Energetic, exergetic and economic assessment of oxygen production from two columns cryogenic air separation unit

Oxygen is one of the important industrial gases indubitably. Industrial operations take advantage of the reactive properties of oxygen in order to manufacture products as efficient and cost-effective as possible. Oxygen is involved in most industrial processes in which combustion or chemical reactions play a role (from steelmaking to water treatment). Distillation of air (air separation) is currently the most commonly used technique for production of pure oxygen and nitrogen on an industrial scale. In this article, energetic, exergetic and economic assessments of two columns cryogenic air separation are considered. For this purpose, a two columns cryogenic air separation unit is simulated. Then using simulation data, energetic and exergetic and economic analyses are performed. Annualized cost of system is chosen as an economic approach. Sensitivity analyses of economic parameters against utility prices and cost of product in the market are investigated. Results of exergy analysis show that the compression and distillation units with 34.48 and 52.89 percent of total exergy destruction are the main exergy destructive components respectively. It also shows that in the current economic condition, the suggested system is economically feasible in the size of 9 kg/sec O-2 and more than it. (C) 2015 Elsevier Ltd. All rights reserved.