2.1. Description of the scenarios
Of the 191 million people who lived in Brazil in 2010, the
majority (105 million or 54.75%) lived in municipalities of more
than 100,000 inhabitants [24]. The total population of Brazil is projected
to be 239 million inhabitants in 2030, with 210 million living
in urban areas (87.8%) [24]. In respect to sanitation, 5540 of
the 5570 Brazilian municipalities, regularly collected MSW in
2010. However, 4584 municipalities disposed the MSW in the soil
(a fraction which include any form of inadequate disposal) and
only 936 municipalities treated the MSW, also it must be stressed
that only 16.8% of the municipalities treat and dispose the MSW
properly with recycling and energy recovery [25].
The population of the Brazilian municipalities varies from 805
inhabitants in the smallest ones, to more than 11 millions in the
biggest. Considering that it is impossible to project and evaluate
the economic feasibility of the installation of gasification facilities,
in each one of the 5570 Brazilian municipalities sized to gasify the
total MSW produced daily, in this paper it was convenient to establish
population subgroups or bands. To simplify the analysis, the
total population was divided and clustered into fifteen subgroups
(from A to O) for the economic assessment analysis, as shown in
Table 1.
In each subgroup, the study was conducted over hypothetical
cases, according to the number of inhabitants served by the system
and with a corresponding MSW production rate. Around 80% of the
Brazilian municipalities have less than 30,000 inhabitants (subgroups
A–D); but only 24.5% of the Brazilians live in these municipalities;
75.5% of the Brazilians live in 20% of the remaining
municipalities (subgroups E–O). The most populated Brazilian
municipalities, 20% of the total (subgroups E–O) and produce 75%
of the total Brazilian MSW.