Life cycle assessment of a CO2 mineralisation technology for carbon capture and utilisation in Singapore

Abstract Carbon capture and utilization (CCU) is one of the key pathways to abate carbon emissions. In this paper, the carbon abatement potential of a CO2 mineralization technology for CCU in Singapore is studied. Requiring mild reaction conditions, this technology uses 10 %–15 % (v/v) CO2 flue from a waste-to-energy plant and serpentine mineral (Mg3Si2O5(OH)4), to convert CO2 into solid carbonates or sand, which can then be used for purposes such as land reclamation. To study its carbon abatement potential more holistically, the life cycle or net carbon emissions were analysed by employing life cycle assessment (LCA) methodology. The results show that the CO2 mineralization technology abates 115.78 kg CO2-eq per tonne of CO2 input. The results also indicate that the major sources of emissions are from the land and sea transportation of serpentine mineral feedstock, the thermal activation of the feedstock, and carbon capture processes. Possible ways to increase the carbon abatement potential of this technology were explored, which included the sourcing of serpentine mineral from nearer regional locations, electrification of land transport for shipping serpentine, use of waste heat for thermal activation, and use of renewable energy to power the processes.