Polychlorinated dibenzo-p-dioxins and dibenzofurans in flue gas emissions from municipal solid waste

1296Chen et al. / J Zhejiang Univ SciA 2008 9():1296-1303Journal of Zhejiang University SCIENCE AISSN 1673 565X (Print); ISSN 1862-1775 (Online)www. zju.edu.cn/jzus; www.springerlink.comJzusE-mail: jzus@zju.edu.cnPolychlorinated dibenzo-p-dioxins and dibenzofurans in flue gasemissions from municipal solid waste incinerators in ChinaTong CHENt", Yue-ing GU', Jian-hua YAN', Xiao-dong LI', Sheng-yong LU', Hui-fen DAI, Ke-fa CEN'('State Key Laboratory of Clean Energy Uiliation, Zhejiang University, Hangzhou 310027, China)(Schoo of Medicine, Zhejiang Universin, Hangzhou 310058, China)Received Dec. 24, 2007; revision acepted June 10, 2008Abstract: Polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) emissions in flue gas from two types of municipal solidnerators (MSWIs) most commonly used in China were investigated in this study. The selected incinerators include twograte-type MSWIs: MSWI-A (350 t/d) and MSWI-B (150 t/d), and two fluidized bed MSWIs: MSWI-C (400 /d) and MSWI-D(400 t/d), which are all equipped with semi-dry lime scrubber and bag filter except MSWI-D equipped with cyclone and wetscrubber (WS) as air pollutant control device (APCD). Results indicated that the emission concentration and the international toxicequivalents (I-TEQs) of the PCDD/Fs from the stacks were in the range of 1.210~10.273 ng/Nm' and 0.019~0.201 ng I-TEQ/Nm',respectively. They were greatly lower than the emission regulation standard of PCDD/Fs in China (1.0 ng I-TEQNm). However,only the PCDD/Fs emission level from MSWIC was below 0.1 ng I-TEQ/Nm'. Although the homologue profiles were distinct,the contributions of the 2,3,7,8-subsituted congeners to the total I-TEQ were similar among all the investigated MSWIs. Twomajor 2,3,7,8-substituted congeners, 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDD, account for 47% and 9% (average values) of the totalI-TEQ values, respectively. The correlation between PCDD/Fs levels and composition of flue gas was also discussed.Key words: Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), Municipal solid waste incinerator (MSWI), Grate,Fluidized beddoi: 10.163 ljzus.A0720144Document code: ACLC number: X5; X7INTRODUCTION .veloped cities and its total capacity had been 13155 twaste per day by July 2002 (Zhu et al, 2005) becauseWith the rapid development of economy and of its advantages including signifcant volume reduc-great improvement of living standards in China, a tion (~90%), mass reduction (~ 70%), toxicity reduc-large amount of municipal solid waste (MSW) is tion, and energy recovery (Yan et al, 2006).generated, which reached to about 136.38 millionIn 1988, the first MSWI, a Martin grate importedtons in 2002 and keeps going up at a rate of8%~ 10% from Mitsubishi Co., Japan, was built in Shenzhen,per year (Li et al, 2004; Zhu et al, 2005). For dis- China. Since then, more MSWI plants have beenposing these MSW, three approaches, i.e, landfill,constructed in Beijing, Shanghai, Guangzhou andcompost and incineration are applied in China. Among other big cities. Up to now, more than 140 MSWIthem, though landfill is the dominant one, which plants are in operation or under construction (Bie etaccounts for more than 80% of the MSW disposal(Li al, 2007). Three incineration technologies, ie, grate,et al, 2004), the amount of large-scale MSW incin- fluidized bed and rotary kiln, are now used in China,erator (MSWI) plants is growing, especially in de-and the grate and fluidized bed type boilers contrib-uted more than 80% of the total incinerators.Project supported by the Natural Science Foundation of ZhejiangAlthough MSWI has many advantages, manyProvince (No. X206955), Zhejiang Medical and Health ResearchFund (No. 2007A047) and the Education Bureau of Zhejiang Prov-pollutants, sucl中国煤化工especiallyince (No. N20080181), ChinapolychlorinatedenzofuransTYHCNMHG.Chen et al. / J Zhejiang Univ SciA 2008 9():1296-13031297(PCDD/Fs) are emitted during the incineration proc- while MSWI-D is equipped with cyclone and wetess. A preliminary investigation on PCDD/Fs emis- scrubber (WS) as air pollutant control device (APCD).sion from flue gas of over 15 typical incineration AIll sampling points are located downstream to APCD.facilities has shown that half of them exceeded 1.0 Schematic of PCDD/Fs sampling system is shown ininternational toxic equivalents (I-TEQs) ng/Nm’ at Fig.l. This sampling system was based on US EPA11% (v/v) O2, the standard of PCDD/Fs emission Method 0023A (1996). Sampling volume is ap-regulation in China (Tian and Ouyang, 2003). In this proximately 2~4 Nm'. All samplings were repeatedstudy, two grate-type incinerators and two fluidized once. The PCDD/Fs surrogate standards were addedbed incinerators (FBIs) were investigated for to the XAD-2 resin for checking the PCDD/Fs sam-PCDD/Fs emission. The study aimed to determine thepling efficiency. After each sampling,characteristic of PCDD/Fs distribution profiles in rinsed with acetone and toluene, respectively, and thedifferent types of MSWIs in China. The relationship rinse was saved in brown glass bottle. Filter andbetween PCDD/Fs levels and compositions of flue XAD-2 resin also stored and maintained in dark be-gas was discussed. Furthermore, the suggestions on low 4 °C on field until transferred to the laboratory.the control technology of PCDD/Fs in commer-cial-scale MSWI plants were presented.PCDD/Fs analysisPretreatment of PCDD/Fs in the collected fluegas was conducted according to the US EPA MethodEXPERIMENTS1613B (1994). The sample was spiked with knownamounts of 13C-labelled internal standards, thenSamplingSoxhlet extracted with toluene for 24 h. After extrac-Table 1 briefly lists the spec of the investigated tion the sample was macro-concentrated by rotaryMSWI. MSWI-A, MSWI-B and MSWI-C are all evaporator to 1~2 ml, and then the sample extractsequipped with semi-dry lime scrubber and bag filter were exchanged into hexane. Sample clean upTable 1 Spec of the investigated MSWIIncineratorFurmace typeCapacity (td)Fuel typeAir pollutant control deviceMSWI-A Hydraulic ladder mechanical grateSemi-dry lime scrubber+bag filterMSWI-B Martin grateI 50MSWMSWI-C Fluidized bed400Coal/MSW=20/80 Semi-dry lime scrubber+bag filterMSWI-D Fluidized bedCoal/MSW=28/72 Cyclone+wet scrubberNote: activated carbon was used to remove PCDD/Fs in the fue gas produced from MSWI-A and MSWI-BFilter :CondenserXAD-2 resinNozzleProbeTo isokineticcontrol consoleFlue gasRecirculationImpingerpumpFig.1 Schematic of system for PCDD/Fs sampling fr中国煤化工.YHCNMH G.1298Chen et al. / J Zhejiang Univ SciA 2008 9():1296-1303procedures involved a multi-silica gel column and aTable 2 PCDD/Fs concentration in the flue gas (standardbasic-alumina column. The elute was concentrateddry gas at 11% (V/v) O2)again and blown with nitrogen to approximately 20 μul.Concentration (ngNm3)TEQ valueBefore analysis the "'C-labelled injection standardsIncineratorPCDDS PCDFs Total(ng I-TEQ/Nm’)were added to the sample for calculating the recovery2.42.04.40.20of I'C-labelled intermal standards. All solvents wereMSWI-A3.26.29.40.17purchased from Mallinckrodt Baker Inc., USA and2.21.26.40.11MSWI-Bwere pesticide residue analysis grade. The analysis2.9 2.85.80.078was performed by HRGC/HRMS on a 6890 Series0.750.871.0.026MSWI-Cgas chromatograph (Agilent, USA) and coupled to a0.019JMS-800D mass spectrometer (JEOL, Japan). AMSWID2.12.74.80.072DB-5 ms fused-silica capillary column (60 mx0.254.110.00.16mm inside diameter, 0.25 um film thickness) wasNote: two sampling were done for each MSWIused. The temperature program was as follows: 150°C, held for 1 min; increased at a rate of 25 °C/min toAmong all MSWIs investigated, the emission190 °C; then increased at a rate of 3 °C/min to 280 °C，levels of PCDD/Fs from MSWI-C were the lowest.held for 20 min. The carrier gas was helium at a con- MSWI-C is an FBI using coal as auxiliary fuel. Thestant flow rate of 1.2 ml/min. The mass spectrometer relatively high sulfur in the coal can inhibit th(MS) was operated at a resolution of 10000 under PCDD/Fs formation, which has been confirmed bypositive electron ionization (EI) condition (38 eV many studies (Gullett et al., 1992; 1998; 2000). Oneelectron energy). One ul of sample was injected using of the emission levels of MSWI-D, which is also anan auto-sampler in splitless mode. The PCDD/Fs FBI using MSW and coal as fuel, was 0.162 ngwere quantified using a molecular ion (M), an M+2 I-TEQ/Nm'. The relatively high emission level mayion or an M+4 ion. The I-TEQs was calculated using be due to the poor APCD, which is composed of cy-the international toxic equivalence factor (I-TEF) clone and wet scrubber. Takaoka et al.(2003) inves-(NATO/ CCMS, 1988).tigated the behavior of PCDD/Fs in WS system of twoMSWIs, and reported that PCDD/Fs concentration inthe flue gas at outlet of WS was higher than that atRESULTS AND DISCUSSIONinlet of WS in both MSWIs.PCDD/Fs concentration in the flue gasProfiles of homologue and congener of PCDD/FsPCDD/Fs concentration in the flue gas was in the flue gasshown in Table 2. The I-TEQ values were in the rangeProfiles of PCDD/Fs homologue in the flue gasof 0.019~0.201 ng I-TEQ/Nm', which were all lower from MSWI-A to MSWI-D were shown in Fig.2. Forthan the standard limit of China (1.0 ng I-TEQNm'). FBIs (MSWI-C and MSWI-D), the PCDFs levelsIn 2001, the State Environmental Protection Admini- were all greater than those of PCDDs and the lowerstration (SEPA) of China investigated the pollutants chlorinated furans were dominant for PCDFs, whichincluding PCDD/Fs emission from 15 MSWIs. The was similar to the emission characteristic of PCDD/Fsinvestigated results showed half data of PCDD/Fs from Chinese and Korean MSWIs (Oh et al., 1999;concentration in the flue gas exceed 1.0 ng Yan et al, 2006). However, for the grate fired incin-I-TEQ/Nm', indicating that the emission levels of erators (MSWI-A and MSWI-B), the PCDDs levelsPCDD/Fs from the MSWIs have been reduced over were slightly greater than those of PCDFs for onethe past few years. However, half data of the emission sampling, and the ratios of PCDDs and PCDFs areresults were slightly higher than the developed coun- 1.15 and 1.03, respectively, but for another sampling,tries emission limit of 0.1 ng I-TEQ/Nm'. So the similar ratios of PCDDs and PCDFs were observed ascontrol technologies for PCDD/Fs need to be im-those of FBIs. The difference of the homologue pro-proved if the emission limit was lowered to 0.1 ng files in the flue gas from FBIs and grate fired incin-I-TEQ/Nm'.erators may中国煤化工prevailingYHCNMH G.Chen et al. / J Zhejiang Univ SciA 2008 9():1296-130312992.8First sampling2.4-Second samplinga)(b)2.0F1.51.6F1.2I 1.0; 0.80.4-(c)(d)营2.4-f2.0F; 0.0.1昌0.4?oPCDD/Fs homologueFig.2 Profiles of PCDD/Fs homologue in the flue gas from (a) MSWI-A, (b) MSWI-B, (c) MSWI-C and (d) MSWI-Dmechanisms of PCDD/Fs formation.ated dibenzo-p-dioxin (PeCDD) were two majorAlthough the profiles of PCDD/Fs homologue in 2,3,7,8-substituted congeners, and their contributionsthe flue gas from FBIs and grate fired incinerators were up to 47% and 9% (average values) of the totalwere different, the 2,3,7,8-substituted congeners dis- TEQ values, respectively, due to their high toxicitytribution patterns were similar for all MSWIs (Fig.3). (I-TEF value is all 0.5). Kato and Urano (2001) alsoThe comparison between this data and others ob- found that 2,3,4,7,8-PeCDF and 1 ,2,3,7,8-PeCDDtained from Harbin of China, Korea and Japan was contributed to about 49% of the ITEQ values. Theshown in Fig.4. The very similar distribution of contribution of 2,3,4,7,8-PeCDF was stable, though2,3,7,8-substituted congeners was found in Chinese the contribution of 1,2,3,7,8-PeCDD fluctuated.MSWI. For example, 1,2,3,4,6,7,8-hepta-chlorinated Several researchers have reported a linear correlationdibenzo-p-dioxin (HpCDD) and octa-chlorinated between the 2,3,4,7,8-PeCDF concentration and TEQdibenzo-p- dioxin (OCDD) were the major congeners values (Fiedler et al, 2000; Kato and Urano, 2001;for PCDDs.2,3,4,7,8-penta-chlorinated dibenzofuran lino et al., 2003). The positive correlation was ob-(PeCDF) and 1,2,3,4,6,7,8-hepta-chlorinated diben- tained from this paper (Fig.5), which was differentzofuran (HpCDF) were the predominant congeners from the results of Kato and Urano (2001). In theirfor PCDFs. However, there was different distribution study, the correlation between the 2,3,4,7,8-PeCDFfor PCDD/Fs emission from MSWI in Korea and concentration and I-TEQ values could be describedJapan. 2,3,4,6,7,8-hexa-chlorinated dibenzofuran by the following Eq.(1). The difference coefficient(HxCDF) and 1,2,3,4,6,7,8-HpCDF amounted to maybe attributed to different MSW composition,more than 54% of total PCDFs for MSWI in Korea. furnace type, etc. In this study, the correlation could1,2,3,4,6,7,8-HpCDF and octa-chlorinated dibenzo- be described by Eq.(2).furan (OCDF) were the major congeners for PCDFsof MSWI in Japan.[I-TEQ of PCDD/Fs]=1.4[2,3,4,7,8-PeCDF]，(1)2,3,4,7,8-PeCDF and 1,2,3,7,8- penta-chlorin-[I-TEQ of PCDD/Fs]=2.1[2,3,4,7,8-PeCDF]. (2)中国煤化工MHCNMH G.1300Chen et al. / J Zhejiang Univ SciA 2008 9():1296-13030.10F一First sampling0.05First samplingSecond sampling(aI Second sampling(b)0.08 t0.04 t0.0603-0.0402 t0012(c)(d! Second sampling0.010 ".05 t0.008.04 f0.00603 F0.00402 [01 Fr山.... ..m... 」o_on_aoPCDD/Fs congenersFig.3 Profiles of PCDD/Fs congeners in the flue gas from (a) MSWI-A, (b) MSWI-B, (c) MSWI-C and (d) MSWI-DCorrelation PCDD/Fs levels with the composition between CO values and the PCDD/Fs levels inof flue gasMSWIs or pilot incinerators (Weber and Hagenmaier,It is well known that various factors can affect 1999; Weber et al, 2002). In the present study, COPCDD/Fs emission. Composition of flue gas is one of values showed no positive correlation with PCDD/Fsthe factors. Table 3 shows the composition of flue gas levels. In MSWI-A, the CO values were lower thanand the PCDD/Fs levels in MSWI-A and MSWI-C. the detect limit of the flue gas analyzer. The case wasCO, O2, water and other compounds were continu- on the contrary for MSWI-C. But the PCDD/Fs levelsously measured for about 30 min by using a flue gas in the MSWI-A were higher than those of MSWI-C.analyzer during the PCDD/Fs sampling process. Al-O2 content also affected the PCDD/Fs formation.though there are only 4 datasets available in Table 3，Chang and Huang (2000) investigated the effect of O2the similar results were found.content on the PCDD/Fs formation in MSW fly ash.CO value, one of the parameters to judge the They found that the PCDD/Fs formation increasedcombustion quality, has been used as a parameter to with the increase of O2 content in electrostatic pre-evaluate PCDD/Fs emissions in several studies. Sa- cipitator (ESP) fly ash. We also found a positive cor-kurai et al.(2000) found that new FBIs with well relation between PCDD/Fs levels (TEQ value) and O2controlled combustion emitted less PCDD/Fs in flue content as shown in Table 3. In China, the PCDD/Fsgas and fly ash, while old FBIs with high CO con-emission standard for MSWIs was based on standardcentration had higher PCDD/Fs emission. However, dry gas correcte中国煤化工O2 contentother studies indicated no significant correlation was higher thanvels wouldfYHCNM H G'.Chen et al. / J Zhejiang Univ SciA 2008 9():1296-13031301be higher than the detected value. It was reported that gas flow (Addink and Olie, 1995). Stieglitz et al.(1990)PCDD/Fs emission was minimal when the O2 content reported that PCDD/Fs formation levels from carwas between 6%~ 9% (v/v) (Yan et al, 2006). So O2 bon/fly ash at 300。C with water increased comparedcontent might be a parameter for PCDD/Fs control- to those without water. However, Jay and Stieglitzling.(1991) found a decrease of the total PCDD/Fs amountsAs MSWI flue gas contains water, experiments formed in the presence of water with charcoal/were performed in several studies to compare the MgSiO2/CuCl2 in air at 300。C. Li et al.(2006) inves-formation of PCDD/Fs with and without water in the tigated the effect of water vapor on catalyzed de novoformation of PCDD/Fs. Their results indicated thatThis data (mean value)water vapor could promote the PCDD/Fs formation.写2.TakaealL200'1We also found a positive correlation between waterE 2.0and TEQ values of PCDD/Fs as shown in Table 3.E 1.sIt has been reported that co-firing coal withMSW could reduce PCDD/Fs emissions due to theincreased flue gas SO2 concentration (Ryan et al.,告0.2006). Introducing SO2 into the furmace section of afull-scale incinerator (SO2 concentrations from 20 to2000 mg/m') resulted in a decline of PCDD/Fs con-centration in flue gas (Ruokojarvi et al, 2004). Theconversion of metal chloride in the fly ash to sulfates1893了may be the main mechanism of PCDD/Fs suppressing,PCDD/Fs congenerswhich had been confirmed in the pilot plantFig.4 Comparison between this data and other dataTAMARA (Hunsinger et al, 2006). The chloridefrom the literatureconcentrations in the fly ash decreased significantlyfrom ~200 mg/g down to below the detection limit ofabout <3 mg/g. Table 3 showed the S/Cl mole ratios0.25in flue gas from MSWI-A were both about 0.2,y=2.1271xhowever, those in flue gas from MSWI-C were 9.30.20”R2=0.9748and 6.9, respectively. The increased S/CI mole ratio ini 0.15flue gas would lead the decrease of PCDD/Fs, whichcould be calculated from the data of Table 3.0.100.05CONCLUSION0 0.02 0.04 0.06 0.08 0.10 0.12The flue gas from two grate-type MSWIs and2,3,4,7,8-PeCDF concentration (ng/Nm3)two fluidized bed MSWIs were analyzed forFig.5 Relationship between 2,3,4,7,8-PeCDF concentra-PCDD/Fs. The total concentration and TEQ values oftion and TEQ values in MSWI-A to MSWI-DPCDD/Fs emission were in the range of 1.210- ~Table 3 Composition of flue gas and the PCDD/Fs levels (standard dry gas at 11% (v/v) 02)CompositionPCDD/Fs levelsIncinerator COWaterNOx_SO2.HCIPCDD/Fs(mgNm)__ (%。 v/v)(%, v/v)__ (mgNm)__ (mgNm)__ (mgNm)__ (ngNm)__ (ng I-TEQ/Nm)MSWI-A<112.818.2119.553. l185.00.200<11.516.8129.570.0179.79.40.170757.46.10.6 .99.4220.513.5.60.026 .MSWI-C1102.796.2256.4| 中国煤化工019Note: The values except PCDD/Fs levels were the average values during 30 min samplingfYHCNMH G.1302Chen et al. / J Zhejiang Univ SciA 2008 9():1296-130310.273 ng/Nm', 0.019~0.201 I-TEQ ngNm', respec-combustion. Environmental Science & Technology, 34(2):tively, which were all greatly lower than the standard282-290. [doi: 10.1021/es990605z]of the PCDD/Fs emission regulation (1.0 ngHunsinger, H，Seifert, H，Jay, K., 2006. Reduction ofI-TEQ/Nm') in China, however, only the PCDD/FsSO2 Cycle. Intermational Conference on Incineration &emission levels from MSWI-C below 0.1 ngThermal Treatment Technologies, Savannah, Geogia,I-TEQ/Nm'.USA. .Although the profiles of PCDD/Fs homologue in lino, F, Takasuga, T, Touati, A., Gulltt, B.K, 2003. Correla-the flue gas from different type MSWIs were different,tions between homologue concentration of PCDD/Fs andtoxic equivalency values in laboratory-, package boiler-,the 2,3,7,8-substituted congeners distribution patternsand field-scale incinerators. Waste Management, 23(8):were similar for all MSWIs. Two major 2,3,7,8-sub-729-736. [doi:10.1016/S0956-053(02)00146-0]stituted congeners were 2.3.4.7,8-PeCDF and Jay, K Sigliz, L, 1991. On the mechanism of formation of1,2,3,7,8-PeCDD. The positive relationship betweenpolychlorinated aromatic compounds with copper (I)the 2,3,4,7,8-PeCDF concentration and TEQ values .chloride. Chemosphere, 22(11):987-996. [doi:10.1016/0045-6535(91)90299-S]could be described by the following equation: [I-TEQKato, M, Urano, K., 2001. Convenient substitute indices to .of PCDD/Fs]=2.1[2,3,4,7,8-PeCDF].toxic equivalent quantity for controlling and monitoringIt was observed that a correlation exists betweendioxins in stack gas from waste incineration facilities.PCDD/Fs emission and the contents of O2, water,Waste Management, 21(1):55-62. [doi:10.1016/S0956-S/CI mole ratio, but not CO in flue gas, so these pa-053000048-9]rameters could be adjusted for PCDD/Fs emissionKim, s.c, Jeon, S.H, Jung, 1.R., Kim, K.H, Kwon, M.H,Kim, J.H, Yi, J.H, Kim, S.J,, You, J.C, Jung, D.H, 2001.controlling in MSWIs.Formation and emission status of PCDDs/PCDFs in mu-nicipal solid waste incinerators in Korea. Chemosphere,References43(4-7):701-707. [doi:10.1016/S0045-653500)00423-9]Addink, R., Olie, K, 1995. Mechanisms of formation and Li, M., Xiang, J, Hu, s. Sun, L.S, Su, s., Li, P.S., Sun, x.X,destruction of polychlorinated dibenzo-p-dioxins and2004. Characterization of solid residues from municipaldibenzofurans in heterogeneous systems. Environmentalsolid waste incinerator. Fuel, 83(10):1397-1405. [doi:10.Science & Technology, 29(6): 1425-1435. [doi:10.1021/1016/j.fuel.2004.01.005]es00006a002]Li, X.D., Zhang, J, Yan, J.H, Chen, T, Lu, S.Y, Cen, K.F,Bie, R.S, Li, S.Y,， Wang, H, 2007. Characterization of2006. Effect of water on catalyzed de novo formation ofPCDD/Fs and heavy metals from MS W incineration plantpolychlorinated dibenzo-p-dioxins and polychlorinatedin Harbin. Waste Management, 27(12): 1860- 1869.dibenzofurans. Journal of Hazardous Materials, 137(1):[doi:10. 1016/jwasman.2006.10.014]57-61. (doi:10.1016/j.jhazmat.2006.01.068]Chang, M.B., Huang, TF, 2000. The effects of temperature NATO/CCMS, 1988. International Toxicity Equivalence Fac-and oxygen content on the PCDD/PCDFs formation intor (I-TEF) Method of Risk Assessment for ComplexMSW fly ash. Chemosphere, 40(2):159-164. [doi:10.Mixtures of Dioxins and Related Compounds. Report No.1016/S0045-65359900227-1]176, August 1988, NATO, Comittee on Challenges ofFiedler, H, Lau, C., Eduljee, G, 2000. Statistical analysis ofModern Society.pattems of PCDDs and PCDFs in stack emission samples Oh, JE., Lee, K.T, Lee, J.W., Chang, Y.S, 1999. The evalua-and identification of a maker congener. Waste Manage-tion of PCDD/Fs from various Korean incinerators.ment and Research, 18(3):283-292. [doi:10. 1034/j.1399-Chemosphere, 38(9):2097-2108. [doi:10.1016/S0045-3070. 2000.00109.x]6535(98)00419-6]Gulle, B.K., Bruce, K.R, Beach, L.O, 1992. Efct of sulfur Ruokojarvi, PH, Asikainen, A.H， Tuppurainen, K.A.,dioxide on the formation mechanism of polychlorinatedRuuskanen, J, 2004. Chemical inhibition of PCDD/Fdibenzodioxin and dibenzofuran in municipal wasteformation in incineration processes. Science of the Totalcombustors. Environmental Science & Technology, 26:Environment, 325( l -3):83-94. [doi: 10.1016/j.scitotenv.1938- 1943.2003.11.006]Gullett, B.K., Raghunathan, K., James, E.D., 1998. The effect Ryan, S.P, Li, X.., ulelt, B.K., Lee, C.w., Clayton, M.,of co-firing high sulfur coal with municipal waste onTouati, A., 2006. Experimental study on the effect of SO2formation of polychlorinated dibenzo-p-dioxins andon PCDD/F emissions: determination of the importancedibenzofurans. Environmental Engineering Science,of gas-phase versus solid-phase reactions in PCDD/F15(1):59-70.formation. Environmental Science & Technology, 40(22):Gullett, B.K, Dun, JE., Raghunathan, K, 2000. Efect of7040-7047. [doi:10.1021/es0615369]cofiring coal on formation of polychlorinated Sakurai, T, Webe中国煤化工 Suki A..dibenzo-p- dioxins and dibenzofurans during waste2000. Dioxinzed bed solidTYHCNMHG.Chen et al. / J Zhejiang Univ SciA 2008 9():1296-13031303waste incinerator. Organohalogen Compounds, 45:356- US EPA (Environmental Protection Agency) Method 1613B,59.1994. Tetra-through Octa-chlorinated Dioxins and FuransStieglitz, L, Zwick, G, Beck, J, Bautz, H, Roth, W, 1990.by Isotope Dilution HRGC/HRMS. Washington, DC.The role of particulate carbon in the de- novo synthesis of Weber, R., Hagenmaier, H, 1999. PCDD/PCDF formation inpolychlorinated dibenzodioxins and-furans in fly-ash.fluidized bed incineration. Chemosphere, 38(11):2643-Chemosphere, 20( 10- 12):1953- 1958. [doi:10. 1016/0045-2654. [doi:10. 1016/S0045-6535(98)00472-X]6535(90)90365-Z]Weber, R., Sakurai, T, Ueno, S., Nishino, J, 2002. CorrelationTakaoka, M, Liao, P, Takeda, N, Fujiwara, T, Oshita, K,of PCDD/PCDF and CO values in a MSW incinerator-2003. The behavior of PCDD/Fs, PCBs, chlorobenzenesindication of memory efects in the high tempera-and chlorophenols in wet scrubbing system of municipal .ture/cooling section.Chemosphere，49(2):127-134.solid waste incinerator. Chemosphere, 53(2):153-161.[doi:10. 1016/S0045-6535(02)00187-X][doi:10.1016/S0045- 6535(03)00437-5]Yan, J.H, Chen, T, Li X.D., Zhang J, Lu S.Y., Ni, MJ, Cen,Tian, H.H, Ouyang, N, 2003. Preliminary investigation onK.F, 2006. Evaluation of PCDD/Fs emission from flu-dioxins emission from MSW incinerators sources. Enviidized bed incinerators co-firing MSW with coal in China.ronmental Chemistry, 22:255-258 (in Chinese).Journal of Hazardous Materials, 135(1-3):47-51. [doi:10.uS EPA (Environmental Protection Agency) Method 0023A,1016/jhazmat.2005.12.007]1996. Sampling Method for Polychlorinated Dibenzo- Zhu, JX, Hirai, Y., Sakai, S, 2005. Sources and Emissions ofp-dioxins and Polychlorinated Dibenzofuran EmissionsPCDD/PCDFs in China. Organohalogen Compouds,from Stationary Sources.p.1062- 1065.中国煤化工MYHCNMH G.