A method of coupling direct air carbon dioxide capture technology with compressed air energy storage technology residual pressure and heat, characterized in matching a system of coupling direct air carbon dioxide capture technology with compressed air energy storage technology residual pressure and heat with renewable energy, wherein the system of coupling direct air carbon dioxide capture technology with compressed air energy storage technology residual pressure and heat with renewable energy comprises a compressed air energy storage system, a residual pressure control system (9), a residual heat centralized storage and control system (10), and a direct air carbon dioxide capture system, wherein
- the compressed air energy storage system comprises an air drying device (1), an air induction device (2), an air compression device (3), a first heat exchange system (4), a compressed air storage tank (5), a second heat exchange system (6), an expansion device (7), and a generator (8) connected in sequence;
- the direct air carbon dioxide capture system comprises an adsorption/desorption contactor (11), a CO2 compression device (12), a third heat exchange system (13), and a CO2 high-pressure liquefaction tank (14) connected in sequence;
- an air inlet end of the residual pressure control system (9) is connected to an air outlet end of the air induction device (2) through a first direct air capture (DAC) air passage (18) and to an air outlet end of the expansion device (7) through a second DAC air passage (19);
- an air outlet end of the residual pressure control system (9) is connected to the adsorption/desorption contactor (11);
- and a heat exchanger (16) is provided inside the residual pressure control system (9);
- and
- the residual heat centralized storage and control system (10) is connected to the first heat exchange system (4) through a first heat storage pipeline (20) to form an air compression heat recovery circulation pipeline, is connected to the second heat exchange system (6) through a first heat supply pipeline (21) to form a heated compressed air circulation pipeline, is connected to the adsorption/desorption contactor (11) through a second heat supply pipeline (22) to form a CO2 desorption circulation pipeline, and is connected to the third heat exchange system (13) through a second heat storage pipeline (23) to form a CO2 compression heat recovery circulation pipeline;
- and the residual heat centralized storage and control system (10) is connected to the heat exchanger (16) in the residual pressure control system (9) through a third heat supply pipeline to form a hot air circulation pipeline for regulating a temperature of air passing through the residual pressure control system (9);
- the method comprising the following two operation modes:
- operation mode 1:
- when the renewable energy is abundant, the compressed air energy storage system stores air;
- after the air enters the air drying device (1) and the air induction device (2), a part of air is compressed by the air compression device (3) and then stored in the compressed air storage tank (5), and the heat released in an air compression process is stored in the residual heat centralized storage and control system (10) through the air compression heat recovery circulation pipeline in the first heat exchange system (4);
- the other part of air enters the adsorption/desorption contactor (11) through the first DAC air passage (18) and the residual pressure control system (9), and is discharged after CO2 is adsorbed and removed by adsorbents in the adsorption/desorption contactor (11);
- the second heat supply pipeline (22) provides humidity and/or temperature conditions required for adsorbents to desorb CO2 in the adsorption/desorption contactor (11);
- the desorbed CO2 is compressed by the CO2 compression device (12) and then stored in the CO2 high-pressure liquefaction tank (14);
- and heat released in a CO2 compression process is stored in the residual heat centralized storage and control system (10) through the CO2 compression heat recovery circulation pipeline in the third heat exchange system (13);
- and
- operation mode 2:
- when the renewable energy is insufficient, compressed air stored in the compressed air storage tank (5) is heated by the second heat exchange system (6) and then enters the expansion device (7) to do work, which is used for the generator (8) to generate electricity;
- after doing work, air with a stable humidity, temperature and pressure enters the adsorption/desorption device (11) through the second DAC air passage (19) and the residual pressure control system (9), and is discharged after CO2 is adsorbed and removed by an adsorbents in the adsorption/desorption contactor (11);
- the second heat supply pipeline (22) provides humidity and/or temperature conditions required for adsorbents to desorb CO2 in the adsorption/desorption contactor (11);
- the desorbed CO2 is compressed by the CO2 compression device (12) and then stored in the CO2 high-pressure liquefaction tank (14);
- and the heat released in a CO2 compression process is stored in the residual heat centralized storage and control system (10) through the CO2 compression heat recovery circulation pipeline in the third heat exchange system (13).