Working principles

The pressure adsorption oxygen generator is an automatic equipment that uses zeolite molecular sieve as an adsorbent to absorb and release oxygen from the air using the principle of pressurized adsorption and decompression desorption. Zeolite molecular sieve is a kind of spherical granular adsorbent with microporous surface and interior, which is white. Its pore type characteristics enable it to achieve the kinetic separation of oxygen and nitrogen. The separation of oxygen and nitrogen from zeolite molecular sieves is based on the slight difference in the kinetic diameter of these two gases. The nitrogen molecules have a faster diffusion rate in the micropores of zeolite molecular sieves and the oxygen molecular diffusion rate is slow. The diffusion of water and carbon dioxide in compressed air is not much different from nitrogen. It is the oxygen molecules that are eventually enriched from the adsorption tower. Subpressure adsorption oxygen production is the use of zeolite molecular sieve selection adsorption characteristics, pressure adsorption, decompression desorption cycle, so that the compressed air alternately into the adsorption tower to achieve air separation, thus continuously produce high-purity product oxygen.

The PSA oxygen generator uses a high-quality zeolite molecular sieve as an adsorbent based on the principle of pressure adsorption, and produces oxygen from the air under a certain pressure. After purification and drying of compressed air, pressure adsorption and decompression desorption were carried out in the adsorber. Due to the aerodynamics effect, the diffusion rate of nitrogen in zeolite molecular sieve Kongzhong is much greater than that of oxygen, nitrogen is preferentially adsorbed by zeolite molecular sieve, and oxygen is enriched in the gas phase to form finished oxygen. After decompression to normal pressure, the adsorbent is removed from the adsorbed nitrogen and other impurities to achieve regeneration. Generally, two adsorption towers are set up in the system, one tower is adsorbed to produce oxygen, and the other tower is deattached to regeneration. The opening and closing of the pneumatic valve is controlled by the PLC program controller, so that the two towers alternate to achieve continuous production of high-quality oxygen. purpose.

Systems processes

The whole system consists of the following components: compressed air purification components, air storage tanks, oxygen and nitrogen separation devices, oxygen buffer tanks.

1, compressed air purification components

The compressed air provided by the air compressor is first introduced into the compressed air purification assembly. The compressed air is first removed by the pipe filter to remove most of the oil, water, and dust, and then further removed by the frozen dryer to remove water, fine filter to remove oil, and dust. And the depth purification is carried out by the ultra-fine filter immediately following. According to the system working conditions, Chen Rui Company specially designed a set of compressed air remover to prevent the possible infiltration of trace oil, providing adequate protection for molecular sieves. A well-designed air purification component ensures the life of the molecular sieve. Clean air treated with this component can be used for instrument air.

2, air storage tanks

The role of air storage tanks is to reduce the pulse of the air flow and act as a buffer; The pressure fluctuation of the system is reduced, and the compressed air is smoothly purified through the compressed air assembly in order to fully remove oil and water impurities and reduce the load of the subsequent PSA oxygen and nitrogen separation device. At the same time, when the adsorption tower is switched, it also provides the PSA oxygen nitrogen separation device with a large amount of compressed air required for a short period of time to rapidly increase pressure, so that the pressure in the adsorption tower quickly rises to the working pressure, ensuring the reliable and stable operation of the equipment.

3, oxygen nitrogen separation device

There are two A and B adsorption towers equipped with dedicated molecular sieves. When the clean compressed air enters the inlet of Tower A and flows through the molecular sieve to the outlet, N2 is adsorbed by it, and the product oxygen flows out from the outlet of the adsorption tower. After a period of time, the molecular sieve in the A tower was saturated. At this time, Tower A automatically stops adsorption, compressed air flows into Tower B for nitrogen absorption to produce oxygen, and regeneration of Tower A molecular sieve. The regeneration of the molecular sieve is achieved by rapidly reducing the adsorption tower to atmospheric pressure to remove the adsorbed nitrogen. The two towers alternate for adsorption and regeneration, complete oxygen and nitrogen separation, and continuously output oxygen. The above processes are all controlled by programmable program controllers(PLCs). When the oxygen purity of the exhaust end is set, the PLC program functions to automatically empty the valve and automatically empty the unqualified oxygen to ensure that the unqualified oxygen does not flow to the gas point. When the gas is released, the noise is less than 75 dBA by silencer.

4, oxygen buffer tank

Oxygen buffer tanks are used to balance the pressure and purity of oxygen separated from the nitrogen oxygen separation system to ensure continuous supply of oxygen stability. At the same time, after the adsorption tower is switched, it will recharge some of its own gas into the adsorption tower. On the one hand, it will help the adsorption tower to increase pressure, and it will also play a role in protecting the bed layer. It will play a very important role in the process of equipment operation.

 Technical indicators

Oxygen production: 5-200N m3/h

Oxygen purity: 90 % -93 %

Oxygen pressure: 0.3 Mpa

Dew point: -40 °C(under normal pressure)

Technical characteristics

1. Compressed air is equipped with air purification and drying treatment device, clean and dry air, which is conducive to the long-term service life of molecular sieves.

2. The new pneumatic cut-off valve adopted has a fast opening and closing speed, no leakage, long switching life, and can satisfy the variable pressure adsorption process frequently and has high reliability.

3. Perfect process design, selection of new molecular sieves

4. Adopt new oxygen production festival, continuously optimize the device design, reduce energy consumption and capital investment

5. Compact equipment structure design, reduce land area

6. The equipment performance is stable, using PLC control, can achieve full automatic operation, the annual operation failure rate is low

Field of application

1. Electric furnace steelmaking: decarbonization, oxygen combustion heating, foam slag, metallurgical control and post-order heating.

2. Wastewater treatment: aerobic aeration of activated sludge, oxygenation of pools and ozone sterilization.

3. Glass melting: Oxygen to help dissolve, cut, increase glass production, and extend the life of the furnace.

4. Pulp bleaching and papermaking: Chlorinated bleaching into oxygen-rich bleaching, providing cheap oxygen, sewage treatment.

5. Non-ferrous metal smelting: Metallurgical steel, zinc, nickel, lead, etc. need to be oxygen-rich, and the PSA method is gradually replacing the deep cold method.

6. Oxygen for petrochemicals and chemicals: Oxygen reactions in petroleum and chemical processes use oxygen rich instead of air for oxidation reactions, which can increase reaction speed and chemical product production.

7. Ore treatment: Used in gold and other production processes to increase the extraction rate of precious metals.

8. Aquaculture: Oxygen-rich aeration can increase the dissolved oxygen in the water, greatly increase the yield of fish, and can deliver oxygen for live fish and intensively raise fish.

9. Fermentation: Oxygen rich instead of air is an aerobic fermentation to provide oxygen, which can greatly improve the efficiency of drinking water.

10. Ozone: Provides oxygen to ozone generators and self-oxygenation sterilization.

Purity, flow, pressure stability can be adjusted to meet the needs of different customers.