Page 309 - Materials Chemistry, Second Edition

CAT3525_C09.qxd 2/8/2005 10:11 AM Page 280
280 Waste Management Practices: Municipal, Hazardous, and Industrial

TABLE 9.10
–6
Comparisons of Bioaerosol (10 /m ) and Endotoxin
3
3
(EU/m ) Concentrations Within an RDF Plant
Location Total Bioaerosols a Total Endotoxin a Respirable a
Endotoxin
Floor 0.08 (7) 38.1 (6) 0.70 (7)
Loadout 0.15 (2) 7.81 (2) 3.70 (2)
Lunchroom 0.13 (3) 1.02 (3) 0.89 (3)
Magnetic separator 3.22 (4) 72.0 (4) 12.9 (3)
Processing 0.58 (4) 2.80 (3) 3.09 (4)
a Geometric mean, n
Source: Mahar, S., Waste Manage. Res., 17, 343–346, 1999. Reproduced with
kind permission of the International Solid Waste Association.

2000
1800
1600
1400
1200
SO 2 HCl
ppm 1000

800
600
400
NO x
200
0
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Percent RDF

FIGURE 9.18 Concentration of gaseous SO ,NO , and HCl with varied coal/RDF ratios.
x
2
coal. When increasing proportions of RDF were added to a mixture with Illinois bituminous coal,
the concentrations of atmospheric SO and NO consistently declined (Figure 9.18) (Pichtel, 1991).
x
2
In contrast, total HCl concentrations increased in the flue emissions. These emissions data corre-
lated with fuel compositions.
As is the case with mass-burn incineration of MSW, the production of undesirable gaseous
organic compounds from RDF combustion is of significant concern. A number of studies (U.S.
EPA, 1985a, 1985b; Poslusny et al., 1987; Pichtel, 1991) have demonstrated that the concentrations
of PCDDs and PCDFs have been below detectable limits. Concentrations of PAHs, however, have
been variable. In one study (U.S. EPA, 1985b), large quantities of PAHs were detected in combus-
tion experiments where shredded and pelletized RDF were combusted. Poslusny et al. (1987) found
that naphthalene was the major component of PAH emissions and tetra- and penta-chlorinated
biphenyls were the major components of PCB emissions. In a study by Henstock et al. (1983), con-
centrations of vinyl chloride were in the ppb range.