School of Engineering



Materials for Next Generation CO2 Transport Systems (MATTRAN)

It is recognised that there is currently no standard definition for the composition of the CO2 stream expected from the different capture processes. Small levels of constituents can play a large role in the phase behaviour, thermodynamic properties and solubility of water in the supercritical CO2 stream.

The first tasks in the project are therefore to determine the expected ranges of compositional variation and conduct the necessary phase experiments in the supercritical range to characterise the behaviour of a selected subset of the CO2 streams judged to have the biggest impact. This experimental data will be used to address another gap in the existing knowledge on supercritical CO2 process streams, the prediction of the phase behaviour and thermodynamic properties using existing equations of state.

Currently there is no consensus in the literature regarding which equation of state provides the most accurate predictions in the supercritical range. This presents a problem for pipeline engineers in modelling the hydraulic behaviour of the CO2, both in the pipeline and in the event of an accidental or controlled release. In this project, the experimental data will be compared with existing equations of states and new models developed and provided to the hydraulic and fracture propagation models that will be used in the interconnected Work Packages.

The remaining Work Packages involve the specification of the pipeline and associated equipment materials to determine the conditions under which corrosion, stress corrosion cracking and fracture propagation will occur. Once the constituents in the CO2 stream have been selected, experiments investigating corrosion, stress cracking and fracture propagation will be conducted. This database of experimental data does not currently exist and without this data, the operating conditions of the pipeline and the property requirements of the materials cannot be safely defined.