaning of gas polluted by biomass and waste gasification with ash and tar as well as sulphur and chlorine compounds as main pollutants. Gas is then cleaned so that it can be utilized in cogeneration units with combustion engines. This supports advancement of gasification techniques using decentralized power and heat generation especially for design of small scale units. Concrete aims of this thesis are stated in chapter 2. Experimental fluid gasification stend Biofluid 100 has been in operations at Brno University of Technology (BUT) since 2000 and it helps research of biomass and waste gasification. Development of the filter initially utilized needs and experience with the utility during cooperation of BUT and ATEKO Hradec Králové. Water scrubber was used for gas cleaning, however, this method proved to be ineffective. Alternative solutions were considered. Based on literature search, natural catalysts with limestone basis were opted. First part of the thesis presents literature search of this issue. Historic development and description of gasification process are briefly discussed as well as elementary classification of gasification generators. This part is followed by chapters dealing with gas pollutants. Tar – the most significant pollutant – is discussed in a separate chapter which presents tar formation, its classification, characteristics and methods for its removal. Brief summary of requirements on gas properties with respect to its utilization in various applications (especially in cogeneration units) follows. Other part of the literature search part focuses on methods of removal of tar from gas, especially on catalyst methods. Dolomite characteristics, description of dolomite calcination as well as simplified kinetic model of tar cracking using dolomite are presented. Based on literature search, laboratory and verification equipment was designed for the purposes of dolomite properties testing. Equipment description as well as description of experimental stend Biofluid 100 where the experimental tests were carried out can be found in introduction of the experimental part. This is followed by a complete description of pilot equipment design of hot dolomite filter with general description of experimental work process, brief characteristics of the fuel and catalytic material used. Final part of the work comprises of experiment results that were carried out on the pilot equipment. Focus is on efficiency of tar removal in connection with operation temperature, amount of catalytist and material used. Influence of these parameters on gas composition and energy intensity of the whole process under these conditions is mentioned as well. Possibility of autonomous unit operations without electricity heating is briefly outlined. Summary of the most significant results including the potential of future hot dolomite filter development is stated the final part of the thesis.

Due to the continuous growth of energy consumption it is required that development in the energy sector is focused on renewable energy sources. Another possibility how to reduce the consumption of primary energy resources is also searching for new and non-traditional fuels. The biomass is the best and potentially expandable renewable energy source in geographic conditions in the Czech Republic. The energy usage of biomass has experienced a significant increase in recent years, however, even in the big energy power plant. This increase in consumption made mainly from wood biomass a shortage fuel, and it began to raise its price. The consumers of biomass fuel are starting to look for a different type of fuel at this time. Stalk and slightly contaminated biomass are representatives of these non-traditional fuels. Stalks are mostly annual plants grown primarily for subsistence. Waste parts of these plants can be utilized for production of energy. The characteristic temperatures of stalk ash have relatively low values. Sintering of ash in a device is one of the obstacles for energy usage of stalk. Sintering of ash brings a number of operational problems at power facilities. Therefore, the part of a research is dedicated to the melting of ash. The thermal gasification is one of the possibilities how to use biomass efficiently. Gasification can be understood as the thermo-chemical conversion of solid fuel into a different state, in this case the gaseous state. The combustion process is generally more manageable for gaseous fuels. Due to this process ower emissions of undesirable compounds at the output of the combustion device can be achieved. Thermal gasification process takes place under stochiometric access of oxidant. The gas with low heating value is on the outlet from gasification process. The main components of produced gas are hydrogen, carbon monoxide and methane. The final gas contains also a lot of undesirable constituents, which make this gas disadvantaged in energy. These constituents are neutral components that dilute gas only, and pollutants as dust, tar and compounds of sulfur and chlorine. These pollutants complicate further use of the generated gas. The tar compounds together with dust causing build-up on the conveyor pipe and also on the combustion equipment, which are using this generated gas. The quality of produced gas is increases by another reprocessing and cleaning. The purified gas can be used for cogeneration of energy and burn it in internal combustion engines or gas turbines. Other possibility is typical usage for heating according to the needs of technology. The atmospheric fluidized bed gasification reactor Biofluid 100th was built for experimental purposes in the laboratories of the Energy Institute. The thesis is focused on thermal gasification of stalk and other non-traditional fuels in Biofluid device. The aim is to achieve a stable gasification process of stalk and thereby verify the possibility of stalk use as fuel for technology Biofluid. Subsequent aim is design of methods for cleaning the raw gas from the tar compounds. The research is focused on the secondary gas cleaning methods due to the requirements of high purity of the resulting gas.

This interdisciplinary project offers new insights into the reclamation history of two of the most controversial and contaminated sites in Canadian history: the Sydney tar ponds and coke ovens and the Athabasca oil sands. It argues that Canada’s natural resource-dependent economy, combined with jurisdictional uncertainty, created a hesitant, fragmentary site cleanup regime, one that left room for different ideas about landscapes to shape and even distort reclamation’s goals and processes. In the absence of substantive reclamation standards and legislation, researchers struggled to accommodate the unique challenges of the oil sands during the 1960s and 1970s. Ambitious goals for reclamation faltered, and even the most successful examples of oil sands reclamation differed significantly from the pre-extraction environment; reclamation was not restoration. Planners envisioned transforming northeastern Alberta into a managed wilderness and recreation nirvana, but few of these plans were realised. The Sydney tar ponds experience suggests that truly successful reclamation cannot exist unless past injustices are fully acknowledged, reparations made, and a more complete narrative of contamination and reclamation constructed through open deliberation. Reclamation, after all, does not repair history; nor can it erase the past. Effective oil sands reclamation, then, requires a reconsideration of the site’s past and an acknowledgement of the perpetuated vulnerabilities and injustices wrought by development and reclamation.

本文著重在探討現股放空限制與交易成本對期貨錯價之影響。以門檻自我迴歸與續航門檻自我迴歸模型分析期貨錯價之非線性過程，我們發現錯價有回歸平均(mean reversion)的現象。當期貨錯價為正時(套利策略為買現貨賣期貨)，交易量對錯價影響為負；但若期貨錯價為負(套利策略為賣現貨買期貨)，考慮到昂貴的放空成本(costly short sell hypothesis)，交易量對錯價的影響將是較不明確的。 / This article highlights the impact of short selling restrictions and trading costs on the relation on futures mispricing error. Within threshold autoregression model (TAR) and momentum threshold autoregressive model (M-TAR), the influence of optimal arbitrage trading on the mispricing is analyzed. Results concerning trading volume and level, mean reversion in mispricing error, and the model which describes mispricing process better. The empirical evidence suggests that trading costs and short selling costs are influential factors for the mispricing behavior. Moreover, the futures trading volume affects mispricing level significantly.