Abstract:
Container fumigation is frequently undertaken for quarantine and pre-shipment purposes. The process ensures that a commodity is free from pest and disease prior to export or import. Due to the hazardous nature of the chemicals used (such as methyl bromide and phosphine), physical air emission controls such as carbon filtration are required to minimise air quality impacts. This may involve locating containers in a large mechanically ventilated enclosure, which is not always practical, particularly where large volumes of containers require storage and fumigation.
Alternative solutions may be required at times in lieu of fumigant recapture.
This paper looks at the development of a venting management procedure for restricting the number of shipping containers being vented at any given time, based on prevailing wind conditions. Air dispersion modelling was undertaken using CALPUFF for a range of meteorological conditions (including wind speed, wind direction and stability class) and the maximum number of containers that can be vented under specific wind conditions was identified. From this information, a venting management chart was developed that could be used by the site operator (in conjunction with real-time meteorological data) to determine the number of shipping containers that can be vented, while maintaining compliance with the relevant ambient air quality goals.
Authors: Samuel Wong
Keywords: methyl bromide, fumigation, air quality impacts, emissions management, air dispersion
modelling
Presented at: Clean Air Society of Australia and New Zealand (CASANZ)’s International Clean Air and Environment Conference, September 2022
