Increasing the efficiency of an air separation plant by varying the cycle stage durations

A mathematical model of a plant for oxygen-enriched air production by pressure swing adsorption is proposed. The model takes into account the experimentally determined actual dependence of the longitudinal dispersion coefficient on the gas velocity and the sorbent particle size. The relationship between the plant efficiency and the duration of each of the operating cycle stages is studied using an ad hoc computer program for numerically solving the model equations. It is shown that optimization of the durations of cycle stages increases the thermodynamic efficiency of the plant to 20–22% in comparison to industrial plants.