Orientador: Sueli Yoshinaga Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-20T15:45:24Z (GMT). No. of bitstreams: 1 SouzaFilho_MarioNascimento_M.pdf: 8976577 bytes, checksum: 06f17de0e0e20fb1daea5a785d88c120 (MD5) Previous issue date: 2012 / Resumo: Os recursos conhecidos de energia geotermal no Brasil são de baixa entalpia, com fontes contendo fluidos com valores de temperatura inferiores a 100ºC. Isto por si só desencoraja a tentativa de buscar cenários possíveis de aproveitamento das fontes, restritas até então, aos usos através de balneários, com o aproveitamento dos poços mais profundos perfurados inicialmente para petróleo, principalmente na Bacia do Paraná. Estudos recentes foram desenvolvidos em diversos países com vistas ao aproveitamento geotermal de bacias sedimentares, semelhantes às nossas, buscando recursos geotermais, abaixo do topo do embasamento, nos denominados HDR (Hot Dry Rock), através de injeção de fluidos que irão circular no meio rochoso fraturado (artificialmente ou não), aquecer e retornar à superfície em forma de vapor, para então serem aproveitados. Este cenário foi avaliado e estudado para um eventual aproveitamento na Bacia de Taubaté. Uma pesquisa bibliográfica foi feita focada no tema em estudo e não pretendeu esgotar o assunto, mas sim servir de ponto de partida para realizá-los. Foram tratados os perfis geofísicos de 39 poços selecionados no vale do Paraíba do Sul, entre Jacareí e Cachoeira Paulista, no Estado de São Paulo, identificadas as alternâncias litológicas, medidas as temperaturas dos poços, em construção, as espessuras dos distintos litotipos e traçados mapas de isovalores do topo do embasamento cristalino e sua temperatura. A partir desse ponto calculou-se o grau geotérmico para a área e foram traçados mapas previsionais de temperatura no horizonte 1.000 metros de profundidade sobrepostos aos mapas temáticos da distribuição percentual dos litotipos encontrados na bacia, com vistas ao aproveitamento econômico dos recursos geotermais. Duas áreas no vale do Paraíba despertaram interesse e será objeto de novas prospecções com vistas à definição do Projeto de Avaliação de Energia Geotermal na Bacia de Taubaté / Abstract: The known geothermal energy resources of Brazil have a low enthalpy level, with sources showing temperature levels lower than 100º Centigrade This fact by itself had discouraged initiatives aimed to find possible scenarios for utilization of such sources, which had been employed insofar for recreational activities in water resorts by means of exploitation of deep wells drilled initially for oil and gas in Paraná Basin. Recent studies were developed several countries aiming at geothermal utilization of sedimentary basins, similar to the Brazilian ones, searching for geothermal resources named Hot Dry Rock (HDR), through injection of fluids that will circulate within rocky fault or fractured crystalline basement and return to the surface in form of vapor in order to be utilized. This scenario is being evaluated and hereto studied for potential utilization in Taubaté Basin. Bibliographic research was made focused in this subject studied and it does not aim to exhaust this subject but rather support such studies and become a starting point. Geophysical logs of 39, mainly water wells drilled in Paraíba do Sul Valley, between Jacareí and Cachoeira Paulista, were analyzed and different lithological beds were interpreted. Temperatures of wells in construction were measured, the thickness of distinguished litologies and a surface trend analysis maps were constructed. The target of this study is the evaluation of the crystalline basement top and its temperature. Throughout this point the study aims to calculate the geothermic grade for the area and evaluate the region potentiality taking into consideration the economic exploitation of the geothermal resources. Two areas in Paraíba Valley have attracted interest and will be subject to new prospections aiming the definition of the Project for Evaluation of Taubaté Basin Geothermal Energy / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

Ph.D (Geology) / The Karoo succession has economic significance through the exploitation of extensive coal deposits and in recent years has seen significant international interest due to potentially large shale gas resources. The thermal history of sedimentary basins affects the genesis of hydrocarbon deposits and it is therefore essential to model and reconstruct the geothermal variation across the Karoo Basin before evaluation of the hydrocarbon resources can take place. The main scientific questions related to the thermal history of the Karoo Basin are whether the emplacement of large volumes of magma was preceded by a large-scale lowgrade thermal doming as proposed for continental rift settings. Alternatively, was the Karoo thermal event restricted to the contact aureole of intrusives, as well as the question whether the intrusion of dolerite resulted in large-scale CO2 or CH4 degassing from coalbeds and carbonaceous shales based on similarities to other large igneous provinces? Magnetic techniques provide an alternative to more traditional methods to study the geothermal history of sedimentary basins (such as illite crystallinity and vitrinite reflectance), which are often associated with significant uncertainty. Three experiments using existing magnetic and palaeomagnetic methods were conducted to determine the peak temperatures reached by Karoo sedimentary rocks before and after the Karoo magmatic event. These experiments include the classic palaeomagnetic baked contact tests (magnetostratigraphy), analyses of the variation of magnetic susceptibility during repeated progressive heating (alteration index method) as well the variation of relative concentrations of fine grained pyrrhotite and magnetite in sedimentary strata relative to their distance from an intrusive (pyrrhotite/magnetite geothermometer). Additionally various magnetic fabric analyses were performed including a study of the variation in anisotropy of magnetic susceptibility (AMS). Although these techniques were successful in delineating the extent of the contact aureoles, only the alternating index (A40) had the ability to give estimated peak temperatures. Results indicate a general elevation of palaeotemperatures of the organic-rich sedimentary rocks of the Ecca Group to temperatures where hydrocarbons are normally converted into gas. Importantly, it is clear from this study that the greatest thermal effects of the sill intrusions on the sedimentary strata are limited to the contact aureoles, suggesting that there is an, as yet unquantified, potential for hydrocarbon resources remaining between these intrusions. A general increase in the palaeotemperatures from southwest to northeast across the basin was observed. This is mainly due to differences in thermal conductivity of the various lithologies across the basin from tight low porosity marine shales in the south and southwest towards more lacustrine mudstone and porous sandstone in the northeast.

No description available.

South Africa generates more than 90 percent of its total energy capacity through non-renewable sources. With coal forming the predominant energy source, South Africa became the leading carbon emissive nation in Africa, emitting 450 million tonnes of CO2 in 2011. In an international effort to restrict global average temperature rise to 2° C above the average prior the industrial revolution, the Kyoto Protocol has been extended for another 8-year commitment period. This is complementary to an expected resolution of a new legally binding climate change policy in 2015. This policy will aim to introduce financial penalties for nations failing to meet ascribed GHG emission targets by 2020. In an attempt to meet these climate change resolutions South Africa will research and develop cleaner, alternative forms of energy, including hydro, wind, and biomass forms of renewable energy, in addition to designating stringent building regulations for the Incorporation of solar energy. These measures form part of an Integrated evelopment Plan that aims to generate a target of 10,000 GWh of renewable energy in 2013. South Africa is also investigating the possibilities of extracting its shale gas reserves and implementing it as a major energy source. This energy mix has given little attention to geothermal energy. The reasons for this omission appears to be the lack of active volcanism and previous research that suggests South Africa, largely underlain by the Kaapvaal Craton, has a relatively low heat Flow profile, deemed insufficient for harnessing geothermal energy.

Downhole sampling of unboiled liquid at 1350 and 1500 m depth in the seawater-dominated Reykjanes high-temperature geothermal system in Iceland shows that metal concentrations measured at surface are minimum values due to mineral precipitation in the wells; by analogy of similar tectonic setting, host rocks and fluid composition, the metal concentrations measured in many black smoker vents at the seafloor are also minima. Fluids in the Reykjanes geothermal system react with mid-ocean ridge basalt at temperatures as high as 346°C and contain Fe 9-140 ppm, Cu 14-17 ppm, Zn 5-27 ppm, Pb 120-290 ppb, 1-6 ppb Au, and 28-107 ppb Ag. Fluids discharged at surface from the same wells have orders of magnitude lower metal concentrations due to precipitation caused by boiling and vapor loss during depressurization. Upstream of the orifice plate at high pressure (40 bar, 252°C) the precipitates consist mainly of sphalerite and chalcopyrite with a trace of galena and bornite. At the orifice plate of old wells, the pressure decreased sharply to 11 bar (188°C), resulting in abundant deposition of amorphous silica together with minor sphalerite and traces of chalcopyrite. In new wells the pressure at the orifice plate decreases to 22 bar (220°C); this pressure decrease and concomitant boiling causes deposition of fine-grained bornite-digenite solid solution together with sphalerite and galena on the fluid flow control valve. In high-pressure wells (average wellhead pressure 45-35 bar) most metals (mainly as sphalerite) are deposited downstream of the orifice plate, with up to 950 ppm Au and 2.5 wt.% Ag. Bulk concentrations in the scales vary between 15-60 wt.% upstream and downstream of the orifice plate and diminish from there. Iron increases up well from 8 to ~20 wt.% and decreases downstream of the orifice plate from 6 to 2 wt.% at the separation station; Cu downhole is ~3 wt.% but increases to 25 wt.% on the fluid flow control valve and then decreases; Pb downhole 100s ppm but at the wellhead is ~3 wt.%, increasing to 15 wt.% at the fluid flow control valve, then decreasing sharply from there.

Growing populations are contributing to resource scarcity, making it ever more important for governments to address resource challenges in a holistic and integrated manner. Energy, water and food are examples of these critical resources, and the province of Alberta in Canada faces an interesting opportunity to tackle all three in tandem. Alberta struggles with food insecurity, with one in ten households affected on an annual basis. The province has the additional issue of an abating fossil fuel-based energy sector. Retrofitting oil and gas wells to harness geothermal heat is a possible initiative that encourages an energy transition and boasts lesser environmental impacts. Further, combining geothermal heat with agricultural greenhouse production and thermally driven water filtration systems has the potential to reduce food insecurity and water scarcity in the province. The system thus handles all three food, energy and water security at once. As such, this report compares the overall sustainability of a conventional, natural gas-burning greenhouse against a novel, geothermally-heated greenhouse featuring thermally driven water filtration (membrane distillation) technology. The area of study is constrained to the greenhouse-rich region in Alberta between Edmonton and Red Deer that also has a high accessibility to geothermal heat. The comparison is conducted through a multi-criteria analysis following economic, social and environmental objectives, and is analyzed using quantitative data, scientific literature and surveys. The results indicate that the novel greenhouse exhibits a higher score as compared to the conventional greenhouse, implying that it is the preferred option on economic, social and environmental bases. The results are in keeping with economic and technical feasibility reports, though they shed new light on the social and environmental aspects – which were under-studied in the province. The geothermally-heated greenhouse system with membrane distillation acts as a holistic solution that targets energy, water and food issues in tandem, while contributing to Canada’s Sustainable Development Goals. The novel greenhouse is an avenue of exploration and development by policy-makers, greenhouse operators and researchers interested in attaining sustainable agriculture in Alberta, Canada.

Global warming is expected to affect the arctic harsher than other regions of the globe. Many plant species will face conditions that contradict their adaptations in a warming climate. Changes in habitat can lead to drastic changes in biodiversity as well as exerting a strong selective pressure for plants to evolve and adapt quickly. Herbivore grazing in the arctic also affects plant ecosystems e.g. by lowering biodiversity and changing species composition and may influence their response to warming. The aim of this study was to examine whether grazing influences plants’ adaptation to rising temperatures. Geothermally warmed areas have been used as in situ proxy systems for effects of warming climates on ecosystems. Grændalur, a geothermally warmed valley in southwest Iceland, was used as a study site to explore the effects of warming and grazing on ecosystems. Three soil temperature gradient transects were established there and each transect has six fenced-off plots, at different soil temperatures (ambient +0, +1, +3, +5, +10 and +20°C), and paired plots outside the fence that were grazed by sheep. Species richness, evenness, Shannon-Wiener and Simpson’s diversity, species cover, and composition as well as plant height were measured in these plots inside and outside the fence. In addition, flowering and vegetative Ranunculus acris (meadow buttercup) individuals were counted in each plot to assess grazing effects on flowering success. Grazing did not influence the plant community response to warming. Rising temperature decreased species richness and both Shannon-Wiener and Simpson’s diversity, and drove changes in community composition. Plant height increased with rising temperatures but decreased with grazing. Grazing also significantly reduced R. acris flowering. These results highlight the need for sustainable grazing management in Iceland, as well as the significance global warming has for plant communities.

This master’s thesis analyses Kalina cycle, a power cycle where ammonia – water solution is used as a working fluid. The first part of this study introduces us to the Kalina cycle, presents its advantages and disadvantages, characteristics of the working fluid and its applications. Second section concerns with the method of cycle design and describes the calculation model made in this thesis. The calculation model is attached in a separate .XLSM file. The third part shows calculation of the cycle for given parameters, determination of cycle efficiency and main proportions of the thermal turbine. In the conclusion are the interpretations of the calculations results.

Im Freistaat Sachsen werden ca. 11.000 Gebäude mit Erdwärme klimatisiert. Genutzt wird die Wärme aus der Tiefe vor allem bei Ein- und Mehrfamilienhäusern zur Heizung und Warmwasserbereitung. Bei Planung und Bau von Erdwärmeanlagen sind Aspekte der Qualitätssicherung und rechtliche Vorgaben zu beachten. Interessierten Bürgern, Planern und Bohrfirmen werden u. a. folgende Fragen beantwortet: Welche Nutzungsformen der Erdwärme gibt es? Welche Qualitätsanforderungen, Richtlinien und Gesetze sind einzuhalten? Wie wird eine Anlage richtig geplant? Wo und wie werden Bohrungen bei Behörden beantragt?

Im Freistaat Sachsen werden 7.500 Gebäude mit Erdwärme klimatisiert. Genutzt wird die Wärme aus der Tiefe vor allem bei Ein- und Mehrfamilienhäusern zur Heizung und Warmwasserbereitung. Bei Planung und Bau von Erdwärmeanlagen sind Aspekte der Qualitätssicherung und rechtliche Vorgaben zu beachten. Interessierten Bürgern, Planern und Bohrfirmen werden u. a. folgende Fragen beantwortet: - Welche Nutzungsformen der Erdwärme gibt es? - Welche Qualitätsanforderungen, Richtlinien und Gesetze sind einzuhalten? - Wie wird eine Anlage richtig geplant? - Wo und wie werden Bohrungen bei Behörden beantragt? Die Informationsbroschüre erscheint in 3. Auflage und ersetzt den Leitfaden für Erdwärmesonden.