Unconventional Resources最新文献

Mineralogy and geochemistry of shale from Shanxi Formation, Southern North China Basin: Implication for organic matter accumulation

Unconventional Resources

Pub Date : 2025-02-05 DOI: 10.1016/j.uncres.2025.100151

Qian Chen , Pei Li , Xiaoliang Wei , Changsheng Chen , Wei Dang , Haikuan Nie , Jinchuan Zhang

The Permian Taiyuan and Shanxi coal-bearing formations are recognized as the primary source rocks and promising shale gas reservoirs in North China. Based on lithologic observations, mineral and major elemental analyses of the Shanxi Sahle in the Southern North China Basin (SNCB), we conducted a preliminary investigation into the depositional environment, climate, and factors controlling the organic matter (OM) accumulation. The main findings are as follows: (1) The Shanxi Formation results from a transition in depositional environment, shifting from tidal flats to delta plains. The Shanxi Shale is primarily composed of clay minerals (34.24 %–75.20 %) and quartz (23.80%–46.39 %), with a notably low carbonate content (<5 %). (2) Illite in the lower sections of the Shanxi Shale is likely sourced from detrital input rather than chemical conversion, while the dissolution of potassium feldspar may account for the elevated kaolinite content. This is further supported by the oxygen level variations between the lower and upper shale intervals. Moreover, no significant positive correlation was observed between SiO₂ and Al/Na ratios, nor between clay minerals and total organic carbon (TOC) content. This suggests that the intensity of OM modification prior to diagenesis plays a pivotal role in OM accumulation, aligning with the positive correlation between inertinite proportion and TOC content. (3) Organic matter inputs from fluvial systems were likely influenced by upstream mire conditions, where precursor peat may have accumulated. Unlike marine shale, the intensity of weathering, which varies with climate and transportation distance, is considered to have significantly impacted both the maceral composition and OM richness in the tide-delta deposited Shanxi Shale.

{"title":"Mineralogy and geochemistry of shale from Shanxi Formation, Southern North China Basin: Implication for organic matter accumulation","authors":"Qian Chen , Pei Li , Xiaoliang Wei , Changsheng Chen , Wei Dang , Haikuan Nie , Jinchuan Zhang","doi":"10.1016/j.uncres.2025.100151","DOIUrl":"10.1016/j.uncres.2025.100151","url":null,"abstract":"<div><div>The Permian Taiyuan and Shanxi coal-bearing formations are recognized as the primary source rocks and promising shale gas reservoirs in North China. Based on lithologic observations, mineral and major elemental analyses of the Shanxi Sahle in the Southern North China Basin (SNCB), we conducted a preliminary investigation into the depositional environment, climate, and factors controlling the organic matter (OM) accumulation. The main findings are as follows: (1) The Shanxi Formation results from a transition in depositional environment, shifting from tidal flats to delta plains. The Shanxi Shale is primarily composed of clay minerals (34.24 %–75.20 %) and quartz (23.80%–46.39 %), with a notably low carbonate content (<5 %). (2) Illite in the lower sections of the Shanxi Shale is likely sourced from detrital input rather than chemical conversion, while the dissolution of potassium feldspar may account for the elevated kaolinite content. This is further supported by the oxygen level variations between the lower and upper shale intervals. Moreover, no significant positive correlation was observed between SiO<sub>2</sub> and Al/Na ratios, nor between clay minerals and total organic carbon (TOC) content. This suggests that the intensity of OM modification prior to diagenesis plays a pivotal role in OM accumulation, aligning with the positive correlation between inertinite proportion and TOC content. (3) Organic matter inputs from fluvial systems were likely influenced by upstream mire conditions, where precursor peat may have accumulated. Unlike marine shale, the intensity of weathering, which varies with climate and transportation distance, is considered to have significantly impacted both the maceral composition and OM richness in the tide-delta deposited Shanxi Shale.</div></div>","PeriodicalId":101263,"journal":{"name":"Unconventional Resources","volume":"6 ","pages":"Article 100151"},"PeriodicalIF":0.0,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143369857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimization and potential assessment of CO2 geological storage caprock in the saline aquifers of the Qingjiang Basin, middle and lower reaches of the Yangtze River

Unconventional Resources

Pub Date : 2025-02-05 DOI: 10.1016/j.uncres.2025.100155

Yuchen Tian , Shiqi Liu , Sijian Zheng , Shuxun Sang , Yinghai Liu , Shiheng Chen , Helong Zhang , Yanzhi Liu , Yuntian Jiang , Zekun Yue , Wenkai Wang

CO₂ geological storage is seen as a key technology for reaching carbon neutrality. The Qingjiang Basin, located in Jiangxi, China, is experiencing rapid industrialization and urbanization leading to increased natural resource and energy consumption. The basin is located in the middle and lower reaches of the Yangtze River. A study was conducted in response to the geological characteristics of the Qingjiang Basin to optimize caprock for CO₂ geological storage in saline aquifers and assess its potential. The research initially outlined the regional geological background of the Qingjiang Basin, including its tectonic position, stratigraphic distribution, sedimentary features, and the division of secondary structural units. By combining the regional geological conditions, the study analyzed the basin's formation and evolution history, sedimentary characteristics, reservoir and caprock development features, and geothermal geological conditions. This analysis provided critical geological factor evaluations for CO₂ storage. Employing the calculation method proposed by the Carbon Sequestration Leadership Forum (CSLF), the study estimated the CO₂ storage capacity in the deep saline aquifers of the Qingjiang Basin. The study revealed a total storage potential of 6.76 × 10⁸ tons, with the central depression zone having the greatest potential, accounting for over 90 % of the total. Based on these findings, a hierarchical structure model was constructed, including three evaluation index layers and 21 evaluation indicators. A fuzzy comprehensive evaluation method combining the analytic hierarchy process and weighted judgment method was used to assess the suitability of CO₂ geological storage in the Qingjiang Basin. The evaluation results indicated that the central depression zone had the highest comprehensive score and the best suitability for storage, making it the most favorable area for CO₂ storage in the Qingjiang Basin. The research outcomes can provide theoretical support for advancing the study of CO₂ saline aquifer storage in the lower reaches of the Yangtze River region in China.

{"title":"Optimization and potential assessment of CO2 geological storage caprock in the saline aquifers of the Qingjiang Basin, middle and lower reaches of the Yangtze River","authors":"Yuchen Tian , Shiqi Liu , Sijian Zheng , Shuxun Sang , Yinghai Liu , Shiheng Chen , Helong Zhang , Yanzhi Liu , Yuntian Jiang , Zekun Yue , Wenkai Wang","doi":"10.1016/j.uncres.2025.100155","DOIUrl":"10.1016/j.uncres.2025.100155","url":null,"abstract":"<div><div>CO<sub>2</sub> geological storage is seen as a key technology for reaching carbon neutrality. The Qingjiang Basin, located in Jiangxi, China, is experiencing rapid industrialization and urbanization leading to increased natural resource and energy consumption. The basin is located in the middle and lower reaches of the Yangtze River. A study was conducted in response to the geological characteristics of the Qingjiang Basin to optimize caprock for CO<sub>2</sub> geological storage in saline aquifers and assess its potential. The research initially outlined the regional geological background of the Qingjiang Basin, including its tectonic position, stratigraphic distribution, sedimentary features, and the division of secondary structural units. By combining the regional geological conditions, the study analyzed the basin's formation and evolution history, sedimentary characteristics, reservoir and caprock development features, and geothermal geological conditions. This analysis provided critical geological factor evaluations for CO<sub>2</sub> storage. Employing the calculation method proposed by the Carbon Sequestration Leadership Forum (CSLF), the study estimated the CO<sub>2</sub> storage capacity in the deep saline aquifers of the Qingjiang Basin. The study revealed a total storage potential of 6.76 × 10<sup>8</sup> tons, with the central depression zone having the greatest potential, accounting for over 90 % of the total. Based on these findings, a hierarchical structure model was constructed, including three evaluation index layers and 21 evaluation indicators. A fuzzy comprehensive evaluation method combining the analytic hierarchy process and weighted judgment method was used to assess the suitability of CO<sub>2</sub> geological storage in the Qingjiang Basin. The evaluation results indicated that the central depression zone had the highest comprehensive score and the best suitability for storage, making it the most favorable area for CO<sub>2</sub> storage in the Qingjiang Basin. The research outcomes can provide theoretical support for advancing the study of CO<sub>2</sub> saline aquifer storage in the lower reaches of the Yangtze River region in China.</div></div>","PeriodicalId":101263,"journal":{"name":"Unconventional Resources","volume":"6 ","pages":"Article 100155"},"PeriodicalIF":0.0,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143369858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring geothermal energy as a sustainable source of energy: A systemic review

Unconventional Resources

Pub Date : 2025-02-03 DOI: 10.1016/j.uncres.2025.100149

Charity M. Nkinyam , Chika Oliver Ujah , Christian O. Asadu , Daramy V.V. Kallon

Geothermal energy is a renewable energy source with potential to facilitate the world's transition to clean and sustainable energy. Despite its capabilities, geothermal energy currently accounts for barely 0.34 % of the global energy contribution. However, its ability to provide consistent and reliable electrical power especially for base load demand positions it as a competitive alternative to fossil fuels. The installed capacity of geothermal generation has increased from 9791 MWe in 2009 to 16,318 MWe by the end of 2023, with over 32 countries actively developing their geothermal resources. An in-depth literature review explores the evolution of geothermal energy as a clean energy option, illustrating its significant impact and the challenges it faces. To enhance its competitiveness relative to fossil fuels, which benefit from established support and subsidies, geothermal energy requires government backing in the form of favorable feed-in tariffs and preferential tax treatment. This review emphasizes geothermal energy's potential, extraction technologies, geothermal power plants, geothermal applications, and areas for further research. Additionally, it outlines current research initiatives and provides recommendations for stakeholders to promote geothermal energy as a vital component of a clean energy future.

{"title":"Exploring geothermal energy as a sustainable source of energy: A systemic review","authors":"Charity M. Nkinyam , Chika Oliver Ujah , Christian O. Asadu , Daramy V.V. Kallon","doi":"10.1016/j.uncres.2025.100149","DOIUrl":"10.1016/j.uncres.2025.100149","url":null,"abstract":"<div><div>Geothermal energy is a renewable energy source with potential to facilitate the world's transition to clean and sustainable energy. Despite its capabilities, geothermal energy currently accounts for barely 0.34 % of the global energy contribution. However, its ability to provide consistent and reliable electrical power especially for base load demand positions it as a competitive alternative to fossil fuels. The installed capacity of geothermal generation has increased from 9791 MWe in 2009 to 16,318 MWe by the end of 2023, with over 32 countries actively developing their geothermal resources. An in-depth literature review explores the evolution of geothermal energy as a clean energy option, illustrating its significant impact and the challenges it faces. To enhance its competitiveness relative to fossil fuels, which benefit from established support and subsidies, geothermal energy requires government backing in the form of favorable feed-in tariffs and preferential tax treatment. This review emphasizes geothermal energy's potential, extraction technologies, geothermal power plants, geothermal applications, and areas for further research. Additionally, it outlines current research initiatives and provides recommendations for stakeholders to promote geothermal energy as a vital component of a clean energy future.</div></div>","PeriodicalId":101263,"journal":{"name":"Unconventional Resources","volume":"6 ","pages":"Article 100149"},"PeriodicalIF":0.0,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Offshore wind technology of India: Potential and perspectives

Unconventional Resources

Pub Date : 2025-01-28 DOI: 10.1016/j.uncres.2025.100150

Tejaswini Gautam , Anirbid Sircar , Kriti Yadav

India has 7600 km of coastline, making offshore wind energy a promising sustainable energy source that could satisfy the country's energy requirements. In contrast to onshore equivalents, offshore wind energy systems provide several benefits like availability of high and steady wind speeds, huge energy potential, and less noise. This study reviews the advancement in offshore wind technology and discusses the recent advancement in offshore wind turbines, foundations, and transmission systems. It highlights the different types of controls and the reliability of turbines along with some general maintenance issues encountered in offshore wind turbines. The different types of foundations and their characteristic features of recent transmission systems is also discussed. The offshore wind energy potential of India was reviewed. The three models employed by India to attract Indian and foreign investors serve as the scope of the framework for this study. Models A, B, and C represent the viability gap funding model, non-viability gap funding model (with exclusivity over the seabed), and non-viability gap funding model (without exclusivity over the seabed). The available site characteristics of the most promising regions for offshore wind energy, Gujarat and Tamil Nadu were outlined. The study discusses the feasibility of offshore wind energy in India and the CAPEX, OPEX, and levelized cost of energy for generated energy considering the met-ocean, wind and geotechnical characteristics of the potential offshore wind farm regions. This study includes the role of subsidies in the cost of offshore wind energy in India. The prevalent policies and regulatory frameworks for the development of offshore wind energy in India are outlined with the comparative study of other offshore wind markets. This study aims to present the technological advancement and availability of technologies in offshore wind energy along with the potential of offshore energy development in India with its characteristic engineering, financial, environmental, and regulatory features.

{"title":"Offshore wind technology of India: Potential and perspectives","authors":"Tejaswini Gautam , Anirbid Sircar , Kriti Yadav","doi":"10.1016/j.uncres.2025.100150","DOIUrl":"10.1016/j.uncres.2025.100150","url":null,"abstract":"<div><div>India has 7600 km of coastline, making offshore wind energy a promising sustainable energy source that could satisfy the country's energy requirements. In contrast to onshore equivalents, offshore wind energy systems provide several benefits like availability of high and steady wind speeds, huge energy potential, and less noise. This study reviews the advancement in offshore wind technology and discusses the recent advancement in offshore wind turbines, foundations, and transmission systems. It highlights the different types of controls and the reliability of turbines along with some general maintenance issues encountered in offshore wind turbines. The different types of foundations and their characteristic features of recent transmission systems is also discussed. The offshore wind energy potential of India was reviewed. The three models employed by India to attract Indian and foreign investors serve as the scope of the framework for this study. Models A, B, and C represent the viability gap funding model, non-viability gap funding model (with exclusivity over the seabed), and non-viability gap funding model (without exclusivity over the seabed). The available site characteristics of the most promising regions for offshore wind energy, Gujarat and Tamil Nadu were outlined. The study discusses the feasibility of offshore wind energy in India and the CAPEX, OPEX, and levelized cost of energy for generated energy considering the met-ocean, wind and geotechnical characteristics of the potential offshore wind farm regions. This study includes the role of subsidies in the cost of offshore wind energy in India. The prevalent policies and regulatory frameworks for the development of offshore wind energy in India are outlined with the comparative study of other offshore wind markets. This study aims to present the technological advancement and availability of technologies in offshore wind energy along with the potential of offshore energy development in India with its characteristic engineering, financial, environmental, and regulatory features.</div></div>","PeriodicalId":101263,"journal":{"name":"Unconventional Resources","volume":"6 ","pages":"Article 100150"},"PeriodicalIF":0.0,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhancing heat recovery efficiency in chimney exhaust systems using thermoelectric generators – Thermal modeling and parametric analysis

Unconventional Resources

Pub Date : 2025-01-15 DOI: 10.1016/j.uncres.2025.100148

Obeida Farhat , Mahmoud Khaled , Jalal Faraj , Khaled Chahine , Farouk Hachem , Cathy Castelain

The rising demand for sustainable energy solutions has made the utilization of waste heat from industrial processes a priority. Thermoelectric generators present an effective method for recovering and converting waste heat into useable electrical energy, therefore enhancing energy efficiency and sustainability. This study presents a parametric study of thermoelectric generators for waste heat recovery from heating chimney exhaust. In order to investigate the impact of placing the thermoelectric generators at different locations, simplified thermal resistance modeling was performed. Performance metrics demonstrate that the positioning of the thermoelectric generator site can bring about major improvements including thermal resistance, generated power, temperature of water heated, and energy conversion efficiency, which ranged from 0.57 % to 5.6 %, depending on thermoelectric generators configuration and operating parameters. By positioning thermoelectric generators on the exterior walls of the exhaust pipe, close to the heat source, a significant amount of electrical power—up to 37.67 W—could be produced. Additionally, a parametric analysis was conducted on important operating parameters: the mass flow rate and input temperatures of the exhaust gas and water. The application of 6 different cases showed that Case 5 of thermoelectric generator modules, with ṁ_g = 0.25 kg/s, T_g,i = 390 °C, ṁ_w = 0.3 kg/s and T_w,i = 20 °C, was the optimal condition, based on observations. The results demonstrate notable advancements in power production and energy recovery, and includes clear recommendations for future research that will bring about a shift in the direction of sustainable industrial operations.

{"title":"Enhancing heat recovery efficiency in chimney exhaust systems using thermoelectric generators – Thermal modeling and parametric analysis","authors":"Obeida Farhat , Mahmoud Khaled , Jalal Faraj , Khaled Chahine , Farouk Hachem , Cathy Castelain","doi":"10.1016/j.uncres.2025.100148","DOIUrl":"10.1016/j.uncres.2025.100148","url":null,"abstract":"<div><div>The rising demand for sustainable energy solutions has made the utilization of waste heat from industrial processes a priority. Thermoelectric generators present an effective method for recovering and converting waste heat into useable electrical energy, therefore enhancing energy efficiency and sustainability. This study presents a parametric study of thermoelectric generators for waste heat recovery from heating chimney exhaust. In order to investigate the impact of placing the thermoelectric generators at different locations, simplified thermal resistance modeling was performed. Performance metrics demonstrate that the positioning of the thermoelectric generator site can bring about major improvements including thermal resistance, generated power, temperature of water heated, and energy conversion efficiency, which ranged from 0.57 % to 5.6 %, depending on thermoelectric generators configuration and operating parameters. By positioning thermoelectric generators on the exterior walls of the exhaust pipe, close to the heat source, a significant amount of electrical power—up to 37.67 W—could be produced. Additionally, a parametric analysis was conducted on important operating parameters: the mass flow rate and input temperatures of the exhaust gas and water. The application of 6 different cases showed that Case 5 of thermoelectric generator modules, with ṁ<sub>g</sub> = 0.25 kg/s, T<sub>g,i</sub> = 390 °C, ṁ<sub>w</sub> = 0.3 kg/s and T<sub>w,i</sub> = 20 °C, was the optimal condition, based on observations. The results demonstrate notable advancements in power production and energy recovery, and includes clear recommendations for future research that will bring about a shift in the direction of sustainable industrial operations.</div></div>","PeriodicalId":101263,"journal":{"name":"Unconventional Resources","volume":"6 ","pages":"Article 100148"},"PeriodicalIF":0.0,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Heating water using the hot air of condensers and tubes-and-fins heat exchangers – Thermodynamic modeling and parametric study with economic and environmental insights

Unconventional Resources

Pub Date : 2025-01-10 DOI: 10.1016/j.uncres.2025.100146

Ahmad Al Takash , Jalal Faraj , Sary Awad , Hicham El Hage , Mahmoud Khaled

Recovering the waste heat from condensers of Heating, Ventilating and Air Conditioning (HVAC) is taking big importance nowadays in the building energy management sector. Advances in this area are still needed due to the high amount of heat released from the condensers versus the low effectiveness of and high volume of the heat recovery medium. As compact and high effectiveness heat exchangers, tubes and fins heat exchangers constitute a potential candidate to overcome the concerns. In this context, the primary goal of this research is to investigate the effect of employing tubes and fins heat exchangers to recover heat from the condenser. To accomplish this goal, a thermodynamic modeling, in addition to analytical approach of the system performance were introduced. Then, a parametric study was performed to examine the effect of the mass flow rate of air and water on the suggested heat recovery system. Finally, economic, and environmental insights based on the energy analysis are presented. It was observed that increasing the mass flow rate from 0.417 kg/s to 2.5 kg/s enhanced the power output from 14.5 kW to 15.1 kW. Similarly, lowering the water inlet temperature from 35 °C to 15 °C increased the power output from 11.28 kW to 15 kW The study highlighted the notable savings with various COP and cooling load, particularly at low COP and a cooling load of 30 kW. Moreover, the investigation revealed that maintaining a constant COP of 2 and increasing cooling loads contributed to higher CO2 emission reduction, ranging from 3.8 kg at 5 kW to 16.5 kg at 25 kW. The findings confirm that the suggested heat recovery system is effective in reducing energy waste and minimizing environmental impact. Finally, it was observed that the proposed system has 95 % capacity of heat recovery.

{"title":"Heating water using the hot air of condensers and tubes-and-fins heat exchangers – Thermodynamic modeling and parametric study with economic and environmental insights","authors":"Ahmad Al Takash , Jalal Faraj , Sary Awad , Hicham El Hage , Mahmoud Khaled","doi":"10.1016/j.uncres.2025.100146","DOIUrl":"10.1016/j.uncres.2025.100146","url":null,"abstract":"<div><div>Recovering the waste heat from condensers of Heating, Ventilating and Air Conditioning (HVAC) is taking big importance nowadays in the building energy management sector. Advances in this area are still needed due to the high amount of heat released from the condensers versus the low effectiveness of and high volume of the heat recovery medium. As compact and high effectiveness heat exchangers, tubes and fins heat exchangers constitute a potential candidate to overcome the concerns. In this context, the primary goal of this research is to investigate the effect of employing tubes and fins heat exchangers to recover heat from the condenser. To accomplish this goal, a thermodynamic modeling, in addition to analytical approach of the system performance were introduced. Then, a parametric study was performed to examine the effect of the mass flow rate of air and water on the suggested heat recovery system. Finally, economic, and environmental insights based on the energy analysis are presented. It was observed that increasing the mass flow rate from 0.417 kg/s to 2.5 kg/s enhanced the power output from 14.5 kW to 15.1 kW. Similarly, lowering the water inlet temperature from 35 °C to 15 °C increased the power output from 11.28 kW to 15 kW The study highlighted the notable savings with various COP and cooling load, particularly at low COP and a cooling load of 30 kW. Moreover, the investigation revealed that maintaining a constant COP of 2 and increasing cooling loads contributed to higher CO2 emission reduction, ranging from 3.8 kg at 5 kW to 16.5 kg at 25 kW. The findings confirm that the suggested heat recovery system is effective in reducing energy waste and minimizing environmental impact. Finally, it was observed that the proposed system has 95 % capacity of heat recovery.</div></div>","PeriodicalId":101263,"journal":{"name":"Unconventional Resources","volume":"6 ","pages":"Article 100146"},"PeriodicalIF":0.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhanced dry SO₂ capture estimation using Python-driven computational frameworks with hyperparameter tuning and data augmentation

Unconventional Resources

Pub Date : 2025-01-10 DOI: 10.1016/j.uncres.2025.100145

Robert Makomere , Hilary Rutto , Alfayo Alugongo , Lawrence Koech , Evans Suter , Itumeleng Kohitlhetse

Dry flue gas desulfurization is an invaluable technique to curb sulfur dioxide. In this study, an in-depth comparison of regression models for predicting sulfur dioxide removal was performed. The data-driven models executed were multilayer perceptron, support vector regressor, random forest, categorical boosting, and light gradient boosting machine. The limited experimental samples were magnified to 342 datasets using the random interpolation and random scaling augmentation procedures and analyzed using the empirical cumulative distribution function and box plots. Model training incorporated grid search with cross-validation to identify the optimal hyperparameter sets. The practicality of the resultant customized models was quantified by leveraging the coefficient of determination, mean squared error and root mean square error. The model complexity arising from hyperparameter configurations was appraised based on the Bayesian information criterion and the Akaike information criterion. SHapley Additive exPlanations was essential for comprehending the prediction mechanism through feature significance and the impact of varying feature thresholds on the predicted output. Results obtained evidence that random forest obtained the strongest accuracy, and generalizability from the high coefficient of determination, and lowest error scores. In addition, it was the least convoluted algorithm according to Akaike information criterion and Bayesian information criterion assessments. The SHapley Additive exPlanations analysis revealed that each model interacts with the metadata features uniquely during training, contributing to a varied selection of dominant factors. This paper endorses the technical implementation of machine learning in dry sulfation processes and provides insights into how computer systems perceive data characteristics and make forecasts.

{"title":"Enhanced dry SO₂ capture estimation using Python-driven computational frameworks with hyperparameter tuning and data augmentation","authors":"Robert Makomere , Hilary Rutto , Alfayo Alugongo , Lawrence Koech , Evans Suter , Itumeleng Kohitlhetse","doi":"10.1016/j.uncres.2025.100145","DOIUrl":"10.1016/j.uncres.2025.100145","url":null,"abstract":"<div><div>Dry flue gas desulfurization is an invaluable technique to curb sulfur dioxide. In this study, an in-depth comparison of regression models for predicting sulfur dioxide removal was performed. The data-driven models executed were multilayer perceptron, support vector regressor, random forest, categorical boosting, and light gradient boosting machine. The limited experimental samples were magnified to 342 datasets using the random interpolation and random scaling augmentation procedures and analyzed using the empirical cumulative distribution function and box plots. Model training incorporated grid search with cross-validation to identify the optimal hyperparameter sets. The practicality of the resultant customized models was quantified by leveraging the coefficient of determination, mean squared error and root mean square error. The model complexity arising from hyperparameter configurations was appraised based on the Bayesian information criterion and the Akaike information criterion. SHapley Additive exPlanations was essential for comprehending the prediction mechanism through feature significance and the impact of varying feature thresholds on the predicted output. Results obtained evidence that random forest obtained the strongest accuracy, and generalizability from the high coefficient of determination, and lowest error scores. In addition, it was the least convoluted algorithm according to Akaike information criterion and Bayesian information criterion assessments. The SHapley Additive exPlanations analysis revealed that each model interacts with the metadata features uniquely during training, contributing to a varied selection of dominant factors. This paper endorses the technical implementation of machine learning in dry sulfation processes and provides insights into how computer systems perceive data characteristics and make forecasts.</div></div>","PeriodicalId":101263,"journal":{"name":"Unconventional Resources","volume":"6 ","pages":"Article 100145"},"PeriodicalIF":0.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Integrating solar and wind energy into the electricity grid for improved power accessibility

Unconventional Resources

Pub Date : 2025-01-01 DOI: 10.1016/j.uncres.2024.100129

Collins N. Nwagu , Chika Oliver Ujah , Daramy V.V. Kallon , Victor S. Aigbodion

A rise in the need for the integration of renewable energy sources, such as wind and solar power, has been attributed to the search for sustainable energy solutions. To strengthen community grids and improve access to electricity, this article investigates the potential of combining solar and wind hybrid systems. This is viable approach to address energy-related issues, like grid dependability, energy accessibility, and greenhouse gas reduction. This research focuses on the examination of the environmental, technological, financial, and operational effects, and features of hybrid solar and wind systems for grid support. To further demonstrate the practical uses and advantages of such hybrid systems; case studies are presented. This study attempts to shed light on how solar and wind systems can affect grid resilience, increase electricity accessibility, and shape the direction for sustainable energy in the future. The obstacles preventing the broad use of a hybrid system for grid support were investigated, and the intricacies required in implementing such systems at a large scale are comprehensively presented. It was observed that developments of demand-side management, energy storage technology, and hybrid system optimization algorithms would improve the dependability, effectiveness, and cost of the hybrid system. In summary, the motivation of this study was to provide an effective tool for the interaction of hybrid solar and wind systems in the changing the energy landscape, in order to provide communities with dependable access to electricity, and fostering a more sustainable future. This work offers stakeholders insights into utilizing the hybrid system for electricity access and shift towards cleaner and renewable energy.

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引用次数: 0

Insights from field applications of miscible gases based EOR for unconventional oil reservoirs: A review

Unconventional Resources

Pub Date : 2025-01-01 DOI: 10.1016/j.uncres.2024.100132

Dheiaa Alfarge , Ahmed M. Aljarah , Najeh Alali

The oil industry has experienced notable changes due to the development of unconventional liquids rich reservoirs over the past decade. Shale oil reservoirs have become a primary focus for oil and gas investors as traditional onshore deposits have dwindled. These non-traditional reserves hold substantial original oil, but their recovery rate is less than 10 %. Utilizing miscible gas-based enhanced oil recovery (EOR) techniques, which are effective in tight oil reservoirs, has the potential to enhance oil recovery in these formations.

This research conducts an analysis of the feasibility of using miscible gas-based EOR methods in shale oil reservoirs. Initially, the EOR mechanisms involving various miscible gases are introduced, including molecular diffusion, adsorption, swelling, and viscosity reduction, are summarized and explored. Subsequently, the impact of operational factors such as injection rate, cycle count, and injection duration on the efficacy of miscible gases in boosting oil recovery from unconventional oil reservoirs are examined. Moreover, the outcomes of pilot tests employing diverse miscible gas-based EOR in shale oil reservoirs are discussed. The findings reveal that molecular diffusion is the primary mechanism enhancing oil recovery in shale oil reservoirs. This mechanism positively influences the oil recovery factor through CO₂ injection, while it has no effect when injecting natural gas. Adsorption, however, negatively affects well performance in CO₂-EOR. Additionally, the number of huff-n-puff cycles negatively impacts CO₂-EOR but benefits NGs-EOR. Overall, the performance of natural gas (NG) injection surpasses that of CO₂ injection in enhancing oil recovery in field pilot tests. Moreover, the study concludes that unconventional reservoirs respond much quicker to injected natural gas compared to CO₂.

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引用次数: 0

Balancing conflicting objectives in pre-salt reservoir development: A robust multi-objective optimization framework

Unconventional Resources

Pub Date : 2025-01-01 DOI: 10.1016/j.uncres.2024.100130

Auref Rostamian, Amir Davari Malekabadi, Marx Vladimir De Souda Miranda, Vinicius Edurado Botechia, Denis José Schiozer

Optimizing production strategies for gas and oil fields is a critical challenge in petroleum engineering as it involves balancing multiple and often conflicting objectives, for instance, enhancing production rates, reducing operational costs, and mitigating the environmental effects of cumulative water or gas production. This study aims to develop and apply a robust multi-objective optimization framework to the UNISIM-II-D reservoir, which represents Brazilian pre-salt fields on nine representative models (RMs) to address geological uncertainties while considering three economic scenarios. The study focuses on maximizing expected monetary value (EMV) and the net present value of RM4 considering economic uncertainty (NPVeco of RM4), of the most pessimistic scenario among the RMs. The optimization variables are location, type (injection or production), and number of wells, while the non-dominated sorting genetic algorithm II (NSGA-II) is employed for multi-objective optimization. The study indicates that prioritizing EMV, the primary objective function, does not inevitably result in the NPVeco of RM4 achieving its optimal or near-optimal value. However, by employing the proposed framework, a 3 % improvement in EMV and a 28 % enhancement in the NPVeco of RM4 is achieved compared to the single objective optimization of EMV, which highlights the strength and robustness of the framework.

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引用次数: 0