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

Other key variables of importance include the following:
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� The emissions assumed to result from the incineration process itself –
incinerators (as with most treatments) are not completely homogeneous. For
example, with regard to NOx emissions (which are a source of secondary
particulates), some countries routinely require use of selective catalytic
reduction of NOx whereas many others do not (yet still may be able to meet
Incineration Directive standards using non-catalytic methods and flue gas
recirculation). Generally, incinerators’ performance needs to be understood in
the context of knowledge of the flue gas cleaning system and of the waste
materials received at the plant;
� the nature of the energy recovery process, and hence the degree to which
offsetting emissions can be attributed to the process. There appears to be a
marked difference in the performance of some Scandinavian facilities, where
the efficiency of heat recovery is very high, and those of the other EU Member
States where energy is usually recovered as electricity, with relatively low
efficiencies. At the same time, it is not entirely clear whether the higher energy
efficiencies possible where heat recovery is the objective should be deemed
more superior from an environmental standpoint since generally, more fuel is
required to generate a kilowatt hour of electricity than is required to generate
a kilowatt hour of heat. Much depends upon the avoided sources of each;
� the degree to which it is assumed that materials are recycled at the facility (for
example, steel and aluminium extracted from bottom ash, or bottom ash
recycled for use as construction material);
� the way in which landfilled residues are treated, particularly the air pollution
control residues which contain hazardous components, and possibly the
bottom ash also if this is also of a hazardous nature.
Another issue which may be important for the analysis – especially if impacts are
being discounted (as they should be) is whether the materials used in the
construction of the plant are included in the analysis. Incinerators are complex pieces
of engineering and they operate for around two decades. Whilst life-cycle studies
suggest a small proportion of overall burdens are associated with materials used in
construction, the application of a non-zero discount rate in a CBA might change this
considerably. Probably of lesser importance are the inputs to the process, including
gas cleaning chemicals.
Of relevance to this discussion is the fact that several countries have instated landfill
taxes in order to try to increase the costs of landfilling so as to drive materials away
from disposal. In theory, this ought to be based upon a view that disposal is ‘worse
than’ recycling. The majority of cost-benefit studies tend to support this perspective
for most dry recyclables. 1152 Interestingly, however, fewer countries have applied
1152 Inger Brisson and Jane Powell (1995) Dump or burn? – the assessment of social costs and
benefits of waste disposal, CSERGE, University College of London and University of East Anglia; J.C.
Powell, David Pearce and Inger Brisson (1995) Valuation for life cycle assessment of waste
management options, CSERGE Working Paper WM 95-07; J.C. Powell, A.L. Craighill, J.P. Parfitt and R.K.
Turner (1996) A lifecycle assessment and economic valuation of recycling, Journal of Environmental
International Review of Waste Policy: Annexes