Study on calcium oxide pore size distribution changes during carbonation reaction for the greenhouse gas separation

In the present work, pore size distribution changes during lime carbonation reaction were modeled based on a population balance on the size of each pore in a random pore model of a non-catalytic gas-solid reaction with a solid product for the first time. Using this new approach, lime pore size distribution changes were predicted during the reaction with carbon dioxide within 500-700 degrees C for greenhouse gas removal from flue gases. Lime pore size distribution development predictions during carbonation reaction showed a close agreement with experimental data at various operating temperatures as well as solid conversions. Also, conversion-time profile for calcium oxide carbonation reaction was predicted by the above modeling framework with a good accuracy with respect to thermogravimeter results. Transition from rapid chemical control regime into slow diffusion control due to pore blockage was predicted by this conversion-time profile. Accordingly, this study can be used for better examining the calcium oxide behavior as an important engineering material for environmental pollution control systems.

Automated summary

In this study, the changes in pore size distribution during lime carbonation reaction were modeled using a random pore model based on a population balance for the first time. The predicted lime pore size distribution changes during carbonation reaction showed good agreement with experimental data, and the conversion-time profile for calcium oxide carbonation reaction was accurately predicted. This study is important for examining the behavior of calcium oxide as an important engineering material for environmental pollution control systems.