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Showing 31 to 37 of 37 (0.009 seconds)| 31 |
Impacto dos subprodutos da industrialização do xisto sobre atributos biológicos do solo / Impact of oil shale industrialization byproducts on soil biological attributesDoumer, Marta Eliane 31 March 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The impact of using oil shale byproducts in soil on biological activity is an aspect still little
known. The aim of this work was to evaluate the oil shale byproducts impact on soil
biological attributes. In 2010, experiments were conducted on soil Hapludalf under laboratory
conditions and field. In the laboratory, the treatments consisted of seven different rates (0,
300, 450, 600, 750, 1500 and 3000 kg ha-1) of oil shale ash (OSA), calcareous of shale (CS)
and fragments of shale (FS). In the field, in two crops of beans (Phaseolus vulgaris L.) in notillage
system, the treatments were composed of the OAS, with four rates (0, 750, 1,500 and
3,000 kg ha-1) in combination with mineral fertilizer (NPK) and one treatment with only a
single rate of OSA (1,500 kg ha-1). Other control treatment was beans cultivated without OSA
and without NPK. The evaluations were: CO2 evolution, microbial biomass carbon (MBC),
soil enzyme activity (acid phosphatase, arylsulfatase, β-glucosidase, urease, fluorescein
diacetate hydrolysis, dehydrogenase) and ecotoxicological test. In the laboratory study, the
data show a low degradability of organic fraction of solid byproducts of the oil shale
industrialization. The application of the OAS reduces CO2 emissions without reducing the
CBM. The OSA does not cause negative impacts on soil enzymatic activity even when
reapplied to the soil at increasing rates. The results obtained with the enzymes activity under
field conditions after two applications of OAS, combined with the results of MBC, the
metabolic quotient (qCO2) and ecotoxicological test indicate that the solid byproducts of the
oil shale industrialization (OSA, CS and FS) does not cause the biological degradation of soil. / O impacto do uso de subprodutos do xisto no solo sobre a atividade biológica é um aspecto
ainda pouco conhecido. O objetivo do presente trabalho foi o de avaliar o impacto da
aplicação dos subprodutos do xisto sobre atributos biológicos do solo. No ano de 2010 foram
conduzidos experimentos em solo Argissolo Vermelho distrófico arênico sob condições de
laboratório e de campo. No laboratório, os tratamentos consistiram da aplicação ao solo de
sete diferentes doses (0, 300, 450, 600, 750, 1500 e 3.000 kg ha-1) de xisto retortado (XR),
calcário de xisto (CX) e finos de xisto (FX). No campo, em dois cultivos de feijão (Phaseolus
vulgaris, L.) em sistema plantio direto, os tratamentos avaliados foram compostos pelo XR,
sendo quatro doses crescentes (0, 750, 1.500 e 3.000 kg ha-1) em combinação à adubação
mineral (NPK) e uma dose isolada com somente XR (1.500 kg ha-1). Além desses, foi
avaliado o tratamento sem XR e sem NPK. As avaliações realizadas foram: evolução de CO2,
carbono da biomassa microbiana (CBM), atividade enzimática do solo (fosfatase ácida,
arilsulfatase, β-glicosidase, urease, hidrólise do diacetato de fluoresceína, desidrogenase) e
teste de ecotoxicidade. No estudo laboratorial, foi observada uma baixa degrabilidade da
fração orgânica dos subprodutos sólidos da industrialização do xisto. A aplicação do XR ao
solo reduz a emissão de CO2 sem reduzir o CBM. O XR mesmo quando reaplicado em doses
crescentes ao solo não causa impactos negativos sobre a atividade enzimática do solo. Os
resultados obtidos com as enzimas em condições de campo, após duas aplicações de XR,
aliados aos resultados de CBM, do quociente metabólico (qCO2) e do teste ecotoxicológico
indicam que os subprodutos sólidos da industrialização do xisto (XR, CX e FX) não
provocam a degradação biológica do solo.
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Unconventional futures : anticipation, materiality, and the market in oil shale developmentKama, Kärg January 2013 (has links)
This thesis offers a political geography of unconventional energy development through a study of a particular fossil fuel resource called oil shale. Having long occupied a critical place in the politics and economy of certain states, most notably in Estonia, oil shale is now widely known as an ‘unconventional’ resource that is yet to become technically possible, commercially viable and socially acceptable to exploit. Following the movement through which oil shale becomes both unconventional and conventional, the thesis traces the resource through a series of geo-scientific, economic and political interventions. This study is based on analysis of technical literature and policy documents along with ethnographic fieldwork, interviews, and site visits conducted in Estonia, Colorado, Utah, Jordan, London and Brussels. Drawing together relational accounts of natural resources in political ecology and economic geography with insights from Science and Technology Studies, this project both contributes to critical research on the carbon economy and to recent debates on the concepts of materiality, anticipation, and marketization in social sciences. The thesis proposes a relational conceptualization of resource materiality, situating oil shale in multiple and conflicting forms which derive from geographically disparate practices in both resource assessment and technological development. The future of oil shale exploitation is not pre-determined by the process of global resource decline, nor is it precluded by international demands to move towards lower-carbon futures. Rather, it is determined through the conjunction of different future-oriented economic and political calculations that are entangled with resource materials and associated technological systems. Developing a non-essentialist account of markets as socio-technically distributed arrangements, the thesis argues that these rival calculations influence the design of market rules for both energy and emissions trading. The thesis concludes that what counts as ‘unconventional’ is not given, but continues to be both created and contested at the same time as it is ‘conventionalized’.
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Beneficiation Of Himmetoglu And Beypazari Oil Shales By Flotation And Their Thermal Characterization As An Energy SourceAltun, Naci Emre 01 January 2006 (has links) (PDF)
Processing of Bolu-Himmetoglu (Type I Kerogen) and Ankara-Beypazari (Type II Kerogen) oil shales by flotation techniques were investigated for achieving clean solid fuel substitutes. Materials characterization was done through mineralogical, XRD and FTIR analyses. Flotation responses of the samples were tested with non-ionizing and ionizing collectors of cationic and anionic types. The effects of the collector dosage and pulp pH on cleaning were determined. Other important flotation parameters, conditioning time, flotation time, pulp density, particle size and frother dosage were encountered using a statistical approach, through a full two level factorial experimental design. An advanced flotation procedure, assisted by ultrasonic application, was developed for further improvement in flotation performance. The effects of cleaning on thermal characterstics and combustion kinetics were evaluated with Differential Scanning Calorimetry and ASTM methods while the changes in the emission profiles were assessed using Effluent Gas Analysis.
Himmetoglu sample was characterized as a carbonate and organic rich humic oil shale with XRD and FTIR analyses while Beypazari oil shale involved significant carbonate and clay minerals and exhibited a fulvic character with a poor organics content. Reverse flotation with amine acetates provided the most effective means of cleaning with Himmetoglu oil shale. Ash was decreased from 34.76 % to 23.52 % with a combustible recovery of 83.57 % using 800 g/ton Flotigam CA at natural pH and the calorific value increased from 4312 kcal/kg to 5010 kcal/kg. Direct flotation with amines was most effective for Beypazari oil shale cleaning. Using Armoflote 17, ash was reduced from 69.88 % to 53.10 % with 58.64 % combustible recovery using 800 g/ton Armoflote 17 at natural pulp pH and the calorific value of the sample increased from 876 kcal/kg to 2046 kcal/kg. Following optimization, ash of Himmetoglu oil shale decreased to 16.81 % with 84.10 % combustible recovery and calorific value increased to 5564 kcal/kg. For Beypazari oil shale ash decreased to % 48.42 with 59.17 % combustible recovery and the calorific value increased to 2364 kcal/kg. Ultrasonic pre-treatment before flotation further decreased the ash of Himmetoglu sample to 11.82 % with 82.66 % combustible recovery at 15 minutes pre-conditioning time and 50 % power level. For Beypazari oil shale, ash decreased to 34.76 % with 64.78 % combustible recovery after 15 minutes pre-treatment time at 70 % power level. Comparative XRD spectra and SEM analyses revealed that the extent of mineral matter removal relied on the flotation performance.
The thermal indicators considerably improved after cleaning and the extent of improvement increased with a decrease in the ash of the concentrates. Kinetic analysis showed the favorable effect of inorganics removal on the effectiveness and easiness of combustion and activation energies decreased after cleaning for both oil shales. The contributions of cleaning on the effectiveness of combustion were also revealed by the increases in the emission rates and total CO2 and CO emission amounts. CO2 emissions due to mineral matter decomposition and harmful SO2 emissions apparently decreased as a consequence of the cleaning of the undesired inorganic contituents and potentially cleaning components. Results of the cleaning and thermal analysis sudies revealed that it was possible to achieve a clean energy source alternative from oil shales through flotation and a significant potential can be anticipated for future use of oil shales as a cost effective and environmental friendly solid fuel substitute in view of Turkey& / #8217 / s great oil shale reserves.
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Environmental impact assessment on oil shale extraction in Central JordanGharaibeh, Ahmed 21 June 2017 (has links) (PDF)
This study focuses on the environmental impact assessment of trace elements concentrations in spent shale, which is the main residual besides gas and steam from the utilization of oil shale.
The study area El-Lajjun covers 28 km2, located in the centre of Jordan approximately 110 km south of Amman. It belongs mainly to the Wadi Mujib catchment and is considered to be one of the most important catchments in Jordan.
The Wadi El-Lajjun catchment area (370 km2) consists of two main aquifer systems: The intermediate aquifer (Amman Wadi As Sir Aquifer or B2/A7) and the deep sandstone aquifer (Kurnub/Ram Group Aquifer). The B2/A7 aquifer (Upper Cretaceous) is considered as the main source of fresh water in Jordan.
El-Lajjun oil shale was deposited in a sedimentary basin and comprises massive beds of brown-black, kerogen-rich, bituminous chalky marl. The oil shale was deposited in shallow marine environment. It is by definition a sedimentary rock containing organic material in the rock matrix. The shale oil extraction is an industrial process to decompose oil shale and to convert the kerogen into shale oil by hydrogenation, pyrolysis or by a thermal dissolution.
Several classifications of extraction technologies are known; the classification with respect to the location where the extraction takes place distinguishes between off-site, on-site, and in situ. The oil shale utilization may have serious repercussions on the surrounding environment if these issues are not investigated and evaluated carefully.
Ten representative oil shale rock samples with a total weight about 20 kg were collected from different localities of oil shale exposures in the study area. A standardized laboratory Fischer Assay test was performed with the samples to determine oil shale characteristics and to obtain spent shale, which was used in this study for further investigations. Sequential extraction was used to evaluate the changes in the mobility and distribution of the trace elements: Ti, V Cr, Co, Zn, As Zr, Cd, Pb and U. Column leaching experiments were performed to simulate the leaching behavior of the above elements from oil shale and spent shale to evaluate the possible influence on the groundwater in the study area. The concentrations in the leachate were below the maximum contaminant levels of the Environmental Protection Agency (EPA) for drinking water and the Jordanian standards for drinking water.
An immobilization method by using Kaolin was applied to reduce the mobilization and bioavailability of the trace elements fraction that are contained in the spent shale. Immobilization was evaluated as a function of liquid-solid ratio (solid-liquid partitioning) and as a function of pH. A comparison between the results obtained from column leaching experiments and the results that were obtained from immobilization for the oil shale and spent shale samples indicated that the immobilization reduced the mobility of the trace element except for Ti, V, and Cr. However, even the concentrations of these elements were lower than the maximum acceptable limits of the Jordanian Standard Specifications for waste water.
The catchment of the study area (Wadi El-Lajjun catchment) is ungauged. Therefore, the soil conservation service (SCS) runoff curve number method was used for predicting direct runoff from rainfall. The results obtained showed that the infiltration of water is very small (approximately 0.6 cm/year) and rarely can´t reach the groundwater through the oil shale beds. Thus, a contamination of groundwater is unlikely under normal conditions.
DRASTIC was used to assess groundwater vulnerability for the B2/A7 aquifer with respect to pollution by oil shale utilization. The aquifer vulnerability map shows that the area is divided into three zones: low (risk index 10-100; intermediate (risk index 101–140) and high groundwater vulnerability (risk index 141-200). The high risk areas are small and mainly located in the northeastern corner of the El-Lajjun graben, where the hydraulic conductivity is relatively high and rocks are highly fractured and faulted.
The water table of the deep sandstone aquifer (Kurnub/Ram group) in the El-Lajjun area is relatively deep. At least two geological formations above the Kurnub aquifer are aquitards and protect the deep aquifer. However, the area is highly fractured and thus there is a certain possibility for contact with surface pollutants.
Finally, further research with respect to trace elements including REE elements and isotopes in the intermediate and deep sandstone aquifers are highly recommended. Isotopic signatures will be very helpful to investigate to which extend hydraulic connections between the aquifers exist.
Further and in particular mineralogical studies on the spent shale and the possibilities for industrial utilization are recommended because huge quantities of spent shale are expected. Because most oil shale extraction technologies especially the power generation require considerable amounts of water detailed studies on water supply for the oil shale treatment have to be performed.
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Environmental impact assessment on oil shale extraction in Central JordanGharaibeh, Ahmed 06 December 2017 (has links)
This study focuses on the environmental impact assessment of trace elements concentrations in spent shale, which is the main residual besides gas and steam from the utilization of oil shale.
The study area El-Lajjun covers 28 km2, located in the centre of Jordan approximately 110 km south of Amman. It belongs mainly to the Wadi Mujib catchment and is considered to be one of the most important catchments in Jordan.
The Wadi El-Lajjun catchment area (370 km2) consists of two main aquifer systems: The intermediate aquifer (Amman Wadi As Sir Aquifer or B2/A7) and the deep sandstone aquifer (Kurnub/Ram Group Aquifer). The B2/A7 aquifer (Upper Cretaceous) is considered as the main source of fresh water in Jordan.
El-Lajjun oil shale was deposited in a sedimentary basin and comprises massive beds of brown-black, kerogen-rich, bituminous chalky marl. The oil shale was deposited in shallow marine environment. It is by definition a sedimentary rock containing organic material in the rock matrix. The shale oil extraction is an industrial process to decompose oil shale and to convert the kerogen into shale oil by hydrogenation, pyrolysis or by a thermal dissolution.
Several classifications of extraction technologies are known; the classification with respect to the location where the extraction takes place distinguishes between off-site, on-site, and in situ. The oil shale utilization may have serious repercussions on the surrounding environment if these issues are not investigated and evaluated carefully.
Ten representative oil shale rock samples with a total weight about 20 kg were collected from different localities of oil shale exposures in the study area. A standardized laboratory Fischer Assay test was performed with the samples to determine oil shale characteristics and to obtain spent shale, which was used in this study for further investigations. Sequential extraction was used to evaluate the changes in the mobility and distribution of the trace elements: Ti, V Cr, Co, Zn, As Zr, Cd, Pb and U. Column leaching experiments were performed to simulate the leaching behavior of the above elements from oil shale and spent shale to evaluate the possible influence on the groundwater in the study area. The concentrations in the leachate were below the maximum contaminant levels of the Environmental Protection Agency (EPA) for drinking water and the Jordanian standards for drinking water.
An immobilization method by using Kaolin was applied to reduce the mobilization and bioavailability of the trace elements fraction that are contained in the spent shale. Immobilization was evaluated as a function of liquid-solid ratio (solid-liquid partitioning) and as a function of pH. A comparison between the results obtained from column leaching experiments and the results that were obtained from immobilization for the oil shale and spent shale samples indicated that the immobilization reduced the mobility of the trace element except for Ti, V, and Cr. However, even the concentrations of these elements were lower than the maximum acceptable limits of the Jordanian Standard Specifications for waste water.
The catchment of the study area (Wadi El-Lajjun catchment) is ungauged. Therefore, the soil conservation service (SCS) runoff curve number method was used for predicting direct runoff from rainfall. The results obtained showed that the infiltration of water is very small (approximately 0.6 cm/year) and rarely can´t reach the groundwater through the oil shale beds. Thus, a contamination of groundwater is unlikely under normal conditions.
DRASTIC was used to assess groundwater vulnerability for the B2/A7 aquifer with respect to pollution by oil shale utilization. The aquifer vulnerability map shows that the area is divided into three zones: low (risk index 10-100; intermediate (risk index 101–140) and high groundwater vulnerability (risk index 141-200). The high risk areas are small and mainly located in the northeastern corner of the El-Lajjun graben, where the hydraulic conductivity is relatively high and rocks are highly fractured and faulted.
The water table of the deep sandstone aquifer (Kurnub/Ram group) in the El-Lajjun area is relatively deep. At least two geological formations above the Kurnub aquifer are aquitards and protect the deep aquifer. However, the area is highly fractured and thus there is a certain possibility for contact with surface pollutants.
Finally, further research with respect to trace elements including REE elements and isotopes in the intermediate and deep sandstone aquifers are highly recommended. Isotopic signatures will be very helpful to investigate to which extend hydraulic connections between the aquifers exist.
Further and in particular mineralogical studies on the spent shale and the possibilities for industrial utilization are recommended because huge quantities of spent shale are expected. Because most oil shale extraction technologies especially the power generation require considerable amounts of water detailed studies on water supply for the oil shale treatment have to be performed.
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Kurz- und langfristige Angebotskurven für Rohöl und die Konsequenzen für den MarktSchlothmann, Daniel 08 March 2016 (has links)
In dieser Arbeit wurden Angebotskurven für 22 bedeutende Ölförderländer ermittelt und anschließend zu globalen Angebotskurven aggregiert. Gemäß den ermittelten Angebotskurven sind nahezu alle gegenwärtig in der Förderphase befindlichen Ölprojekte in den Untersuchungsländern auch beim aktuellen Ölpreis von 35 bis 40 US-$ je Barrel unter Berücksichtigung der kurzfristigen Grenzkosten rentabel. Sollte der Ölpreis jedoch in den kommenden Jahren auf diesem Niveau verharren, wird es bis zum Jahr 2024 zu einem Angebotsengpass auf dem globalen Ölmarkt kommen, da zur Deckung der zukünftigen Nachfrage die Erschließung kostenintensiver, unkonventioneller Lagerstätten und von Lagerstätten in tiefen und sehr tiefen Gewässern notwendig ist. Damit es bis zum Jahr 2024 nicht zu einem solchen Angebotsengpass kommt, ist gemäß des ermittelten langfristigen Marktgleichgewichts ein Ölpreis von mindestens 80 (2014er) US-$ je Barrel notwendig.:1. Einleitung
2. Rohöl - Eine naturwissenschaftliche Einführung
3. Charakteristika von Rohölprojekten
4. Historie der Ölindustrie
5. Ökonomik von Rohölprojekten
6. Fallstudien zu den bedeutendsten Förderländern
7. Ermittlung regionaler und globaler Angebotskurven
8. Zusammenfassung
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Kurz- und langfristige Angebotskurven für Rohöl und die Konsequenzen für den MarktSchlothmann, Daniel 20 April 2016 (has links) (PDF)
In dieser Arbeit wurden Angebotskurven für 22 bedeutende Ölförderländer ermittelt und anschließend zu globalen Angebotskurven aggregiert. Gemäß den ermittelten Angebotskurven sind nahezu alle gegenwärtig in der Förderphase befindlichen Ölprojekte in den Untersuchungsländern auch beim aktuellen Ölpreis von 35 bis 40 US-$ je Barrel unter Berücksichtigung der kurzfristigen Grenzkosten rentabel. Sollte der Ölpreis jedoch in den kommenden Jahren auf diesem Niveau verharren, wird es bis zum Jahr 2024 zu einem Angebotsengpass auf dem globalen Ölmarkt kommen, da zur Deckung der zukünftigen Nachfrage die Erschließung kostenintensiver, unkonventioneller Lagerstätten und von Lagerstätten in tiefen und sehr tiefen Gewässern notwendig ist. Damit es bis zum Jahr 2024 nicht zu einem solchen Angebotsengpass kommt, ist gemäß des ermittelten langfristigen Marktgleichgewichts ein Ölpreis von mindestens 80 (2014er) US-$ je Barrel notwendig.
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