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

of a thermal efficiency of 84% and an electrical efficiency of 35%. These are
optimistic in the context of efficiencies currently achieved and are likely to be
deliverable only at large operating scales. The Draft BREF note gave no case where
the net export of electricity exceeded 18%. 1240 A survey of 25 incinerators across
Europe generating electricity only reported a maximum gross energy efficiency of
27.9% with a weighted mean efficiency of 21.8% across the 25 facilities (the mean
net efficiency was given as 17.7%). 1241 The current analysis uses a gross efficiency of
27%, reflecting the top end of the range quoted by ERM and the CEWEP survey.
N2O emissions are modelled based on previous research undertaken by Eunomia on
behalf of WRAP. 1242 The considerable uncertainty with respect to these emissions is
acknowledged within the EU BREF note, which provided a range of 5.5 – 66 g N2O per
tonne of waste treated by the facility. We use the mid point of these values within the
current analysis. CH4 emissions are negligible from incineration facilities.
The efficiency with which metals are recovered from incineration facilities is modelled
based on a survey of Dutch facilities. 1243
Table 63-11 summarises the assumptions for incineration discussed previously.
Table 63-11: Assumptions for Incineration
Parameter Parameter Parameter
Assumption
Assumption
Gross electrical generation efficiency 27%
Electricity demand for flue gas cleaning 78 kWh / t input
Diesel use by process 4.7 l / t input
Use of natural gas by process 7.2 m 3 / t input
Recycling of bottom ash 50%
CH4 emissions from process 0 kg CH4 / t
N2O emissions from process 0.04 kg N2O / t
Recovery rate for ferrous metals 70%
Recovery rate for non-ferrous metals 30%
1240 European Commission (2005) Integrated Pollution Prevention and Control, Draft Reference
Document on the Best Available Techniques for Waste Incineration, Final Draft, May 2005.
1241 I. Riemann (2006) CEWEP Energy Report (Status 2001-2004): Results of Specific Data for Energy,
Efficiency Rates and Coefficients, Plant Efficiency Factors and NCV of 97 European W-t-E Plants and
Determination of the Main Energy Results, updated July 2006.
1242 Eunomia (2007) Emissions of Nitrous Oxide from Waste Treatment Processes, Report to WRAP,
July 2007.
1243 L. Muchova and P. Rem (2008) Wet or Dry Separation: Management of Bottom Ash in Europe,
Waste Management World Magazine, 9(3).
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International Review of Waste Policy: Annexes