U-tube Sampling
The U-tube was developed to provide large volume samples of uncontaminated aliquots of subsurface fluid. U-tube samples are recovered to the surface at reservoir pressure isolated from contamination. The method is particularly suited for multi-phase fluid sampling in deep boreholes, as it is effective at recovering mixtures of gases and liquids. The following CO2 storage projects incorporated U-tube samplers:
2004-2006 Frio Brine Pilot
2007-2012 CO2CRC Otway Project
2009-2010 SECARB Cranfield DAS Test
2012- SECARB Citronelle Dome Anthropogenic Test
U-tube sampling is also a practical method for aqueous fluid sampling. U-tubes were installed in the following projects:
2006 NC-EWDP-24PB, Amargosa Valley, Nevada, Yucca Mountain Project S&T Study
2007 High Lake Project, Nunuvut Territory, Canada (NASA funded study on sub-permafrost microbes)
2009 Greenland Analogue Project, Kangerluusuaq, Greenland (SKB funded study on glacial margins)
The U-tube sampling system - CO2CRC Otway Project Residual Gas Saturation Test.
For a detailed description of the U-tube sampling method, see: