Page 75 - Materials Chemistry, Second Edition

Life Cycle Assessment: Principles, Practice and Prospects
62

Sorting and Separated Existing Avoided
Waste separation recyclable reprocessing material
generation Bin1 technology fraction credits
in Victoria
Bin 2 Application of Benefits and
Organics
Household processing organic avoided
separation Transport product fertiliser use
and
Bin 3 collection
Residual
waste
Bin 4 Landfill
management
processing
Avoided
Generation of energy
energy production
credits
System boundary for study
Management
of incineration
residuals
Figure 6.9 System boundary for the LCA of waste and resource recovery options (including
waste-to-energy).

2003). This time, the system boundaries were expanded to investigate other kerbside waste
streams and different waste treatment technologies. The findings from this study would assist
in the development of Victoria’s solid waste strategy: Towards Zero Waste. Activities in landfill
were modelled on a more detailed level to include methane generation from degrading organic
material and the creation of carbon sinks from non-degradation. This introduced a new level
of complexity and insight into the role of waste generation in the economy. To reduce the
greenhouse gas profile of different waste stream fractions, this study revealed some interesting
findings that challenged policy makers who had the task of defining appropriate waste treat-
ments and guiding waste management.
Since 2000, there has been substantial development and diversification of waste treatment
technologies dealing with residual and organic waste fractions. Such technologies provide
outcomes such as energy production, useful organic material, volume reduction and stabilisa-
tion of organic fractions and/or toxins (Grant et al. 2003). In light of these developments, there
was a need to evaluate the overall environmental impacts of emerging waste treatment tech-
nologies in a full life cycle context so that effects on other aspects of the waste stream and
waste management system could be investigated. The study aimed to provide a transparent
environmental evaluation of a range of waste management technologies for dealing with mixed
waste and organic waste in the Victorian waste stream.
The system boundary for the study is presented in Figure 6.9. Fifteen waste management
configurations in four basic groups (A–D) were examined, presented in Table 6.3. The technol-
ogy descriptions and key assumptions are presented in Table 6.4.
The environmental indicators included in the study were based on the indicator set devel-
oped by the Centre for Environmental Studies (CML) in the Netherlands (Guinee et al. 2001).
They were:
s global warming
s resource depletion
s eutrophication
s photochemical oxidation

100804•Life Cycle Assessment 5pp.indd 62 17/02/09 12:46:17 PM