Conditions That Need to Be Controlled for Carbon Molecular Sieve Nitrogen Production
1. The conditions for nitrogen production by carbon molecular sieve – air compression purification process.
It is necessary to ensure the pure feed air flow into the carbon molecular sieve adsorption column, because particles and organic atmosphere into the adsorption column will block the micropores of the carbon molecular sieve, and gradually reduce its separation performance.
The methods of purifying feed air show as follows:
(1) Keep the air inlet of the air compressor away from the places with dust, oil mist or organic atmosphere.
(2) Passing through the cold dryer, adsorbent purification system and other devices, the feed air flow into the carbon molecular sieve adsorption column after the final treatment.
2. The conditions for nitrogen production by carbon molecular sieve – the concentration and productivity of the nitrogen products.
To produce nitrogen by , the N2 concentration and gas production can be randomly adjusted according to the requirements of the user. While the time of gas production and operative pressure are definitive, reducing the gas production will make N2 concentration increase, vice versa.
3. The conditions for nitrogen production by carbon molecular sieve – Grading time
In the process of nitrogen production by carbon molecular sieve, when the adsorption is done, the pressurized gas inside the adsorption column can be drawn upward or downward into another regenerated adsorption column, ensuring the same gas pressure in the two columns. This process is called grading of adsorption columns. Selecting appropriate grading time, namely, the recyclable energy, also can ease the burden of the molecular sieve inside the column so that the lifecycle of the carbon molecular sieve. The reference to the switching speed of the valve is 1-3 seconds of grading time.
4. The conditions for nitrogen production by carbon molecular sieve – gas production time
The adsorption and diffusion rate of the carbon molecular sieve towards oxygen and nitrogen is different. The O2 adsorption balance can be achieved in a short period of time, while the amount of N2 adsorption is small. Some short gas production time can effectively enhance the gas production of the carbon molecular sieve, in the same time, but the action frequency of the valve is also improved. Thus the performance of the valve also matters. Generally, the adsorption time will be controlled in 30-120 seconds. It is recommended that small high-purity nitrogen generators set short gas production time and the large set longer time.
5. The conditions for nitrogen production by carbon molecular sieve – operating pressure
The carbon molecular sieve has the kinetic effect as well as the balanced adsorption effect. While the partial pressure of adsorbate is high, the adsorption capacity will be high. It shows that pressure adding adsorption is beneficial, but the higher adsorption pressure requires strict selection of air compressor. In addition, the regeneration under the atmospheric pressure or in the vacuum requires different adsorption pressure. Considering all factors, it is recommended that the adsorption pressure for the process of regeneration under the atmospheric pressure should be properly set at 5-8 Kg/cm2 and 3-5kg/cm2 in the vacuum.
6. The conditions for nitrogen production by carbon molecular sieve – temperature
As for the adsorbent, adopting a lower adsorption temperature will be conducive to the functioning of the carbon molecular sieve performance. If possible, it is advantageous that choose a lower adsorption temperature in the nitrogen generator craftwork.
