The chemistry of geothermal waters: its effects on exploitation

The aim of this paper is to demonstrate all aspects of the way in which chemistry affects exploitation of geothermal fluids: through scaling and corrosion and their treatment, through its influence on production characteristics, environmental considerations and also in the possible recovery of valuable by-products. It is therefore essential that the chemical characteristics and behaviour of fluids are evaluated fully in order to optimize the design, operating conditions and management of a commercial geothermal system. Careful sampling and accurate measurements are thus indispensable. Chemical computer models are shown to be valuable tools for studying the chemical behaviour of a fluid in various situations; a brief illustration using the TPDEGAZ code is given.