The CO2 recovery system is a critical component of a supercritical CO2 extraction machine. In this process, the CO2 that is used as a solvent is recovered and recycled, reducing both costs and environmental impact. However, it is important to understand that it is not possible to recover 100% of the CO2 used in the extraction process. The percentage of CO2 that can be recovered will depend on various factors, such as the efficiency of the system, the cost of CO2 in the local market, and the objectives of the extraction project.
Pressure balance method
The easiest method of recovering CO2 is by using the pressure balance method. In this method, the high-pressure CO2 used in the extraction process is sent to a CO2 storage tank at a lower pressure. This method is simple and effective, but it does not recover all of the CO2. If a higher percentage of CO2 recovery is desired, a compressor can be installed in the system. The compressor will compress the CO2, increasing its pressure and allowing for greater recovery. In this case, a purifier is also installed in front of the CO2 storage tank to ensure that the CO2 is free of impurities.
Level of CO2 recovery required
It is important to note that the level of CO2 recovery required will depend on the specific circumstances of the extraction project. If the cost of CO2 is high in the local market, it may be more economical to recover a higher percentage of CO2. On the other hand, if the cost of CO2 is low, it may be more cost-effective to recover a lower percentage of CO2. Generally, recovering about 80% of the CO2 used in the extraction process is suitable for most projects. Constantly replenishing some fresh CO2 can also help to ensure complete extraction and optimize the extraction process.
Safety of the CO2 recovery system
In addition to the method of CO2 recovery, it is also important to consider the safety of the CO2 recovery system. CO2 is a high-pressure gas, and it can be dangerous if not handled properly. The CO2 storage tank and compressor should be designed and installed with safety in mind. Pressure relief valves, pressure gauges, and other safety devices should be installed to prevent over-pressurization and ensure safe operation of the system.
Final words
The CO2 recovery system is an essential component of a supercritical CO2 extraction machine. Choosing the right method of CO2 recovery will depend on the specific circumstances of the extraction project, such as the cost of CO2 in the local market and the objectives of the project. The safety of the CO2 recovery system should also be considered to ensure safe operation of the equipment.