16(4)-05.fm

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1 w m y Vol. 16(4), p. 53~61, 2011 œ 광물찌꺼기에함유된오염물질의안정화를위한표면차폐재의성능평가 ½ ³ 1 Á 1 *Á½ 2 Á½ 2 Á 3 Á 3 1 w œ w œw, 2 ( ) f lp, 3 w Ÿw œ Ÿw» Evaluation of Surface Water-preventing Materials on Stabilization of Contaminants in Tailings Young Kyu Kim 1 ÁMyung Chae Jung 1 *ÁJung Yul Kim 2 ÁYoo Sung Kim 2 Jin-Soo Lee 3 ÁKwan In Park 3 1 Department of Energy and Mineral Resources Engineering, Sejong University 2 Soam Consultant 3 Institute of Mine Reclamation Technology, Mine Reclamation Corporation ABSTRACT This study examined evaluation on stabilization of major and trace elements in tailings by various surface waterpreventing materials. Six columns were filled with tailings of the Sinlim mine, then covered with tailings only, compacted soils, clay, soil-bentonite mixture, pozzolan and bentonite mat. After injection of artificial rain water, the leachate was sampled with times (3, 6, 9 and 12 pore volume) and analysed for major (Ca, Na, Mg, K) and trace elements (As, Cd, Cu, Pb, Zn) by ICP-AES. With exception to pozzolan type, the ph values of leachate from the other types became stabilized from 5.5 to 7.5, and EC (electric conductivity) of leachate from them decreased with times. For the pozzolan type, however, the ph and EC of leachate increased with time due to its alkalinity producing system. Concentrations of most major and trace elements in leachate decreased and stabilized with time. Consequently, soil-bentonite mixed cover shows the best ability of water-preventing and reducing mobility of elements in tailings site. Key words : Column test, Heavy metals, Surface water-preventing materials, Stabilization, Tailings 1. {ÁsŸ e Ÿ É»ù s Ÿ s» w w w wš, w e, w m, w» w xk Ÿw k (Jung and Thornton, 1996;, 2004). y (w Ÿw œ ) s Ÿ y ww w ( Á, 2006) w, Ÿ ƒ¾ y» w, w. w Ÿw œ ƒw Ÿ w Ÿw wš, w Ÿw œ š Ÿ s» s y w Á, šxyá y, m, y,» y, w ( w, 2005; Kim et al., 2005; x xá½ ¼, 2007;, 2008; Kim and Jung, 2011).» Ÿ s» m, w, t l Á j œ w œ w ƒ w š. w» Ÿ É» *Corresponding author : jmc65@sejong.ac.kr š : : : m : ¾ 53

2 54 ½ ³Á Á½ Á½ Á Á e mw w z û r (, 2002; Á, 2006). w wš z w» mw l w ƒ w ( ¼, 2008),» w ƒ ƒ w š. w y y w yœ p s w Ÿ É» šy g y yw šxyœ š (Jang and Kim, 2000; w, 2005; Choi et al., 2009; Kim and Jung, 2011). ü šxy/ y» y w š (Dutre and Vandecasteele 1998; Bothe and Brown, 1999; Bose and Sharma 2002; Jakubick et al. 2003; Singh and Pant, 2006). p Singh and Pant(2006) sp p p,, s šxy w. w x ³ Ÿ É» m šx y y mw, x y w», z œ w ƒ. p x Ÿ É» sww Ÿ s» p w w w sww š y w Ca, Na, Mg, K sww p w w r. x ü Ÿ É» e w sœ y wš ws» w œ wš, Ÿ k w e w ww ù Ÿ É» sœ w» s» t sœ w w sœ w x ww Ÿ É» e ww sœ w wš. Ÿ É» e z s w» w s» m, m - mù pywm, s ( z + Ÿ É»), mù p p s w s z mwš œ ( ) w sd w e y y w yw s w wš w Ÿ xy w Ÿ Ÿ É» s y w y x ww y( 96y) Ÿ, t '35'', 37 14'42'' ew. z {Ÿ k ƒ 1987 l ˆ l w3ˆ¾ w 1 30m ³ Ÿ ƒ w 2004 Ÿ «. Ÿ e» r, y r š z, r Ÿ,,, w swš. š ³ sw z z³ ( wÿ œ, 1987; ½ x, 1996) x Ÿ É» e s w Ÿ É» x(tailings type), mx(compacted soil type), mx (clay type), s x(pozzolan type), m - mù py wmx(soil-bentonite mixture type), mù p px (bentonite mat type) 6 w., n y w» w d w n d w. w, x š 6ƒ œ x w» w e x ww, ƒƒ ³ Fig. 1 w. Φ8cm 24cm x j e Ÿ É» z, w s š w v 20% ƒ e e ph 5.5~6.0 œ ( ) w. œ n w.» w» w œ ( ) w e w, z» š w œ w z 3 e g e w z œ w. s xk y» w e 3, 6, 9 12 pore volume e

3 Ÿ É» w y w t s sƒ 55 Fig. 1. Schematic diagrams for six columns tested in this study. ph(thermo Orion 250)» (EC, Thermo Orion 115A+) d w. e yw w 60 ml w ƒw z ¾ 4C þ o w, z v Ÿ ŸŸ (ICP-AES) w (Ca, Mg, Na, K) (Cd, Cu, Pb, Zn, As) w s p Ÿ É»» w x Ÿ l ƒe z w Ÿ. Ÿ w w Ÿ w wš. Ÿ É» ü Ÿ É» (, 1999; Á, 2006). Ÿ Ÿ É» x ww, Ÿ É» w w Table 1 w. t m y 2 (,, ) w m y» w,» 500 mg/kg wš,, e, û,» w. Ÿ É» ƒ w. ph 3.3 w w ƒ w ƒ.

4 56 ½ ³Á Á½ Á½ Á Á Table 1. The paste ph and chemical compositions of tailings from the Sinlim mine Mine Paste ph Chemical composition (mg/kg) As Cd Cu Pb Zn Sinlim 3.3 1, ,750 2,570 Table 2. General properties of bentonite used in this study Sample ID Unit LF-12 Form Ca-Activated Moisture % 8.8 Cation exchange capacity meq/100 g 70 Free swell ml/2 g 12 ph value 9.5~10.5 Bulk density about 0.8 (Real density 2.3) Granularity 200 mesh 80% under size (75 µm) x s m w m w. x sƒ w x ³ w wz x š w ƒ w x y w y wš w. m mm w j», s y š. x mƒ sw w š y (cation exchange capacity, CEC) w e ü yw, m s t n cm/s w y w» š s y w» w (x xá½ ¼, 2007). x w m Ÿ y w, mw m m w. mù p k p mÿ Ÿ y, y-q p û n, s» œ, w / w œ,, q w y š (, 1997). x Ÿ w m 20% mù p yww m - mù pywx 100% mù p y w mù p px 2 e x y, mù p yw p Table 2 w., mù p q ƒ r ƒ j x q ƒ m ù p s y w. s z(ca(oh) 2 ) šxy/ y ƒ wš, Ÿ (AMD) y (, 2005). w ù w» y k, z, sp p t, e œ š. y s œ Ÿ É» w e ù z w s g šxyƒ x w s, w z w e f p y (C-S-H gel) ù e p y (C-A-H gel) x w e w» z šxy š (, 2008). (2008) w» Ÿ É» z 11% yww z, w 20% w 28 w s y sƒw. 3. x š 3.1. s n x œ ( ) w ü x x w, û n û w (Fig. 2).,» y» s 2~ cm/s w œ w y sd

5 Ÿ É» w y w t s sƒ 57 Fig. 2. Variation of permeability of various water-preventing materials. Fig. 3. Variation of ph values in effluents from the Sinlim mine tailings treated by various water-preventing materials. 1~ cm/s û. e x ww n ƒ ƒ v 20% w û n z w q e ph y As, Se, Mo y w wš w yy š e y y ƒ w (Bowen, 1979; Alloway, 1995, zk, 1997). œ w z ƒ s l e ph d w Fig. 3 w.» 3 pore volume l 5.5 z ph ƒ ƒw yƒ ph 7.5 z w., py w s ye» w e w ph w y w. 12 pore volume ph 12 ùkù s Fig. 4. Variation of electric conductivity (EC) values in effluents from the Sinlim mine tailings treated by various water-preventing materials. y w. w w ph y» w» ƒ w s w y w ph v w q. 3.3.» y œ w z e» y Fig. 4 w. pore volume ƒw s x w e» ƒ w. ƒ s,» mù p px m - mù p» ùkû m ù p e y yx(ca-activated form) w e sww». w w z w y. s s x»» ƒ ùkû s w ye w» w q. Ÿ É»x û».» y p w w s x y ù ƒ xk., x» û» (2,300 µs/cm) ùkü, û ƒw x 12 pore volume 3,200 µs/cm. w ph w s šy ü ye k w q y 6 s l w œ z

6 58 ½ ³Á Á½ Á½ Á Á Fig. 5. Variation of Ca, Mg, Na and K concentrations in effluents treated by various water-preventing materials. e Fig. 5 w. Ca mù px» w w. w mù pƒ e y yx» ùkù x m mù p 11% yww m - mù pywmx e w x y w. q ƒ š šƒ ùp x mù p ƒ n mw ƒ mù p w y w» x q mù p w, û ƒ yƒ. s ye ƒ ƒƒ ùkù p y w. y ƒ š. mù p w Mg w y š. sx e Mg 12 pore volume 10 mg/l w š. y w z ùkü y w. Na Mg w y š. ƒ m - mù pywm mù p px» Na ƒ 12 pore volume ƒ 10 mg/l z û š. w, s x» û w l Na yƒ ùkû. K Ca w xk., s x wš» K x 12 pore volume 5mg/L z û. w s r j y w ù z ƒ w. w yw q w» Ca œ» w w y 6ƒ l e Fig. 6 w., As 0.04 mg/l w Ÿ É» w 1,340 mg/kg w û š. ƒ l 1~3 10 y 5 z. w mx mx û ƒ š sd y j. w, s x

7 Ÿ É» w y w t s sƒ 59 Fig. 6. Variation of As, Cd, Cu, Pb and Zn concentrations in effluents treated by various waterpreventing materials. As ph w ƒƒ w sƒ. w m - mù x mù p px e ƒ ùkù w sd y sƒ. e 750 mg/kg» 3 pore volume 0.03 mg/l ƒ z w w yƒ y w. p, m ù px» w w ùkù z y w. m y»» w 788 mg/ kg Cu,» s x m - mù px 0.08 mg/l, 0.02 mg/l û. y w Cu yw û ù w û q. Alloway(1995) w» ey Ÿ É»»» w û w w û û q. s x ƒ 12 pore volume 0.25 mg/l» w y» 1mg/L û. û Ÿ É» m y»» w 2,750 mg/kg e 0.02 mg/l w yƒ. Pb Cu w yw w ƒ û e w û Ÿ É» w w û y w z y w. Ÿ É» sww e û y p œ w w w. Zn 2,570 mg/kg e mù px l 6.5 mg/ Lƒ.» mù px s x Ÿ É»x û w 0.5 mg/l w. e yw w ƒ ( zk, 1997), m 0.25%. w

8 60 ½ ³Á Á½ Á½ Á Á y w e û y z y w. ¾ l y z w w n mù px z. p 100% mù p w m ù p px m - mù pywmx z y w. s x r ƒ j y sƒ y šƒ v w q. 4. Ÿ É» x s pilot x 6ƒ sœ ü x³ g e w z œ ( ) w pore volume e yw y, mw. 1) œ w z e ph d w ú phƒ w y y w., s x ye w ph y w wz w w š w. 2) sd ú e» w w ùkþ. l» e x w» ƒ z y mw û xk y w. s x ye w ph» ƒ xk y w. 3) e w w y x x. p, 6 s l Mg Na w y., ye w s x e Ca w ƒ, K w xk. 4) Ÿ É» w w û y e ü y y w., mx mx ƒ ƒ û y z» w û s w yƒ z û q w. 5) 6 s l w w z d m - mù pywmx ƒ w y» q, s x y z. w Ÿw œ Ÿ É» sœ y w,. š x ½ x, z,, 1996, Ÿ - Ÿy, w œwz, 33(4), wÿ œ, 1987, w Ÿ (, r), 10y,, p ¼,,,, ¼, y, «xy, 2008, Ÿ e w, w lœwz, 45(6), ,, ù, 2005, z k e w w y, y, 38(3), , x, x, 2008, Ÿ É» šxy w s œ x sƒ, Ÿw», 2(1), ,, ½, ½, 1999, s Ÿ Ÿ w p, w y œwz 21(1), zk,, 1997, y, w q,, p zk, ½, ½,,, w, 1997, yw, w q,, p. 380., 2002, Ÿ w y xy, 2002 Ÿw» s, w, p ,,, 2004, ü {/sÿ Ÿ y sƒ, y, 37(1), ,, 2006, ü {s Ÿ y sƒ w z, w lœwz, 43(5), w, 2005, Column test mw z šxy/ y ƒ, w w w, p x x, ½ ¼, 2007, s» m» w, wy œwz, 29(1), 3-7. Alloway, B.J., 1995, Heavy Metals in Soils, 2nd ed, Blackie Academic&Professional, London, p Bose, P. and Sharma, A., 2002, Role of iron in controlling spe-

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