CO2 separation and storage (CCS)

       

Further reading

• The University of Stanford (156)
• CO2 separation project (126)

New techniques

Storing CO₂ in geologic structures is an interesting proposal for mitigating the contribution of fossil fuels to global warming. But to become a viable large-scale option, two technical barriers need to be overcome. The CO₂ must first be economically separated from other atmospheric gasses. And once it is successfully sequestered underground, the CO₂ must be permanently and accurately monitored at a reasonable cost to determine if there is any movement of the injected CO₂ and the degree of risk of its subsequent escape back into the atmosphere. Academic R&D projects are currently investigating both of these problems.

Inorganic membranes

In a collaborative effort, the Energy Research Centre of the Netherlands (ECN), the Delft University of Technology (TU Delft), and the University of Stanford are investigating the use of inorganic membrane materials for H₂ and CO₂ separation. Until now, CO₂ separation has relied on organic membranes, which have a low melting point. They are therefore not suitable for use during combustion activities. It is hoped that new membranes currently under development will be able to operate at temperatures over 400°C. The ability to function at the source of combustion would make them a much more attractive and efficient option.

High speed, low cost monitoring system

The University of Stanford has proposed the Stanford Cross Linear Array, a high speed and low cost solution to monitor underground CO₂ reservoirs. In this technique, the sources and detectors are distributed along three linear arrays, two along the surface and one along the injection borehole. The three-axis array provides a degree of three-dimensional resolution but at greatly reduced acquisition, resulting in a processing cost at the order of magnitude of a two-dimensional surface array.