Realizing Complete Silica Removal -- Moving Technology from the Laboratory to Pilot Scale

Abstract

The condensation of silica to form hard scale is a major issue in the generation of energy from geothermal resources. In previous publications nano-structured calcium silicate (NCaSil) was presented as a solution to the formation of silica scale based on laboratory and field trials. The material is very promising, allowing complete removal of all silica from geothermal water which means geothermal energy can be extracted from brine down to ambient temperature. The next step in the development of the NCaSil technology was to translate the laboratory and field tests to pilot scale. For this purpose different scenarios had to be analysed and evaluated against each other. Models are presented that were used to select and compare three key scenarios and finally to decide on two of those to progress to pilot scale.