Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Water adsorption at high temperature on core samples from The Geysers geothermal field

Technical Report ·
DOI:https://doi.org/10.2172/661438· OSTI ID:661438

The quantity of water retained by rock samples taken from three wells located in The Geysers geothermal reservoir, California, was measured at 150, 200, and 250 C as a function of pressure in the range 0.00 {le} p/p{sub 0} {le} 0.98, where p{sub 0} is the saturated water vapor pressure. Both adsorption (increasing pressure) and desorption (decreasing pressure) runs were made in order to investigate the nature and the extent of the hysteresis. Additionally, low temperature gas adsorption analyses were performed on the same rock samples. Nitrogen or krypton adsorption and desorption isotherms at 77 K were used to obtain BET specific surface areas, pore volumes and their distributions with respect to pore sizes. Mercury intrusion porosimetry was also used to obtain similar information extending to very large pores (macropores). A qualitative correlation was found between the surface properties obtained from nitrogen adsorption and the mineralogical and petrological characteristics of the solids. However, there is in general no proportionality between BET specific surface areas and the capacity of the rocks for water adsorption at high temperatures. The results indicate that multilayer adsorption rather than capillary condensation is the dominant water storage mechanism at high temperatures.

Research Organization:
Oak Ridge National Lab., Chemical and Analytical Sciences Div., TN (United States)
Sponsoring Organization:
USDOE Office of Energy Research, Washington, DC (United States)
DOE Contract Number:
AC05-96OR22464
OSTI ID:
661438
Report Number(s):
ORNL/CP--97756; CONF-980111--; ON: DE98003559
Country of Publication:
United States
Language:
English