Abstract The integration of an aluminium plant and post-combustion CO 2 capture has been investigated and the different integration possibilities have been evaluated technically and economically. The technology used for aluminium production is the Hall-Heroult and the current cell design necessitates that large amounts of false air is supplied to the cells. This results in a CO 2 concentration in the process gas at around 1 vol%, which is considered uneconomical for CO 2 capture. By increasing the CO 2 concentration to 4 vol% implementation of CO 2 capture becomes more likely and this is therefore the basis of the current investigation. Two integration tasks have been undertaken, one is placement and configuration of the post-combustion CO 2 capture plant relative to the aluminium plant (160 kt CO 2 /yr), and the second is energy integration options for CO 2 capture. The results showed that there is flexibility in placement and configuration of the capture plant as aluminium plants are likely to be stretched over large distances. The investigation of the energy integration options was based on the assumption that 85% of the CO 2 produced in the aluminium production was to be captured. The benefit of utilizing waste heat from the aluminium production for use in CO 2 capture was confirmed and it was found that approximately 65% of CO 2 could be captured using waste heat. The additional energy needed for capturing the remaining 15% of the CO 2 could then either be generated in an external energy plant, fired with coal, natural gas or biomass, or with electricity taken from the grid. The burning of fossil fuels in the energy plant results in increased CO 2 generation which is also included for CO 2 capture so that the assumption that 85% of the CO 2 from the aluminium production was maintained. The results of the cost estimation showed there is some advantage to using