Formation and emission status of PCDDS/PCDFS in municipal solid waste incinerators in korea

Article abstract of DOI:10.1016/S0045-6535(00)00423-9

This study was carried out to examine the formation and the emission status of polychlorinated dibenzo-p-dioxins/ polychlorinated dibenzofurans (PCDDs/PCDFs) in the flue gases of commercial-scale municipal solid waste (MSW) incinerators, and thus to provi

Full text of DOI:10.1016/S0045-6535(00)00423-9

Chemosphere 43 )2001) 701±707
Formation and emission status of PCDDs/PCDFs in municipal
solid waste incinerators in Korea
a,
a
a
a
Sam-Cwan Kim *, Sung-Hwan Jeon , Il-RokJung , Ki-Heon Kim ,
a
Myung-Hee Kwon , Jae-Hyung Kim , Jun-Heung Yi , Seung-Jin Kim ,
a
b
b
b
Jae-Cheon You , Dong-Hee Jung
b
a
NIER ꢀNational Institute of Environmental Research), Environmental Research Complex, Kyungseo-Dong,
Seo-Ku, Inchon, 404-170, South Korea
Analytical Research Center, Environmental Management Co., Mt. 26-4, Hasanwon-Dong, Boondang-Ku, Kyonggi-Do, South Korea
b
Abstract
This study was carried out to examine the formation and the emission status of polychlorinated dibenzo-p-dioxins/
polychlorinated dibenzofurans )PCDDs/PCDFs) in the ¯ue gases of commercial-scale municipal solid waste )MSW)
incinerators, and thus to provide the engineering data for the reduction of PCDDs/PCDFs emitted from MSW in-
cinerators. The formation concentrations of the PCDDs/PCDFs generated at the outlet of waste heat boilers )WHB)
were in the range of 1.18±29.61 ng-TEQ/N m3 )average 5.75 ng-TEQ/N m3), while the emission concentrations at the
stacks were in the range of 0.026±4.548 ng-TEQ/N m3 )average 0.924 ng-TEQ/N m3). Two major 2,3,7,8-substituted
congeners were 2,3,4,7,8-PeCDF and 2,3,4,6,7,8-HxCDF, and their concentrations were up to 50% and 64% of total
TEQ values at the outlet of WHB and the stack, respectively. From the results of multi-regression analysis, the for-
mation concentration of PCDDs/PCDFs could be predicted as follows with the correlation factor of r2 ˆ 0:962:
PCDDs/PCDFs )ng-TEQ/N m3† ˆ 3:036 ꢀCl† ‡ 0:094 ꢀT1† À 0:472 ꢀCombustibles† ‡ 0:059 ꢀCO† À 0:039 ꢀTHC† À
3:366 ꢀH† ‡ 22:157, where T1 ꢀ°C† is the temperature at the outlet of the WHB. Cl, Combustibles and H are given as
percentages and the others are in parts per million. Ó 2001 Elsevier Science Ltd. All rights reserved.
Keywords: Municipal solid waste incinerator; Waste heat boiler; Stack; Flue gas; PCDDs/PCDFs; Formation; Emission; Multi-
regression analysis
1. Introduction
increased. Accordingly, the government has enforced a
series of countermeasures such as the enactment of 0.1
ng-TEQ/N m3 PCDDs/PCDFs emission standards
)Ministry of Environment, Republic of Korea, 1999),
management guidelines, ®nancial assistance for the re-
pair of incineration facilities, technical assistance for
good combustion practice )GCP), designation of dioxin
analysis agencies, etc. Through such a dioxin-control
policy, the generation and emission concentrations of
PCDDs/PCDFs at the MSW incinerators have been
reduced. In this study, the formation and emission status
of PCDDs/PCDFs at commercial-scale MSW incinera-
tors with treatment capacity of above 200 ton/day were
investigated through the year 1998 to provide the
As of 1998, the incineration rate of municipal solid
waste )MSW) incinerators in Korea was recorded to be
about 5%. It will be increased up to about 15% in the
year 2001 due to the lackof available land®ll sites
)Ministry of Environment, Republic of Korea, 1998).
However, the incineration-favored policy has faced
the dioxin-emission problem as the construction activi-
ties of further commercial-scale incineration facilities are
* Corresponding author.
E-mail address: kscnier@me.go.kr )S.-C. Kim).
0045-6535/01/$ - see front matter Ó 2001 Elsevier Science Ltd. All rights reserved.
PII: S 0 0 4 5 - 6 5 3 5 ) 0 0 ) 0 0 4 2 3 - 9

702
S.-C. Kim et al. / Chemosphere 43 ꢀ2001) 701±707
engineering data for reducing PCDDs/PCDFs emitted
from MSW incinerators.
heating value )LHV) of the MSW were, on average, only
2,129 kcal/kg and 1,661 kcal/kg, respectively, although
the average carbon value was 46% of the MSW.
The formation concentrations of PCDDs/PCDFs
generated at the outlets of the WHBs were in the range
of 1.18±29.61 ng-TEQ/N m3 )average 5.75 ng-TEQ/
N m3) )Table 3), and the emission concentrations at the
stacks were in the range of 0.026±4.548 ng-TEQ/N m3
)average 0.924 ng-TEQ/N m3) )Table 4). Congener
pro®les of 2,3,7,8-substituted congeners as TEQ values
followed almost the same pattern in both formation and
emission cases; the penta- and hexa-CDFs recorded the
relatively higher TEQ values than the other 2,3,7,8-
substituted congeners at similar ratios )Figs. 1 and 2).
Two major 2,3,7,8-substituted congeners were 2,3,4,7,8-
PeCDF and 2,3,4,6,7,8-HxCDF, and their TEQ values
were 50% and 64% of the total TEQ values at the outlets
of the WHB and the stack, respectively. The formation
and the emission concentrations of PCDFs were about
three and ®ve times higher TEQ values than those of
PCDDs, respectively; the formation and the emission
ratios of PCDFs to PCDDs were 78:22 and 84:16, re-
spectively. From the results of multi-regression analysis,
the formation concentration of PCDDs/PCDFs could be
2. Material and methods
A total of nine commercial-scale MSW incinerators
with treatment capacity of above 200 ton/day were se-
lected to determine the characteristics of MSW before
incineration and the formation and the emission con-
centrations of PCDDs/PCDFs during incineration.
About two tons of MSW were analyzed every weekfor
the past three years at the nine incineration sites in order
to determine the density, the physical components, the
calori®c value and the elemental composition. PCDD/
PCDF samplings were performed three times on each
incineration site at the outlets of the WHBs and the
stacks, simultaneously.
The Korean standard testing method for dioxins and
furans )Ministry of Environment, Republic of Korea,
1996) was used for sampling, pretreatment and analysis.
The concentrations of PCDDs/PCDFs were determined
by high-resolution gas chromatography/high-resolution
mass spectrometry )HRGC/HRMS: Micromass, Auto-
spec Ultima) above 10,000 resolution with an SP-2331
column. Operation conditions of the HRGC/HRMS
during PCDDs/PCDFs analysis are given in Table 1.
Toxic equivalents as 2,3,7,8-TeCDD )TEQ) were calcu-
lated by using international toxicity equivalency factors
)I-TEF).
predicted as follows with
a correlation factor of
r2 ˆ 0:962: PCDDs/PCDFs )ng-TEQ/N m3† ˆ 3:036
ꢀCl† ‡0:094 ꢀT1† À0:472 ꢀCombustibles† ‡ 0:059 ꢀCO†
À0:039 ꢀTHC† À 3:366 ꢀH† ‡ 22:157, where T1 ꢀ °C† is
the temperature at the outlet of the WHB )Fig. 3). The
unit of Cl, Combustibles and H is percent, and the
others are in parts per million.
3. Results
4. Discussion
As shown in Table 2, the moisture content of the
MSW incinerated in Korea was 56% )w/w) on average
)Kim, 1998). The major source of moisture in the MSW
was food waste, which was one of three major physical
components )food, paper, and plastics). The moisture
content of food waste was as high as 67% with an av-
erage of 50% )w/w) in the MSW to total MSW. Con-
sequently, the high heating value )HHV) and the low
The low quality of the MSW, which had high mois-
ture content and low calori®c value, resulted in low in-
cineration temperature and high generation of
pollutants. Also, a lot of supplemental fuel was required
to increase the inside furnace temperature and reduce
pollutant generation. For better and cost-e€ective com-
bustion of such a low-quality MSW, the recommended
Table 1
GC/MS analytical condition of PCDDs/PCDFs
Parameters
PCDDs/PCDFs
Injector
Column
Oven
250°C
SP-2331 )60 m  0:32 mm ID  0:2 lm)
120°C )3 min) ! 10°C/min to 200°C )3 min) ! 3°C/min to 265°C )15 min)
Carrier gas
Ionization
Ion source
Resolution
Monitoring
He, 2.5 ml/min
EI, 36 eV
270°C
>10,000
4 Function, SIM )selected ion monitoring)

S.-C. Kim et al. / Chemosphere 43 ꢀ2001) 701±707
703
Table 2
Characteristics of MSW incinerated in Koreaa
Parameters
Incinerator
HWD
DD
CW
ID
MD
JD
SS
PC
SK
Mean
0.37
Density )ton/m3)
0.36
0.46
0.30
0.39
0.46
0.30
0.40
0.24
0.45
Moisture )%)
Combustibles )%)
Ash )%)
65.90
29.61
4.49
62.61
32.59
4.80
54.65
36.83
8.52
55.13
34.42
10.45
48.70
38.79
12.51
48.17
41.38
10.45
48.61
43.43
7.96
65.74
28.57
5.69
55.75
38.81
5.44
56.14
36.05
7.81
Total )%)
100
100
100
100
100
100
100
100
100
100
Plastics )%)
Paper )%)
Food )%)
10.70
13.20
67.00
1.90
18.30
12.50
51.90
1.05
15.12
22.59
42.87
3.55
13.79
17.18
58.52
2.82
14.69
30.90
31.25
8.51
27.85
19.60
44.51
0.84
14.45
19.27
50.23
6.88
9.36
17.23
60.85
3.62
13.66
29.11
41.70
6.58
15.32
20.18
49.87
3.97
Wood )%)
Textile )%)
Metals )%)
Non-metals )%)
Total )%)
2.60
2.30
12.45
2.02
1.78
3.96
3.55
3.90
1.23
4.12
5.00
1.21
3.15
4.58
2.01
3.40
2.01
5.49
0.53
4.63
2.42
2.30
8.36
2.56
5.53
2.84
2.58
3.53
2.93
3.60
100
100
100
100
100
100
100
100
100
100
HHV )kcal/kg)
LHV )kcal/kg)
1,649
1,146
1,818
1,312
2,165
1,689
1,972
1,523
2,189
1,774
2,996
2,542
2,363
1,918
1,705
1,216
2,306
1,831
2,129
1,661
C )%)
H )%)
O )%)
47.50
6.68
38.93
1.77
0.30
0.33
4.49
100
45.82
50.70
54.50
38.91
47.59
44.38
40.47
44.21
46.01
7.34
37.73
1.50
0.22
2.59
4.80
7.45
30.36
1.98
0.30
0.69
8.52
6.35
25.19
2.60
5.91
38.15
1.24
7.41
30.18
1.74
6.88
36.91
2.08
0.20
1.59
7.96
6.14
40.79
2.28
0.24
4.40
5.69
6.61
39.93
1.42
0.09
2.29
5.44
6.75
35.35
1.85
0.26
1.97
7.84
N )%)
S )%)
0.30
0.61
0.43
2.86
0.23
2.40
Cl )%)
Ash )%)
Total )%)
10.45
12.51
10.45
100
100
100
100
100
100
100
100
100
a Note: HHV ± high heating value; LHV ± low heating value.
approach was to reduce the moisture content and make
the quality and the size of MSW homogenized and
uniform prior to supplying the MSW to the furnace for
reaching a stable combustion condition.
Addinkand Olie, 1995; Karase,k 1995; Huang and
Buekens, 1995; Thuꢀ and Herzschuh, 1995; Olie et al.,
1998) between PCDDs/PCDFs and some parameters
such as CO, SO2, O2, H2O, chlorine, etc. Huang and
Buekens )1995) indicated that such terms as O2, HCl,
F.A. )¯y ash), SO2 and CO had the possibility of par-
ticipating in dioxin formation reaction as a result of
multiple regression analysis. However, Thuꢀ and Herz-
schuh )1995) indicated that the correlation between
PCDDs/PCDFs and CO is not signi®cant or at least
weaker than that between PCDDs/PCDFs and other
aromatic compounds. As a consequence of this investi-
gation, it could be deduced that the formation concen-
tration of PCDDs/PCDFs had low correlation with
most of variables, but had positive correlation with Cl
content of MSW, temperature at the outlet of WHB and
CO concentration in the ¯ue gas.
During the investigation, the formation concentra-
tion of PCDDs/PCDFs in PC incinerator was recorded
to be ®ve times higher than the average of 5.748 ng-
TEQ/N m3 in 1998. Thus, the generation status of
PCDDs/PCDFs in the furnace of PC incinerator was
investigated in 1999.
The result showed that PCDDs/PCDFs at the outlet
of furnace were generated in the range of 0.31±1.71 ng-
TEQ/N m3 )average 1.001 ng-TEQ/N m3 )Jung et al.,
1999). If one compared these furnace-outlet results of
1999 to the WHB-outlet results of 1998, it could be
guessed that PCDDs/PCDFs were severely synthesized
in the WHB when the ¯ue gas was cooled down.
Meanwhile, multi-variable regression analysis was
performed to predict the formation concentration of
PCDDs/PCDFs at the outlet of the WHB with the 50 or
more variables such as physico-chemical properties of
the MSW incinerated, operation parameters of inciner-
ator, ®rst and second air rate supplied, and the others
related to incineration. Of course, there are some con-
troversies on the correlation )Finkelstein et al., 1990;
5. Conclusion
·
The formation concentrations of PCDDs/PCDFs
generated at the outlets of waste heat boilers were in
the range of 1.18±29.61 ng-TEQ/N m3 )average 5.75
ng-TEQ/N m3), while the emission concentrations

Table 3
Formation concentrations of PCDDs/PCDFs at the outlet of the WHBs in MSW incinerators
2,3,7,8-Substituted congeners
)ng-TEQ/N m3)
Incinerator
MD
CW
PC
0.583
HWD
DD
SK
JD
SS
IS
Mean
)%)
3.04
1
2
3
4
5
6
7
2,3,7,8-TCDD
0.029
0.085
0.018
0.100
0.043
0.080
0.018
0.373
0.079
0.089
0.012
0.024
0.019
0.018
0.006
0.247
0.040
0.071
0.019
0.055
0.030
0.041
0.009
0.265
0.028
0.091
0.031
0.084
0.041
0.060
0.009
0.344
0.433
0.693
0.123
0.360
0.259
0.278
0.075
2.221
0.038
0.065
0.017
0.066
0.033
0.047
0.016
0.282
0.159
0.336
0.072
0.081
0.108
0.124
0.025
0.905
0.186
0.285
0.048
0.098
0.071
0.082
0.016
0.786
0.175
0.365
0.088
0.254
0.157
0.188
0.042
1.269
1,2,3,7,8-PeCDD
1,2,3,4,7,8-HxCDD
1,2,3,6,7,8-HxCDD
1,2,3,7,8,9-HxCDD
1,2,3,4,6,7,8-HpCDD
OCDD
1.569
0.457
1.420
0.809
0.958
0.210
6.006
6.35
1.54
4.42
2.73
3.26
0.74
22.09
Total PCDDs
8
9
2,3,7,8-TCDF
0.030
0.034
0.854
0.162
0.308
0.734
0.078
0.223
0.059
0.042
2.524
0.048
0.031
0.461
0.066
0.139
0.139
0.024
0.068
0.007
0.004
0.987
0.495
0.597
11.074
1.667
2.823
4.438
0.580
1.515
0.277
0.136
23.598
0.058
0.021
0.499
0.053
0.118
0.117
0.016
0.031
0.005
0.001
0.919
0.050
0.032
0.886
0.106
0.198
0.199
0.015
0.053
0.007
0.001
1.547
0.122
0.098
1.621
0.252
0.539
0.511
0.086
0.238
0.033
0.010
3.510
0.024
0.027
0.541
0.094
0.191
0.336
0.050
0.119
0.026
0.013
1.421
0.127
0.069
1.909
0.199
0.476
0.690
0.076
0.207
0.039
0.015
3.807
0.135
0.054
0.967
0.125
0.278
0.270
0.035
0.097
0.017
0.007
1.985
0.121
0.107
2.090
0.303
0.563
0.826
0.107
0.283
0.052
0.025
4.478
2.11
1.86
1,2,3,7,8-PeCDF
2,3,4,7,8-PeCDF
1,2,3,4,7,8-HxCDF
1,2,3,6,7,8-HxCDF
2,3,4,6,7,8-HxCDF
1,2,3,7,8,9-HxCDF
1,2,3,4,6,7,8-HpCDF
1,2,3,4,7,8,9-HpCDF
OCDF
10
11
12
13
14
15
16
17
36.37
5.27
9.80
14.37
1.86
4.93
0.91
0.44
Total PCDFs
77.91
Total PCDDs/PCDFs
2.894
1.232
29.610
1.183
1.892
5.732
1.701
4.713
2.771
5.748
100.00

Table 4
Emission concentrations of PCDDs/PCDFs at the stacks of MSW incinerators
2,3,7,8-substituted congeners
)ng-TEQ/N m3)
Incinerator
MD
CW
PC
HWD
DD
SK
JD
SS
IS
Mean
%
1
2
3
4
5
6
7
2,3,7,8-TCDD
0.002
0.004
0.001
0.002
0.002
0.001
0.000
0.012
0.003
0.002
0.000
0.001
0.001
0.001
0.000
0.009
0.011
0.025
0.006
0.018
0.009
0.012
0.002
0.084
0.007
0.030
0.010
0.024
0.017
0.017
0.002
0.107
0.002
0.005
0.001
0.003
0.002
0.003
0.000
0.015
0.005
0.008
0.001
0.003
0.002
0.001
0.000
0.021
0.084
0.234
0.043
0.132
0.061
0.035
0.004
0.592
0.036
0.137
0.031
0.070
0.040
0.040
0.008
0.362
0.027
0.036
0.007
0.015
0.008
0.014
0.004
0.111
0.020
0.053
0.011
0.030
0.016
0.014
0.002
0.146
2.14
5.78
1.21
3.23
1.70
1.48
0.25
1,2,3,7,8-PeCDD
1,2,3,4,7,8-HxCDD
1,2,3,6,7,8-HxCDD
1,2,3,7,8,9-HxCDD
1,2,3,4,6,7,8-HpCDD
OCDD
Total PCDDs
15.79
8
9
2,3,7,8-TCDF
0.000
0.000
0.007
0.001
0.002
0.002
0.001
0.000
0.000
0.000
0.014
0.001
0.001
0.010
0.001
0.003
0.003
0.000
0.001
0.000
0.000
0.020
0.011
0.008
0.164
0.019
0.044
0.074
0.009
0.019
0.002
0.000
0.350
0.006
0.004
0.129
0.016
0.036
0.041
0.006
0.011
0.002
0.000
0.252
0.002
0.001
0.027
0.004
0.009
0.008
0.001
0.003
0.000
0.000
0.056
0.004
0.002
0.039
0.003
0.007
0.009
0.001
0.002
0.000
0.000
0.068
0.063
0.064
2.137
0.131
0.371
1.056
0.049
0.072
0.011
0.002
3.956
0.006
0.018
0.788
0.067
0.194
0.399
0.025
0.071
0.010
0.002
1.580
0.025
0.013
0.271
0.039
0.097
0.175
0.019
0.051
0.012
0.007
0.709
0.013
0.012
0.397
0.031
0.085
0.196
0.012
0.026
0.004
0.001
0.778
1.43
1.33
1,2,3,7,8-PeCDF
2,3,4,7,8-PeCDF
1,2,3,4,7,8-HxCDF
1,2,3,6,7,8-HxCDF
2,3,4,6,7,8-HxCDF
1,2,3,7,8,9-HxCDF
1,2,3,4,6,7,8-HpCDF
1,2,3,4,7,8,9-HpCDF
OCDF
10
11
12
13
14
15
16
17
42.95
3.39
9.17
21.22
1.34
2.78
0.47
0.15
Total PCDFs
84.21
Total PCDDs/PCDFs
0.026
0.029
0.434
0.359
0.070
0.088
4.548
1.942
0.820
0.924
100

706
S.-C. Kim et al. / Chemosphere 43 ꢀ2001) 701±707
Fig. 1. Congener pro®le of 2,3,7,8-PCDDs/PCDFs at the outlet of the WHB.
Fig. 2. Congener pro®le of 2,3,7,8-PCDDs/PCDFs at the stacks of MSW incinerators.
Fig. 3. Comparison of formation concentration measured and predicted at the outlet of the WHB.

S.-C. Kim et al. / Chemosphere 43 ꢀ2001) 701±707
707
enzofurans in heterogeneous systems. Environmental Sci-
ence and Technology 29 )6), 1425±1435.
at the stacks were in the range of 0.026±4.548 ng-
TEQ/N m3 )average 0.924 ng-TEQ/N m3).
Finkelstein, A., Klicius, R., Hay, D., 1990. The national
incinerator testing and evaluation program )NITEP) mass-
burning technology assessment. In: Clement, R., Kagel, R.
)Eds.), Emissions from Combustion Process: Origin, Mea-
surement, Control. Lewis Publishers, pp. 243±256.
Huang, H., Buekens, A., 1995. Analyzing dioxin measurement
data in municipal waste incineration using multiple regres-
sion analysis. Organohalogen Compounds 23, 455±460.
Jung, I.-R., Shin, C.-K., Kim, S.-C., et al., 1999. A study on the
enactment for the structure and performance evaluation of
MSW incineration facility )II), NIER No. 99-14-529.
Karasek, F.W., 1995. An overview of dioxin formation in
combustion processes. Organohalogen Compounds 23, 315±
317.
·
·
Two major 2,3,7,8-substituted congeners were
2,3,4,7,8-PeCDF and 2,3,4,6,7,8-HxCDF, the TEQ
values of which were 50% and 64% of the total values
at the outlet of the WHB and the stack, respectively.
As a result of multi-regression analysis, the formation
concentration of PCDDs/PCDFs at the outlet of
WHB could be predicted with a correlation factor of
r2 ˆ 0:962 as follows: PCDDs/PCDFs )ng-TEQ/
N m3† ˆ 3:036 ꢀCl† ‡ 0:094 ꢀT1† À 0:472 )Combusti-
bles) ‡ 0:059ꢀCO†À0:039ꢀTHC†À3:366ꢀH†‡22:157,
where T1 ꢀ°C† is the temperature at the outlet of the
WHB, and the unit of Cl, Combustibles and H is per-
cent and the others are in parts per million.
Kim, S.-C., et al., 1998. A study on removal eciencies of
PCDDs/PCDFs by APCDs in commercial-scale of MSW
incinerators. NIER.
·
The formation concentration of PCDDs/PCDFs had
positive correlation with Cl content of MSW, temper-
ature )°C) at the outlet of WHB and CO concentra-
tion in the ¯ue gas.
Ministry of Environment, Republic of Korea, 1996. The
Korean standard testing method for dioxins and furans.
Ministry of Environment, Republic of Korea, 1998. Environ-
mental White Book, 486 pp.
Ministry of Environment, Republic of Korea, 1999. Waste
Management Act, 162 pp.
Acknowledgements
Olie, K., Addink, R., Schoonenboom, M., 1998. Metal as
catalysts during the formation and decomposition of
chlorinated dioxins and furans in incineration processes.
Jounal of the Air and Waste Management Association 48,
101±105.
We thankthe director, Ko Yoon-Hwa, and the
deputy director, Yang Jae-Moon, Ministry of Environ-
ment in Korea, for the budget assistance for this project.
Thuû, U., Herzschuh, R., 1995. PCDD/F in ¯ue gas in bottom
ash of lignite deomestic combustion and the role of the salt
content of the burned briquettes. Organohalogen Com-
pounds 23, 471±476.
References
Addink, R., Olie, K., 1995. Mechanisms of formation and
destruction of polychlorinated dibenzo-p-dioxins and dib-