Reduction of odours in pilot-scale landfill biocovers

• We documented odour abatement under actual field conditions over several years.
• Combination of dynamic olfactometry and TRS for quantifying odour abatement.
• Important contribution for landfill odour database using dynamic olfactometry.
• Odour data were comparable to odour concentrations from other scientific studies.
• Results using olfactometry and TRS showed very high level of reduction (>95%).

Unpleasant odours generated from waste management facilities represent an environmental and societal concern. This multi-year study documented odour and total reduced sulfur (TRS) abatement in four experimental landfill biocovers installed on the final cover of the Saint-Nicéphore landfill (Canada). Performance was evaluated based on the reduction in odour and TRS concentrations between the raw biogas collected from a dedicated well and the emitted gases at the surface. Odour analyses were carried out by the sensorial technique of olfactometry, whereas TRS analyses followed the pulse fluorescence technique. The large difference of 2–5 orders of magnitude between raw biogas (average odour concentration = 2,100,000 OU m−3) and emitted gases resulted in odour removal efficiencies of close to 100% for all observations. With respect to TRS concentrations, abatement efficiencies were all greater than 95%, with values averaging 21,000 ppb of eq. SO2 in the raw biogas. The influence of water infiltration on odour concentrations was documented and showed that lower odour values were obtained when the 48-h accumulated precipitation prior to sampling was higher.