Civil Engineering / İnşaat Mühendisliği

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  • Article
    Citation - WoS: 3
    Citation - Scopus: 4
    Geothermal Potential of Manuguru Geothermal Field of Godavari Valley, India
    (Elsevier, 2022) Singh, Hemant K.; Chandrasekharam, Dornadula; Minissale, A.; Raju, N. Janardhana; Baba, Alper
    The Godavari geothermal field in India is one of the potential areas manifested by several geothermal waters and groundwaters. The geothermal waters of the area are near neutral (pH: 6.5–7.3) with surface temperature ranging from 30 to 55 °C while groundwaters are also near neutral (pH: 6.6–7.5) with surface temperature ranging from 24 to 28 °C. The hydrogeochemistry of the geothermal waters suggests that the geothermal waters show a Na-Ca-SO4-HCO3 to a Ca-HCO3 type and groundwaters are of the Ca-HCO3 to Na-Ca-HCO3 type while groundwaters and river waters are of the Ca-Na-SO4 types. The geothermal waters of the study area are enriched in SO42– and Cl–, due to the interaction with the pyrite-bearing Gondwana sediments and granitic gneiss basement rocks. Furthermore, enrichment of Ca2+, Mg2+ and an increased HCO3/Cl ratio in geothermal water is caused by the exchange and/or mixing process that takes place during water-rock interaction at an elevated temperature while ascending to the surface. This type of behavior of water is also observed during the water-rock interaction experiment at 100 °C. Studies on geothermal gas geochemistry suggest the deeper circulation of geothermal waters in the crust and high helium concentration as a thermal gas that can be utilized for commercial purposes. Estimated reservoir temperatures from quartz and Na-K-Ca geothermometry are in the range 110–195 °C. Therefore, the geothermal water of the study area is categorized as a moderate enthalpy geothermal system. Thermal logging in the borewell and depth range from 50 to 1000 m suggest that the geothermal gradient in the Manuguru area ranges from 22.5 to 105.5 °C/km and heat flow ranges from 83 to 388 mW/m2, which is higher than the regional condition. Therefore, 3584 MWe power can be produced by using the Organic Rankine Cycle (ORC) from the Manuguru geothermal area of Godavari valley
  • 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; Akkuş, I.; Özel, Nedret; Yeşilnacar, Mehmet İrfan; Nalbantçılar, Mahmut Tahir; Demir, Mustafa Muammer; Gökçen, Gülden; Arslan, Ş.; Dursun, N.; Uzelli, Taygun; Yazdani, Hamidreza
    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.
  • Article
    Citation - WoS: 35
    Citation - Scopus: 45
    Types of the Scaling in Hyper Saline Geothermal System in Northwest Turkey
    (Elsevier Ltd., 2014) Demir, Mustafa Muammer; Baba, Alper; Atilla, Vedat; İnanlı, Mustafa
    Tuzla is an active geothermal area located in northwestern Turkey, 80km south of the city of Canakkale and 5km from the Aegean Coast. The geothermal brine from this area, which is dominated by NaCl, has a typical temperature of 173°C. Rapid withdrawal of fluid to ambient surface conditions during sampling causes precipitation of various compounds known as scaling. Scaling is one of the important problems in Tuzla geothermal system that reduces the efficiency of the geothermal power plant and causes economical loss. The aim of this study was to determine the type of scaling as a first step towards preventing its formation. The scales formed in the geothermal system were divided into two groups according to location: the ones that formed in downhole and the ones that accumulated along the surface pipeline. Both scales were examined in terms of their elemental composition, structure and morphology using XRF, XRD, and SEM, respectively. The former was found to be mainly composed of PbS (Galena) and CaCO3 (aragonite or calcite). In contrast, the latter was heterogeneous in nature and consisted of mainly saponite like amorphous structure along with submicrometer-sized amorphous silica particles, layered double magnesium and iron hydroxide, and NaCl.