L’objectif de cette thèse est d’arriver à mieux contraindre les paramètres qui contrôlent les processus d’altération à l’échelle d’un petit bassin versant, en se focalisant plus précisément sur le rôle de l’hydrologie. Pour ce faire, les variations temporelles et spatiales des signatures chimiques et isotopiques (U, Sr) des eaux du bassin versant du Ringelbach (Vosges, France) sont étudiées. Plusieurs sources de ce bassin versant, essentiellement composé d’un granite plus ou moins fracturé, ont été échantillonnées mensuellement sur une période de deux ans, le long d’un profil altitudinal. Ce bassin versant présente également l’avantage d’être équipé de trois forages profonds (allant jusqu’à 150 mètres de profondeur) qui ont permis de prélever à la fois les roches et les eaux profondes. Sur la base de l’interprétation géochimique des eaux, la connectivité des différents compartiments hydrologiques a été évaluée et un schéma de fonctionnement hydrogéochimique est proposé s’appuyant sur une bonne connaissance du contexte géologique. Enfin, un taux d’altération et un flux d’eau sont estimés à partir d’une modélisation de l’évolution du rapport isotopique de l’uranium (234U/238U) le long d’un trajet d’eau. L’originalité de cette étude est également de coupler cette approche de traçage géochimique avec une approche modélisatrice en utilisant le logiciel KIRMAT (Kinetic Reactions and Mass transport) qui intègre les équations des réactions géochimiques (dissolution/précipitation) et les équations de transport (1D). Il est ainsi possible de simuler le transport réactif d’une eau traversant la roche le long d’un certain trajet d’eau. Cette modélisation s’appuie sur la caractérisation minéralogique, des propriétés physiques des échantillons de roches prélevés le long des forages et sur les interprétations géochimiques des eaux. Ainsi, la modélisation de la composition chimique des eaux de sources et des eaux de forages a permis d’affiner la compréhension des processus d’altération, notamment le rôle des phases secondaires précipitées. Celle-ci permet également une meilleure compréhension des phénomènes de couplage entre les différents paramètres qui contrôlent la signature chimique des eaux à l’échelle du bassin versant. / The main goal of the present thesis is to better constrain the parameters that control weathering processes at a small catchment scale, focusing specifically on the role of hydrology. For this purpose, temporal and spatial variations of the chemical and isotopic (U, Sr) water composition of the Ringelbach catchment are studied. Several springs of this catchment whose basement is mainly composed of granite more or less fractured located along an altitudinal profile were monthly sampled over a period of two years. The additional interest of this site is that three deep boreholes (up to 150 meters deep) allow the sampling of both deep rocks and waters. The connectivity of the different hydrological compartments is evaluated based on the geochemical interpretation of water samples. A schematic hydrological functioning is proposed based on a good knowledge of the geological context. Finally, a weathering rate and a water flux are estimated from the modeling of the uranium activity ratio along a water path. The originality of this study lays also in combination of a geochemical and modeling approaches using the software KIRMAT (Kinetic Reactions and Mass transport) that integrates geochemical reactions (dissolution/precipitation) and 1D mass transport equations. It allow to simulate the reactive transport of a fluid through a rock along a given water pathway. This modeling is based on the characterization of the mineralogical and physical properties of the rock, sampled along the boreholes and the geochemical interpretation of the waters. Thus, the modeling of the chemical composition of the spring waters and borehole waters permit to improve the understanding of weathering processes including the role of precipitated secondary phases. It also allows to better understand the interplay of parameters that that control the water chemical signature at the catchment scale.

Made available in DSpace on 2014-10-09T12:36:01Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:48Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:36:01Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:48Z (GMT). No. of bitstreams: 0 / Pasta de cimento é um material comum em repositórios para rejeitos radioativos, atuando como material estrutural e de imobilização. Sua utilização como material de preenchimento em um repositório tipo poço tubular profundo para fontes seladas, no entanto, requer um maior tempo de vida útil do material. O conhecimento de seu comportamento em longo prazo é necessário para garantir a segurança da instalação em milhares de anos. O presente trabalho avaliou as alterações na pasta de cimento induzidas por fatores de degradação, como ataque de agentes agressivos, alta temperatura e presença de campo de radiação. Corpos de prova (cps) de pasta de cimento foram submetidos a ensaios acelerados de degradação e os efeitos deletérios foram avaliados por meio de ensaios de resistência mecânica, variação dimensional, lixiviação/penetração de íons, DRX, TGA e MEV. Observou-se que a hidratação dos cps foi beneficiada pela imersão (em água destilada ou em solução salina) e alta temperatura, resultando em uma resistência maior. O armazenamento à seco prejudicou a hidratação, mantendo a resistência mais baixa. O tempo de imersão e a irradiação não foram capazes de alterar a mineralogia e a resistência da pasta de cimento. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

MESHWR / Department of Hydrology and Water Resources / See the attached abstract below

MESMEG / Department of Mining and Environmental Geology / This dissertation focused on the assessment of borehole yields within the Nzhelele- Makhado area, which is located in the northern part of South Africa within the Vhembe District Municipality of Limpopo Province. The aim of the study was to identify factors that influence the yields of water supply boreholes within the study area. This information will be used to improve the groundwater resource knowledge required in assessing the potential of groundwater resources in augmenting the Nzhelele Regional Water Supply Scheme. The study area is mostly underlain by the ‘hard rock’ formations of the Soutpansberg Group, which practically has no primary porosity. The groundwater is residing mainly within the weathered and fractured or discontinuities, considered being secondary porosities. Due to the complexity of the underlying fractured and hard rock aquifer systems and the fact that most of the boreholes drilled in the area were not scientifically sited, the study area is dominated by very low yielding boreholes. Majority (48%) of the boreholes were drilled into the Nzhelele formation due to the fact that it occupies the central, relatively flat and low lying sections of the study area. The variations in average yields in boreholes drilled in different formations within the study area is relatively low suggesting that the difference in lithology of different formations do not to have any major influence in the yields of boreholes. The topographical settings of the area do not have any influence in the borehole drilling depths and yields. The high borehole yields in shallow boreholes located in mountainous areas is due to local groundwater systems, which recharges and discharges locally. Mapped lineaments are slightly low yielding (average yield of 0.32 l/s) compared to the faults (average yield of 0.43 l/s) within the study area. Boreholes drilled along the NE-SW trending lineaments support double the yields (0.41 l/s) on average of those along the SE-NW (0.28 l/s) and W-E (0.20 l/s) trending lineaments. The high yields in boreholes closer to non-perennial streams compared to perennial rivers is due to the fact that non-perennial streams are comprised of thick layer of overburden capable of supporting high yielding boreholes, whereas the overburden along the perennial rivers are washed away during rainy season leaving bedrock exposed or covered with thin layer of sediments. The proximity to the young faults trending SE-NW and dry non-perennial streams has proved to be the most the favourable areas for development of high yielding boreholes in the study area, compared to lithological difference and topographical settings of the area. However, it should be noted that there are no simple relationship between various factors that control the yield of the boreholes in the area. Despite the similarities in some factors that influence borehole productivity on a regional scale such as faults and drainage systems, the complexity of the weathered-fractured aquifer system suggests an over-riding influence of local features, which results in significant variations in yield and response to abstraction. / NRF

Modern bottom-hole assemblies are equipped with various sensors which measure the geological and directional information of the borehole while drilling. It is very crucial to get the measured downhole information to the surface in real time in order to be able to monitor, steer and optimize the drilling process while drilling. The transmission of the information to the surface is most commonly carried out by coded pressure pulses (the technology called mud pulse telemetry) which propagate through the drilling mud inside the drill string towards the surface. However, hardly any specific experimental research on the hydraulic data transmission can be found in the literature. Moreover, it is essential to use a reliable model/simulation tool which can more accurately simulate the pressure pulse propagation in fluids inside drill strings under various drilling operation conditions in order to improve the performance of the data transmission process. The aims of this study are to develop and test a laboratory experimental setup, a simulation model and a novel method for detecting and decoding of measurement while drilling pressure pulse propagation in fluids inside drill strings. This thesis presents a laboratory experimental setup for investigating the process of data transmission in boreholes by mud pulse telemetry. The test facility includes a flow loop, a centrifugal pump, a positive mud pulser or alternatively a mud siren, pressure transducers at four different locations along the flow loop and a data collection system. Moreover, it includes an “actuator system” for the simulation of typical noise patterns created by the common duplex or triplex mud pumps. This laboratory setup with great capabilities opens the way for testing and developing new concepts for data transmission. A theoretical model using ANSYS CFX11 (Computational Fluid Dynamics (CFD) commercial code) was successfully developed to simulate dynamic pressure pulse transmission behavior in the fluid inside the flow loop. The collected laboratory data which simulate various data transmission processes in boreholes were used to verify and calibrate the theoretical method. A pretty good agreement is achieved between the predicted and measured pressure pulses at different locations along the flow loop for positive pulses with various durations using different flow rates and for continuous pressure pulses using different carrier frequencies. A novel approach (continuous wavelet transformation) for detecting and decoding the received continuous pressure pulses in a noisy environment was applied to various simulated drilling operation conditions for data transmission in boreholes in the laboratory. The concept was registered at the German Patent and Trade Mark Office (DPMA) for a patent in 2011. The results indicate that the continuous wavelet transformation can be used to clearly identify and better detect the continuous pressure pulse periods, frequencies and discontinuity positions in the time domain compared to the conventional method (Fourier transformation). This method will contribute to the possibility of transmitting the data at higher rates and over longer distances. A concept for developing an innovative pulser using electrical discharge or acoustic sources for inducing pulses keeping the drill strings fully open (eliminating the problem of plugging the pulser by pumped lost circulation materials) and without any mechanical moving parts (eliminating the failure related to the pulser moving parts) was also registered at the German Patent and Trade Mark Office (DPMA) for a patent in 2012. With this pulser, it is expected that it would be possible to transmit the data over longer distances and at higher rates. Realizing the concept of the new pulser and using continuous wavelet transformation for detecting and decoding the pulser signal are recommended for future work.

Sverige har en hög andel installerade bergvärmepumpar, som är en typ av vätska-vatten värmepump. Ett problem som finns för befintliga bergvärmesystem är att berget med tiden kyls ned då returslangen till borrhålet konstant levererar kyla till berget. Till följd av detta mister systemet en betydande del av sin verkningsgrad samtidigt som det i extrema fall kan leda till permanent isbildning i borrhålet. Ett sätt att motverka detta problem är att tillämpa termisk energilagring i bergvärmesystemets borrhål. Den internationella benämningen för denna teknik är ”Borehole Thermal Energy Storage, BTES”. Rapporten har behandlat en friliggande enplansvilla med ett befintligt bergvärmesystem som tillämpar termisk energilagring i bergvärmesystemets borrhål med solvärme. Två beräkningsfall har gjorts och resultatet från simuleringarna i en upprättad beräkningsmodell visar att en temperaturhöjning i borrhålet inte alltid innebär en årlig energibesparing. Vid varje grads temperaturhöjning sker en ökning av värmepumpens COP med ca 1,85 % enligt ett linjärt samband för höga temperaturdifferenser över värmepumpen. Detta motsvarar en kostnadsbesparing på 1,02 %/°C. Detta gäller för normala förhållanden med en framledningstemperatur för tappvarmvatten och rumsvärmare på 55 ⁰C. Med en högre energiförbrukning finns alltså större besparingar att göra. Vid mycket låga temperaturdifferenser mellan förångare och kondensor sker dock större procentuella förändringar, vilket medför att lågtemperatursystem kan bidra till en större energibesparing. I normalfallet är dessa system svåra att räkna hem för småhus. För en god lönsamhet krävs en optimerad systemlösning och effektiv styrning av cirkulationspumpar och andra samspelande komponenter med en PLC. I framtiden kommer dock sannolikt värmepumparnas mekaniska verkningsgrad att öka med bättre teknik och även energipriset som följd av politiska beslut, tillgång etc. Detta innebär att varje besparad kilowattimme kommer att bli mer värd. / Sweden has a high proportion of installed geothermal heat pumps, which are a type of liquid -water heat pump. One problem that exists for existing geothermal heating systems is that the rock in time cool down when the return hose to the borehole constantly supply cooling to the rock. As a result of this the system loses a significant portion of their efficiency while in extreme cases has led to the permanent ice in the borehole. One way to counter this problem is to apply thermal energy storage in the geothermal heating systems borehole. The international term for this technique is "Borehole Thermal Energy Storage, BTES". This report has analyzed a detached single storey house with an existing geothermal heating system utilizing thermal energy storage in the geothermal heating systems borehole with solar heating. Two calculation cases has been made and the results of the simulations in an established computational model shows that an increase in temperature in the borehole does not always result in an annual energy savings. Each degree of increased temperature is an increase in the heat pumps COP of 1.85 %, according to a linear relationship for high temperature differences across the heat pump. This results in a cost saving of 1.02 %/°C. This applies to normal conditions with a radiator temperature at 55 ⁰ C. With higher energy consumption can greater savings be made. At very low temperature differences between the evaporator and condenser is however larger percentage changes made, which means that low temperature systems can lead to greater energy savings. Typically, these systems are difficult to recoup for small detached houses. For a good profitability requires an optimized system solution and efficient control of circulation pumps and other interacting components with a PLC. In the future the heat pump mechanical efficiency will probably increase with better technology and even energy prices as a result of political decisions, access, etc. This means that each spared kilowatt hour will be worth more.

The choice of heating system in new residential buildings has a significant effect onthe total life cycle-cost. Rising energy prices and tougher energy demands for newbuildings creates incentive for energy- and cost-efficient solutions. The purpose ofthis project is therefore to investigate how the choice and sizing of a heating systemin a building can be performed with focus on cost-efficiency. The project is conducted as a case study on a residential building during the buildingphase on behalf of INTEC Dalarna AB, a technical engineering company. The project aim is to answer the following questions: – What heating system of district heating, ground source heat pumps or air towater heat pumps is the most cost-effective for a new residential building inthe middle of Sweden? – Is there a specific combination of a heat pump of arbitrary size and peak heating system that is particularly advantageous for the building? – Is IDA ICE suitable for simulation of energy use in buildings with heatpumps? – Does high energy-efficiency also mean high cost-efficiency for the building? The questions will be answered with building simulation software IDA Indoor Climate and Energy along with capital budgeting. The capital budgeting will be performed with net present value and payoff period for the heat pumps over choosingdistrict heating. The results of the project show that a system with ground source heat pumps with acapacity of 50 percent of the annual peak heat demand and electricity for peak loadsis the most cost-efficient option for the building. However, the most energy efficient option is a ground source heat pump with a capacity of 50 percent of the annual peak heat demand with district heating for peak loads. The project also shows that IDA ICE is suitable for simulating the performance of heat pumps in buildings.The conclusion is that a smaller system of ground source is more cost-efficient forthe building, and that the most energy efficient option is not always equal to themost cost-efficient over time.

Development of homes, roads, and commercial buildings in northern Utah has grown significantly during the last several decades. Construction has expanded from the valley floor to higher elevations of benches, foothills, and other elevated regions of the Wasatch Mountain Front. Construction in the higher elevation areas are a concern due to potential for landslides, both new and reactivated. Landslides have been identified in this region and are dated as Pleistocene to historical in age. A possible landslide of about 0.5 km2 on the south slope of Traverse Mountain has been mapped by the Utah Geological Survey in 2005. Its surface exhibits hummocky topography and is comprised of Oligocene-age volcanic ash, block and ash flow tuffs, and andesite lava. Landslides along the Wasatch Mountain Front are complex features usually characterized by dense vegetation and poor outcrop and require a combination geological and geophysical methods to study their thickness, slope, lateral extent, and style of emplacement. Our study incorporates trenching, boreholes, and LiDAR aerial imagery. Unique to the study of landslides is our use of seismic reflection with a vibroseis source over the mapped landslide deposit. The seismic parameters of source, station spacing, and processing method provide a coherent, albeit low-resolution, image of the upper 500 m of the subsurface beneath the landslide. A major reflector boundary in our seismic profiles has an apparent dip of 4° to the south, approximately parallel with the surface topography. Its elevation and seismic character are indicative of a contact between the Oligocene-age volcanic rocks on top of a portion of the Pennsylvanian-age Bingham Mine Formation, a mixed carbonate and siliciclastic sequence. The reflector defines an asymmetric graben-like structure bounded by a north-northwest-trending normal fault system. Analysis of trenches, boreholes and local geology reveals a faulted, chaotic body of block and ash flow tuffs, surrounded by andesite lavas. Using LiDAR and surface geological reconnaissance, a possible toe or margin of a landslide has been interpreted in the north-west portion of the study area. The combination weakened block and ash flow tuffs and abundant clay production from this unit contribute to the likelihood of a coalescence of landslides in this mapped landslide area. The integration of LiDAR, trenching, boreholes and reflection seismology provides the range and resolution of data needed to assess the complex geology of landslides.

Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2018-01-31T16:42:14Z No. of bitstreams: 0 / Made available in DSpace on 2018-01-31T16:42:14Z (GMT). No. of bitstreams: 0 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A deposição de rejeitos radioativos em repositórios geológicos profundos vem sendo estudada nos últimos anos em diversos países. Materiais à base de cimento são utilizados nesses repositórios como material estrutural, matriz de imobilização de rejeitos ou material de preenchimento. Compreender o desempenho desse material é essencial para garantir a segurança da instalação durante o seu tempo de vida útil (de milhares a centenas de milhares de anos, dependendo do tipo de rejeito). Este trabalho objetiva modelar o comportamento em longo prazo do cimento Portland e estudar a influência de diversos fatores na hidratação e na evolução desse material. A modelagem descritiva abordou a hidratação do cimento nas condições ambientais esperadas no repositório e os efeitos desses fatores em propriedades mecânicas, mineralógicas e morfológicas do cimento. Os fatores ambientais considerados relevantes neste trabalho foram: alta temperatura e pressão, penetração de água subterrânea contendo íons quimicamente agressivos ao cimento e a presença do campo de radiação proveniente dos rejeitos. Ensaios acelerados de degradação também foram realizados para corroborar com o modelo descrito. Observou-se uma sinergia entre diversos fatores na degradação do cimento, como a influência da temperatura e da radiação em reações deletérias ao material. O resultado da modelagem apontou três principais possíveis causas de falha nas barreiras artificiais: a) a formação de um caminho preferencial; b) a perda de resistência e coesão do material; e c) o aumento na corrosão das estruturas metálicas. A descrição do modelo apresentada é a base para a modelagem matemática e a análise de segurança dos repositórios estudados no Brasil. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP / CAPES:1231206