After the mixed air containing carbon dioxide (CO2) enters the pressure swing adsorption (PSA) device adsorption tower, the adsorption capacity of the adsorbent in the adsorption bed is different with the change of pressure. CO2 in the raw gas is absorbed under pressure, and the components that are not easy to be absorbed are removed from the outlet of the adsorption bed. When decompression occurs, the adsorbed CO2 and residual impurities are desorbed and desorbed. The concentrated CO2 is refined, and one part returns to the PSA system and the other part is canned in the form of liquid products。
The technology of Purification CO2 production plant by PSA
After the mixed air containing carbon dioxide (CO2) enters the pressure swing adsorption (PSA) device adsorption tower, the adsorption capacity of the adsorbent in the adsorption bed is different with the change of pressure. CO2 in the raw gas is absorbed under pressure, and the components that are not easy to be absorbed are removed from the outlet of the adsorption bed. When decompression occurs, the adsorbed CO2 and residual impurities are desorbed and desorbed. The concentrated CO2 is refined, and one part returns to the PSA system and the other part is canned in the form of liquid products
Feed gas：
Fermentation gas、Conversion gas、Decarburization and regeneration gas
Mine Gas
Other mixed gases containing CO2
Control mode and characteristics：
Control mode: The SPA device is controlled by the controller and meter. The controller can select DCS, FCS and PLC control system according to the scale and control requirements of the SPA device。
Characteristics: It not only realizes the conventional control of the system, but also realizes the expert control and adaptive optimization control of arbitrary combination and switching of multiple towers, which not only improves the operational flexibility of the device, but also ensures the long-term, stable and safe operation of the PSA device。
The methods of purifying carbon dioxide mainly include chemical absorption, low temperature separation and membrane separation.
1. Chemical absorption : This process uses an alkaline solution, such as sodium hydroxide, to absorb carbon dioxide, which is then acidified to release the highly purified carbon dioxide. The steps include: passing a gas containing carbon dioxide through a solution of sodium hydroxide, carbon dioxide reacts with sodium hydroxide to form sodium carbonate and water; The sodium carbonate solution is then treated with an acid, such as sulfuric acid, which releases carbon dioxide gas. This method is suitable for extracting carbon dioxide from the atmosphere, but requires the disposal of waste products from chemical reactions.
2. Cryogenic separation : By cooling a gas mixture to very low temperatures, the carbon dioxide condenses into a liquid while the other gases remain a gas and separate. This method is suitable for the extraction of high-purity carbon dioxide in large quantities, but requires complex equipment and energy.
3. membrane separation : a special membrane material is used to selectively let carbon dioxide through while other gases are blocked. This method is more efficient, but the membrane material selection and maintenance costs are higher.
Carbon dioxide recovery plant usually includes equipment such as scrubbers, compressors, coolers and dryers for purifying, compressing and storing carbon dioxide. These devices require regular maintenance and inspection to ensure efficient operation and safe operation.