An air separation machine is a device used to separate a mixture of gases into different components. Its role is to separate oxygen, nitrogen, argon and other components in air or other gases in order to facilitate the needs of various industrial production. The basic principle of the air separation device is to use the boiling point difference of different gases to separate the mixed gas into a single gas component through compression and cooling technology.
coalification ceramics air separation production plant manufacturer
Air is a uniform multi-component gas mixture. Within 10km of the ground, its main components, such as nitrogen, oxygen and argon, are almost constant. In addition, there are small amounts of impurities, such as dust, CO2, water vapor, hydrocarbons such as SO2, CH4, C2H6, C3H8, etc. These components change with the environment. In addition, there are trace amounts of H2, ozone, N2O and so on. As the altitude increases, the amount of oxygen in the air decreases. Impurity content and altitude are the main factors to consider in the design.
The air separation device is a device based on the principle of gas condensation and evaporation, which is mainly used to separate various components in gaseous mixtures. The basic principle is to use the difference of boiling points of different components at low temperatures to separate the gas mixture into different components through continuous cooling, compression, expansion and heating processes. The core of the air separation device is the adsorbent, which generally uses molecular sieve and activated carbon and other substances.
Application field of air separation device
- Chemical industry: Air separation device is widely used in alumina, chlor-alkali industry and other fields, for producing nitrogen, oxygen, hydrogen and other gases. At the same time, the air separation device can also be used for gas separation in various chemical reactions.
- Energy industry: Air separation devices are also widely used in coal chemical industry, natural gas hydrogen production and other fields. It can separate hydrogen, methane and other gases in natural gas through high pressure compression and low temperature cooling technology for hydrogen production or other energy production.
- Pharmaceutical industry: In pharmaceutical production, many drugs need to use pure nitrogen or pure oxygen as a carrier to ensure the quality and effect of drugs. At this time, the air separation device can be used to separate the nitrogen and oxygen in the mixed gas for the production of drugs.
- Other industries: In addition to the above fields, air separation devices can also be used in food processing, metallurgy, electronics and other fields. In food processing, nitrogen and oxygen can be used as preservation and oxidation control agents, while in the electronics industry, air separation devices can be used to manufacture pure gases for the production of electronic components.
The above is the role of the air separation device and application field introduction. With the continuous development of technology, the application scenarios of air separation equipment are more and more extensive, and its role is becoming more and more important.
Common device types in air separation technology include membrane separation, adsorption separation and steam liquefaction separation
1.Membrane separation device
Membrane separation is a technique for separating a mixture into two distinct components by means of a semi-permeable membrane. Common membrane separation devices include reverse osmosis membrane, ultrafiltration membrane and gas separation membrane. Reverse osmosis membranes are mainly used in the field of seawater desalination and wastewater treatment, ultrafiltration membranes are mainly used for separation and concentration in biochemical engineering, and gas separation membranes are mainly used for air separation and natural gas processing.
2. adsorption separation device
Adsorption separation is a technique that uses a solid adsorbent to physically or chemically interact with certain components in the mixture to separate them from the mixture. Common adsorption separation devices include activated carbon adsorbers, molecular sieve adsorbers and membrane adsorbers. Activated carbon adsorbers are mainly used for water treatment and air purification, molecular sieve adsorbers are mainly used for gas processing and air separation, and membrane adsorbers are mainly used in the petrochemical field.
3. steam liquefaction separation device
Steam liquefaction separation is a technique that takes advantage of the differences in the boiling points of the different components in a mixture by heating and evaporating the mixture into a gaseous state, and then liquefying it into the different components by condensation. Common steam liquefaction separation devices include distillation column, extraction column and absorption column. The distillation tower is mainly used in the fields of oil refining, chemical industry and food processing, the extraction tower is mainly used for organic synthesis and drug production, and the absorption tower is mainly used for gas purification and environmental protection.
In summary, common device types in air separation technology include membrane separation, adsorption separation and steam liquefaction separation, and the specific number varies according to the application scenario. Different device types have different application scenarios and working principles, which need to be selected and designed according to specific conditions in practical applications.
Air separation equipment product series
Large and medium-sized air separation equipment product series
- Oxygen purity :≥99.6%O2, nitrogen purity :≤10ppmO2, argon purity :≤ 2ppmO2+≤3ppmN2.
- Oxygen and nitrogen output is 0℃, 0.101325MPaA gas quantity.
- The unit energy consumption of oxygen production is based on the design value of the amount of air entering the tower.
- Liquid products are the reference for selection, and the amount of liquid products can be adjusted between liquid oxygen and liquid nitrogen. When the liquid product is different from the above value, the unit power consumption index shall be in accordance with the contract.
- When nitrogen purity and oxygen-nitrogen ratio do not conform to the provisions in the table, the contract shall be followed.
- Air separation equipment is recommended to use product series, can also be customized according to customer needs.
- The process form adopts molecular sieve purification, supercharged turbine expansion and external compression process. Internal compression processes can also be used according to customer requirements.
Complete small air separation product series
- Oxygen and nitrogen output is 0℃, 0.101325MPaA gas quantity.
- The unit oxygen power consumption does not include the oxygen compressor consumption value.
- Oxygen and nitrogen concentrations are percentage by volume.
- Nitrogen output: Oxygen output ≥ 2:1
- The power consumption index of some liquid products produced at the same time shall be in accordance with the contract.
Complete sets of high purity nitrogen equipment product series
- Nitrogen output is the amount of gas at 0℃ and 0.101325MPaA.
- Unit nitrogen energy consumption is based on the design value of air intake into the tower.
- Liquid products for selection reference, when the liquid products and the above values are different, the unit power consumption index in accordance with the contract.
Full liquid air separation equipment products
- Oxygen purity :≥99.6%O2, nitrogen purity :≤10ppmO2, argon purity :≤ 2ppmO2+≤3ppmN2.
- The output of liquid oxygen, liquid nitrogen and liquid argon is the amount of gas at 0℃ and 0.101325MPaA, and Y in the model indicates the liquid volume “liter”.
- The liquid product quantity is the reference for selection, the liquid product quantity can be adjusted between liquid nitrogen and liquid oxygen, and the unit energy consumption index is stipulated in the contract.
- When nitrogen purity and oxygen-nitrogen ratio do not conform to the provisions in the table, the contract shall be followed.
- The process form adopts molecular sieve purification, the device below 50T/D adopts expansion machine and low temperature refrigerator liquefaction process, and the device above 50T/D adopts high and low temperature double expansion machine liquefaction process.
- Due to the high energy consumption of all-liquid products, it is recommended to choose imported raw gas compressors and circulating gas compressors and imported booster expansion machines.
Optimization method of air separation equipment
The optimization methods of air separation equipment mainly include improving the efficiency of cold box, reducing energy consumption and extending the life of equipment. Among them, improving the efficiency of the cold box is the most critical point, which can be achieved by adjusting the circulation mode of the refrigerant and increasing the heat exchange area. In addition, reducing energy consumption is also an important optimization goal, which can be achieved by optimizing the design of the compressor and increasing the efficiency of the cooler. Extending the life of the equipment requires regular maintenance and maintenance to ensure the stability and reliability of the equipment.
Internal structure of air separation equipment
The internal structure of the air separation equipment includes key components such as cold box, evaporator, compressor and separation tower. Among them, the cold box is the core of the air separation equipment, and it is also one of the most critical components of performance. The cold box contains a cooler, heat exchanger, evaporator, liquid gas storage tank and other components, which work through the refrigerant circulation to remove impurities such as water vapor in the air, so as to achieve the purpose of improving the separation efficiency. The evaporator and the compressor are two important parts of the cold box, the evaporator converts the liquid air into gaseous air, and the compressor compresses the gaseous air, increasing its temperature and pressure, so that it is easier to further separate.
Working process of air separation equipment
The working process of air separation equipment mainly includes several steps such as compression, cooling, film separation and recompression. First, the air is compressed by a compressor to increase its temperature and pressure, and then cooled by a heat exchanger to remove impurities such as water vapor. The air then enters the evaporator and is divided into liquid and gaseous parts, the liquid air is stored in the liquid gas tank, and the gaseous air enters the separation tower for further separation. Finally, oxygen, nitrogen and other components are separated and recompressed to obtain the required pure oxygen or nitrogen.