34 research outputs found

    Best Practices for Shale Core Handling: Transportation, Sampling and Storage for Conduction of Analyses

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    Drill core shale samples are critical for palaeoenvironmental studies and potential hydrocarbon reservoirs. They need to be preserved carefully to maximise their retention of reservoir condition properties. However, they are susceptible to alteration due to cooling and depressurisation during retrieval to the surface, resulting in volume expansion and formation of desiccation and micro fractures. This leads to inconsistent measurements of different critical attributes, such as porosity and permeability. Best practices for core handling start during retrieval while extracting from the barrel, followed by correct procedures for transportation and storage. Appropriate preservation measures should be adopted depending on the objectives of the scientific investigation and core coherency, with respect to consolidation and weathering. It is particularly desirable to maintain a constant temperature of 1 to 4 °C and a consistent relative humidity of >75% to minimise any micro fracturing and internal moisture movement in the core. While core re-sampling, it should be ensured that there is no further core compaction, especially while using a hand corer

    An improved understanding about CO2 EOR and CO2 storage in liquid-rich shale reservoirs

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    During the past decade, enhanced oil recovery (EOR) by CO2 in shale oils has received substantial attention. In shale oil reservoirs, CO2 diffusion into the resident oil has been considered as the dominant interaction between the CO2 in fractures and the oil in the matrices. CO2 diffusion will lead to oil swelling and improvement in oil viscosity. However, despite two-way mass transfer during CO2 EOR in conventional oil reservoirs, one-way mass transfer into shale oils saturated with live oils is controlled by an additional transport mechanism, which is the liberation of light oil components in the form of a gaseous new-phase. This in-situ gas formation could generate considerable swelling, which could improve the oil recovery significantly. This mechanism has been largely overlooked in the past. This study is aimed to better understand the role of this evolving gas phase in improving hydrocarbon recovery. Taking account of Bakken shale oil reservoir data, numerical simulations were performed to identify efficiencies of EOR by CO2 at the laboratory and field scales. Equation of state parameters between CO2 and oil components were adjusted to optimize the calculations and a sensitivity analysis was performed to identify the role of gas formation and consequent EOR efficiencies. At the laboratory scale, in-situ gas formation can increase oil recovery by 20% depending on the amount of gas saturation. Also, the CO2 storage capacity of the shale matrix can be enhanced by 25%, due to CO2 trapping in the gas phase. At the field scale, an additional oil recovery of 9.1% could be attained, which is notably higher than previous studies where this gas evolution mechanism was ignored. Furthermore, the results suggest that a six-weeks huff period would be sufficient to achieve substantial EOR if this new mechanism is incorporated. On the other hand, the produced fluid in the early period was primarily composed of CO2, which would make it available for subsequent cycles. The produced gas of the well under CO2 EOR was used in an adjacent well, which resulted in similar additional oil recovery and hence, impurities in CO2 injection stream would not undermine efficiency of this EOR method. The results of this study, therefore, could potentially be used to substantially improve the evaluations of CO2 EOR in liquid-rich shale reservoirs

    Direct gas-in-place measurements prove much higher production potential than expected for shale formations

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    Shale gas exploitation has been the game-changer in energy development of the past decade. However, the existing methods of estimating gas in place in deep formations suffer from large uncertainties. Here, we demonstrate, by using novel high-pressure experimental techniques, that the gas in place within deep shale gas reservoirs can be up to five times higher than that estimated by implementing industry standard approaches. We show that the error between our laboratory approach and the standard desorption test is higher for gases with heavier compositions, which are of strongest commercial interests. The proposed instrumentation is reliable for deep formations and, provides quick assessment of the potential for the gas in place, which could be useful for assessing hydrocarbon reservoirs, and the potential for geological carbon sequestration of a given formation

    A Fundamental Micro Scale Study of the Roles of Associated Gas Content and Different Classes of Hydrocarbons on the Dominant Oil Recovery Mechanism by CWI

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    Various studies demonstrated new gaseous phase formation and oil swelling and viscosity reduction are the oil recovery mechanisms by carbonated water injection (CWI) with new gaseous phase formation being the major recovery mechanism for live oil systems. However, none of the previous studies investigated the influences of dissolved gas content of the oil and oil composition, on the new gaseous phase. This study attempts to provide insights on this area. Based on the results, during CWI as CO2 partitions into the oil the dissolved gas of the oil liberates, which leads to in-situ new gaseous phase formation. The dissolved gas content of the crude oil has a direct impact on the saturation and growth rate of the new gaseous phase. The new gaseous phase doesn't form for oils that have an infinite capacity for dissolving CO2, such as light pure hydrocarbon components. Oils with limited capacity for dissolving CO2, such as heavy hydrocarbon components, are responsible for the formation of the new gaseous phase. Therefore for a live crude oil, the relatively heavier fractions of oil are responsible for triggering of the new gaseous phase and light to intermediate oil components control the further growth of the new gaseous phase

    A collective effort to identify and quantify geo-energy risks

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    The increasing global demand for energy and the imminent need to reduce carbon emissions in our planet has led mankind to find new solutions. Some in the energy industry have taken special interest in geothermal reservoirs, a resource with the potential to provide large amounts of renewable energy. Meanwhile, the storage of carbon dioxide in underground geological formations presents a fantastic opportunity to discard CO2 and mitigate global warming. This study links efforts from academic institutions, industry energy operators, industrial partners and research institutes to answer fundamental scientific questions that can help us understand the subsurface and generate better exploitation practices. We examine the geology of reservoirs used for geothermal energy extraction and carbon dioxide capture. We use a combination of field geology, photogrammetry, mineral analysis and experimental rock mechanics to understand fracture networks and fluid flow paths of two geologically diverse reservoirs in Europe: 1) the Hengill geothermal system in south-west Iceland, and 2) the Carnmenellis granite geothermal system in Cornwall (UK). These results aim to provide experimental data to refine numerical models predicting fluid flow and contribute to the quantification of the associated risks of exploiting the subsurface

    Mars 2020 Entry, Descent and Landing Instrumentation 2 (MEDLI2)

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    The Mars Entry Descent and Landing Instrumentation 2 (MEDLI2) sensor suite will measure aerodynamic, aerothermodynamic, and TPS performance during the atmospheric entry, descent, and landing phases of the Mars 2020 mission. The key objectives are to reduce design margin and prediction uncertainties for the aerothermal environments and aerodynamic database. For MEDLI2, the sensors are installed on both the heatshield and backshell, and include 7 pressure transducers, 17 thermal plugs, and 3 heat flux sensors (including a radiometer). These sensors will expand the set of measurements collected by the highly successful MEDLI suite, collecting supersonic pressure measurements on the forebody, a pressure measurement on the aftbody, direct heat flux measurements on the aftbody, a radiative heating measurement on the aftbody, and multiple near-surface thermal measurements on the thermal protection system (TPS) materials on both the forebody and aftbody. To meet the science objectives, supersonic pressure transducers and heat flux sensors are currently being developed and their qualification and calibration plans are presented. Finally, the reconstruction targets for data accuracy are presented, along with the planned methodologies for achieving the targets

    Heatshield for Extreme Entry Environment Technology (HEEET) Enabling Missions Beyond Heritage Carbon Phenolic

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    Future NASA robotic missions utilizing an entry system into Venus and the outer planets, results in extremely high entry conditions that exceed the capabilities of state of the art low to mid density ablators such as PICA or AVCOAT. Previously, mission planners had to assume the use of fully dense carbon phenolic heatshields similar to what was flown on Pioneer Venus or Galileo. Carbon phenolic is a robust TPS material, however, its high density and relatively high thermal conductivity constrain mission planners to steep entries, with high heat fluxes and pressures and short entry durations. The high entry conditions pose challenges for certification in existing ground based test facilities and the longer-term sustainability of CP will continue to pose challenges. NASA has decided to invest in new technology development rather than invest in reviving carbon phenolic. The HEEET project, funded by STMD is maturing a game changing Woven Thermal Protection System technology. HEEET is a capability development project and is not tied to a single mission or destination, therefore, it is challenging to complete ground testing needed to demonstrate a capability that is much broader than any single mission or destination would require. This presentation will status HEEET progress. Near term infusion target for HEEET is the upcoming New Frontiers (NF-4) class of competitively selected Science Mission Directorate (SMD) missions for which it is incentivized

    Heatshield for Extreme Entry Environment Technology (HEEET) Enabling Missions Beyond Heritage Carbon Phenolic

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    This poster provides an overview of the requirements, design, development and testing of the 3D Woven TPS being developed under NASAs Heatshield for Extreme Entry Environment Technology (HEEET) project. Under this current program, NASA is working to develop a Thermal Protection System (TPS) capable of surviving entry into Venus or Saturn. A primary goal of the project is to build and test an Engineering Test Unit (ETU) to establish a Technical Readiness Level (TRL) of 6 for this technology by 2017

    Heatshield for Extreme Entry Environment Technology (HEEET) TPS for Ice Giants Probe Missions

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    This poster provides an overview of the requirements, design, development and testing of the 3D Woven TPS being developed under NASAs Heatshield for Extreme Entry Environment Technology (HEEET) project. Under this current program, NASA is working to develop a Thermal Protection System (TPS) capable of surviving entry into Saturn. A primary goal of the project is to build and test an Engineering Test Unit (ETU) to establish a Technical Readiness Level (TRL) of 6 for this technology by 2018. Poster also discusses use of HEEET TPS for probe missions to the Ice Giants, Uranus and Neptune
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