Estimation of nanoparticle emissions in indoor industrial environments using a grey-box modeling approach

Estimating nanoparticle emission rates from industrial activities is essential for developing quantitative risk assessment tools and prediction models for indoor air quality and occupational exposure. However, determining them is challenging, particularly for incidentally generated nanoparticles (IN...

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Detalles Bibliográficos
Autores: Cebolla Alemany, Joaquim|||0000-0002-3958-6913, Macarulla Martí, Marcel|||0000-0002-5469-7291, Viana Rodríguez, Mar, Gassó Domingo, Santiago|||0000-0003-0481-4522, Moreno Martín, Verónica, Bou Ibañez, David, San Félix Forner, Vicenta
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/430594
Acceso en línea:https://hdl.handle.net/2117/430594
https://dx.doi.org/10.1016/j.buildenv.2025.113169
Access Level:acceso abierto
Palabra clave:Indoor aerosol
Emission rate
Exposure modeling assessment
Stochastic models
Thermal spraying
Àrees temàtiques de la UPC::Edificació::Instal·lacions i acondicionament d'edificis::Instal·lacions de ventilació
Àrees temàtiques de la UPC::Física::Física de fluids
Descripción
Sumario:Estimating nanoparticle emission rates from industrial activities is essential for developing quantitative risk assessment tools and prediction models for indoor air quality and occupational exposure. However, determining them is challenging, particularly for incidentally generated nanoparticles (INPs), due to their calculation from concentration measurements in complex environments with polluted backgrounds. This study addresses the challenges of defining INP emission rates by proposing a reduced-order grey-box modeling approach. The method was tested in three industrial scenarios with different thermal spraying activities, evaluating 78 models based on mass-balance aerosol concentration equations. Convergence tests, statistical analyses, and physical feasibility studies revealed that 33 % of the models met all criteria. The simplest models, incorporating forced ventilation and particle generation while excluding natural diffusion, aggregation, and deposition, demonstrated the best performance and robustness, with two models reaching a 100 % successful performance on six applied datasets. Emission rates for the monitored processes were of similar magnitude, with minor variations around 4 × 1015 particles/min attributed to the materials and component morphology. Estimated ventilation airflow rates also aligned with the expected slight underperformance of the extraction systems between 1 and 22 × 107 cm3/min depending on the monitored booth and the ventilation configuration, showing air change per hour rates within the 39–105 h-1 range. The findings highlight that grey-box modeling combined with model reduction through lumped sum parameters provides a systematic and reliable approach to estimating INP emissions. This method could inform new standard procedures. Future research should apply this approach to diverse industrial activities and exposure applications.