Suzhou Evergrande Purification Equipment Co., Ltd.

      PSA pressure swing adsorption nitrogen production principle

      Carbon molecular sieve can simultaneously adsorb oxygen and nitrogen in the air, and its adsorption capacity also increases with the increase of pressure, and there is no significant difference in the equilibrium adsorption capacity of oxygen and nitrogen under the same pressure. Therefore, it is difficult to complete the effective separation of oxygen and nitrogen only by the change of pressure. If the adsorption rate is further considered, the adsorption characteristics of oxygen and nitrogen can be effectively distinguished. The diameter of oxygen molecules is smaller than that of nitrogen molecules, so the diffusion rate is hundreds of times faster than that of nitrogen, so carbon molecular sieves absorb oxygen very quickly, and the adsorption reaches more than 90% in about 1 minute; at this time, the adsorption capacity of nitrogen is only 5%. So the adsorption is mostly oxygen at this time, and the rest is mostly nitrogen. In this way, if the adsorption time is controlled within 1 minute, oxygen and nitrogen can be initially separated, that is to say, adsorption and desorption are realized by pressure difference, adsorption when the pressure increases, and desorption when the pressure decreases. The difference between oxygen and nitrogen depends on the speed difference between the two being adsorbed, which is achieved by controlling the adsorption time. The time is controlled very short, oxygen has been fully adsorbed, and nitrogen has not yet been adsorbed, and the adsorption process is stopped. Therefore, the pressure swing adsorption nitrogen production must have a pressure change, and the time should be controlled within 1 minute.