1、 Principle of Carbon Molecular Sieve Air Separation for Nitrogen Production

The carbon molecular sieve produced by our company is an adsorbent for PSA nitrogen production equipment. It uses the principle of pressure swing adsorption (PSA) to separate and produce nitrogen from air. The separation effect of carbon molecular sieves on oxygen and nitrogen in the air is mainly on the different diffusion rates of these two gases on the surface of carbon molecular sieves. Gas molecules with smaller diameters (O2) diffuse faster and more enter the micropores of carbon molecular sieves. Gas molecules with larger diameters (N2) have slower diffusion rates and less entry into the micropores of carbon molecular sieves. It allows for the enrichment of nitrogen components in the gas phase. Therefore, utilizing the characteristic of the difference in adsorption capacity of oxygen and nitrogen by carbon molecular sieves at a certain time. A fully automated control system applies a specific programmable pressure adsorption. And atmospheric pressure analysis cycle process to complete nitrogen oxygen separation and obtain the required high-purity nitrogen gas.

2、 Conditions for controlling nitrogen production from carbon molecular sieves

1. Air compression purification process

It is very necessary for pure raw air to enter the carbon molecular sieve adsorption tower. it is because particles and organic gases entering the adsorption tower will block the micropores of the carbon molecular sieve. And it gradually reduces the separation performance of the carbon molecular sieve. The methods for purifying raw air include: 1. keeping the inlet of the air compressor away from places with oil mist and organic gases. 2. The treated raw air enters the carbon molecular sieve adsorption tower through a refrigerated dryer, adsorbent purification system, etc.

2. Concentration and gas production of product nitrogen

Carbon molecular sieve is to produce nitrogen gas, and its N2 concentration and gas production can adjust according to the needs of the user. When the gas production time and operating pressure determine, reducing the gas production will increase the N2 concentration. Otherwise, the N2 concentration will decrease. Users can adjust according to their actual needs.

3 Equal pressure time

The process of nitrogen production using carbon molecular sieves involves injecting pressurized gas from one adsorption tower into another regenerated adsorption tower from both directions. When the adsorption is completed, ensuring that the gas pressure in both towers is the same. This process is pressure equalization in the adsorption tower. By selecting an appropriate equalization time, energy can recover. And the impact on the molecular sieve in the adsorption tower can reduce, thereby extending the service life of the carbon molecular sieve. The switching speed of the reference valve generally selects with a pressure equalization time of 1-3 seconds.

4. Gas production time

According to the different absorption and diffusion rates of oxygen and nitrogen by carbon molecular sieves, their adsorption of O2 reaches equilibrium in a short period of time. At this time, the adsorption amount of N2 is very small, and a shorter gas production time can effectively improve the gas production rate of carbon molecular sieves. But at the same time, it also increases the operating frequency of valves. Therefore, the performance of valves is also important. Generally, the adsorption time is to be 30-120 seconds. It is to use a short gas production time for small high-purity nitrogen generators, and a long gas production time for large low concentration ones.

5 Operating pressure

Carbon molecular sieves have both dynamic and equilibrium adsorption effects, with high adsorbate partial pressure and adsorption capacity. Therefore, pressurized adsorption is advantageous. However, high adsorption pressure also increases the requirements for the shape of the air compressor. In addition, the adsorption pressure requirements for atmospheric regeneration and vacuum regeneration processes are different. Taking into account various factors, it is better to choose an adsorption pressure of 5-8kg/cm2 for the atmospheric regeneration process. The optimal adsorption pressure for the vacuum regeneration process is 3-5Kg/cm2.

Usage temperature

Choosing a lower adsorption temperature as an adsorbent is beneficial for the performance of carbon molecular sieves. In the nitrogen production process, it is advantageous to lower the adsorption temperature when conditions permit.

If any interests, please feel free to contact our sales team. For more specification details, please visit our website link: https://chempacking.en.alibaba.com/search/product?SearchText=carbon%20molecular%20sieve