A comprehensive study for improving the working parameters for the design of a PSA-based oxygen concentrator

Oxygen concentrators (OC) are medical devices that supply oxygen by separating nitrogen from the atmospheric air. The functionality of PSA-based OC majorly depends on internal pressure dynamics, cycle timing accuracy, orifice dimensioning for flow and pressure regulation, selection of zeolite, air moisture content, and others. This study aimed to develop an improved OC with sustainable performance by optimizing these key parameters. Initially, lithium and sodium-based zeolite adsorbents were experimentally compared, and it was determined that lithium-based 13X zeolite with particle size 0.4-0.8 mm is more effective for OC. An optimization study was performed for the orifice diameter for the required flow rate, purity, and pressure. The 1 mm hole diameter orifice was concluded to deliver the most optimal functionality. The results were validated via analytical and numerical study, which can further be interpolated for higher flow rate OC. After investigation, it was concluded that filters having zeolite with 10%-15% alumina would effectively remove moisture from the air for sustainable OC. An intensive experimental study was conducted to evaluate the cycle timing under optimum operating circumstances, and it was determined that the overall cycle timing is 12-14 s, with flushing accounting for 5%-8% and recharging accounting for 8%-10% of production time. The research developed 10 LPM OC with 95% purity, a recovery rate of 38.46%, and a BSF of 57.2 kgs/TPDO2. Later, the OC was certified by an ISO-13485 prototyping facility and tested in various hospitals, followed by commercialization. The system's performance was found to be superior to that of other commercialized products.