Sichuan PSA Technology
Pressure swing adsorption (PSA) is a new type of gas adsorption and separation technology. Its main advantages are: (1) high purity of product; (2) generally it can work at room temperature and low pressure without heating during bed regeneration, saving energy and economy; (3) simple equipment, easy operation and maintenance; (4) continuous circulation operation, fully automatic. Therefore, when this new technology comes out, it has attracted the attention of the industrial circles of various countries, competing for development and research, developing rapidly and becoming more and more mature.
PSA air separation was founded in the early 1960s, and achieved industrial production in the 1970s. Prior to this, the traditional industrial air separation plant mostly used the cryogenic distillation method (hereinafter referred to as the cryogenic method). Since 1980s, the development and utilization of zeolite molecular sieves with high adsorption and separation performance such as CAx and LIX and the improvement of process flow have made the PSA technology develop rapidly. Compared with the cryogenic air separation plant, the PSA process has the advantages of short start-up time, convenient start-up and shutdown, and energy consumption It is characterized by small size, low operation cost, high degree of automation, simple maintenance, small floor area and low civil engineering cost. It is more competitive than cryogenic method in small and medium scale oxygen production without high purity oxygen. It is widely used in electric furnace steelmaking, non-ferrous metal smelting, glass processing, methanol production, carbon black production, chemical fertilizer gasification, chemical oxidation process, pulp bleaching, sewage treatment, biological fermentation, aquaculture, medical and military fields.
Skarstrom put forward PSA patent in 1960. He took 5A zeolite molecular sieve as adsorbent and used a two bed PSA device to separate oxygen rich from air. The process was improved and put into industrial production in 1960s. In the 1980s, the industrial application of PSA technology has made a breakthrough, mainly used in oxygen and nitrogen separation, air drying and purification, hydrogen purification and so on. Among them, the technological progress of oxygen nitrogen separation is to combine the new adsorbent carbon molecular sieve with pressure swing adsorption to separate O and N in the air, so as to obtain nitrogen.
With the improvement of molecular sieve performance and quality, as well as the continuous improvement of PSA process, the purity and recovery rate of the product are constantly improved, which makes PSA based on the economy and the realization of industrialization.