Typical analytical measurement of geothermal well fluid chemistry requires sampling at the surface due to the extreme temperature and pressure found in downhole environments. However, data collected at the surface does not provide depth information and makes determining which rock layers are producing a particular ionic species difficult. We are developing a series of rugged high temperature and pressure stable ion selective electrodes that are integrated with a pH electrode, temperature, and pressure sensors. The goal of this effort is to collect real-time pH and ionic species concentration data at depth with temperature up to 225 �C and pressure up to 5000 psi. We will present data showing the measurement of Li+, Cs+, F-, and I- concentration at high temperature and pressure in a laboratory scale autoclave. These ions were chosen because they have been used as tracers in geothermal reservoir characterization experiments in the past. However, this technology is applicable to the measurement of other ionic species depending on the reservoir temperature.

Development of a downhole instrument for measuring real-time concentration of ionic species in geothermal wells

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.