Understanding particle adhesion in CaCO3-CaO powder at high temperatures

Handling of particulate looping materials at high temperatures (500-800 degrees C) is important for the effective operation of chemical looping. Particles can exhibit high adhesion at high temperatures, which can lead to operational problems in chemical looping. Herein, particle adhesion in CaCO3-CaO, a looping material, was carefully investigated at 500-800 degrees C. Particle adhesion in CaCO3 increased with increasing temperature and retention time under most of the investigated conditions. The increase in tensile strength was attributed to weak sintering of CaCO3. However, the tensile strength decreased with increasing retention time at 800 degrees C. This phenomenon was specific to 800 degrees C, where decarboxylation progressed rapidly. The CO2 gas generated by decarboxylation formed voids in the powder bed, which increased the porosity of the powder bed, resulting in a decrease in the tensile strength. In addition, gas release via decarboxylation broke the weak sintered structure, resulting in a brittle powder bed. (c) 2025 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan. All rights are reserved, including those for text and data mining, AI training, and similar technologies.