CO₂ capture by calcium aluminate pellets in a small fluidized bed

Synthetic pellets made using calcium aluminate cement and quicklime have been examined in a small fluidized bed reactor to determine their performance in cyclic CO₂ capture for up to 20 calcination/capture cycles. Two batches were examined one a "fresh" batch, and the second an "aged" batch of pellets and their performance was compared with the original parent limestone. Carbonation was carried out at 650°C and calcination at 900°C, both with 15% CO₂, balance N₂, as a synthetic flue gas. Experiments were also performed with and without steam in the flue gas and showed that steam always improved capture performance. In addition, there was no major attrition associated with the pellets, and pellets tended to perform better in terms of carbon capture than the parent limestone.