What is pressure swing adsorption (PSA) separation technology? What is the basic principle behind using PSA technology for oxygen production?

Thread Content

What is Pressure Swing Adsorption (PSA) separation technology? What is the basic principle behind using PSA technology for oxygen production? Over the past decade, Pressure Swing Adsorption (PSA) air separation technology, as a representative of non-cryogenic methods, has increasingly shown its competitiveness due to its unique advantages. It has gradually made its way into industries such as chemicals, metallurgy, papermaking, and environmental protection. In particular, it is likely to completely replace traditional methods in the production of medical oxygen. PSA technology is a new gas separation technique that finds extensive applications in the fields of gas separation, purification, and cleaning. For example, producing oxygen and nitrogen from air, separating carbon dioxide and methane from fermentation gases, and separating and purifying hydrogen from mixed gases. Among them, the process of separating oxygen and nitrogen from air using PSA technology is the most notable and has seen the fastest development. Adsorption refers to the phenomenon in which, when a gaseous substance and a solid substance form an adsorption system, the components at the phase interface accumulate (concentrate) ； Desorption refers to the process by which gas molecules that have been adsorbed return to the gas phase. At the two-phase interface, the substance that is adsorbed is called the adsorbate, while the adsorbing phase is called the adsorbent. PSA technology, simply put, refers to a cyclic process of adsorption under pressure and desorption under reduced pressure under isothermal conditions. The basic principle of producing oxygen using PSA technology is as follows: Using air as the raw material and zeolite molecular sieves as adsorbents, under normal temperature and pressure conditions, the property that zeolite molecular sieves increase their adsorption capacity for nitrogen (the adsorbate) when under pressure and decrease this capacity when under reduced pressure is utilized to create a rapid cycle of pressure-driven adsorption and pressure-reduced desorption. This process enables the separation of oxygen from nitrogen in air, thereby producing oxygen.