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                       262                       Waste Management Practices: Municipal, Hazardous, and Industrial

                                   TABLE 9.4
                                   Concentrations of 21 PAH Compounds from the Gaseous
                                   Phase and Particulate Phase in Incinerator Flue Gas
                                   Compound           Gaseous phase  Particulate phase  Total
                                                                                        3
                                                                            3
                                                             3
                                                        (µµg/nm )     (µµg/nm )    (µµg/nm )
                                   Naphthalene          1086            3.61       1090
                                   Acenaphthylene        111            0.689       112
                                   Acenaphthene            3.96         0.228        4.19
                                   Fluorene                4.39         0.079        4.47
                                   Phenanthrene           25.0          0.203       25.4
                                   Anthracene             23.7          0.66        24.4
                                   Fluoranthene            3.77         0.53         4.27
                                   Pyrene                  1.42         1.29         2.71
                                   Cyclopenta[c,d]pyrene   0.003        0.006        0.009
                                   Benz[a]anthracene       0.402        4.65         5.05
                                   Chrysene                0.075        0.544        0.618
                                   Benzo[b]fluoranthene    0.070        0.920        0.989
                                   Benzo[k]fluoranthene    0.170        1.47         1.64
                                   Benzo[e]pyrene          0.684        3.03         3.71
                                   Benzo[a]pyrene          0.754        2.53         3.28
                                   Perylene                0.944        1.85         2.79
                                   Ideno[1,2,3,-c,d]pyrene  0.024       0.055        0.79
                                   Dibenzo[a,h]anthracene  0.306        1.24         1.54
                                   Benzo[b]chrycene        0.069        0.163        0.232
                                   Benzo[ghi]perylene      0.119        0.991        1.11
                                   Coronene                0.461        2.35         2.81
                                   Total PAHs           1260           27.1        1290
                                   Source: Lee, W.J. et al., Atmos. Environ., 36, 781–790, 2002. Reproduced with kind
                                   permission from Elsevier, Oxford, UK.



                          Cadmium is another toxic metal that may be volatilized and therefore mobilized in a mass-burn
                       incinerator. In a study by Zhang et al. (2001), average Cd losses from a laboratory-scale system
                       combusting assorted waste types were 69 and 74% at 850 and 1000°C, respectively. Twenty other
                                                                    o
                       metals were additionally lost to the atmosphere. At 500 C, Sn was emitted; at 850°C K, Mg, Na,
                       Bi, Cr, Ge, Li, Pb, Sn, Tl, and Zn were lost, and nine more metals, Al, Be, Cs, Nb, Sb, Sr, Th, Y,
                       and Zr were lost at 1000°C. It was speculated that the released metals were transferred to the com-
                       bustion flue gas mainly in the forms of metallic chloride compounds, e.g., CdCl , SnCl , SnCl ,
                                                                                         2     4     2
                       ZnCl , and PbCl . No significant losses for Ca, Fe, Ag, Ba, Co, Cu, Ga, Hf, Mn, Mo, Ni, Rb, Sc,
                           2        2
                       Ta, Ti, U, V, and W were reported. Transformations of inorganic substances during MSW combus-
                       tion are depicted in Figure 9.8.
                          Several studies have been conducted on the effects of atmospheric emissions from MSW incin-
                       erators on local soils and plants. For example, Kukkonen and Raunemma (1984) found that the con-
                       centrations of Br, Ca, Cl, Cr, Fe, Ni, Pb, Si, Ti, V, and Zn on birch leaf samples showed a strong
                       inverse correlation with distance from a MSW incinerator in Finland. Fewer elements showed this
                       relationship when grass was sampled.


                       9.4.8 AESTHETICS
                       Noise is inevitable during MSW incineration. Waste collection vehicles, processing equipment, the
                       combustion process itself, air pollution control (e.g., operation of pumps), and production of steam
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