BIOSOLIDS ODOUR PREDICTION MODELS: SENSORY AND ANALYTICAL MEASUREMENT APPROACHES
Sirapong Vilalai 1, Steven A. Gabriel 1, Christopher Peot 2 , and Mark Ramirez 2
1Department of Civil & Environmental Engineering, University of Maryland, College Park,
Maryland, USA
2 District of Columbia Water and Sewer Authority, Washington, DC, USA
(free)
Biosolids are being beneficially recycled for agricultural purpose. Often, however, biosolids
odours diminish marketability of biosolids, bring community opposition or, in the worst case, result
in a ban on the biosolids land application program. This study is aimed to develop practical
biosolids odour predicting models using the existing data available at the wastewater treatment
plant that can be applied for biosolids management on daily basis. The operational parameters,
such as sludge blanket level, number of centrifuge running, sludge blending ratio, etc. as well as
the characteristics of sludge in the sludge blending system including temperature, pH, oxidation
Reduction Potential, and H 2 S emission were collected to find parameters prone to biosolids
odour production. Biosolids odour data were collected by two odour measurement techniques:
analytical odour measurement using H 2 S analyzer and sensory odour measurement using
human odour panel. Both odour measurement techniques were applied to biosolids odour
samples collected from the solids handling process at Blue Plains advance wastewater
treatments plants in Washington DC. Two biosolids odour predicting models are presented in this
paper based on summer and non-summer seasons. Biosolids producer can use the biosolids
odour prediction models to early detect and notify the hauling contractor when malodourous
biosolids are anticipated. As a result, malodourous products can be allocated accordingly to the
appropriate sites in preventing the odour complaints from the communities.
KEYWORDS
Biosolids odour prediction model, sensory and analytical measurement.
