The system provides critical reservoir description data at reservoir temperature,
pore pressure and confining stress. The system is configured to provide steady state
porous plate capillary pressure data and simultaneous electrical properties ("F",
"RI", "Sw", "m", "n", "Ro", "Rt") data with reservoir fluids. The capability to
determine Rw at test conditions is also included in the system, which also incorporates
the latest benefits of Core Labs client focussed R&D program. The system is rated
to 10,000 psig confining pressure, 9,500 psig pore pressure at a temperature of
150 °C and features automated data acquisition and semi-automated operation.
Data calculation and report software are included.
Summary of Operation: (Restored State). Plug samples of known porosity
and permeability are saturated with simulated formation brine, the Rw of the brine
determined at reservoir temperature and pressure in the Reservoir Conditions Brine
Resistivity Cell. The core plugs and downstream water wet (hydrophilic) ceramic
plates are saturated with the brine, wetting phase, and placed in the core holder.
Unconsolidated samples are mounted, frozen, in Teflon sleeves incorporating two
electrical terminals. The sample and plates are then subjected to brine flow through
at confining pressure and test backpressure to ensure 100 percent brine saturation.
Saturation is confirmed by measuring a reproducible Ro on the sample at test conditions.
The upstream pump cylinder injects the displacing phase (oil) at constant pressure
whilst the down stream pump cylinder maintains the differential pressure across
the porous plate and collects the effluent wetting phase (brine) from the core holder
providing accurate fluid measurement that is logged by the host computer along with
all experimental parameters. Electrical measurements can be made in both four and
two electrode modes and at either fixed frequency or a frequency scanned to produce
a minimum phase angle. The experimental data for each sample are logged to hard
in the host computer and used in the report generation software for final report
generation. Newly developed proprietary PcMax plates allow pore entry pressures
of up to 1,500 psig to be obtained allowing, for the first time, analysis of very
low permeability samples by this method.