Modelling of the Dispersion of atmospheric pollutants is today a routine method in environmental air quality management. In the particular case of environmental odour emissions, dispersion models have become indispensable given the difficulty of obtaining a reliable value of odour concentration in immision.
The use of dispersion models helps in the prediction of the impacts on air quality from industrial emission at their sources and it is a valuable argument to propose effective control strategies.
It is also important to consider that the cost of a model usually increases with its complexity and necessary computational resources, as follows:
Eulerian model >> Lagrangian model >> Gaussian model
There is a tendency to label the quality of the models according to their complexity. This sometimes causes errors in the choice of dispersion model, since such a choice should be based on the adequacy of the model to the case study. From this point of view, a model based on the gaussian solution could be sufficient to solve a complex problem and vice versa, an eulerian model may not be adequate for a simple study. The key is to align the selection criteria and validate methods and results.
The most common dispersion model found in the scientific literature are the lagrangian models CALPUFF and AUSTAL2000g. The Environment Agency of England and Wales has published an interesting guide on the choice of dispersion models for odour predictions, but it only discusses pros and cons of the gaussian models ADMS or AERMOD, tagging these models as "advanced" as compared to ISC model. This guideline does not have many references to lagrangian models.
Notes
- Nice guide book edited by the UK environmental agency: Review of Dispersion Modelling for Odour Predictions
- A Slovakian group that works with the model fluidyn-panache, an eulerian model.
- In the links section there are other interesting models.
Links
- Revision of Regulatory Dispersion Models, an Important Key in Environmental Odour Management
- CALPUFF website is now owned by Exponent
- A new CALPUFF update by the US EPA recently published
- Review of Dispersion Modelling for Odour Predictions. Using science to create a better place, Environment Agency Uk, 2007.
