Indirectly heated carbonate looping cycles in cement plants for CO2 capture and storage

• The decarbonisation of the cement industry using carbonate looping cycles. • Technical modelling of indirectly heated carbonate looping concepts. • The use of heat pipes to transfer thermal energy to the calcination process. • Economic assessment of tail-end and fully integrated CO 2 capture cycles. • The fully integrated option shows superior technical and economic performance. The concept of Carbonate Looping Cycle (CaL) offers many advantages compared to other CO 2 capture technologies within cement plants. The configurations currently discussed in the literature employ oxy-fuel combustion to supply the necessary heat for the calcination process in a single reactor. As a result, the process requires an air separation unit. The indirectly heated calcium looping (IHCaL) offers solutions to overcome the present limitations. Numerous heat pipes connecting a separate combustion unit to a calciner supply thermal energy for the calcination process. This study, based on the best available technology, recommends both full and tail-end IHCaL integrations within a commercial cement plant. Both systems provide over 1.3 million tonnes of cement per annum. The fully integrated option produces 309 GWh of electricity, compared to 875 GWh for the tail-end option. The CO 2 avoidance rates for fully integrated and tail-end options are 0.83 and 0.88 t CO 2 /t Clinker, respectively. The tail-end version has a notably high capital cost, resulting in a high CO 2 avoidance cost of €37.6/t CO 2 . On the other hand, the fully integrated version lowers the CO 2 avoidance cost to €29.8/t CO 2 because of a lower capital requirement and a smaller gap between the amount of CO 2 captured and avoided.