Browsing by Author "Baba, Alper"

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Citation Count: 1
Characterization of Sb scaling and fluids in saline geothermal power plants: A case study for Germencik Region (Buyuk Menderes Graben, Turkey)
(Pergamon-elsevier Science Ltd, 2021) Tonkul, Serhat; Baba, Alper; Demir, Mustafa M.; Regenspurg, Simona; Demir, Mustafa
Turkey is located on the seismically active Alpine-Himalayan belt. Although tectonic activity causes seismicity in the Anatolian plate, it also constitutes an important geothermal energy resource. Today, geothermal energy production is heavily concentrated in Turkey's Western Anatolia region. Graben systems in this region are very suitable for geothermal resources. The Buyuk Menderes Graben (BMG) is an area of complex geology with active tectonics and high geothermal potential power. Germencik (Aydin) is located in the BMG, where the geothermal waters include mainly Na-Cl-HCO3 water types. This study examined the stibnite scaling formed in the preheater system of the Germencik Geothermal Field (GGF). The formation of the stibnite scaling on the preheater system dramatically reduces the energy harvesting of the GGF. Considering the stibnite scaling in the surface equipment, the optimum reinjection temperature was determined as 95 degrees C to prevent stibnite scaling in the GGF.
Citation Count: 11
Design of Polymeric Antiscalants Based on Functional Vinyl Monomers for (Fe, Mg) Silicates
(Amer Chemical Soc, 2017) Topcu, Gokhan; Celik, Asli; Baba, Alper; Demir, Mustafa M.; Demir, Mustafa
Silica/silicate scaling is one of a few detrimental problems that cause high economical loss in the geothermal and petroleum fields. The prevention of silica/silicate has been attempted using antiscalants with functional groups, particularly -NH2; however, metal silicates are commonly found in the fields, and the antiscalants developed thus far are not effective against these compounds. In this work, polymeric antiscalants have been developed by merging two or-snore functional-comonomers consisting of various chelating groups for metal cations. Homo- and copolymers of acrylamide (AM), the sodium salt of vinyl sulfonic acid (VSA), and vinyl phosphonic acid (VPA) were synthesized to examine their antiscaling performance against metal silicate scaling. Lab-scale metal silicates were obtained in a pressured autoclave reactor. The, antiscalants were tested at various dosages (25, 50, and 100 ppm), and their effects were investigated from the leftover decaritates after isolation of the solid precipitates. The polymeric antiscalants were found to be particularly effective against metal silicates and ineffective against simple silica precipitates. Acidic groups may be coordinating the metal cations, which prevents the-formation of precipitates. Among these acidic comonomers; VSA-containing polymers, in particular, increased the solubility-of metal silicates.
Development of a new antiscalant for minimization of stibnite scaling in geothermal binary plants
(01. Izmir Institute of Technology, 2021-03) Karaburun, Emre Mustafa; Demir, Mustafa; Demir, Mustafa Muammer; Baba, Alper; 01. Izmir Institute of Technology
Demand for renewable and sustainable energy resources has been increasing in recent years due to the adverse effects of fossil energy resources (gases, oil, coal ect,) on human health and nature. Since geology properties of our country is rich in geothermal energy resources, there is a remarkable increase in plant capacities every year. Geothermal energy is the energy obtained from the fluid, gas, and steam that have been stored in reservoirs by carrying the heat energy accumulated in the rocks in the depths of the earth or surfaced along the discontinuity zones.The increase in the use of geothermal energy and the increase in the capacity of the power plants has also revealed the problem of scaling. The main cause of deposition are the decrease in solubility of minerals by a decrease in pressure and temperature upon pumping the geothermal brine up to the ground. Calcium carbonate, calcium sulphate, metal silicates (Mg, Fe) are the most widely accepted types of scaling. In recent years, antimony and arsenic sulfide scaling have been encountered in volcanic and metamorphic regions. Between these two types of scaling, antimony sulfide is mostly seen in the heat-exchangers and preheaters where the temperature drops suddenly. In this thesis, the antimony sulfide scaling formed in the geothermal power plant was synthesized in an autoclave reactor under specified conditions. Water-soluble polymers nominee for being antiscalants such as Poly (vinyl sulfonic acid), Poly (acrylamide-co-vinyl sulfonic acid), Poly (acrylamide-co-vinyl phosphonic acid), Alginic Acid, Natural antiscalants, Polyacrylic acid, and Polyvinyl alcohol were employed. The results suggest that polymers containing vinyl sulfonic acid and acrylamide likely shows remarkable progress in increasing the concentration of ions in decantate, particularly at low dosages. (≈5 ppm)
Effect of high saline geothermal fluid on soil and surface water: A case study from Tuzla, Çanakkale-Turkey
(Izmir Institute of Technology, 2013) Katırcıoğlu, Gamze; Baba, Alper
Geothermal energy can be defined as a heat from core of Earth and utilized for power generation, district heating and greenhouse. Use of geothermal energy has low environmental impact, particularly when compared with fossil fuels. However, geothermal fluid has some adverse effects for environment for instance contamination of surface water and soil. Examples of these effects occur in different parts of world. The objective of this study is to evaluate the effect of geothermal fluid particularly on surface water and soil in Tuzla Geothermal Field (TGF) where is located on Biga Peninsula, in the northwestern of Anatolia. TGF is 5 km far from Aegean Sea and 80 km south of Çanakkale. Geothermal fluid of TGF has high salinity (EC > 91 mS/cm) and high temperature (reservoir temperature is 173 Â°C). Water samples were taken from February 2012 to April 2013 to determine the physical and chemical (major anioncations and heavy metals) properties of the surface water quality. Furthermore, the soil samples analyzed for physical and chemical properties. All data were evaluated with ArcGIS 10.1 and Aquachem 4.0 software. The results showed that the levels of some major element such as Lityum (4-7 ppm), Barium (1-4 ppm) and Manganese (1-5 ppm) and some heavy metals such as Boron (> 13 ppm) and Strontium (> 14 ppm) in surface water, exceeded national and international limits. Boron and Strontium values of creek ranged from 13 to 27 ppm and from 14 to 154 ppm, respectively. Soil samples contain high concentration of Silisium (> 23800 mg/kg) and Aluminum (> 9000 mg/kg). Particularly, the uncontrolled discharge of geothermal fluid that is rich in terms of toxic elements into soil and surface water resources of the area influences other potential uses of these resources.
Citation Count: 1
Effect of high salinity and temperature on water-volcanic rock interaction
(Springer, 2021) Goren, A. Yagmur; Topcu, Gokhan; Demir, Mustafa M.; Baba, Alper; Demir, Mustafa
In order to understand the processes occurring in natural hydrothermal systems, it was carried out a series of water-volcanic rock interaction studies in the laboratory and an intermediate volcanic rock samples from geothermal production wells in Tuzla geothermal field (TGF) in western Turkey. A high-pressure autoclave was used to conduct water-rock interaction experiments under similar conditions of the field. Rainwater and seawater were treated with volcanic rocks at 140 degrees C (reservoir temperature) and 4.5 bar pressure. The change in the ionic content of the resulting fluids was examined in terms of the type of volcanic rocks and mineral saturation index. The results indicate that talc and diopside minerals in geothermal systems may cause scaling at high temperatures depending on the geothermal fluid and pH.
Citation Count: 1
Experimental modeling of antimony sulfides-rich geothermal deposits and their solubility in the presence of polymeric antiscalants
(Pergamon-elsevier Science Ltd, 2022) Karaburun, Emre; Sozen, Yigit; Ciftci, Celal; Sahin, Hasan; Baba, Alper; Akbey, Umit; Demir, Mustafa M.; Demir, Mustafa
Antimony (Sb)-rich geothermal deposits have been observed in many geothermal power plants worldwide. They occur as red-colored, sulfidic precipitates disturbing energy-harvesting by clogging the geothermal installations. In order to prevent the formation of this scale, information on its physicochemical features is needed. For this purpose, Sb-rich sulfide-based deposits were synthesized at controlled conditions in a pressurized glass reactor at geothermal conditions (135 degrees C and 3.5 bar). Various polymeric antiscalants with different functional groups, such as acrylic acid, sulphonic acid, and phosphonic acid groups were tested for their effect on Sb sulfide solubility. An additional computational study was performed to determine the binding energy of Sb and S atoms to these groups. The results suggest that sulfonic acid groups are the most affective. Therefore, it was concluded that these macromolecule containing sulfonic acid groups and poly (vinyl sulfonic acid) derivatives could potentially act as antiscalants for the formation of antimony sulfide.
Citation Count: 10
Experimental modeling of silicate-based geothermal deposits
(Pergamon-elsevier Science Ltd, 2017) Celik, Ash; Topcu, Gokhan; Baba, Alper; Akdogan, Yasar; Senturk, Ufuk; Demir, Mustafa M.; Demir, Mustafa
Scaling by metal silicates represents a major obstacle for geothermal systems. A composition that enables the fabrication of artificial deposits is necessary for the rapid testing of potential inhibitors. In this work, artificial deposits were synthesized by employing experimental conditions similar to those in the Tuzla Geothermal Field in Turkey. Although refluxing enabled the formation of a precipitate that was similar to naturally formed deposits in color and texture, their elemental composition and morphology showed a mismatch. An autoclave enabled the production of a precipitate that more closely resembled naturally formed deposits in color, texture, elemental composition, and structure.
HEC HMS hydrological model application using SCS Curve Number and Soil Moisture Accounting: Case study of Alaşehir Basin
(Izmir Institute of Technology, 2019-06) Akdeğirmen, Özgün; Baba, Alper; Tayfur, Gökmen
Water is known as source of life throughout mankind’s history. According to first records of written history; Sumerians and Akkadians used water for their inland transportation and irrigation systems. With first settlements, mankind’s dependency to water has been increased and became one of the most substantial natural resource in our modern age. Importance of this resource even more solidifies when we consider its property of being limited. With realization of global climate change in early 19th century; treat to this limited resource has been revealed. Approximately 68% of the freshwater on earth reserved in glaciers and icecaps and 30% is reserved in groundwater systems according to United States Geological Survey’s (USGS) studies. Owing to the quantity and less compromised to contaminants nature, majority of our freshwater needs met from groundwater. Although the importance of groundwater, its management have always been a challenge due to hard to quantify volumetric changings in aquifers. This study focused on creating a hydrological basin model to investigate volumetric recharge changings in groundwater system. Under scope of this study in an attempt to acquire groundwater recharge amounts; practicality of HEC-HMS hydrological modeling software has been investigated. A SCS Curve Number and Soil Moisture Accounting (SMA) loss methods has been chosen for HEC-HMS modeling application due to availability and accessibility of data that required for loss methods. After data collection from meteorological stations, core drill samples; both methods have been used in HEC-HMS simulation environment and their predictions have been compared. In the comparisons, it was determined that the SCS Curve Number method predicts higher flow potentials and groundwater infiltration amounts compared to the SMA method. Models foresee an average of 33.4 % of precipitation infiltrates into groundwater system.
Citation Count: 20
Hydrogeological properties of hyper-saline geothermal brine and application of inhibiting siliceous scale via pH modification
(Pergamon-elsevier Science Ltd, 2015) Baba, Alper; Demir, Mustafa M.; Koc, Gonca A.; Tugcu, Celal; Demir, Mustafa
Scaling is a major obstacle in harnessing of geothermal energy from the geothermal resources. This paper presents a case study for inhibition of metal silicate scaling using formic acid, harvesting more energy in particular case of Tuzla Geothermal Field (TGF), located on Biga Peninsula, in the northwestern of Turkey. TGF is 5 km far from Aegean Sea and 80 km south of Canakkale. Geothermal fluid of TGF has high salinity (EC > 91 mS/cm) and medium temperature (reservoir temperature is 173 degrees C). The acidification of high-salinity brine to mitigate silicate scaling is examined. Results of the study showed that a compromise between scaling and corrosion is achieved by reducing pH of brine to <6 using 55 ppm formic acid. (C) 2014 Elsevier Ltd. All rights reserved.
Citation Count: 5
Hydrogeology and hydrogeochemistry of the geothermal systems and its direct use application: Balcova-Narl?dere geothermal system, Izmir, Turkey
(Pergamon-elsevier Science Ltd, 2022) Baba, Alper; Sozbilir, Hasan; Sayik, Tolga; Arslan, Sinan; Uzelli, Taygun; Tonkul, Serhat; Demir, Mustafa M.; Demir, Mustafa
The Balcova-Narlidere geothermal system, located in western Turkey, is an extensional domain type geothermal play. Geological, hydrogeological, and geothermal studies have been done in the Balcova-Narlidere geothermal field since 1960. As a result of these studies, production and research wells were drilled in the area by both the public and private sectors. Of the 37 wells drilled in the Balcova-Narlidere geothermal field, 26 were drilled by Izmir Geothermal Energy Company Inc. (16 productions, 4 re-injection, 4 gradientst, 2 unused) and 11 by the Izmir Governorship Investment Monitoring and Coordination Department and companies in the private sectors. There are two reservoirs, one shallow and one deep, in the geothermal field. Well depths are less than 200 m in the shallow reservoir. The deep production wells have depths ranging from 400 to 1,100 m and reservoir temperatures reaching 140 degrees C. The electrical conductivity (EC) values in the shallow production wells range from 1,200 to 1,500 mu S/cm. EC values in the deep production wells vary from 1,871 to 2,025 mu S/cm, and all geothermal fluids in the field are mineral-rich waters. In the Izmir geothermal district heating system, the newest technologies are used, and operational costs are very low. Izmir Geothermal Energy Company Inc. has been operating since 1996 and has reached 38,460 residences. The current capacity of the system is approximately 160 MWt. Cooling systems continue to spread in Turkey, focusing on electric air conditioning systems and geothermal heating systems, but both economic and applicability problems have slowed the expansion of cooling systems. However, Izmir Geothermal Energy Company Inc. began operating its first geothermal cooling application in Balcova in 2018, cooling 1,900 m2 of the indoor area by lithium bromide absorption and 90/85 degrees C geothermal temperature regime by supplying 6/9 degrees C clean cold water to the coolers in the buildings. These results show that the extensional domain type geothermal system in the Balcova-Narlidere region is suitable for both heating and cooling applications.
Impact of urbanization on hydrogeodynamic systems: A case study: Bornova region (İzmir, Turkey)
(01. Izmir Institute of Technology, 2021-12) Öztürk, Bahadır; Baba, Alper; İşbuğa, Volkan; 01. Izmir Institute of Technology
Urbanization is one of the most critical processes affecting land and water use. Understanding urbanization and its impact on ground systems gained prominence with global climate change and population increase. This study focuses on the new city center Bornova Plain, İzmir; Turkey, used as agricultural land until the 1950s. Later, the region was opened for settlement, and excessive urbanization decreased the hydraulic conductivity of the surface area of the plain with the constructed buildings, road pavements, and other surface coverings. Effects of the land use- land cover changes on the hydrodynamic system of Bornova Plain's aquifers were investigated in three parts. Firstly, GIS-based hydrological models with two different periods (2004 and 2020) scenarios were developed with ArcSWAT for this thesis. Using SWAT models, elements of the water budget equation were determined. With SWAT Models, Recharge/Precipitation, Streamflow/Precipitation, and Baseflow/Total flow ratios were found to decrease 52%, 26.09%, and 11.86%, respectively, and Surface Runoff/Total Flow, and ET/Precipitation ratios were found to increase 20.59%, and 15.09% with urbanization increment comparing 2004 and 2020. Secondly, soil's bearing capacity changes with groundwater level changes within a year were investigated using five observation wells. Conceptual models were created for each well. Maximum of 14.82% of bearing capacity change was observed in the wells. Thirdly, PLAXIS 3D models were created to understand the effect of the groundwater level changes on pile settlements for sandy and clayey soils in the region. Conceptual models created and maximum of 12.74% settlement difference was observed for different groundwater levels.
Citation Count: 15
Increasing solubility of metal silicates by mixed polymeric antiscalants
(Pergamon-elsevier Science Ltd, 2019) Topcu, Gokhan; Celik, Asli; Kandemir, Ali; Baba, Alper; Sahin, Hasan; Demir, Mustafa M.; Demir, Mustafa
The increase of silicate solubility is a big challenge for both hot and cold water because it reduces the deposition of metal silicates frequently observed in such systems and causes operational obstacles. The deposition of silicate coats the inner surface of the pipelines in an uncontrolled manner and reduces the harvesting of energy from brines. In this work, the solubility performance of two commercial water-soluble polymeric agents (poly(ethylene glycol) (PEG) and poly(vinyl alcohol) (PVA)) of various molecular weights employing dosage from 25 to 100 mg/L was examined. Along with dispersant-type antiscalant, poly(acrylamide) (PAM), poly(vinylsulfonic acid, sodium salt) (PVSA), and poly(vinylphosphonic acid) (PVPA) having chelating acidic groups were employed. Metal silicate deposits were obtained artificially in the lab-scale pressurized reactor. The experimental conditions employed were quite similar to a model power plant located in canaldcale, Turkey. The concentration of dissolved silica was increased from 130 to 420 mg/L when 100 mg/L PEG 1500 and 25 mg/L PVSA were employed as a mixture. For the atomic-level understanding of the interaction of chelating groups with metal cations, DFT calculations were performed too.
Citation Count: 11
The injection of CO₂ to hypersaline geothermal brine: A case study for Tuzla region
(Pergamon-elsevier Science Ltd, 2019) Topcu, Gokhan; Koc, Gonca A.; Baba, Alper; Demir, Mustafa M.; Demir, Mustafa
Scaling is a serious issue for geothermal power plants since it remarkably decreases the harvesting of energy. The reduction of pH by organic acids whose structure is close to CO2 for instance formic acid has been an effective solution for the minimization of scaling. Herein, the effect of CO2 injection on the formation of scaling particularly metal-silicates was investigated for the model case of Tuzla Geothermal Field (TGF) located in the northwest of Turkey. CO2 has an acidic character in aqueous systems because it leads to the formation of carbonic acid. The injection of 20.6 m(3)/s CO2 (approximately 88 ppm) to hypersaline brine of TGF is a promising green approach for both mitigation of scaling by reducing pH from 7.2 to 6.2 at the well-head and the minimization of potential corrosion compared to the use of formic acid (55 ppm).
Investigation of bioelectrochemical treatment efficiency for removal of boron from geothermal waters
(Izmir Institute of Technology, 2022-07) Gören, Ayşegül Yağmur; Ökten, Hatice Eser; Baba, Alper
Microbial desalination cell (MDC) is a promising technology due to its simultaneous features of electricity production, wastewater treatment, and desalination. In this thesis, boron (B) removal from geothermal water and organic matter removal from yeast wastewater with energy production was studied using a three chamber (anode/desalination/cathode) lab-scale MDC system. Among operational conditions, electrode surface area was proven to be significant on B removal efficiency. Then, anode chamber of the conventional MDC was modified to include three-dimensional (3D) cubic electrodes as a novel design. B and organic matter removal efficiencies and the produced power density results were promising for 3D-electrodes. Further studies in order to increase the efficiency of MDC system was conducted by synthesizing 3D hybrid sponge electrodes with activated carbon-chitosan (AC-CS). MDC with 3D AC-CS anode provided a higher power density of 970 mW/m2 , B removal efficiency of 75.9%, and COD removal efficiency of >90% under optimized conditions. Furthermore, phytoremediation performance of Lemna minor L. on B removal was found to be 96.7 %. Also, removal of B and heavy metals from reverse osmosis (RO) permeate and concentrate streams using RO-MDC hybrid process was studied. The performance of ROMDC system was proven to be significant on B and heavy metals removal efficiency. Lastly, feasibility of B removal from geothermal water using MDC-Donnan dialysis hybrid process was evaluated. The most important output of this study was decreased frequency for pH adjustment. Overall, MDC, being in its early levels of technology readiness, produced promising desalination and energy production results in removal of boron from geothermal brine.
The investigation of seawater intrusion of coastal aquifer in Karareis (Karaburun Peninsula)
(Izmir Institute of Technology, 2016-11) Mansour, Ahmed Y. S.; Baba, Alper; Gündüz, Orhan
Seawater intrusion is a major problem to freshwater resources especially in coastal areas where fresh groundwater is surrounded and could easily be influenced by seawater. This study presents the development of conceptual and numerical model for the coastal aquifer of Karareis region in the western part of Turkey. The study also presents the interpretation and the analysis of the groundwater levels recorded by groundwater data loggers. Groundwater pumping from Karareis aquifer has increased significantly during the summer period to meet the agriculture and domestic water demands. Levels of groundwater were measured at nine locations in Karareis region; also water samples were collected and analyzed for some parameters. For this study SEAWAT code is used to solve the numerical model for the coupled density dependent flow system. The model was calibrated using the average of one-year dataset of collected groundwater levels. Model validation was handled using the average of groundwater levels measured over more one year. Five scenarios were tested to understand the effects of pumping and climate change on groundwater levels and seawater intrusion in the next ten years. The result of analysis demonstrated a high concentration of electrical conductivity and chloride along the coastal part of the study area. As a result of the numerical model, seawater intrusion will extent about 420 m towards the land in the next ten years of increased pumping scenario, while a little change in water level and TDS concentration was recognized in climate change scenario. Results also showed that reducing the pumping from Karareis wells will be necessary to protect the freshwater from contamination by seawater.
Kinetics of silica polymerization at various conditions
(01. Izmir Institute of Technology, 2022-03) Hasköylü Toker, Öykü Çağ; Demir, Mustafa; Demir, Mustafa Muammer; Baba, Alper
Silica is the most abundant element on Earth because the Earth's crust is composed mainly of metal silicates. The source of this silica is mainly volcanic rocks, which come to the surface through tectonic activity and are the primary source of heat for geothermal activity. The silica concentration in a geothermal fluid is higher than the solubility limit of natural waters, so scaling of (metal) silicates is often observed in geothermal operations. This situation has become critical for geothermal power plants. Since silicates have an insulating structure, they lead to a reduction in energy efficiency during fluid transport. The formation of silica-rich deposits should be understood to minimize the negative effects of the scaling. Briefly, silicic acid molecules in the reservoir system are condensed, and the monomeric silicic acid molecules bind to each other via covalent bonds. In the course of this reaction, dimers, tetramers and short oligomers are formed, and eventually a large polymeric silica network is formed. In the presence of metals, both the kinetics of polymerization and the structure of the network are inevitably affected. In this study, the presence of kinetic parameters (different salts such as FeCl3, MgCl2, AlCl3 and NaCl), the reaction process, the rate and the activation energy of silica polymerization at different temperatures between 25 and 90 °C were investigated. The yellow silicomolybdate method was used to determine the concentration of monomeric silica. The order of the polymerization reaction was given as 3. The polymerization occurs in the initial phase, in the first 40 minutes, where the activation energy was about 29.52 ± 2.28 kJ/mol and the rate constant was of the order of 4x10-8 mol-2∙L2∙s-1. The results also confirmed that pH has a stronger effect on the kinetics of silica polymerization than temperature. The neutral solution decreases rapidly, while the acidic solution has an induction phase in the first hour of polymerization. Different temperatures did not affect the polymerization rate as much as pH. At 25°C the experiment showed the fastest polymerization, but at 90°C the low concentration changed from the beginning. During all these experiments, no scaling of amorphous silica was observed, only the polymerization of silica.
Lithium extraction from geothermal brine by adsorption method with electrolytic y-MnO2 sorbent
(Izmir Institute of Technology, 2022-07) Toprak, Seyra; Demir, Mustafa; Demir, Mustafa Muammer; Baba, Alper
In recent years, studies on the recovery of lithium metal have attracted great attention due to its wide application areas, especially in lithium-ion batteries. Recovery of lithium from brines is preferred considering the environmental impacts in mining. The application of manganese oxide sorbents to recover lithium from geothermal brines has been extensively studied as it is a potential source of lithium. In this thesis, adsorption was performed in Tuzla Geothermal Power Plant (TGPP) at 87 °C and 2 bar using a mini-pilot system in the reactor near the reinjection well of the plant to investigate the adsorption performance in field conditions. As a new approach, electrolytic manganese dioxide (γ-MnO2), which is widely used as cathode material in batteries, was used as the sorbent material for lithium and its adsorption/desorption performance was investigated. Batch adsorption experiments were performed in synthetic lithium solution and the optimum working conditions were determined as pH 12, adsorbent concentration of 3 g/L, and initial lithium-ion concentration of 200 mg/L. The highest adsorption capacity of the sorbent in the Langmuir model was found as 9.74 mg/g. The maximum adsorption performance was obtained at 1h adsorption in Tuzla GPP. In the continuation of the study, desorption was carried out in acidic medium with the brine-treated sorbent. Lithium concentration was enriched to around 250 ppm with repetitive desorption studies. Reusability of the sorbent was investigated and the reused sorbent showed almost 40% performance compared to virgin powder. γ-MnO2 was found as a promising sorbent for the separation of lithium from geothermal brines.
Natural groundwater recharge in the Alaşehir sub-basin (Gediz basin, Turkey)
(Izmir Institute of Technology, 2018-12-22) Tonkul, Serhat; Baba, Alper; Şimşek, Celalettin
The increase in water utilization due to climate change in recent years, as well as excessively growing population causes to an increase in usage of groundwater and threatens water resources. Dams and artificial lakes are being constructed to ensure the sustainability of water resources, but there is much evaporation on large surface of these structures. Due to reason that the evaporation losses are not experienced, the groundwater recharge by direct rainfall becomes important. Groundwater recharge protects the water without too much evaporation in the basins and increases the potential of water resources and ensures sustainability. The aim of this study is to determine alluvial aquifer recharge in Alaşehir (Manisa) sub-basin using numerical and chemical methods. In addition to this aim, the mechanism of mixing of groundwater and geothermal fluid has also been examined. The Gediz Basin, located in the west of Turkey constitutes 2% of the country, has an important groundwater potential in the area where it is used. The Alasehir sub-basin, located in the southeast of the Gediz Basin and having extensive withdrawal for irrigation, constitutes the study area. Alluvial aquifer is the main groundwater bearing lithological unit in the plain. Twenty-five research wells, which is ranging from 20 m to 50 m in depth, were opened for the calculation of the recharge of the aquifer. Soil characterization was done on the core samples and the aquifer characterization was performed and the alluvial aquifer recharge was calculated. As a result, the recharge value of annual precipitation is range from 21.78 mm to 68.52 mm and average recharge from precipitation is 43.09 mm in the wells which are opened into the alluvium aquifer. According to the numerical model, this amount of recharge corresponds to 10% of the amount of annual rainfall. This estimated recharge ratio directly represents recharge from precipitation into the aquifer. According to the results of the chemical method, it is understood that the average recharge value from precipitation is 16.38%. In addition, the mixing ratio of the groundwater and geothermal fluid is 17% in the sub-basin. Keywords Aquifer Characterization, Alaşehir, Precipitation Recharge, Numerical Modelling
Citation Count: 2
Scaling problem of the geothermal system in Turkey
(Crc Press-taylor & Francis Group, 2014) Dogan, Irmak; Demir, Mustafa M.; Baba, Alper; Demir, Mustafa
[No Abstract Available]
Surface water quality modeling for best management practices - a case study from Bakırçay River Basin
(01. Izmir Institute of Technology, 2021-07) Kazancı, Yiğithan; Baba, Alper; Gündüz, Orhan; 01. Izmir Institute of Technology
This study was carried out to analyze the water quality in the Bakırçay River basin, which is known to be exposed to intense industrial and agricultural pollutant loads. A mathematical model system called AQUATOOL was used to reveal the changes that the effects of anthropogenic and natural events in the basin will cause on the conservative water quality parameters and nutrients. Model results are given in wet (April) and dry (September) periods for 4 points determined from upstream to downstream in the basin on a spatial basis, and temporal evaluation is also given for 1 upstream river water body, 1 downstream river water body, and 1 lake water body. Seven best management practices scenarios were determined and implemented one after the other in the model. Spatially, the results reveal good water status for both the dry period and the wet period at the upstream points, while at the downstream points, all parameters except BOD5 and Dissolved Oxygen are found to be in poor condition. Besides, similar situations arise in spatial-based results, and despite the scenarios, parameters could not reach good water status except for the lake waterbodies. The improvement in lake results occurs due to dilution, not scenarios. With this study, the pollution load in Bakırçay River Basin and the effects it creates once again revealed that if the anthropogenic loads are not reduced, the water quality of the basin will reach irreversible points for many years. It is thought that this study can constitute a source document for decision-makers, especially in terms of efficiency comparisons in the best management scenarios to be applied.