Comparing Static Headspace and Dynamic Flux Hood Measurements of Biosolids Odour Emissions

• Published in: Chemical engineering transactions 2016-01, Vol.54
• Main Authors: R. Fisher, R. Barczak, J.P. Alvarez Gaitan, R. Stuetz
• Format: Article
• Language: English
• ISSN: 2283-9216
• DOI: 10.3303/CET1654008

Malodorous emissions from biosolids limit opportunities for their reuse. Potential emissions may be measured from the headspace of samples or dynamic emissions swept from surface of samples using hood methods. The static headspace method is widely used to represent potential emissions from heaped anaerobic piles of biosolids, whilst dynamic flux hoods measure potential ambient emissions from the surface of biosolids piles taking into account some dilution. Methods were compared using replicates of different biosolid samples to highlight differences between the potential odour measurements. The resultant odorants emitted from the samples as they were aged were analysed using TD-GC-SCD/NCD. Whilst the different methods showed similar behavior of emissions as they were aged, the odorant concentrations varied dramatically between methods. A greater variety of volatile sulfur compounds (VSCs) were observed using the headspace method, perhaps due to the higher concentrations typical of the headspace method exceeding the analytical equipment’s limit of detection. VSC emissions using the static headspace method were seen to decrease after the initial days of storage until they were undetectable. The ongoing VSCs emitted from aged biosolids, using the dynamic flux hood method, is likely due to the interplay between anaerobic and aerobic conditions. The differences between the two methodologies identified the need to understand the suitability of measurement methods.