Computer modelling of geothermal brines from the Salton Sea Geothermal Field, California

Conference · Wed Dec 01 04:00:00 EST 1976 · EOS, Trans., Am. Geophys. Union; (United States)

OSTI ID:5384339

Jackson, D; Piwinskii, A J; Miller, D

To produce electric power from energy stored in the hypersaline brines of the Salton Sea Geothermal Field, methods must be developed for controlling the sulfides and silicates which precipitate as scale deposits on process equipment. To circumvent costly, time-consuming, and potentially difficult laboratory experiments, equilibria were predicted in these brines by two different computational techniques, the Helgeson-Herrick code and individual reaction calculations using effective activity coefficients which take into account chloride complexing. The results of both methods are consistent with one another in predicting precipitation behavior in the temperature interval 100 to 300/sup 0/C. For example, results for the Magmamax No. 1 brines indicate that quartz, pyrrhotite, galena, chalcopyrite, sphalerite, and Fe-silicates can precipitate. This predicted sulfide-silicate assemblage agrees generally with observations on scale from the field test site, although the silica-silicate scale matrix is amorphous. Carbonate equilibria are especially interesting; large Ca/sup +2/ and CO/sub 2/ concentrations in the Magmamax No. 1 brine suggest that the reservoir fluid is saturated with respect to calcite. At a downhole temperature of 260/sup 0/C using the calcite curve as a guide, saturation would occur at pH of 3.5 to 4.0.

• Research Organization: Univ. of California, Livermore
• OSTI ID: 5384339
• Conference Information: Journal Name: EOS, Trans., Am. Geophys. Union; (United States) Journal Volume: 57:12
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150903* -- Geothermal Engineering-- Corrosion
Scaling & Materials Development
ALKALINE EARTH METAL COMPOUNDS
BRINES
CALCITE
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CALIFORNIA
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBONATES
CHALCOGENIDES
CHALCOPYRITE
CHEMICAL PROPERTIES
CHEMICAL REACTIONS
COMPUTER CALCULATIONS
COPPER COMPOUNDS
COPPER SULFIDES
CORROSION
EQUILIBRIUM
FLUIDS
GALENA
GEOTHERMAL FIELDS
GEOTHERMAL FLUIDS
IRON COMPOUNDS
IRON SULFIDES
LEAD COMPOUNDS
LEAD SULFIDES
MATHEMATICAL MODELS
MINERALS
NORTH AMERICA
OXIDES
OXYGEN COMPOUNDS
PH VALUE
PRECIPITATION
PYRRHOTITE
QUARTZ
SALTON SEA GEOTHERMAL FIELD
SCALING
SEPARATION PROCESSES
SILICA
SILICATES
SILICON COMPOUNDS
SILICON OXIDES
SPHALERITE
SULFIDES
SULFUR COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
USA