Modeling of H₂S Dispersion in Brazil with Aermod: Case Study of Water Resource Recovery Facility In South of Brazil

Modelagem da Dispersão de H₂S no Brasil com Aermod: Estudo de Caso em Estação de Recuperação de Recursos Hídricos no Sul do Brasil

Abstract

Water Resource Recovery Facility (WRRF) can be source of odorous gases. We analyzed the emission and dispersion of hydrogen sulfide gas (H₂S), odor indicator, produced during the anaerobic treatment of wastewaters, using WATER9 and AERMOD models for two distinct events: August 2013 and February-March 2014. Data from two WRRF in Brazil were used to feed the model and a statistical data validation was performed, followed by an evaluation of model results regarding H₂S emission and dispersion. Daily peak events and averages over the two periods were calculated. Results show a good performance from the model in comparison to the observations. Moreover, odor plumes typically reached 2-4 km from their sources and they may be strongly affected by atmospheric stability/instability conditions in the events analyzed and, in general, only the residences at the vicinity of WRRF were affected by the pollutant odor. Finally, the methodology presented showed to be feasible and realistic for purposes of WRRF planning and management.

Keywords:
H₂S; hydrogen sulfide; odor plume; sewer system; numerical modeling