A middle-low temperature regenerated
carbon dioxide capturing absorbent is composed of the following components in percentage by weight: 10 to 80% of low temperature regenerated amine, 5 to 25% of pH adjuster, 0 to 10% of auxiliary agent, and the balance being water. When the absorbent is used, low temperature regenerated
carbon dioxide absorbent in an absorbing
tower reacts with gas containing
carbon dioxide to form a rich liquor, the absorbing temperature is 30 to 50 DEG C, and the absorbing
tower pressure is 0.05 to 6 MPa. The rich liquor is preheated in a barren liquor / rich liquor
heat exchanger to flash-evaporate part of carbon dioxide gas, after
flash evaporation the rich liquor is transferred to a regeneration
tower to carry out low temperature
pyrolysis, the rich liquor is converted into barren liquor, at the same time carbon dioxide is generated; the temperature of the bottom of the regeneration tower is 70 to 100 DEG C, the generated hot barren liquor in the regeneration tower is conveyed to the absorbing tower for capturing carbon dioxide after going through the
heat exchanger, and thus the whole absorption-regeneration-absorption circle is completed. The provided absorbent can be regenerated at a low temperature, and thus the capturing cost can be reduced in multiple aspects.