Selection issues for cryogenic pressure swing adsorption
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If: You want to expand the scale of your business and install air separation equipment, what will you use to convince customers who are currently using cryogenic air separation systems to switch to pressure swing adsorption? Requirement: Oxygen is not to be considered. Last edited by super1 on 2008-1-19 08:05.]
I discussed this matter with Mr. Zhang from the north yesterday; he believes that PSA is a good option for oxygen production rates of 20,000 cubic feet per hour or less. Personally, I think that if only oxygen-enriched air or pure nitrogen is used, PSA can be applied; whereas if both oxygen and nitrogen are required, cryogenic methods would be better (with a capacity of over 10,000 cubic meters per hour). The choice should be based on the specific process requirements, as there is no one-size-fits-all solution. Am I correct?
In fact, no matter which separation method is used, there is a range for which it is suitable; for example, deep cooling is better for separating oxygen in large volumes, while PSA is sufficient for smaller volumes. This also depends on the state of the oxygen product, and another important factor is the range of oxygen concentration in the oxygen to be separated
Users with a high level of management skill don’t need to be persuaded at all; they will conduct their own research and make decisions after analyzing and comparing various options. They will choose what is best for them based on their own circumstances, and they won’t easily give up their principles just because of sales pitches, unless they have no understanding of the technology at all and simply believe whatever others say is good. Hehe
Oxygen seems to be a viable option, while nitrogen is generally used as a shielding gas, with purity requirements typically on the PPM level
Use the fast startup time of pressure swing adsorption to attract users who don’t have high requirements for nitrogen purity, right?
What matters for the operation of equipment is stability; startup time is just a minor factor. Cryogenic air separation systems can maintain stability for 1 to 2 years
What is the power consumption per unit of nitrogen produced by your pressure swing adsorption system? What is the output pressure? The twin-tower process for nitrogen production can now achieve an electricity consumption of 0.2 KWH/NM3, with a pressure of over 1 kg/cm2 and a purity of 3 ppm. No specific comparisons have been made yet. For an air separation unit with a capacity of 800 NM3/hr, the equipment investment is estimated to be around 3.5 million yuan (imported compressors are used). Indeed, air separation plants no longer rely on the piston compressors that were commonly used in the past; there is no oil present in the air, and it’s easy for the distillation towers to operate continuously for more than 2 years. When it is said that the startup time is short, this mainly refers to cold startup after a short power outage. Pressure swing adsorption can be started in about 10 minutes, whereas cryogenic methods see an increase in time required as the power outage lasts longer; in this regard, pressure swing adsorption has a certain advantage.