Brine clarification at Svartsengi, Iceland; Effect of pH and temperature on the precipitation of silica and its properties

Journal Article · Sat Dec 31 23:00:00 EST 1988 · Geothermics; (USA)

DOI:https://doi.org/10.1016/0375-6505(89)90038-2· OSTI ID:5385474

Thordarson, H ^[1]; Tomasson, T ^[2]

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1. Iceland Univ., Reykjavik (Iceland). Science Inst.
2. Icelandic Technological Institute, Reykjavik (IE)

This report concerns the precipitation of silica in waste geothermal brine from the Svartsengi power plant, Reykjanes Peninsula, Iceland. The aim of the investigation was to obtain general information on the precipitation process and the properties of the silica thus produced. The rate of silica polymerization was measured at various conditions with respect to pH and temperature. The effects of pH, temperature and time (of pH change) on surface area and pore volume were studied. Depending on the conditions a surface area of 20-500 m/sup 2//g and pre volume up to 3 cm/sup 3//g could be obtained. Higher pH and temperature were found to aid the aggregation process. Allowing the polymerization to proceed for some time before increasing pH resulted in faster aggregation and a larger surface area than would have been reached if the pH had been increased at once. Generally, the pore volume was low when the surface area was large and vice versa.

• OSTI ID: 5385474
• Journal Information: Geothermics; (USA), Journal Name: Geothermics; (USA) Vol. 18:1; ISSN GTMCA; ISSN 0375-6505
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
152001* -- Geothermal Data & Theory-- Properties of Aqueous Solutions
BRINES
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
DEVELOPING COUNTRIES
EUROPE
FLUIDS
GEOTHERMAL FLUIDS
ICELAND
ISLANDS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PH VALUE
POLYMERIZATION
SILICA
SILICON COMPOUNDS
SILICON OXIDES
TEMPERATURE EFFECTS
WESTERN EUROPE