Application Carbon Storage

Potential storage sites for CO2 include non-producing oil and gas reservoirs, coal fields and deep saline aquifers. To reliably store CO2 in the subsurface, several factors must be considered, including the quality of the reservoir and the effectiveness of the seal in the cap rock. The quality of the reservoir is best characterized using porosity, permeability and pore size distribution data, and one of the key characteristics of a good seal cap rock is low permeability. NMR is well suited to investigate and understand all of these characteristics.

CCUS is a quickly expanding segment of research driven by mandates to reduce the amount of CO2 being emitted into the atmosphere. A lot needs to be understood about the reservoirs being considered for carbon storage and NMR/MRI can be a very useful tool in providing the reservoir understanding required. NMR/MRI technologies are uniquely positioned to provide data on pore networks, fluid flows, and gas-fluid-rock interactions directly related to the ability of reservoirs to store CO2.

Green Imaging can provide access to the following applications that can be of use for those looking at carbon storage.

Pore Network Characterization

NMR has always been seen as a very good measure of porosity, permeability and pore size distribution. In relation to CCUS applications, a detailed understanding of the pore network is essential to understanding how CO2 injected into the network will interact with the rock matrix, and with other fluids present in the network.

NMR measurements are a proven method of providing information on the pore size distribution, pore network connectivity, and wettability of the reservoir rocks.

Capillary Pressure

The behaviour of injected CO2 in a storage unit’s pore network is highly affected by capillary pressures within the network. Understanding the capillary pressure characteristics of the pore network is essential to understanding how CO2 will spread throughout the network. It is also key to ensuring a seal cap rock will remain intact once injection begins and then over the evolution of the carbon reservoir. Phenomena such as fingering and other multiphase fluid flow characteristics must be well understood in order to ensure the long term viability of a reservoir for CO2 storage.