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L1644_C02.fm Page 64 Tuesday, October 21, 2003 3:07 PM

Waste collection Limestone
(Centre of municipalities) Diesel production
production
50 km
9 km

Electricity Electricity
consumed Waste Incineration Plant produced

Water treatment
Cement 4 km
production
16 km
534 km
100 km Ash
Treatment
105 km
Treated ash disposal Slag disposal
Scrap
(Sanitary landfill) (Sanitary landfill) Treatment

FIGURE 2.8 Processes considered in the LCA study within the boundaries of the system
(including transport distances).

treatment companies. The reliability of the data delivered by the compa-
nies depends on the available information and the degree of collaboration.

2.7.3 ASSUMPTIONS AND LIMITATIONS
The principal assumptions are:

• The incineration plant operates 345 days a year and 24 h each day.
• The journey to the destination and the return of the truck are considered
for the analysis of the environmental loads associated with the transport,
assuming the same EL for the empty truck as for the full one.
• The internal consumption of electricity is covered by properly produced
electric energy. The importation of electricity is necessary only in cases
of an operation stop. By this, the environmental loads associated with the
electric energy consumed during the process is the result of the total
inventory analysis (need of iterative computation).
• In the case of scrap-metal treatment, the generated useful product has
been classified as iron within the raw materials.

The main limitations of the study are:

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