Dac apparatus

A DAC apparatus configured to recover CO2 in the atmosphere, comprising:

• an adsorption chamber provided with an adsorbent for adsorbing or absorbing CO2;
• an atmospheric control valve configured to open the adsorption chamber to the atmosphere or seal the adsorption chamber from the atmosphere;
• a vacuum pump connected with the adsorption chamber through vacuum piping;
• a vacuum control valve provided on the vacuum piping;
• a heating device configured to heat the adsorbent;
• a pressure sensor configured to detect a pressure of the adsorption chamber;
• and
• a controller configured to control the atmospheric control valve, the vacuum control valve, and the heating device to sequentially perform an adsorption step, a deaeration step, and a desorption step, the adsorption step circulating the atmosphere into the adsorption chamber and adsorbing CO2 in the atmosphere to the adsorbent, the deaeration step deaerating and depressurizing the atmosphere in the adsorption chamber, the desorption step heating the adsorbent in a state in which the adsorption chamber is depressurized and desorbing CO2 from the adsorbent, wherein
• the controller ends the deaeration step when a state in which a change amount per unit time of the pressure detected by the pressure sensor is equal to or smaller than a predetermined amount continues for a predetermined time after starting the deaeration step.