NGL's core-flooding and imagining capability is highly-specialised and can be used for carbon storage research as well as applications in the oil and gas industry.
Core-flooding is a technique used for conducting experiments on core samples in conditions simulated to be as close to the natural environment as possible.
In this case, it often means mimicking burial of the core to several kilometres depth and at elevated temperatures. Core-flood experiments are used to measure the permeability and porosity of samples as well as determining how they are affected when the sample is flooded with fluids, chemicals or gas. Using the results of core-flood experiments researchers can predict how different fluids or gases would move through the sampled area. This information can be used to improve our numerical models to determine changes over wider areas.
A Medical X-ray CT scanner is used to image the interior of rock samples and visualise how the whole system behaves when other fluids or gases are flooded through the core.
The core is placed in a core holder before it is run through the X-ray CT scanner. For standard core flooding, typically the core holders are made of steel which are incompatible with the scanner. However the holders used during X-ray imaging are made of aluminium and carbon fibre which are X-ray transparent.
Core of 1.5” (3.8 cm) and 4” (10.2 cm) diameters can be taken from a well and confining pressure is applied to the samples to simulate reservoir conditions. Fluids are then flowed through the core to see how the rock behaves, both during flow to test relative flow rates for relative permeability and relative saturation, homogeneity and gravity segregation; and at the end of the flow to test….. The core can be angled to ensure that there is a good visualisation of the water and gas in the sample.
The X-ray CT scanner provides valuable information in site characterisation to develop a geological model of the area.
Coupled with NGL’s tracers facilities, a slim tube can also employed in the same way as the core holders to look at fluid and gases in rock particles or sediment. This is a faster way of obtaining measurements.
Australian Resource Research Centre, Kensington, Perth
Linda Stalker
Linda.Stalker@csiro.au
Integrity of the rock, relative permeability, rock reactivity and injectivity can all be investigated to provide valuable information on site characterisation to develop a geological model of the area.
The equipment can also be used in Enhanced Oil Recovery, and has applications in the oil and gas industry.