The component selection of the CO2 extraction machine should first analyze the process requirements and select the components of the CO2 extraction machine with good operation reliability, simple structure, convenient maintenance, and low price among the members of the CO2 extraction machine that can basically meet the requirements of the CO2 extraction process.
6 process requirements for supercritical CO2 extraction machine
The most basic task of a CO2 extraction machine is to realize the predetermined CO2 extraction process. Therefore, it is imperative to carefully study and analyze the requirements of the CO2 extraction process for the CO2 extraction machine.
Medium Characteristics of CO2 Fluid Extraction
The physical and chemical properties of raw materials, intermediate products, final products, and by-products involved in the supercritical CO2 extraction process
Extraction capacity of a CO2 extraction vessel
The production scale of CO2 extraction has a great relationship with the selection of CO2 extraction machine specification and CO2 extraction type. For example, piston compressors are suitable for small and medium gas volumes and various pressures (small CO2 extraction machines), and centrifugal compressors are suitable for large volumes and low pressures.
Changes in process CO2 extraction parameters during operation
Changes in operating conditions are inevitable during operation, and possible extreme temperature, pressure, flow, liquid level, etc. must be taken into account. Components of the selected O2 extraction machine (such as CO2 extraction pumps) should have the capability of appropriate process parameter changes. Centrifugal compressors have limited adjustment ability to reduce displacement, and adjustment of gas volume may easily cause a unit surge. Special attention should be paid to the suction characteristics of the CO2 extraction pump to transport high-temperature liquids to avoid cavitation.
Target material selection for CO2 extraction
Production CO2 extraction process parameters such as temperature, pressure, whether the material is corrosive, whether the product has special requirements for impurity pollution
Operation control method
The operation control mode of the CO2 extraction machine is determined by the influence of changes in flow, temperature, pressure, liquid level, and other parameters on the production operation control mode. Generally speaking, both automatic and manual are acceptable, but in some occasions, manual adjustment accuracy cannot be achieved, and automatic control must be used.
Leak-proof, moisture-proof, explosion-proof, and other special structural requirements
Five key points in the selection of supercritical CO2 extraction machine components
After careful process analysis, the requirements for the CO2 extraction machine are very clear, and there is a basis for choosing the components of the CO2 extraction machine. Generally speaking, in order to meet the requirements of a special CO2 extraction process, there are often multiple models.
- Reliability: In modern supercritical CO2 extraction equipment, a stand-alone system is often used, and a failure of one CO2 extraction machine means a production stop. Investigate with a CO2 extraction machine.
- Performance: good adaptability to parameter changes in CO2 extraction production, high efficiency, and low energy consumption
- Operation and maintenance: easy assembly and disassembly, stable operation and operation, once a fault occurs, it must be displayed in time so that it can be eliminated as soon as possible to avoid major losses
- Structure: Give priority to models with few friction parts, no power imbalance or better power balance performance, and no periodic performance changes. Minimize the service life of the CO2 extraction machine due to friction and power imbalance
- Price: low price, high quality
Selection of Supercritical CO2 Extraction Pump
The process flow of supercritical CO2 fluid extraction is generally divided into two types: a compressor and a high-pressure pump according to the type of delivery equipment. Read More: Supercritical carbon dioxide Wikipedia
- Compressor: The use of a compressor is because the extraction solvent after separation and recovery does not need to be condensed into a liquid, and can be directly pressurized, but the volume of the compressor required to deliver the same flow rate of the extraction agent is relatively large, and due to the isenthalpic compression process will generate a lot of pressure. For large temperature rise, an intermediate cooling system must be configured, the compressor is noisy and the working environment is harsh;
- High-pressure pump: The process using a high-pressure pump has the advantages of large delivery volume, low noise, small thermal effect, low total energy consumption, and stable and reliable delivery process. The disadvantage is that the supercritical CO2 fluid must be liquefied into a liquid by condensation before it enters the pump. , so a condensing system is required.
Through the comprehensive analysis of factors such as process economy, equipment reliability, and energy consumption, and considering the characteristics of the supercritical CO2 fluid used, compressors and high-pressure pumps can be selected for supercritical CO2 extraction pumps.