Management of Fluid Injection in Geothermal Wells to Avoid Silica Scaling at Low Levels of Silica Oversaturation

Basic Information
Author: Klein, C.W.
Description:In the design of geothermal installations, the possibility of scale precipitation caused by silica over saturation has often been taken as a design constraint upon steam separation pressure. At installations where over-saturation is allowed to develop, the resulting scale formation is a nuisance and in some cases affects the performance of injection wells. A review of the thermodynamics, reaction mechanisms, and kinetics of silica deposition, compared with actual experience at various locations, shows that it is possible to predict low-level scaling with sufficient confidence for production and injection system design. With foresight it thus becomes possible to suppress or manage the silica scale. A useful suppression technology is fluid pH reduction, achieved by mixing with non-condensible gases and or steam condensate. Results from several geothermal systems will be presented. Further improvements of predictive technique will benefit from more uniformity in data collection, designing experiments, reporting of results, and reporting measurements of scaling in actual production systems.
Publication Date:
Author Contact Information
Distributor Contact Information
Organization Name: Arizona Geological Survey
Street: 416 W. Congress St., Suite 100
City: Tucson
State: AZ
Zip: 85701
Phone: 520-770-3500
Geographic Extent
North Bounding Latitude: 38.3614
South Bounding Latitude: 35.1225
East Bounding Longitude: -117.949
West Bounding Longitude: -122.168