Scaling– the Main Obstacle in Efficient Use of Geothermal Fluids

Abstract

When dissolved solids from the water precipitate and form solid deposits in geothermal plants and equipment, they affect the utilization of the geothermal resources. Solid deposition is a major problem in the harnessing of geothermal resources. To improve the efficiency of geothermal utilization, solid deposition must be prevented or controlled. This paper presents results from a research project aimed at the study of the composition and structure of depositions formed by direct heating utilization of geothermal waters. Firstly, the chemical composition of geothermal waters from three selected low-temperature geothermal wells was determined. The influence of the temperature on the composition of depositions was studied by using the speciation program, Watch. Then the deposits which appeared by geothermal water utilization were analysed, both chemically and structurally. There were made repeated tests with chemical inhibitors to attempt to control solid deposition. The results of the tests indicate that the inhibitors are efficient in controlling the scales even at low concentrations.