Cut-away diagram of constant volume and radial flow (CVRF) gas migration apparatus.
Apparatus and experimental methodologies are custom designed to meet the precise requirements of the client and work programme.
Experiments can be performed on intact or fractured rock as well as interfaces between neighbouring materials.
Experiments are performed under simulated down-hole stress, pore pressure and chemical conditions using triaxial, isotropic (hydrostatic) or constant volume cells.
High accuracy heavy duty shear box systems have been developed to examine fracture, fault and interfacial flow.
Apparatus is assembled in a constant temperature test chamber which is regulated to better than ±0.3°C or within oven or high precision incubators.
Pressure and flow-rates are precisely set or monitored using microprocessor-controlled syringe pumps.
Experiments are remotely controlled and test parameters recorded using customised code developed using the National Instruments LabVIEW™ software package.
With careful attention to experimental design, choice of instrumentation, calibration and regulation of testing conditions, the laboratory is able to quantify key properties for intact, fractured and flow along interfaces for low permeability materials.
capillary entry breakthrough and threshold pressures
gas permeability function
drained and undrained compressibilties
rheological (creep) properties
Concepts developed in the laboratory have also been applied to field investigations. The TPRL has also been commissioned to design, monitor and interpret a large scale gas injection test (Lasgit) examining the movement of repository gases through compact buffer bentonite. Lasgit is a full-scale demonstration project conducted at the Äspö Hard Rock Laboratory in Sweden at a depth of 420m. State-of-the-art experimental monitoring and control systems are housed in a ‘gas laboratory' which is a self-contained unit designed and assembled by BGS within a modified shipping container. A customised graphical interface enables remote control and monitoring to be undertaken by staff at BGS headquarters in Keyworth.
laboratory studies examining gas, water and solute movement