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1 w y wz 9«( 2y) 84~90, 2006 J. of the Korean Society for Environmental Analysis ys» ƒ y Áz XRF XRD p ½ «Á«Á Á *Á y w, *swœ w Analytical Characteristics of XRF and XRD Before and After Stabilizing the Fly Ash from MSW Incineration Plant Kim Sam-Cwan, Kwon Myung-Hee, Jeon Jong-Ju, Song Geum-Ju, and Song Sun-Hee National Institute of Environmental Research (NIER), Environment Research Complex, Seogu Kyungseo-dong, Incheon, Korea *Pohang University of Science and Technology (POSTECH), Nam-gu Hyoja-dong, Pohang-si, Kyungsangbukdo, Korea Ministry of Environment has regulated fly ash from municipal solid waste (MSW) incineration plant as a designated waste by Waste Management Act because of its hazardous components such as heavy metals and dioxins. By this reason, fly ash has been stabilized using either metallic or chemical agents prior to final land disposal. In this study, fly ash was stabilized using chemical agents and portland cement in order to know the compositional and characteristic variation of heavy metals in fly ash before and after stabilization. Raw and stabilized fly ashes were analyzed by X-ray fluorescence spectrometer (XRF), X-ray diffractometer (XRD). The results were summarized as follows. Mass spectrometer's result showed that the major components in stabilizing agents was methyl N-dimethyl thiocarbamate (C 4 H 49 ONS), dimethyl carbamodithioic acid (C 3 H 6 NS 2 ) and tetramethyl thiourea (C 5 H 12 N 2 S). Also, XRD's result showed that raw fly ash largely contained CaClOH, Ca(OH) 2 and CaC, which were considered to be resulted from the spray of lime for controlling acidic pollutants at spray dryer absorber (SDA). When adding 2% to 5% (w/w) of chemical agents into fly ashes there were almost no compositional variations of heavy-metal components in stabilized fly ashes, but the compositional percentiles of Na 2 O and SiO 2 were somewhat decreasing while that of CaO was slightly increasing. When adding 5% of chemical agents and 10% to 30% (w/w) of portland cement into fly ashes, the compositional percentiles of SiO 2, Al 2, CaO and S were considerably increased while those of Na 2 O, Cl, K 2 O were relatively decreased. Accordingly, the basicity (CaO/SiO 2 ) of stabilized fly ashes were decreased to a level of 7.53±12.57 from of raw fly ash. Key words : Fly Ash, MSW, Incineration Plant, XRF, XRD, Stabilizing Agent 1. s» ƒ, ƒ s» ƒ jš ù z ƒ y (grate) l (bottom ash), ƒ ƒ wì (carryover) w ƒ z s þƒ» Á (fly ash) w x, ü 33 s» ƒ ƒ 420 m, m w z 5 2 wš 1). p, ys» ƒ z y, ƒ ƒ x ys» ƒ ƒw ƒ š, w x œ ƒ w ù œ ƒ x ys» ƒ 7 2) w» ƒ ƒ ƒ To whom correspondence should be addressed. kscnier@me.go.kr

2 ys» ƒ y Áz XRF XRD p 85 ƒ (Table 1). ù, ƒ Pb, Cu, Cr, Hg w w» w 3), w w e 2 y j» z w v w. w xw s» 4) ƒ 1) x w ù, 2) y w ù, 3) páw š yw w šxy w ³ wš., xw s» s» w š, x ù š y x š. wr, y f, w w w ƒ y, y w k p (chelating agent) w w w ƒ û yy xk y g e y j (PbO, HgO + S PbS, HgS)., k pyw y w w y, x k pyw w w ƒ û e 5,6)., y Nitrilotriacetate (NTA), Ethylendiamine tetra-acetate (EDTA), Diethylene triamine pentaacetate (DTPA) Amino-polyacetate w w ƒ jù, Thiol (-SH) Dithiocarbamate (-NH-CSSH) k p w w w yw y y z ùküš š 7). ù ys» x ƒ s, k-», ü q y sp p yww y wš, y w y p yw w w, y Áz y p X- xÿ» X- z» w r. 2. x 2.1. ƒ y x w Fig. 1 ys» ƒ ( ƒ : 200m/, 2») w. ƒ s (Waste Heat Boiler, WHB), y y (SOx) y (HCl) ƒ w» w z (lime) w k (Spray Dryer Absorber, SDA), w» w» (Bag Filter, BF), y (NOx) w» w k y e (Selective Catalytic Reduction, SCR). s SDA-BF wœ w (Fly-ash silo) w. x w z s p s x w, œ» yk w w8) š w w w. Table 1. Generation amounts of incineration residues from commercial-scale MSW incineration plants (unit : ton/year) Incineration Plant* Incineration Residues 210, , , , , ,456 - Bottom Ash 185, , , , , Fly Ash 25,164 37,372 61,765 61,642 64,713 67,759 *1 : Number of Incineration plant with a treatment capacity of 2 ton/hr or more Fig. 1. Process of incineration facility and sampling point of fly ash.

3 86 ½ «Á«Á Á Á 2.2. y x x ü q š 3ƒ y (E, H, N t), y w y g, y sp p p (Portland cement) yww y g Ásƒ w. y x w : : = 100 : 30 : x» 2%, 3%, 5% y g x w, y p yw x w : : : p = 100 : 30 : 5 : x p 10%, 20%, 30% y( y 5% š ) g y w y y w (acetone) w z, y (1 µl) ƒ j m v/ (Gas Chromatograph/Mass Spectrometer, GC/MS) (GC Model: Autosystem GC XL, Perkin Elmer Ltd., Mass Model: Turbo Mass Spectrometer, Perkin Elmer Ltd.) w y Áz y y Áz y q w» w X- xÿ» (X-Ray Fluorescence Spectrometer, XRF, Model: Shimatzu XRF-1700) ü UniQuant w w, w y q w» w X- z»(x-ray Diffractometer, XRD, Model: Philips X'pert-MPD System) w w. XRD ç(Cu) q, 2 theta 5~75 o (Scanning) w Monochromator q w. 3. š 3.1. y ü q y t ƒ j š. rp w, Methyl N-Dimethyl Thiocarbamate (C 4 H 49 ONS), Dimethyl carbamodithioic acid (C 3 H 6 NS 2 ), Tetramethyl thiourea (C 5 H 12 N 2 S) ùkû 5,6). 3ƒ t œm Thiocarbamate, t N H t E w Thiourea Dithiocarbamateƒ w. yw y w Carboxylic Thiol, Carbamate 9,10) w ùkû, p Thiourea Sodium sulfide w y 11) y XRF y y XRF w Table 2 ùkü. r, y Áz y ù, Na 2 O SiO 2 y z w w ù kü CaO y z ƒw w ùkü., y z (basicity)ƒ (raw) ~23.37 ƒw ùkü. SiO 2 w w CaO w» (CaO/ SiO 2 ) w,» ƒ 16.35» 1 w12,13). ƒ (, )» ƒ ƒ phƒ š, ƒ w Pb, Zn ƒ, w» ƒ ƒ w v w 8). wr, š w y Áz y, y w ƒ m ƒ»yw m ƒ ƒ, yƒ š xk ë», ƒ xk y ƒ w w ƒ w sƒw XRF w yƒ ùkù q y p yw y 5% p wì yw w y w, Table 3 Na 2 O, Cl, K 2 O w

4 ys» ƒ y Áz XRF XRD p 87 Table 2. XRF analysis results of fly ash, stabilized by chemical agents (unit : dried weight %) Items Raw fly ash E Product H Product N Product 2% 3% 5% 2% 3% 5% 2% 3% 5% Na 2 O Mg Al SiO P S Cl K 2 O CaO TiO Cr Fe CuO ZnO PbO Br MnO SrO CdO BaO SnO SUM Basicity # Basicity # Basicity # Basicity #1: CaO/SiO 2, Basicity #2: CaO/(SiO 2 + Al 2 ). Basicity #3: CaO/(SiO 2 + P 2 ) ù, SiO 2, Al 2, CaO, S ƒw ùkû. sp p p SiO 2 CaO w p 87% w, Al 2, Fe 2, S» q 14). p, SiO % p ƒ 10% 4.10~5.03% p ƒ 30% 6.38~7.16% ƒw š, CaO 48.88% p ƒ 10% 51.53~ 54.83% p ƒ 30% 53.88~ 56.19% ƒw., p ƒ SiO 2 CaO ƒw ùkû, SiO 2 ƒs CaO j» y z» y ƒw ~12.57 w p ƒ w ùkü y XRD y XRD w z XRD w Fig. 2~5 ùkü. Fig. 2 w XRD r, CaClOH, Ca(OH) 2, CaC e sw š. ƒ» k(spray Dyer Absorber, SDA) z w q. y 5% yww w XRD r, w y NaCl, KCl, KAlCl 2 O, CaClOH y ùkû. ù ƒ z w Ca(OH) 2 CaC, 3 ƒw

5 88 ½ «Á«Á Á Á Table 3. XRF analysis results of fly ash, stabilized by chemical agents with portland cement (unit : dried weight %) Items Raw fly ash Cement (adding with E product of 5%) Cement (adding with H product of 5%) Cement (adding with N product of 5%) 10% 20% 30% 10% 20% 30% 10% 20% 30% Na 2 O Mg Al SiO P S Cl K 2 O CaO TiO Cr Fe CuO ZnO PbO Br MnO SrO CdO BaO SnO SUM Basicity # Basicity # Basicity # Basicity #1: CaO/SiO 2, Basicity #2: CaO/(SiO 2 + Al 2 ). Basicity #3: CaO/(SiO 2 + P 2 ) Fig. 2. XRD analysis result of raw fly ash. ùkûš, p Fig. 4 H t 5% ƒw CaSO 4 ƒ 2 ƒw ùkû. l,» w ƒ Ca(OH) 2 CaC SO 4-2 w CaSO 4 15)w. Fig. 3. XRD analysis result when adding 5% of stabilizing agent E to raw fly ash p yw y p yw w z XRD w Fig. 6~8 ùkü. p yw w, š(caso 4Á2H 2 O), CaSO 4 NaCl KCl

6 ys» ƒ y Áz XRF XRD p 89 Fig. 4. XRD analysis result when adding 5% of stabilizing agent H to raw fly ash. Fig. 7. XRD analysis results when adding 5% of stabilizing agent H with 30% of cement to raw fly ash. Fig. 5. XRD analysis result when adding 5% of stabilizing a agent N to raw fly ash. Fig. 8. XRD analysis results when adding 5% of stabilizing agent N with 30% of cement to raw fly ash. Fig. 6. XRD analysis results when adding 5% of stabilizing agent E with 30% of cement to raw fly ash. w 2 ƒw. šƒ p CaOÁSiO 2, CaOÁAl 2 y y wš, wì yw y CaSO 4Á2H 2 Oƒ». 4. ù x ys» ƒ ü q y sp p yww y wš, y Áz y p X- xÿ» X- z» w r. 1. ü q y Methyl N-Dimethyl Thiocarbamate (C 4 H 49 ONS), Dimethyl carbamodithioic acid (C 3 H 6 NS 2 ), Tetramethyl thiourea (C 5 H 12 N 2 S) ùkûš, t ƒ j š ùkû. 2. XRD w, CaClOH, Ca(OH) 2, CaC e sw š ùkûš, ƒ» k z w q. 3. y ƒw y Á z y XRF w, y ù Na 2 O SiO 2 y z w w ùkü, CaO y z ƒw w ùkü. w, y Á z y XRD w, w y NaCl, KCl, KAlCl 2 O, CaClOH y ù kû ù, ƒ z w

7 90 ½ «Á«Á Á Á Ca(OH) 2 CaC 3 ƒw ùkû. Ca(OH) 2 CaCƒ SO 4-2 w CaSO 4 w q. 4. y 5% p wì yw w y w, Na 2 O, Cl, K 2 O w ù SiO 2, Al 2, CaO, S ƒw ùkû. w, SiO 2 ƒs CaO j», y z» ~12.57 w p ƒ» ƒ w ùkü. w, XRD, CaSO 4Á2H 2 O, CaSO 4 NaCl KCl w 2 ƒw ùk û. CaSO 4Á2H 2 O p CaOÁSiO 2, CaOÁAl 2 y y wš, wì yw CaSO 4Á2H 2 Oƒ». š x 1. y, 2001~2006, 2000 ~2005 x ys» ƒ xy. 2. y, 2005, œ ƒ xy. 3. Karl Joachim Thome-Kozmiensky, K.J., 1994, Thermische Abfallbehandlung, EF- Verl.fuer Energieund Umwelt-technik, y, 2004, s». 5. ½ «,», ¼, «,, y y,,,,, 2001, s» ƒ ƒ w (II)- -, y, NIER No ½ «, «,,,, y w ƒ y z»e p w, w s» wz, 2005, Vol. 22 No. 6, Kyung-Jin Hong, Shuzo Tokunaga, Toshio Kajiuchi, Extraction of heavy metals from MSW incinerator fly ashes by chelating agents, Journal of Hazardous Materials, 2000, B75, ½ «,», ¼, «,,,,,, ½»x, 2000, s» ƒ ƒ w (I)- -, y, NIER No , M.M. Matlock K.R. Henke, D.A. Atwood, Effectiveness of commercial reagents for heavy metal removal from water with new insights for future chelate designs, Journal of Hazardous Materials, 2002, B92, Wu-Jang Huang, Hji-Shih Lo, Synthesis and efficiency of a new chemical fixation agent for stabilizing MSWI fly ash, Journal of Hazardous Materials, 2004, B112, Zhao Youcai, Song Lijie, Liguojian, Chemical stabilization of MSW incinerator fly ashes, Journal of Hazardous Materials, 2002, B95, ~ «, l l«, Œª, 1994, Vol. 5, No. 1, hhn š, 1997, q-syrkno ~ l kkgk,, 27, œœ, 1988, Œ ŠÁxs qrxl k, ˆž, Shao-Hua Hu, Stabilization of heavy metals in municipal solid waste incineration ash using mixed ferrous/ferric sulfate solution, Journal of Hazardous Materials, 2005, B123,