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

62.0 Life-cycle Assessment of Residual Waste
Treatment Technologies
This section carries out a life cycle assessment of a range of residual waste treatment
technologies, using the Environment Agency’s tool WRATE. The assessment is
described in Section 62.1. Limitations of the LCA approach in general (as exemplified
by the WRATE analysis) are described in Section 62.2.
62.1 Life-cycle Assessment Using WRATE
A recently published report produced by Fehily Timoney & Company (FTC), Veolia and
Ramboll sought to investigate the role that the Mechanical Biological Treatment of
waste might play within the Irish waste management sector. 1188 Their report included
an environmental impact appraisal which used the life-cycle tool WRATE to assess
these impacts. Their appraisal indicated that the thermal treatment scenario which
included the recovery of both heat and electricity performed the best against the six
assessment criteria considered within WRATE’s default assessment method.
However, their analysis also briefly considered results obtained using the full range of
MBT processes included within the software. The latter assessment concluded that
there was considerable relative variability between the different MBT systems.
The approach taken within the current appraisal is to examine in more detail the
variation seen in the results of the impact assessments indicated by WRATE for a
range of MBT and incineration options. In addition, Eunomia holds an Expert License
for the software, which provides additional functionality with regard to analysis of
impacts at each of the process stages. This enables the identification of specific
pollutants or chemicals causing the impact at each stage of the treatment process,
within each of the impact assessments.
Our modelling uses the default impact assessment methods included within the
model. We have made the following core assumptions across all treatments
considered within the appraisal:
964
� We have used the residual waste composition data recently produced by RPS
for the EPA; 1189
� The baseline fuel mix is based on the 2007 mix for Ireland; we have separately
defined the marginal electricity source as a modern combined-cycle gas
turbine (CCGT, reflecting the carbon intensity of the new build of electricity
generation sources). Whilst the former is used when calculating impacts
1188 Fehily Timoney & Company / Veolia Environmental Services / Ramboll (2008) Critical Analysis of
the Potential for Mechanical Biological Treatment for Irish Waste Management: Volume 2, Research
Report, Report for the Environmental Protection Agency, September 2008.
1189 RPS (2009) Municipal Waste Characterisation Surveys 2008, Report for the EPA, March 2009.
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