Environmental Engineering Reference
In-Depth Information
400000
0.6
0.5
line 1
300000
0.4
line 2
200000
0.3
line 1
0.2
100000
0.1
line 2
0
0
0.01
0.1
1
10
0.01
0.1
1
10
D
p
[
µ
m]
D
p
[
µ
m]
Fig. 3.16 Size distribution of stack nanoparticles in the municipal waste incineration plant in
Piacenza (Italy)
emissions, the nanoparticle contribution resulted from MSW incineration plants is
small [
62
].
Hazardous Waste Incineration
Hazardous waste is eliminated under specific regulations that are meant to guaran-
tee the reduction to a minimum of direct emissions, through VOC or other forms of
volatile or particulate waste release and stack emissions [
66
,
67
].
Current norms regarding hazardous waste incineration require strict limits both
for PM
2.5
emissions and indirect nanoparticle emissions under the form of heavy
metals which are more or less volatile at high temperatures (Table
3.11
)[
62
,
67
].
Although incineration of any type of waste has a small contribution to anthro-
pogenic nanoparticle emissions [
62
-
65
,
67
], there are studies that attempt at finding
a direct correspondence between thermal waste elimination and the statistical
parameters of population health (Fig.
3.17
)[
68
,
69
].
According to these sources, waste incineration plants produce huge amounts of
fine and ultrafine particles, because the current standard value of PM emissions
(10 mg/m
3
) specifies a filter retention rate of only 5-30 % for PM
2.5
and 0 (zero) for
PM
1
. In fact, most stack emissions are ultrafine particles of the most dangerous
type. Fabric filters with Teflon membrane are not effective against particles under
200-300 nm which are very harmful to health [
69
]. In this case, what matters is the
particle number and size, and not their weight [
65
,
68
].
The distribution of particle size by weight will cause great errors, especially in
hazardous waste incinerators with equipment for reducing nitrogen oxides, which
may actually double the PM
2.5
emissions [
69
,
70
].
