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.