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

kg kg 1,4-dichlorobenzene 1,4-dichlorobenzene eq.
eq.
Life-cycle methodology involves the compilation of a life-cycle inventory, detailing all
direct and indirect emissions (the latter relating to avoided impacts associated with
energy generation and recycling). Each life-cycle assessment method assigns a series
of characterisation factors (or weightings) to each of the substances in the inventory,
according to their relative anticipated impact within the method. In some cases the
different impact assessment methods give quite different results for the same type of
impact, through the use of different characterisation factors against the data
contained within the same emissions inventory.
An example of this is shown in Table 62-4 and Table 62-5. These figures compare the
results obtained using two different impact assessment methods within WRATE to
measure the terrestrial eco-toxicity of waste treatment technologies treating one
tonne of residual waste. They show that whilst the CHP technologies perform
relatively favourably against this criterion when assessed using the Impact 2002
method, they do not fare well when the CML method is used to assess the same
criterion.
Further evidence of this can be seen when considering an assessment of the human
toxicity associated with the different treatment technologies. Table 62-6 shows the
results obtained using the Impact 2002. This method indicates the Arrowbio ADbased
MBT plant as the most favourable treatment option with respect to human
toxicity impacts, whilst the Billingham incinerator performs the worst against this
criterion in this method. In contrast, the HTP Inf Method outlined in Section 62.1.1.3
suggests that the Chineham incinerator is the most favourable treatment option,
whilst the Arrowbio AD-based MBT plant performs less well in comparison to the
Generic AD plant.
Table 62-4: Terrestrial Eco-toxicity Assessed using the CML Method
0.6
0.5
0.4
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
974
29/09/09
0.0132
0.174
0.468
Landfill Ecodeco MBT Generic Aero
MBT
0.358
Generic AD
MBT
AD Arrowbio
MBT
-0.182
0.0284
0.502
0.217
0.179
0.389
Incin Elec C Incin Elec D Incin Elec B Incin CHP C Incin CHP G