Civil Engineering / İnşaat Mühendisliği

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  • Article
    Citation - WoS: 2
    Citation - Scopus: 5
    Experimental Modeling of Antimony Sulfides-Rich Geothermal Deposits and Their Solubility in the Presence of Polymeric Antiscalants
    (Elsevier, 2022) Karaburun, Emre; Sözen, Yiğit; Sözen, Yiğit; Şahin, Hasan; Baba, Alper; Baba, Alper; Yeşilnacar, Mehmet İrfan; Şahin, Hasan; Demir, Mustafa Muammer; Demir, Mustafa Muammer; 01. Izmir Institute of Technology; 04.04. Department of Photonics; 03.03. Department of Civil Engineering; 03.09. Department of Materials Science and Engineering; 03. Faculty of Engineering; 04. Faculty of Science
    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 °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.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 6
    Testing the Performance of Various Polymeric Antiscalants for Mitigation of Sb-Rich Precipitates Mimicking Stibnite-Based Geothermal Deposits
    (Hindawi Publishing Corporation, 2020) Çiftçi, Celal; Tonkul, Serhat; Karaburun, Emre; Demir, Mustafa Muammer; Tonkul, Serhat; Baba, Alper; Baba, Alper; Demir, Mustafa Muammer; Yeşilnacar, Mehmet İrfan; 03.06. Department of Energy Systems Engineering; 03.03. Department of Civil Engineering; 03.09. Department of Materials Science and Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
    Scaling is frequently observed in geothermal fields and reduces the energy harvesting of power plants. Recently, Sb-rich deposits have developed in many fields around the world. Various polymeric macromolecules have been used as antiscalants to mitigate the formation of scale. Testing potential commercial antiscalants in field conditions is a tedious and costly process. The artificial synthesis of geothermal deposits in the lab is a more practical and economical way to test the performance of antiscalants. This study obtained a Sb-rich deposit by refluxing SbCl3 and Na2S center dot 3H(2)O in 18 h. The product was found to be a mixture of Sb2O3 and Sb2S3. We examined the performance of antiscalants such as poly(ethylene glycol), poly(vinyl pyrrolidone), Gelatin, and poly(vinyl alcohol) of various molecular weights at 5 to 100 ppm. The formation of Sb2S3 is suppressed in the presence of the polymeric antiscalants. The dosage was found to be critical for the solubilization of Sb-rich deposits. Gelatin of 5 ppm showed the highest performance under the conditions employed in this study. While low dosages improve the concentration of [Sb3+], high dosages are required to increase the solubility of [S2-]. Moreover, the amount of deposit is reduced by 12.4% compared to the reference (in the absence of any polymeric molecules). Thus, comparatively, Gelatin shows the most promising performance among the molecules employed.
  • Article
    Citation - WoS: 40
    Citation - Scopus: 44
    Geological and Hydrogeochemical Properties of Geothermal Systems in the Southeastern Region of Turkey
    (Elsevier Ltd., 2019) Baba, Alper; Şaroğlu, Fuat; Baba, Alper; Özel, Nedret; Yeşilnacar, Mehmet İrfan; Demir, Mustafa Muammer; Demir, Mustafa Muammer; Gökçen Akkurt, Gülden; Uzelli, Taygun; Dursun, N.; Uzelli, Taygun; Yazdani, Hamidreza; 03.03. Department of Civil Engineering; 03.06. Department of Energy Systems Engineering; 01.01. Units Affiliated to the Rectorate; 03.09. Department of Materials Science and Engineering; 01. Izmir Institute of Technology; 03. Faculty of Engineering
    The Anatolia region is one of the most seismically active regions in the world. It has a considerably high level of geothermal energy potential thanks to its geological and tectonic settings. The Southeastern Anatolia Region (GAP) is located in the south of Bitlis-Zagros Suture Zone (BZSZ) which is in the Arabian foreland. During the neotectonic period, the folded structures have been developed under the influence of tectonic compression from the Upper Miocene in the GAP Region where it is closely related to active tectonics. These tectonic activities produce more geothermal resources. Few studies have been carried out in this region for geothermal energy. Limited portions of the geothermal resources have been used both for thermal tourism and greenhouses in the GAP region. The aim of this study is to determine geological, tectonic and hydrogeochemical properties of a geothermal system in the GAP Region. The result indicates that the surface temperatures of geothermal fluids are from 20 to 84.5 °C A large number of abandoned oil wells, whose temperature reaches 140 °C, are found in the region. Also, hydrogeochemical results show that deep circulated geothermal fluids are enriched with Na-Cl and shallow geothermal system fluids have Na−HCO 3 and Ca-SO 4 characters because of cold water mixing and water-rock interaction. Cold waters are generally of Ca-Mg−HCO 3 and Ca−HCO 3 type. Cation geothermometers were used for determining reservoir temperature of the geothermal resources in the region. The results show that the reservoir temperature of these geothermal resources ranges from 50 °C to 200 °C. The isotope data (oxygen-18, deuterium and tritium) suggests that geothermal fluid is formed by local recharge and deep circulation.