CO₂ Compression & Sequestration

Commercial Applications

A question that is often asked is 'What to do with the CO₂ after it has been captured?' Small quantities of essentially pure CO₂ can be used for industrial applications including carbonated beverages but, at the scale required for significantly reducing atmospheric CO₂ emissions, the two main options for CO₂ capture are (a) using CO₂ for Enhanced Oil Recovery (EOR) or (b) permanent sequestration. For these applications, it is necessary to compress CO₂ to about 150 bar. Multiple compressor stages with inter-stage cooling are necessary to reach this minimum miscible pressure for EOR.

Technology Information

CO₂ is first compressed through about three stages of compression, intercooling, and liquid knockout. It then goes through a dehydration step. The CO₂ dehydration step of the carbon sequestration process is critical because the moisture content will affect the material of the CO₂ pipeline as well as operational issues with hydrate formation.

The CO₂ then enters a fourth stage where it is compressed to supercritical conditions. It is then cooled in an aftercooler but no knockout is required since it is dry and in a dense phase.

The supercritical CO₂ then enters a multistage CO₂ pump/compressor and is discharged at the appropriate delivery pressure.

Project Information

KBR delivered the CO₂ Compression, CO₂ Dehydration, and the CO₂ Pipeline for the In Salah project in Algeria.