TECHNICAL AND ECONOMIC RISK OF POST-COMBUSTION CARBON CAPTURE AND STORAGE SYSTEMS INTEGRATED INTO CEMENT PLANTS

Investing in Carbon and Capture Storage (CCS) is critical in meeting the cement industry’s net-zero decarbonisation target by 2050. Two post-combustion CCS processes were discussed: the conventional monoethanolamine (MEA) based CCS process and the novel silica-alkoxylated polyethyleneimine (SPEI) based CCS process able to remove 90% of CO2 from the flue gas. A preliminary hazard analysis was used to assess the technical risks, and a Monte Carlo analysis was applied to quantify the economic risks of investing in the processes, considering the uncertainties derived from the supply cost for feedstock, cement selling price, sorbent purchasing cost, energy cost and the emission allowance price. The work demonstrates that investing in new cement plants with 70% free allowances, without a CCS system, and using the current fuel sources (RDF, coal and waste tyres) is challenging, with a probability of having a negative Net Present Value and an Internal Rate of Return below 6%, of 55% and 46%, respectively. CCS can reduce such risk below 6%. The lower technical and economic risk of the novel SPEI based CCS system compared to MEA is mainly derived from the lower operation temperature (120oC versus 150oC) and lower regeneration energy requirement (2.85GJ/tonne CO2 versus 4.25 GJ/tonne CO2).