WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7150

Browse

Search Results

Now showing 1 - 10 of 29
  • Article
    Sustainable Recovery of Critical Raw Materials From Geothermal Igneous Systems: Geochemical, Mineralogical, and Techno-Economic Insights from the Dikili-Bergama Field (Western Anatolia, Turkiye)
    (Elsevier, 2026) Ayzit, Tolga; Baba, Alper
    The sustainable co-extraction of critical raw materials (CRMs) with renewable geothermal energy offers a dual pathway to support the circular economy and low-carbon transition. In this study, an integrated geochemical and mineralogical approach is used to comprehensively assess the recoverable lithium (Li) boron (B), strontium (Sr) and other critical raw materials in the geothermal reservoirs of the Dikili-Bergama region Turkiye. A geochemical analysis was carried out by systematic sampling and multi-element testing of geothermal water and reservoir rock. Hydrogeochemical studies of the geothermal fluids indicated the presence of remarkable concentrations of B (4.6 ppm), Sr (2.8 ppm) and Li (1.2 ppm), suggesting the possibility of active leaching processes in the deposit. Mineralogical studies using X-ray diffraction (XRD) have revealed a number of secondary mineral phases, such as quartz and labradorite, indicating the interaction between water and rock. These interactions affect not only the permeability and porosity of the deposit, but also the mobilization and precipitation of CRMs. A techno-economic analysis will be used to identify potential synergies that could improve the economic feasibility of geothermal projects in the region. The Monte Carlo simulation has shown that the Dikili-Bergama geothermal reservoirs have a potential of similar to 712 tons of Li. In this study, the CRM potential that emerged during the geothermal energy exploitation process in the region was calculated. The temporality and the process of obtaining are completely related to the extraction technology. This offers the dual benefit of renewable energy and strategic mineral extraction, contributing to sustainable resource management in volcanic environments.
  • Article
    Hydrogeochemical Assessment and Health Risks of Groundwater in Sahand Volcanic Foreland (NW Iran): Arsenic Speciation and Heavy Metal Risk Indicators
    (Academic Press Inc Elsevier Science, 2026) Ghayurdoost, Farhad; Zarghami, Mahdi; Sadeghfam, Sina; Jabraili-Andaryan, Nasser; Nikmaram, Sara; Baba, Alper; Mosaferi, Mohammad
    Due to the toxic nature of arsenic (As) and its elevated concentrations in many water resources, numerous studies have focused on understanding its origin, distribution, and impacts. This study aimed to identify the dominant As species in groundwater of the Sahand Volcanic Foothills, assess water quality indices, and examine heavy metal (HM) concentrations to address rising concerns about groundwater contamination. A total of 21 groundwater samples were collected and analyzed in accordance with world health organization (WHO) guidelines. Although most samples fell within acceptable ranges, several (notably S10, S20, and S21) exhibited elevated levels of total dissolved solids (TDS), electrical conductivity (EC), and HMs, particularly iron (Fe) and As. Hydrochemical assessments using Piper, Gibbs, Stiff, and Schoeller diagrams indicated that geochemical processes resulting from rock dissolution were the main factors controlling groundwater chemistry, with limited influence from anthropogenic pollution. According to the groundwater quality index (GWQI), most samples were categorized as "good" to "excellent," though some areas ranged from "moderate" to "very poor." HM pollution indices revealed that As concentrations exceeded permissible limits. Health risk assessments further showed that both oral and dermal exposure posed significant carcinogenic and non-carcinogenic risks, especially for children. Speciation analysis indicated that arsenate (As V) was the dominant form of As, consistent with oxidizing aquifer conditions, and is less biologically hazardous than arsenite (As III). The study highlights the necessity of continuous groundwater monitoring, effective pollution source management, and implementation of protective regulations to mitigate environmental and health risks in the region.
  • Article
    Nature-Based Solutions in Island Water Management: A Case Study From Bozcaada (Türkiye)
    (Academic Press Ltd- Elsevier Science Ltd, 2025) Samiloglu, Bilgesu; Baba, Alper; Cuevas, Raquel Marijuan; Gunduz, Orhan
    Nature-based Solutions (NbS) are increasingly recognized for their role in the sustainable management of water resources, especially in Mediterranean regions facing seasonal water scarcity. While their benefits for biodiversity and climate resilience are well documented, there is little research on their application in small island regions where ecological fragility and water scarcity intersect. This study fills this gap by investigating the potential of NbS, particularly rainwater harvesting systems, on the island of Bozcaada (T & uuml;rkiye). A high-resolution Digital Elevation Model (DEM) was developed to delineate the watersheds of the island and analyze the water flow patterns. These watersheds were analyzed for their water retention potential and suitability for rainwater storage. The geological structure, soil type and native biodiversity were included in the site selection process to ensure ecological compatibility. Based on this analysis, optimal locations for ponds were identified and designed to support groundwater recharge and preserve local ecosystems. The results show that strategically placed rainwater ponds can improve seasonal water availability, reduce dependence on external sources and support native species throughout the year. This NbS-based approach provides a replicable framework for sustainable water management on small Mediterranean islands, emphasizing ecological integration and long-term resilience.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Evaluating the Impact of Nature-Based Solutions on the Provision of Water-Related and Water-Dependant Ecosystem Services
    (Elsevier Inc., 2024) Marijuan, Raquel; Diez, Barbara; Pelaez-Sanchez, Sara; Iglesias, Jesus; Sirin, Basar; Baba, Alper; Sanchez, Raul
    Water scarcity is a pressing issue in the Mediterranean region, exacerbated by overuse of resources for agriculture and the impacts of climate change. Addressing this challenge requires improved water cycle management and the adoption of Nature-based Solutions (NbS) to enhance infrastructure efficiency and sustainability. With the aim of promoting the implementation and assessment of NbS, we have developed a monitoring framework that integrates the assessment of ecological, socio-economic and cultural aspects under the umbrella of the IUCN Global Standard for NbS. A list of Key Performance Indicators (KPIs) was selected following standard methodologies. We have applied the framework to five case studies in the Mediterranean region to evaluate its efficiency to assess NbS tailored to local challenges and contexts. As part of the monitoring framework, we used the IUCN self-assessment tool for the Global Standard for NbS, demonstrating adherence of 50-75 % across all case studies. Common KPIs were identified, streamlining monitoring efforts and providing guidance from the design phase onwards. Our monitoring framework offers a comprehensive approach to evaluating NbS interventions, ensuring alignment with global standards and enhancing resilience in water management. By integrating the IUCN Global Standard, it provides robust guidance for future execution, contributing to sustainable water resource management in the Mediterranean and beyond.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 4
    Comparison of Conventional and Machine Learning Models for Kinetic Modelling of Biomethane Production From Pretreated Tomato Plant Residues
    (Elsevier, 2025) Fidan, Berrak; Bodur, Fatma-Gamze; Oztep, Gulsh; Gungoren-Madenoglu, Tuelay; Baba, Alper; Kabay, Nalan
    Tomato plant residues (Solanum lycopersicum L.) lack sustainable applications as abundant lignocellulosic biomass after harvest. These residues can be utilized as substrates in anaerobic digestion for biomethane production, generating energy and reducing waste. The purpose of this study was to investigate the sustainable utilization of tomato plant residues for biomethane production at varying conditions and to model biological kinetics. The study aimed to evaluate the effects of varying substrate/inoculum ratios, sulfuric acid pretreatment concentrations, and yeast (Saccharomyces cerevisiae) addition on biogas and biomethane yields under mesophilic conditions (37 degrees C). Maximum biogas and biomethane yields in the studied range were obtained when the substrate/inoculum ratio was 3 (g substrate/g inoculum), the sulfuric acid concentration used for residue pretreatment was 2 %v/v, and the substrate/yeast ratio was 10 (g substrate/g yeast). The yeast ratio of 10 increased the cumulative biogas and biomethane production by 96.5 and 128.9%, respectively. Conventional models (Modified Gompertz, Cone, First-order, Logistic) and Machine Learning models (Support Vector Machine and Neural Network) were compared for biological kinetics. Machine Learning models were also observed to give good fitting results similar to conventional models. Results suggest that Machine Learning models (RMSE: 2.5833-12.0500) are reliable methods like conventional kinetic models (RMSE: 2.1796-13.4880) for forecasting biomethane production in anaerobic digestion processes and Machine Learning models can be applied without needing prior understanding of biomethane production kinetics.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 3
    Evaluation of the Source and Mechanisms of Groundwater Recharge for the Southern Sections of the Western Afar Rift Margin and Associated Rift Floor
    (Elsevier, 2024) Gidafie, Dereje; Nedaw, Dessie; Azagegn, Tilahun; Abebe, Bekele; Baba, Alper
    Study area: Southern Sections of Western Afar rift margin and associated rift floor. Study focus: The purpose of this study is to identify the source and mechanisms of groundwater recharge based on geological, hydrochemical, and environmental isotope studies. New hydrogeological insights: The investigation illustrate that the columnar jointed basalt was extended from the plateau to the rift margin. In addition, transverse structures trending NW-SE and NE-SW connect the plateau to the rift margin and the marginal grabens to the rift floor. The hydrochemical interpretations with EC and TDS shows that the groundwater from the plateau has evolved from Ca-dominated and slightly mineralized to Na-dominated and highly mineralized to the rift floor. Isotopically, the deep groundwater systems are depleted in the entire physiography in contrast to the shallow groundwater systems. Radon measurements are higher at the outlets of the marginal grabens and between the rift margin and the rift floor, suggesting groundwater feeds the river. A comprehensive analysis of the aforementioned results suggests that the deep circulating groundwater is recharged in the plateau and escarpment and chemically altered with increasing depth and along its preferential flow path into the rift floor. Therefore, the plateau area is the main source of recharge for the western Afar rift margin and associated rift floor, due to the presence of preferential pathways, mainly the columnar jointed basalts and crossstructures.
  • Article
    A Methodology Providing New Insights Into the Flow Patterns of Karst Aquifers: an Example From Sw Türkiye
    (Springer Heidelberg, 2024) Maramathas, Athanasios; Katsanou, Konstantina; Sagir, Cagdas; Baba, Alper; Lambrakis, Nikolaos
    This paper presents a new and innovative methodology for the investigation of karst systems using spring discharge. The behaviour of springs in phase space is investigated by plotting the measurements of spring discharge versus the measurements of the water level at the spring's outlet. Such a diagram reveals new features of the function of the karst system and the discharge pattern of the spring that are not captured by common research methods. The application of this method to the Azmak Spring in southwestern T & uuml;rkiye revealed the existence of five distinct discharge subsystems that operate alternately and never simultaneously. They have a specific connection between them, while the transition from one to another is not random but follows a pattern. An attempt was made to interpret these features using concepts from percolation theory.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 6
    A Sustainable Clean Energy Source for Mitigating Co<sub>2</Sub> Emissions: Numerical Simulation of Hamit Granitoid, Central Anatolian Massif
    (Springer Heidelberg, 2024) Ayzit, Tolga; Singh, Mrityunjay; Chandrasekharam, Dornadula; Baba, Alper
    T & uuml;rkiye relies on coal-fired power plants for approximately 18 GW of annual electricity generation, with significantly higher CO2 emissions compared to geothermal power plants. On the other hand, geothermal energy resources, such as Enhanced Geothermal Systems (EGS) and hydrothermal systems, offer low CO2 emissions and baseload power, making them attractive clean energy sources. Radiogenic granitoid, with high heat generation capacity, is a potential and cleaner energy source using EGS. The Anatolian plateau hosts numerous tectonic zones with plutonic rocks containing high concentrations of radioactive elements, such as the Central Anatolian Massif. This study evaluates the power generation capacity of the Hamit granitoid (HG) and presents a thermo-hydraulic-mechanical (THM) model for a closed-loop geothermal well for harnessing heat from this granitoid. A sensitivity analysis based on fluid injection rates and wellbore length emphasizes the importance of fluid resident time for effective heat extraction. Closed-loop systems pose fewer geomechanical risks than fractured systems and can be developed through site selection, system design, and monitoring. Geothermal wellbore casing material must withstand high temperatures, corrosive environments, and should have low thermal conductivity. The HG exhibits the highest heat generation capacity among Anatolian granitoid intrusions and offers potential for sustainable energy development through EGS, thereby reducing CO2 emissions.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 14
    Boron Removal From Geothermal Brine Using Hybrid Reverse Osmosis/Microbial Desalination Cell System
    (Elsevier, 2023) Jarma, Yakubu A.; Kabay, Nalan; Baba, Alper; Ökten, Hatice Eser; Gören, Ayşegül Yağmur
    Agriculture sector leads worldwide as the most water consuming sector with water demand. Since natural water resources cannot keep up with the demand, a shift from conventional water resources to unconventional ones is needed. While geothermal water was gaining importance for its energy content, small-scale (<10 L/s) energy plants were not required to reinject their spent geothermal brine. As geothermal resources align with agricultural areas in Western Anatolia, discharge of untreated brine might have severe adverse effects on crop yields and soil quality. In this study, we investigated use of spent geothermal brine for irrigation after treatment with Reverse Osmosis/Microbial Desalination Cell (RO/MDC) hybrid process. Treatment efficiencies for B, COD, As, Li, Fe, Cr concentrations and energy production values were determined. Treated water was initially evaluated for irrigation considering three quality categories (I, II, and III) comprised of parameters such as electrical conductivity (EC), total dissolved solids (TDS), and sodium adsorption ratio (SAR), along with sodium, chloride and boron concentrations. Additionally, magnesium adsorption ratio (MAR) and permeability index (PI) were used to evaluate for irrigation suitability. Although B concentrations in MDC-treated permeate (3.29 mg/L) and concentrate (2.99 mg/L) streams were not low enough to meet Quality I criterion (<0.7 mg/L), they can be still utilized in irrigation of moderate-to-high tolerant plants. Furthermore, PI and MAR parameters pointed to suitability for irrigational use. © 2022
  • Article
    Citation - WoS: 40
    Citation - Scopus: 47
    Boron in Geothermal Energy: Sources, Environmental Impacts, and Management in Geothermal Fluid
    (Elsevier, 2022) Mott, A.; Baba, Alper; Hadi Mosleh, Mojgan; Ökten, Hatice Eser; Babaei, Masoud; Gören, Ayşegül Yağmur; Feng, C.; Recepoğlu, Yaşar Kemal; Uzelli, Taygun; Uytun, Hüseyin; Morata, Diego; Yüksel Özşen, Aslı
    The problem of hazardous chemicals in geothermal fluid is a critical environmental concern in geothermal energy developments. Boron is among the hazardous contaminants reported to be present at high concentrations in geothermal fluids in various countries. Poor management and inadequate treatment of geothermal fluids can release excessive boron to the environment that has toxic effects on plants, humans, and animals. Despite the importance of boron management in geothermal fluid, limited and fragmented resources exist that provide a comprehensive understanding of its sources, transport and fate, and the treatment strategies in geothermal energy context. This paper presents the first critical review from a systematic and comprehensive review on different aspects of boron in geothermal fluid including its generation, sources, toxicity, ranges and the management approaches and treatment technologies. Our research highlights the origin of boron in geothermal water to be mainly from historical water-rock interactions and magmatic intrusion. Excessive concentrations of boron in geothermal fluids have been reported (over 500 mg/L in some case studies). Our review indicated that possible boron contamination in geothermal sites are mostly due to flawed construction of production/re-injection wells and uncontrolled discharge of geothermal water to surface water. The dominancy of non-ionic H3BO3 species makes the selection of the suitable treatment method for geothermal waters limited. Combining boron selective resins and membrane technologies, hybrid systems have provided effluents suitable for irrigation. However, their high energy consumption and course structure of boron selective resins encourage further research to develop cost-effective and environmentally friendly alternatives.