49 research outputs found
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CO2 storage, monitoring, verification, and accounting
Bureau of Economic Geolog
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Modeling CO2 Partitioning at a Carbonate CO2-EOR Site: Permian Basin Field SACROC Unit
Bureau of Economic Geolog
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Leveraging Geologic CO2 Storage Technology for CO2-EOR Management
Enhanced oil recovery (EOR) through CO2 injection has evolved from the laboratory testing and field piloting phases in the early 1970s to the widespread and refined operations of today. Over the last 20 years, geological CO2 storage (GCS) has emerged as a promising approach to dispose of large volumes of CO2. Much of the early advances in the operational aspects of GCS were learned from CO2-EOR. However, given its ĂąâŹĆnewnessĂąâŹïżœ and the health, safety, and environment (HSE) concerns related to CO2 emissions, considerable fundamental and applied research with heavily instrumented GCS field projects, from pilot to commercial scale, has produced data not ordinarily available from conventional CO2-EOR studies. A key exception is the Weyburn-Midale CO2-EOR project in Saskatchewan, Canada, which has had a dedicated characterization, reservoir dynamics and surveillance program in operation since 2000. Even though many of the processes and workflows for these two operations are similar, significant differences do exist primarily because of the different objectives and regulatory environments that exist for CO2-EOR and CO2 storage projects. Fundamentally, CO2 storage tools and processes are geared toward developing a much more detailed understanding of the storage system and the physical and chemical processes accompanying CO2 injection, with monitoring and surveillance being conducted during the pre-operational, operational, and post-operational stages of a project. Pre-operational monitoring for a CO2-EOR project is primarily focused on understanding the reservoir physical and petrophysical properties as well as the properties of the reservoir and injected fluids. Surveillance in the operational phase of an EOR flood is limited, with emphasis being placed on monitoring injection pressures and rates as well as the volumes and properties of the injected and produced fluids. Lessons learned from GCS research and field tests will likely benefit CO2-EOR project performance by employing aspects of characterization, simulation and surveillance. This study reviews the predictive and diagnostic tools currently applied to GCS projects and infers how their deployment might improve CO2-EOR projects. These improvements might include project conformance, CO2 utilization / oil produced, field management, and containment risks.Bureau of Economic Geolog
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Assessment of Geological Storage Capacity of the Southeastern U.S. for CO2 in Brines and Economic Use for EOR
Bureau of Economic Geolog
Robust estimation of bacterial cell count from optical density
Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data
COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study
Background:
The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms.
Methods:
International, prospective observational study of 60â109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms.
Results:
âTypicalâ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (â€â18 years: 69, 48, 23; 85%), older adults (â„â70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each Pâ<â0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country.
Interpretation:
This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men
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Carbon dioxide enhanced oil recovery potential and sequestration capacity in the Gulf Coast : a COâ sink analysis near Texas City
The Permian Basin in West Texas has seen a long history of COâ enhanced oil recovery (EOR). Over 65 sandstone, limestone, and dolomite reservoirs have been subject to miscible COâ floodings in the last 30 years. However, the experience gained has not been extended to the much more porous and permeable clastic depositional systems of the Gulf of Mexico. Proximity to possible anthropogenic COâ sources, enabling reduced costs and infrastructure, and the petrophysical character of these sandstones are just two of the many attributes that showcase the Gulf Coast formations as an attractive option for this type of tertiary recovery. Results of this assessment indicate that mature Gulf Coast clastic oil reservoirs are a new large potential target for COâ enhanced oil recovery when experience in the Permian Basin is retooled for this setting.Energy and Earth Resource
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EOR Potential from CO2 Captured from Coal-Fired Power Plants in the Upper Cretaceous (Cenomanian) Woodbine Group, East Texas Basin, and Southeastern Texas Gulf Coast, USA
Bureau of Economic Geolog
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Potential of CO2-EOR for Near-Term Decarbonization
Bureau of Economic Geolog
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Introduction to this special section: CO2 in the subsurface
Bureau of Economic Geolog