Review of air quality and plume rise modelling methods for flare emissions.

This paper reviews recent updates in the methods available for source characterisation and dispersion modelling of emissions from flares compared to methods commonly used in Australia and New Zealand in the past. Based on two case studies representing a large refinery flare and a small landfill gas flare, the impact on the predicted downwind pollutant concentrations of using different methods to characterise the sources and to model plume dispersion has been assessed. The impact of using different modelling parameters and modelling approaches on critical plume height (CPH) calculations has also been investigated. The results of the analysis concluded that (a) plume rise statistics extracted from CALPUFF output files provide comparable predictions of CPH to those given by TAPM, and conservative estimates of plume width that potentially better reflect the effects of meteorological conditions, and (b) the Ohio 2018 and Ontario MCEP methods for characterising flare sources give similar predicted downwind pollutant concentrations and plume rise statistics, but modifying the Ohio EPA 2018 method to use source-specific values for radiative heat loss is less conservative. [ABSTRACT FROM AUTHOR]