Types of scaling occurring by geothermal utilization in Iceland

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Geothermics; (USA)

DOI:https://doi.org/10.1016/0375-6505(89)90026-6· OSTI ID:5322943

Kristmannsdottir, H ^[1]

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1. Orkustofnun, Grensasvegur 9, Reykjavik (IE)

The low-temperature geothermal fields in Iceland are mostly used for space heating. Scaling problems have only occurred in a few cases during exploitation. The most severe cases are due to precipitation of calcium carbonate in brackish water and occur both in downhole pumps and surface installations. In plants heating fresh water scaling by magnesium silicate has occurred. In the high-temperature geothermal fields calcium carbonate precipitation in wells is not uncommon but occurs at shallow levels and is amended by reaming the wells at regular intervals. Silica scaling in waste water is a general problem in most of the fields, but is mostly avoided inside the plants and in the distribution piping. Aluminium-silicates have been troublesome where the high-temperature waters have been used directly for heating as they are precipitated at temperatures well above saturation with opaline silica at which point the onset of scaling was expected. From the brine in the Reykjanes field there have been encountered downhole scales of iron-magnesium-silicates, and metalsulfide with high contents of precious metals is precipitated at the wellhead of one of the wells, Rn-9. Iron-silicates were precipitated from the magnetic influenced geothermal fluid in the Krafla field and metallic sulfides and oxides were also present in the scales blocking the wells at that time.

• OSTI ID: 5322943
• 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
150800 -- Geothermal Power Plants
150903* -- Geothermal Engineering-- Corrosion
Scaling & Materials Development
151000 -- Geothermal Energy-- Direct Energy Utilization
152002 -- Geothermal Data & Theory-- Properties of Minerals & Rocks
ALKALINE EARTH METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ALUMINIUM SILICATES
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CORROSIVE EFFECTS
DEVELOPING COUNTRIES
EUROPE
GEOTHERMAL FIELDS
GEOTHERMAL HEATING
GEOTHERMAL SPACE HEATING
GEOTHERMAL SYSTEMS
GEOTHERMAL WELLS
HEATING
HIGH TEMPERATURE
ICELAND
ISLANDS
LOW TEMPERATURE
MAGNESIUM COMPOUNDS
MAGNESIUM SILICATES
OXYGEN COMPOUNDS
SCALING
SILICATES
SILICON COMPOUNDS
SPACE HEATING
WELLS
WESTERN EUROPE