To solve such a problem that global warming intends to threaten human life and change even the environmental system, one of causes of the global warming is carbon dioxide and unnecessary carbon dioxide must be removed from the air first of all without controversy in order to stop the global warming right now, and the global warming must be stopped by our efforts for posterity or for nowadays as soon as possible before it is too late.

Carbon dioxide is captured from the air by utilizing the ash generated inevitably from an incinerator while making the energy consumption as low as possible. As one method, air or exhaust gas from the incinerator is made to pass through an ash-mixed liquid under pressure to capture carbon dioxide as carbonized, compounded, crystallized materials of carbon dioxide by ash.