International Review of Waste Management Policy - Department of ...

63.2.2.2 Landfill of Pre-treated Wastes
Whilst data relating to measurement of trace components in fugitive emissions of
landfill gas from untreated waste is relatively limited, even less research has been
undertaken into those from pre-treated wastes. 1230
Most MBT processes use biofilters (or in limited cases regenerative thermal oxidation
(RTO) techniques) to capture trace components from the exhaust gas produced
during the stabilisation phase. It would seem logical that there will be fewer trace
components emitted through fugitive emissions of gas once the output is resident in
landfill following the pre-treatment process.
Optimized biofilters can remove 50-70% of the total organic content of the waste gas
generated during these processes, although their efficiency is in part determined by
the volume of gas produced. 1231 Typical values for efficiency of compound removal
are shown in Table 63-9.
Table 63-9: Biofilter Efficiencies of MBT Treatment Process
Waste Waste Gas Gas Gas Component Component / / Substance Substance Group Group
Biofilter Biofilter Efficiency Efficiency %
%
Aldehydes 75%
Alkanes 75%
Alcohols 90%
AOX 40%
Aromatic hydrocarbons (benzene) 40%
Aromatic hydrocarbons (toluene, xylene) 80%
NMVOC 83%
PAK, PCB, PCDD/F 40%
Odour 95% - 99%
Ammonia 90%
Source: Binner E (2002) The Impact of Mechanical-Biological Pre-treatment on the Landfill Behaviour
of Solid Wastes, Biological treatment of Biodegradable Waste: Technical aspects, Workshop 8-10 April
2002, Brussels, pp355-372
A reduction in the externalities associated with emissions of the trace elements found
in landfill gas can be expected for pre-treated wastes. Given the lack of data available
for such material, however, we have applied the values in Table 63-8 for both types of
wastes. In this context, we acknowledge that our results will underestimate the overall
reduction in externalities that will occur as a result of treatment of wastes at MBT
facilities.
1230 It should be noted that levels of trace components in landfill gas from untreated wastes are much
lower than in typical emissions from incinerators.
1231 K. Fricke and W. Bidlingmaier (2002) Gaseous and Sewage Emissions in Mechanical-Biological
Rest Waste Treatment, Biological Treatment of Biodegradable Waste: Technical Aspects, Workshop 8-
10 April 2002, Brussels, pp341-354.
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International Review of Waste Policy: Annexes