Eco design LCA of an innovative lab scale plant for the production of oxygen-enriched air. Comparison between economic and environmental assessment

Abstract

Here we developed an early-stage attributional LCA of an innovative production process of oxygen-enriched air by water desorption. We compared LCA's results with a rigorous economic model, in an eco-design optimization perspective. We developed the life cycle analysis using primary data from the lab-scale plant. We used SimaPro 8.1.1.16 for the LCA analysis and the ReCiPe Endpoint V 1.12 E/A method for the interpretation of the results. The functional unit was the amount of enriched air produced by the plant in 24 h in Milano (Italy). A steady state chemical plant simulation software (PRO/II 9.3) calculated the reference flow and we input it in SimaPro with a parametric function. We considered a “cradle-to-grave” analysis. Temperature, pressure and water flowrate were varied to minimize environmental burdens and plant costs. Uncertainty analysis revealed that there is no difference between operating the degassing unit at 20 °C or 30 °C. SimaPro and PRO/II presented different optimum conditions. However, taken as a whole, we individuated the best process parameters from an eco-economic prospective. The results obtained are related to a lab-scale plant and thus no comparisons between industrial processes are possible, but the methodology we propose will improve the design of any process.