Environmental and Economic Assessment of Electrothermal Swing Adsorption of Air Emissions from Sheet-Foam Production Compared to Conventional Abatement Techniques.

Abstract

A life-cycle assessment (LCA) and cost analysis are presented comparing the environmental and economic impacts of using regenerative thermal oxidizer (RTO), granular activated carbon (GAC), and activated carbon fiber cloth (ACFC) systems to treat gaseous emissions from sheet-foam production. The ACFC system has the lowest operational energy consumption (i.e., 19.2, 8.7, and 3.4 TJ/year at a full-scale facility for RTO, GAC, and ACFC systems, respectively). The GAC system has the smallest environmental impacts across most impact categories for the use of electricity from select states in the United States that produce sheet foam. Monte Carlo simulations indicate the GAC and ACFC systems perform similarly (within one standard deviation) for seven of nine environmental impact categories considered and have lower impacts than the RTO for every category for the use of natural gas to produce electricity. The GAC and ACFC systems recover adequate isobutane to pay for themselves through chemical-consumption offsets, whereas the net present value of the RTO is $4.1 M (20 years, $0.001/m(3) treated). The adsorption systems are more environmentally and economically competitive than the RTO due to recovered isobutane for the production process and are recommended for resource recovery from (and treatment of) sheet-foam-production exhaust gas. Research targets for these adsorption systems should focus on increasing adsorptive capacity and saturation of GAC systems and decreasing electricity and N2 consumption of ACFC systems.