Life Cycle Assessments of Energy From Solid Waste (PDF)

1.3 Aim and scope of present study
The overall aim of the present study is to evaluate different strategies for treatment of solid
waste based on a life-cycle perspective. Important goals are to identify advantages and
disadvantages of different methods for treatment of solid waste, and to identify critical factors
in the systems, including the background systems, which may significantly influence the
results. The results are intended to be used by decision-makers in local, regional and national
authorities and industries as one basis for decisions on strategies and policies for waste
management and investments for new waste treatment facilities. Some aspects of the scope
are:
• The focus is on Swedish conditions, but it is expected that much of the results will be of
interest also for other countries
• The intended use is for assessing effects of different strategic choices made today or the
coming years. These effects will however prevail for decades since the lifetime of the
investments will be comparatively long. The time frame of the treatment systems is
therefore extended from the current situation to several decades into the future.
• Included in the study are fractions of municipal solid waste, which are combustible and
recyclable or compostable.
• The focus is on energy use and climate change although other impact categories such as
acidification, eutrophication, photo-oxidant formation and human and ecotoxicological
impacts are also considered.
The scope of the study is further defined in section 2.3.
1.4 Some guidance to the reader
In chapter 2, LCA methodology is presented and discussed. Section 2.1 is a general
presentation of LCA methodology and can be skipped by those familiar to LCA. Section 2.2
contains a discussion on some methodological issues of special relevance for LCA of waste
management systems. Section 2.3 includes a presentation of methodological choices made in
this study and it is probably of importance for any reader who wants to have something more
than just a quick feeling of the report. The methodological choices made for the impact
assessment are partly described in section 2.3 and in more detail in chapter 6. Section 2.4
contains a description of the LCA software programme that is used.
Chapter 3 contains a description of the scenarios used in this study (one base scenario and
several “what-if scenarios”) and some major assumptions. At the end of the chapter there is a
summary which may be enough to read for some readers of this report.
Chapter 4 contains detailed descriptions of the waste materials studied and the amounts of
them. Chapter 5 contains detailed descriptions of the processes included in the study. Many
readers are probably not interested in all the details of these chapters.
Chapter 7 contains a fairly detailed presentation of the results of all scenarios. Many readers
may not be interested in all the details of this chapter and may look at some of the tables and
go directly to chapter 8, using chapter 7 as a reference for aspects of particular interest.
Appendix 1 includes data on additives, energy and transports used in this study, which are
mentioned in chapter 5 but not described in detail there. Appendix 1 is included in this report.
Appendix 2-7 are available as separate reports, see preface for details on contents.
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