One of the most popular tools for dealing with the seepage problem in embankment dams is using different types and shapes of downstream drains. So, the paper presents a comprehensive study of the different drainage systems through such dams. Many earth dam models are investigated through the SEEP/W model representing different dimensions and geometry of downstream drains. A comparison is carried out between the present study and previous experimental and numerical studies and the results of the present study are almost close to the previous studies. The present work concludes that the most influential factor in a horizontal drain is the length, and the thickness has a negligible effect. The reasonable length ratio of a horizontal drain (L/B) is about 0.34 according to the minimum seepage. The angle of toe drains has a slight effect on the different seepage parameters. The performance of the inclined chimney drain is better than the vertical drain to control the seepage.

The seepage study through earth dams is very essential for the design and construction processes of such dams to ensure the needed safety and efficient performance. The present study focuses on the seepage flow through zoned embankment dams by introducing a numerical analysis using the Seep/w numerical model. The main objective of the study is to investigate the different effects of the dam zones' thickness and side slopes on seepage through such dams to achieve the most suitable dimensions and geometry of the different zones. First, the Seep/w is used to analyze the problem of seepage through earth dams with an internal core. The present obtained results and the results of other previous experimental and analytical studies are almost close to each other. The present work proves that the best relative thickness of the inner, transition, and outer zones (t1:t2:t3) according to the minimum seepage and cost of the used materials is 2:1.5:1.5 respectively. At the same time, it is proven that the reasonable optimum side slopes (H:V) of the inner, transition, and outer zones are 1:1.75, 1.25:1, and 3.75:1 respectively.

Mining activities often leave behind a legacy of environmental challenges, with aging tailings ponds representing a significant concern due to their potential for leachate formation and subsequent contaminant release. Thus, this study employs Electrical Resistivity Tomography (ERT) to investigate the intricate pathways of leachate within an aging mining tailings pond, addressing the pressing environmental and human health concerns associated with potential contaminant release. Ten 2D ERT profiles were acquired at the El Mochito mine waste site, covering an area of approximately half a square kilometer. These profiles, ranging in length from 104 to 363 m, provided insights into subsurface conditions down to a maximum depth of 60 m. The subsurface mapping of the ERT data showed three different geoelectric layers. The uppermost layer, with a thickness of approximately 2.5 m and resistivity values ranging from 60 to 100 Ohm.m, was identified as a dry tailing/soil zone. Beneath it, the second layer exhibited moderately resistive values (30–60 Ohm.m) with varying thicknesses of 10–20 m, signifying a percolation/leaching zone (semi-saturated zone). The third layer, characterized by substantially low resistivity (1–30 Ohm.m), indicated saturation and the presence of conductive materials, strongly suggesting active leaching. Based on these findings, this study recommends further investigation through geochemical analysis of subsurface samples and more advanced geophysical imaging techniques to validate the distribution of anomalous zones and delineate remediation pathways. This study lays the foundation for future comprehensive research that will integrate geophysical surveys with geochemical analysis and establish 4D modeling techniques to monitor pollutant penetration over time, with a particular focus on mine waste tailings mapping. Plus, this study contributes valuable insights into the characterization of leachate pathways within mining tailings ponds, offering a foundation for informed environmental management and remediation strategies.

The accurate characterization and mapping of low-grade ore deposits necessitate the utilization of a robust exploration technique. Induced polarization (IP) tomography is a powerful geophysical method for mineral exploration. An integrated survey using electrical resistivity tomography (ERT) and IP was employed in this study to characterize and map (Zn-Pb-Ag) ore deposits in NE New Brunswick, Canada. The survey encompassed twelve parallel lines across the study area. The 2D and 3D inversion of the results provided a detailed image of the resistivity and chargeability ranges of subsurface formations. The boundaries of sulfide mineralization were determined based on resistivity values of (700–2000 Ohm.m) and chargeability values of (3.5 mV/V) and were found to be located at an approximate depth of 80–150 m from the surface. The findings were validated through a comparison with data from borehole logs and mineralogy data analysis. The size and shape of sulfide deposits were successfully characterized and mapped in the study area using this cost-effective mapping approach.

Over the last two decades, extensive research has focused on enhancing operational efficiency, emission reduction, and technological advancements in combined cycle power plants. This study conducts a comprehensive bibliometric analysis encompassing over 4100 peer-reviewed publications within the Scopus database (2000–2022) related to combined cycle power plants. The outcomes reveal a burgeoning global research landscape, primarily led by the United States, China, Italy, and the United Kingdom. Encompassing diverse domains such as engineering, energy, environment, and others, this research delves into technical areas like carbon capture, exergy analysis, and optimization, while hinting at emerging research directions involving machine learning and power-to-gas technologies. Renowned authors such as Bolland, Tsatsaronis, and Dincer, alongside influential institutions like Tsinghua University and the Norwegian University of Science and Technology, form significant research networks. International collaboration underscores widespread knowledge exchange, with the United States and China leading in total citations, while Italy boasts the highest average citations per article. A comprehensive analysis of keywords underscores the interdisciplinary nature of research, spanning technical, economic, and environmental dimensions. Further affirmation is found in the extensive publication span across general energy and specialized thermoscience journals. This study offers a comprehensive overview of research productivity, impact, and trends in combined cycle power plant research over the past two decades, providing actionable insights for strategic research planning and global performance enhancement.

As the demand for energy continues to rise, it becomes increasingly crucial to explore new energy resources and enhance the efficiency of existing ones. Combined Cycle Power Plants (CCPPs) play a pivotal role in improving efficiency and electricity generation. However, conducting a comprehensive performance analysis is essential to maintain optimal operating conditions. This paper presents a case study involving energy and exergy analyses of a 750 MW CCPP located in Assiut, Egypt. The study's primary objective is to assess the energy efficiency of the plant and identify opportunities for enhancement. The findings indicate that the combustion chambers are the primary contributors to exergy destruction, accounting for 53.3% of the total exergy loss, followed by heat recovery steam generators (HRSGs) at 32%, compressors at 5.3%, steam turbines at 5%, gas turbines at 2.3%, and cooling systems at 1.7%. Additionally, the research highlights that the energy and exergy efficiencies for the entire plant stand at 33.5% and 34.6%, respectively.

This study demonstrates the potential of exergy analysis as a tool for identifying inefficiencies within complex systems and prioritizing improvements. Specifically targeting the most inefficient components can lead to the greatest gains in overall system efficiency. To illustrate this point, the authors conducted an energy and exergy assessment of a gas turbine power plant located in Assiut, Egypt. The results revealed that the combustion chamber was the primary source of exergy destruction, indicating that this component has the greatest potential for improvement. The gas turbine was found to have the highest exergy efficiency at 95.3%, followed by the air compressor at 87.4%, while the combustion chamber had an exergy efficiency of 71.2%. The overall energy and exergy efficiency of the system were 28.8% and 27.17%, respectively. The study also highlights the impact of ambient temperature on efficiency and losses, with higher temperatures leading to reduced efficiency and increased exergy destruction. This underscores the need for optimization strategies to mitigate the impact of ambient temperature and maximize plant performance.

Thermal power plants are pivotal in meeting global energy demands, yet enhancing their efficiency and sustainability remains an enduring challenge. While previous studies have scrutinized energy and exergy analyses of distinct plant components, there's a scarcity of comprehensive reviews integrating findings across diverse plant types. This paper bridges this gap by presenting a comprehensive synthesis of recent advancements in energy and exergy studies across coal, gas, biomass, oil, and combined cycle plants. The review focuses on critical aspects: optimizing operations through modeling and advanced controls, economic evaluations encompassing costs and revenue, and assessing environmental impacts such as emissions and water use. Achieving a balance between performance, cost-effectiveness, and environmental responsibility is crucial for sustainable thermal power generation worldwide. It requires an integrated approach that considers technical, economic, and environmental factors to ensure efficiency, profitability, and minimal adverse effects on health and climate. Key findings emphasize that, in most cases, the boiler emerges as the primary source of exergy destruction, accounting for over 50% of losses across varied plant configurations. Turbines and condensers also significantly contribute to energy losses. Supercritical and ultra-supercritical power plants exhibit higher efficiencies compared to subcritical counterparts. Integrating waste-to-energy technologies with coal plants holds promise, offering efficiency improvements and reduced environmental impact. Optimizing parameters such as pressure and temperature, along with component advancements, shows potential in curbing losses. These optimization endeavors have showcased a notable up to 6% enhancement in exergy efficiency. This review underscores the critical role of ongoing thermodynamic modeling and assessments in steering towards more sustainable thermal power generation. In summary, this paper delivers valuable insights into performance benchmarks and delineates effective strategies for augmenting thermal power plant efficiency through exhaustive energy and exergy analyses.