The impact of supercritical CO2 on the pore structure and storage capacity of shales

The pore structure of marine-continental transitional shales from the Longtan Formation in Guizhou, China, was investigated using fractal dimensions calculated by the FHH (Frenkel-Halsey-Hill) model based on low-temperature N2 adsorption data. Results show that the overall D 1 (fractal dimension under low relative pressure, P / P 0 ≤ 0.5 ) and D 2 (fractal dimension under high relative pressure, P / P 0 > 0.5 ) values of Longtan shales were relatively large, with average values of 2.7426 and 2.7838, respectively, indicating a strong adsorption and storage capacity and complex pore structure. The correlation analysis of fractal dimensions with specific surface area, average pore size, and maximum gas absorption volume indicates that D 1 can comprehensively characterize the adsorption and storage capacity of shales, while D 2 can effectively characterize the pore structure complexity. Further correlation among pore fractal dimension, shale organic geochemical parameters, and mineral composition parameters shows that there is a significant positive correlation between fractal dimensions and organic matter abundance as well as a complex correlation between fractal dimension and organic matter maturity. Fractal dimensions increase with an increase in clay mineral content and pyrite content but decrease with an increase in quartz content. Considering the actual geological evaluation and shale gas exploitation characteristics, a lower limit for D 1 and upper limit for D 2 should be set as evaluation criteria for favorable reservoirs. Combined with the shale gas-bearing property test results of Longtan shales in Guizhou, the favorable reservoir evaluation criteria are set as D 1 ≥ 2.60 and D 2 ≤ 2.85 . When D 1 is less than 2.60, the storage capacity of the shales is insufficient. When D 2 is greater than 2.85, the shale pore structure is too complicated, resulting in poor permeability and difficult exploitation.

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Impact of Plant Siting on Performance and Economics of Indirect Supercritical CO2 Coal Fired Power Plants

10.1115/gt2021-58867 ◽

2021 ◽

Author(s):

Sandeep R. Pidaparti ◽

Charles W. White ◽

Nathan T. Weiland

Keyword(s):

Supercritical Co2 ◽

Optimization Design ◽

Power Plants ◽

Waste Heat ◽

The United States ◽

Attractive Alternative ◽

Plant Design ◽

Power Cycles ◽

The Impact ◽

And Storage

Abstract Indirect-fired supercritical CO2 (sCO2) power cycles are being explored as an attractive alternative to steam Rankine cycles for a variety of heat sources including fossil, concentrated solar power (CSP), nuclear, waste heat, etc. Due to the near-ambient CO2 critical temperature of 31°C, the effects of ambient temperature on sCO2 power cycles performance are expected to be more significant than for steam Rankine cycles. This study presents the impact of plant siting on the performance and economics of coal-fired utility scale power plants based on indirect sCO2 power cycles with carbon capture and storage (CCS). Four different plant sites across the United States have been selected for investigation: Chicago, IL; Kemmerer, WY; Houston, TX; Knoxville, TN. For each plant site, local parameters such as design ambient conditions, coal type and prices, captured CO2 transportation and storage (T&S) costs are considered for the techno-economic analyses (TEA). To determine the optimum plant design for each location, two power cycle configurations (recompression cycle, partial cooling cycle with reheat) and two cooling technologies (dry and adiabatic cooling) are examined. The optimization was conducted using automated derivative-free optimization (DFO) algorithms available under NETL’s Framework for Optimization and Quantification of Uncertainty and Sensitivity (FOQUS) platform. The optimization design variables include parameters such as turbine inlet temperatures and pressure, sCO2 cooler outlet temperatures, recuperators approach temperature and pressure drop etc. The study demonstrates the variability in optimal plant design for different ambient and fuel input conditions. The results will be used in future sCO2 technology market analyses.

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State of Indoor Experiments on Supercritical CO2-Brine Displacement System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.1208 ◽

2013 ◽

Vol 864-867 ◽

pp. 1208-1212

Author(s):

Zhen Zhang ◽

Yuan Wang ◽

Yang Liu

Keyword(s):

Supercritical Co2 ◽

Impact Factors ◽

Saline Aquifers ◽

Proper Understanding ◽

Multi Phase Flow ◽

Displacement System ◽

Multi Phase ◽

Future Work ◽

The Impact ◽

And Storage

As an emerging technique, carbon dioxide capture and storage (CCS) is to mitigate greenhouse gas emissions. Deep saline aquifers are increasingly considered because of their wide distributionlarge thicknesslarge capacity. A proper understanding of displacement character of supercritical CO2-brine system is significant in knowing CO2 Injectivity, migration and trapping, and in assessing the safety and suitability of reservoir site. CO2-brine system is multi-phase flow system, the mobility is related to interfacial tensioncapillary pressurerelative permeability. The experiments took into account the impact factors such as interfacial tensioncapillary pressurerelative permeability, foreign indoor experiments of CO2-brine system are analyzed and summarized, a brief description of indoor experiments of our country and future work are given.

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Energetic Comparison of Linear Fresnel and Parabolic Trough Collector Systems

ASME 2012 6th International Conference on Energy Sustainability, Parts A and B ◽

10.1115/es2012-91109 ◽

2012 ◽

Cited By ~ 7

Author(s):

Heiko Schenk ◽

Tobias Hirsch ◽

Jan Fabian Feldhoff ◽

Michael Wittmann

Keyword(s):

Storage Capacity ◽

Field Size ◽

Parabolic Trough ◽

Solar Salt ◽

Parabolic Trough Collector ◽

Power Block ◽

Thermodynamic Performance ◽

Solar Field ◽

The Impact ◽

And Storage

Within the last years, Linear Fresnel (LF) collector systems have been developed as a technical alternative to parabolic trough collector (PT) systems. In the past, LF systems focused on low- and medium temperature applications. Nowadays, LF systems equipped with vacuum receivers can be operated at the same temperatures as PT systems. Papers about the technical and economical comparison of specific PT and LF systems have already been published, [1–3]. However, the present paper focuses on the systematic differences in optical and thermodynamic performance and the impact on the economic figures. In a first step the optical performance of typical PT and LF solar fields has been examined, showing the differences during the course of the day and annually. Furthermore, the thermodynamic performance, depending on the operating temperature, has been compared. In a second step, the annual electricity yield of typical PT and LF plants are examined. Solar Salt has been chosen as heat transfer fluid. Both systems utilize the same power block and storage type. Solar field size, storage capacity, and power block electrical power are variable, while all examined configurations achieve the same annual electricity yield. As expected for molten salt systems, both systems are the most cost-effective with large storage capacities. The lower thermodynamic performance of the LF system requires a larger solar field and lower specific costs in order to be competitive. Assuming specific PT field costs of 300 €/m2 aperture, the break-even costs of the LF system with Solar Salt range between 202 and 235 €/m2, depending on the site and storage capacity.

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Energetic Comparison of Linear Fresnel and Parabolic Trough Collector Systems

Journal of Solar Energy Engineering ◽

10.1115/1.4027766 ◽

2014 ◽

Vol 136 (4) ◽

Cited By ~ 21

Author(s):

Heiko Schenk ◽

Tobias Hirsch ◽

Jan Fabian Feldhoff ◽

Michael Wittmann

Keyword(s):

System Analysis ◽

Storage Capacity ◽

Field Size ◽

Heat Transfer Fluid ◽

Parabolic Trough ◽

Solar Salt ◽

Parabolic Trough Collector ◽

Thermodynamic Performance ◽

The Impact ◽

And Storage

In recent years, linear Fresnel (LF) collector systems have been developed as a technical alternative to parabolic trough (PT) collector systems. While in the past, LF systems focused on low- and medium-temperature applications, today, LF systems are equipped with vacuum receivers and, therefore, can be operated with similar operating parameters as PT systems. Papers about the technical and economical comparison of specific PT and LF systems have already been published (Dersch et al., 2009, "Comparison of Linear Fresnel and Parabolic Trough Collecor Systems—System Analysis to Determine Break-Even Costs of Linear Fresnel Collectors," Proceedings of the 15th International SolarPACES Symposium, Berlin; Giostri et al. 2011, "Comparison of Two Linear Collectors in Solar Thermal Plants: Parabolic Trough vs. Fresnel," ASME 2011 5th International Conference on Energy Sustainability, Washington, DC; and Morin et al., 2012, "Comparison of Linear Fresnel and Parabolic Trough Collector Power Plants," Sol. Energy, 86(1), pp. 1–12). However, the present paper focuses on the systematic differences in optical and thermodynamic performance and the impact on the economic figures. In a first step the optical performance of typical PT and LF solar fields (SFs) has been examined, showing the differences during the course of the day and annually. Furthermore, the thermodynamic performance, depending on the operating temperature, has been compared. In a second step, the annual electricity yield of typical PT and LF plants has been examined. Solar Salt has been chosen as the heat transfer fluid. Both systems utilize the same power block (PB) and storage type. Solar field size, storage capacity, and PB electrical power are variable, while all examined configurations achieve the same annual electricity yield. As expected for molten salt systems, both systems are the most cost-effective with large storage capacities. The lower thermodynamic performance of the LF system requires a larger SF and lower specific SF costs in order to be competitive. Assuming specific PT field costs of 300 €/m2 aperture, the break-even costs of the LF system with Solar Salt range between 202 and 235 €/m2, depending on the site and storage capacity. In order to confirm the major statements, within a sensitivity analysis, it is shown that a variation of SF and storage costs does not have a significant impact on the relative break-even costs of the LF system.

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Quantifying Uncertainty through 3D Geological Modeling for Carbon Capture Utilization and Storage in the Unayzah Formation in Saudi Arabia

10.5194/egusphere-egu21-12839 ◽

2021 ◽

Author(s):

Sofia Mantilla Salas ◽

Miguel Corrales ◽

Hussein Hoteit ◽

Abdulkader Alafifi ◽

Alexandros Tasianas

Keyword(s):

Saudi Arabia ◽

Carbon Capture ◽

Large Scale ◽

Storage Capacity ◽

Co2 Storage ◽

High Energy ◽

Sequential Gaussian Simulation ◽

Storage Site ◽

The Impact ◽

And Storage

<p>The development of Carbon Capture Utilization and Storage (CCUS) technology paired with existing energy systems will facilitate a successful transition to a carbon-neutral economy that offers efficient and sustainable energy. It will also enable the survival of multiple and vital economic sectors of high-energy industries that possess few other options to decarbonize. Nowadays, just about one-ten-thousandth of the global annual emissions are being captured and geologically-stored, and therefore with today&#8217;s emission panorama, CCS large-scale deployment is more pressing than ever. In this study, a 3D model that represents the key reservoir uncertainties for a CCUS pilot was constructed to investigate the feasibility of CO2 storage in the Unayzah Formation in Saudi Arabia. The study site covers the area of the city of Riyadh and the Hawtah and Nuayyim Trends, which contain one of the most prolific petroleum-producing systems in the country. The Unayzah reservoir is highly stratified and it is subdivided into three compartments: the Unayzah C (Ghazal Member), the Unayzah B (Jawb Member), and the Unayzah A (Wudayhi and Tinat Members). This formation was deposited under a variety of environments, such as glaciofluvial, fluvial, eolian, and coastal plain. Facies probability trend maps and well log data were used to generate a facies model that accounted for the architecture, facies distribution, and lateral and vertical heterogeneity of this high complexity reservoir. Porosity and predicted permeability logs were used with Sequential Gaussian Simulation and co-kriging methods to construct the porosity and permeability models. The static model was then used for CO2 injection simulation purposes to understand the impact of the flow conduits, barriers, and baffles in CO2 flow in all dimensions. Similarly, the CO2 simulations allowed us to better understand the CO2 entrapment process and to estimate a more realistic and reliable CO2 storage capacity of the Unayzah reservoir in the area. To test the robustness of the model predictions, geological uncertainty quantification and a sensitivity analysis were run. Parameters such as porosity, permeability, pay thickness, anisotropy, and connectivity were analyzed as well as how various combinations between them affected the CO2 storage capacity, injectivity, and containment. This approach could improve the storage efficiency of CO2 exceeding 60%. The analyzed reservoir was found to be a promising storage site. The proposed workflow and findings of the static and dynamic modeling described in this publication could serve as a guideline methodology to test the feasibility of the imminent upcoming pilots and facilitate the large-scale deployment of this very promising technology.</p>

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Effect of organic maturity on shale gas genesis and pores development: A case study on marine shale in the upper Yangtze region, South China

Open Geosciences ◽

10.1515/geo-2020-0216 ◽

2020 ◽

Vol 12 (1) ◽

pp. 1617-1629

Author(s):

Kun Zhang ◽

Jun Peng ◽

Xin Wang ◽

Zhenxue Jiang ◽

Yan Song ◽

...

Keyword(s):

Organic Matter ◽

Shale Gas ◽

Sichuan Basin ◽

Storage Capacity ◽

Thermal Evolution ◽

Marine Shale ◽

The Sichuan Basin ◽

The Impact ◽

And Storage ◽

Cracking Gas

AbstractThe marine shale in southern China has undergone complex tectonic evolution with a high thermal evolution degree. Excessive thermal evolution brings certain risks to shale gas exploration and development. With the advancement of experimental methods, the evolution process of shale reservoirs can be better understood from the micro-nanoscale. This work takes the Ordovician-Silurian Wufeng and the first member of Longmaxi Formation in the Sichuan Basin and Lower Cambrian Niutitang Formation in Outer Margin of the Sichuan Basin to study the impact of maturity upon the genesis of shale gas and development features of the reservoir. A series of geochemical research methods, including TOC, gas component and gas isotope, were adopted to study the impact of different thermal evolution stages of organic matter upon the genesis of shale gas. The nanoscale micro-imaging technique, such as FIB-SEM and FIB-HIM, was used to analyze the development of OM-hosted pores. As shown from the results, when Ro = 1.2–3.5%, the marine shale gas is dominated by methane and other hydrocarbon gases, since the mixture of cracking gas from liquid hydrocarbons and kerogen-cracking gas cause the carbon isotope reversal. Besides, the pyrobitumen pores characterized by the strong connectivity and storage capacity were primarily developed. When Ro > 3.5%, the organic matter is at the graphitization stage. The shale gas is mainly composed of nitrogen at this stage. The nitrogen is originated from the atmosphere and the thermal evolution process, and the OM-hosted pores (pyrobitumen and kerogen pores) characterized by the bad connectivity and storage capacity are developed. Finally, the main component of shale gas, the genesis of shale gas and the pattern of OM-hosted pores under different thermal evolution stages of organic matter are summarized, which provide technical support for the exploration and development of shale gas.

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