CO₂ Capture in the Cement Industry

Publication Overview

The scope of the study was to:

• Provide descriptions of cement plants and the global cement industry;
• Review CO₂ capture processes that would be suitable for cement plants;
• Evaluate the performance and economics of cement plants with and without CO₂ capture;
• Discuss retrofitting CO₂ capture and CO₂ capture ready plants;
• Identify information gaps and R&D needs.

Publication Summary

The cement industry has made considerable strides in reducing CO₂ emissions but to make further major emission reductions CO₂ capture is required. The addition of CO₂ capture to new build cement plants to significantly reduce CO₂ emissions is technically feasible. Both post combustion and oxy-combustion options can be considered although the oxy-combustion option is not technically mature enough for deployment yet. Pre-combustion capture would be less suitable for cement plants because it would not capture the CO₂ from carbonate mineral decomposition, which account for about two thirds of the CO₂ from a modern cement plant.

The estimated costs of post combustion capture at new build cements plants are €107/tonne of CO₂ emissions avoided (US$161/t) for a 1 Mt/y European cement plant and €59/t (US$88/t) for a 3 Mt/y Asian plant. Use of alternative solvents and integration with an adjacent power plant could more than halve the costs. Oxy-combustion offers the lowest cost solution for CO₂ capture at new-build cement plants but further research and development is needed to address a number of technical issues to enable this technique to be deployed. Costs are estimated to be €40/tonne (US$60/t) of CO₂ avoided for a 1 Mt/y European cement plant and €23/t (US$34/t) for a 3 Mt/y plant in Asia.

The cost of CO₂ capture at a cement plant using oxy-combustion is expected to be similar to the cost of capture at a typical coal-fired power plant. The quantity of oxygen required per tonne of CO₂ captured is about three times lower at a cement plant but the economies of scale are less favourable. The cost of post combustion capture at a cement plant is expected to be substantially higher than at a power plant, mainly because of lower economies of scale and the need to install FGD, DeNOx and a boiler to provide steam for the regeneration of CO₂ capture solvent.

Post combustion capture could be readily retrofitted to existing cement plants provided sufficient space is available. Substantial rebuilding would be necessary to accommodate an oxy-combustion retrofit but this may nevertheless be the least cost option.