Modelling botanical biofiltration of indoor air streams contaminated by volatile organic compounds

• Published in: Journal of hazardous materials Vol. 422; p. 126875
• Main Authors: Masi, Matteo, Nissim, Werther Guidi, Pandolfi, Camilla, Azzarello, Elisa, Mancuso, Stefano
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-01-2022
• Subjects: Air Pollutants - analysis; Air Pollution, Indoor - analysis; Biodegradation, Environmental; Botanical biofilter; Filtration; Global sensitivity analysis; Indoor air quality; Reactive transport modelling; Volatile organic compounds; Volatile Organic Compounds - analysis; Volatile organic compounds; Global sensitivity analysis; Botanical biofilter; Reactive transport modelling; Indoor air quality
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.126875

Botanical filtration is a biological-based treatment method suitable for removing hazardous volatile organic compounds (VOCs) from air streams, based on forcing an air flow through a porous substrate and foliage of a living botanical compartment. The pathways and removal mechanisms during VOC bioremediation have been largely investigated; however, their mathematical representation is well established only for the non-botanical components of the system. In this study, we evaluated the applicability of such a modelling scheme to systems which include a botanical compartment. We implemented a one-dimensional numerical model and performed a global sensitivity analysis to measure the input parameters influence on the transient and steady biofilter responses. We found that the most sensitive parameters on the transient-state behaviour were the mass transfer coefficient between gas and solid surfaces, and the fraction of solid surfaces covered by the biofilm; the steady-state response was primarily influenced by the biofilm specific surface area and the fraction of surfaces covered by the biofilm. We calibrated the identified set of parameters and successfully validated the model against data from a pilot-scale installation. The results showed that the application of the model to systems with a botanical compartment is feasible, although under a strict set of assumptions.
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•VOC transport and biochemical reactions in flow-through botanical bioreactor are modelled.•Global sensitivity analysis identifies the model output sensitivity to input parameters.•Model is validated against pilot-scale botanical biofiltration experimental data.