Characterization of geothermal scale deposits by Fe-57 Moessbauer spectroscopy and complementary x-ray diffraction and infra-red studies

Journal Article · Mon Dec 31 23:00:00 EST 1990 · Geothermics (International Journal of Geothermal Research and its Applications); (United States)

DOI:https://doi.org/10.1016/0375-6505(91)90033-R· OSTI ID:7117309

Gallup, D L ^[1]; Reiff, W M ^[2]

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1. Unocal Corp., Science and Technology Div., Brea, CA (US)
2. Dept. of Chemistry, Northeastern Univ., Boston, MA (US)

Scales deposited form Salton Sea, California and Tiwi, Philippines geothermal brines have been analyzed by Fe-57 Mossbauer spectroscopy. Supporting analyses employing X-ray diffraction and infra-red spectroscopy have also been obtained. Mossbauer analyses of the scales detect the presence of six-coordinate, high spin ferric and ferrous iron believed to be present as hydrous silicates resembling the mineral hisingerite. Highly-ordered oxide backgrounds, attributable to corrosion products, as also detected in the scale samples employing this spectral technique. Ferric-rich silicates and corrosion products are commonly observed in scales deposited from acidified brines at high temperature. Ferrous-rich silicates are predominant in scales deposited at low temperature. Mossbauer spectroscopy has proven useful in distinguishing between and quantifying true scale precipitates and poorly crystalline corrosion products. In this paper, Mossbauer analyses are reported for twenty iron mineral phases common to geothermal scale deposits.

• OSTI ID: 7117309
• Journal Information: Geothermics (International Journal of Geothermal Research and its Applications); (United States), Journal Name: Geothermics (International Journal of Geothermal Research and its Applications); (United States) Vol. 20:5; ISSN GTMCA; ISSN 0375-6505
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150903* -- Geothermal Engineering-- Corrosion
Scaling & Materials Development
ASIA
BRINES
CALIFORNIA
CHEMICAL REACTIONS
COHERENT SCATTERING
CORROSION
DEVELOPED COUNTRIES
DEVELOPING COUNTRIES
DIFFRACTION
ELEMENTS
FLUIDS
GEOTHERMAL FLUIDS
GEOTHERMAL SYSTEMS
IRON
ISLANDS
METALS
NORTH AMERICA
OXYGEN COMPOUNDS
PHILIPPINES
SCALING
SCATTERING
SILICATES
SILICON COMPOUNDS
SPECTROSCOPY
TRANSITION ELEMENTS
USA
X-RAY DIFFRACTION