Design, process simulation and construction of an atmospheric dual fluidized bed combustion system for in situ CO2 capture using high-temperature sorbents

An atmospheric dual fluidized bed combustion system using high-temperature sorbents for in situ CO2 capture has been designed and simulated and is now under construction. The pilot plant is expected to burn petroleum coke and coal or biomass in a clean and efficient manner, generating a carbonator flue gas containing 2–5 mol% CO2, while producing a relatively pure carbon dioxide stream ready for compression. The concentration of sulphur dioxide in the resulting flue gas is expected to be on the order of a few parts per million by volume. Initial investigations are to be carried out using limestone-derived sorbents enhanced using a simple single step process for pore modification developed at CETC-Ottawa. Carbonation occurs in a two-stage fluidized bed carbonator–combustor allowing for optimal temperature control for both combustion (850–950 °C) and carbonation (650–750 °C). Calcination occurs in a single-stage fluidized bed combustor burning petroleum coke. Pilot plant operational data will be used for on-going scale-up activities using the ASPEN Plus process simulator.