Hoi nghi khoa hoc ki thuat md quoc le zuiu Cong nghiep mo tien tien vi su phat triin bin viing K I E M S O A T A X E N T R O N G C A C N H A M A Y C H E B I E N K H O A N G S A N V A C A C L T N G D y[.]
Hoi Cong nghi khoa nghiep mo hoc tien K I E M SOAT A X E N TRONG ki thuat tien md quoc vi su phat le - triin bin zuiu viing CAC N H A M A Y CHE BIEN S A N V A C A C LTNG D y N G T R O N G L A M S A C H C H A T V A O N D I N H C H A T K H O A N G L O N G T H A I Young II NAM, Sang Yun SEO, Yeon Ho LEE M y o n g Jun K I M v a T r a n T a m D a i hoc Quoc gia C h o n n a m G w a n g j u , H a n Quoc Tom tat: Axen tqo san xudt dupe coi la mot san pham thdi, no dupe tach xii ly va/hodc cdc dung dich thai nhieu nha may xir ly khoang Vd>c xir ly thdng thuong bao ham viec lam ket tua (long) de hinh nen phe thdi dn dinh cho viec loai bd hay tdi che che pham Axen Bdi viet de cap nen tdng cua vi$c ket tua As(V) va gioi thieu mot nghien ciru cy the xu ly tach nhd may xir ly nude thdi tai Cdng ty Kwangyang Ferro Alloy (KFA) Han Qudc Chuong trinh khdi phuc gan day dupe thuc hi$n tqi Md Giant, Canada ciing dupe gidi thieu nham the hien viec xir ly chat thdi Axen (AS2O3) sau ket thuc khai thdc Cdc khia canh co ban lien quan den su dn dinh vd ket tua Axen, tren cdng trinh thir nghiem tqi dqi hoc New South Wales bdi Robin dau thap ky 80 ve sau dupe md rdng cdc cdng tac phat trien xir ly cao hon bdi mot nhom nghien ciru tqi Dqi hoc Qudc gia Chonnam Su phat trien mdi lien quan den xir ly Axen dupe tqo nen tir qua trinh xir ly nude sinh hoat vd khdi chica Mo vd cdc kim loai khac dupe thao ludn nghien ciru Chuong trinh md hinh hda Stabcal (dupe phat trien bdi Montana Tech, My) dd dupe sir dung de khdo sat mire dq dn dinh (Eh-pH, log(ndng dp) so vdi pH) cua nhieu h? thdng As(V) Mire dd cd the du bao vi$c xir ly ket tua tqi nhieu dieu ki?n cua ty I? pH va Fe(III), Ca(II) hay Ba(II) hoac Mg(II)/As(V) va du bao nong dq can bang Axen cua dung dich lai sau ket tua Vi(>c xu ly dupe phat trien tqi Dqi hoc (Duoc gia Chonnam da dupe ung dung tqi mot nha may xir ly Mo tqi KFA, Kwangyang, Han Qudc Ngay bi tach Mg-As(V) cdc flowsheet khac Tac dqng ciia diiu ki$n dung dfch san xudt (dung dich ty I? pH, Fe(III) or Mg(II)/As(V)) dd dupe khdo sat de tdi uu hda dieu ki$n kit tua Dudi dieu kien tdi uu (ty 1$ pH, Fe(IJI) or Mg(II)/As(V) >3) As(V) cd the dupe tach khdi ddng xir ly den nhd hon mg/L Su ket tua ket tinh tot va se lam dn djnh cho viec loai trie va tdi che theo yeu cau Ca(II) va Ba(II) la khong thich hpp / » * * * r r ket tua As(V) cau tqo dn dinh cao ciia cdc chat kit tua CaMo0 va BaMo0 so vdi chat tuong ung vdi Axen Tic khoa: Axen, dn dinh, kit tua, phan img hda hoc, md hinh hda Gidi thieu • A x e n la m o t chat thai t h u o n g gap v a k h o x u l y , no k h o n g the b i pha h u y v a no c h i co the b i can bang hoa, bat d o n g hoa hay each l y de loai thai t r o n g m o t bai rac hoac kho chua T r o n g qua k h u , A x e n da d u o c su d u n g t r o n g cac thuoc t r u sau, t r u co v a t r o n g san xudt k i n h n h u n g h i e n no hau n h u b i g i o i han d u n g t r o n g h n h o p bao q u a n go D o n g - C r o m - A x e n A x e n d u n g t r o n g nhirng u n g d u n g bao h a m viec k h o n g k h i can t h i l t t r o n g viec x u l y chat thai v a l o a i bo, no co the d u o c k i e m soat v a bo sung m o t each de dang t r o n g cac hoat dong san xuat Chat thai tao tir cac hoat d o n g x i r l y k h o a n g v a k h a i k h o a n g la k h o x i r l y h o n , can quy m o h o n de l o a i thai S u t o n tai ciia A x e n sulphua hoa t r o n g t u n h i e n hau n h u la ket hop 672 nui ngni Cong nghiep r r icnoa hoc ki thuat md quoc te - 2010 md tien tien vi su phat trien ben viing v a i Fe dugc b i l t d i n t h o n g t h u a n g l a arsenopyrite (AsFeS) l i e n quan d i n k h o a n g san than va d i n g T r o n g k h i i t p h i b i l n h o n l a cac mat hang l i e n k i t v a i c a sa v a cac k i m l o a i c h u y l n t i l p n h u cobalt l a cobaltite ( C o A s S ) , d i n g n h u enargite ( C u A s S ) v a n h i e u chat khac A x e n sulphide n g u y e n chat t o n t a i n h u realgar (AS4S4 hoac P G S ) v a o r p i m e n t (AS2S) N h u n g k h o a n g c h i t gay n h i e m A x e n t r o n g n u a c n g a m t r o n g cac qua t r i n h d x y hoa k h u t u nhien hoac neu tiep x u c v a i k h o n g k h i t r o n g k h a i thac m o d o n g , t h a n da, v a cac k i m loai c a ban b i e n n h u c h i k e m , , m o l y p d e n , w , tao nen n u a c t h a i axit Cac k y thuat khac da dugc t h i l t lap d l l o a i bo A x e n k h o i n u a c n g a m , n u a c thai v a d u n g d i c h x u l y T i n h c h i t k h o a hoc k y thuat dang sau n h u n g k y thuat da d u g c de cap m o t each r o n g r a i t r o n g n h i e u cong t r i n h n g h i e n c u u (Jekel and Seith, 2002; M o h a n and Pitman, 2007; C h o o n g v a n.n.k., 2007; Sharma v a Sohn, 0 ) n h u dugc t h i h i e n bang Bang Cdc ky thuat dupe sir dung de tach As(V) vaAs(III) Cac k y t h u a t Dong dac va keo tu Adsorption on solid substrates Dien d$ng Mang loc, K h u muoi tham thau ngugc, IQC na no Su k i t tua ciia Fe(III)-Axenat hoac Fe(HI)-P0 -Axen ( A s ( V ) S\r k i t tua cua Fe(III)- axenit (As(III) Sy k i t tua cua Ca(II)-As(V) Su ket tua cua Ca(II)-As(III) Cac nhan xet quan tic cdc dung dich -, T h a m khao M c N e i l and Edwards, 1995; Gregor, 2001 Han va n.n.k.; 2002 Asta va n.n.k., 2009; Genc-Fuhrman va n.n.k., 2004; Martinez-Villafane va n.n.k., 2009 Sato va n.n.k., 2002; Shih, 2005; Geucke va n.n.k., 2009; Qu va n.n.k., 2009 Sato, 2002; Shih, 2005; Geucke va n.n.k., 2009; Qu va n.n.k., 2009; Nishimura va Robins, 1996; Fujita va n.n.k., 2008; Meng va n.n.k., 2000 Lenoble va n.n.k., 2005 Nishimura and Robins, 2008; Jain va n.n.k., 2009 Brown and Bothe, 1999; Raposo va n.n.k., 2004 Itakura va n.n.k., 2007 Mohan va Pittman, 2007 Choong va n.n.k., 2007; Wang va Mulligan, 2009; Sharma va Sohn, 2009 D o i v d i x u l y hoac d u n g d i c h thai cd chua i o n A x e n cao (hang t r a m p h i n t r i e u ) v a cac anion n h u sunfat v a clorua, viec s u d u n g hap p h u , trao d d i i o n hoac cac k y thuat m a n g de loai b d A x e n l a k h o n g h i e u qua n h u cac i o n k i t h o p v d i A x e n a t , c u t h i la A s (day g o i la A s ( V ) ) hoac arsenit, A s 3 - ( h o a c A s ( I I I ) ) a n i o n t r o n g qua t r i n h phan ly K i t hia la l u a c h o n tot nhat v e mat v a su x i i l y da d u g c s u d u n g r d n g r a i t r o n g thuc t l thuong mai N i s h i m u r a v a R o b i n s ( 9 ) l a n dau t i e n de xuat viec s u d u n g cua Fe ( I I I ) de ket h i a A s ( I V ) tir d u n g d i c h A x e n a t sat dugc c o i la d n d i n h nhat de x u l y ( M e n g v a n.n.k., 2000; Katsoyiannis v a Z o u b o u l i s , 0 ; L e n o b l e v a n.n.k., 2005; F u j i t a v a n.n.k., 0 ) T r o n g nha m a y thuc te, m o t l i e u l u g n g cua Fe ( I I I ) clorua hoac sunfat a p H 4)2 co the d u g c k i t tua t r o n g k h o a n g p H - l l , v o i h l i u h i t A s ( V ) d l loai bo i t h o n 0,8 p p m tai p H - , Cac c h i t d i n g k i t tua cua M g ( O H ) c i i n g d u g c d u doan l a tang p H tren p H , n h u t h i h i e n t r o n g H i n h 1(a) C» tren p H , k h o n g co k i t hia cua M g ( I I ) - A s ( V ) d u k i l n n h u t h i h i e n t r o n g ca hai so cac H i n h (a) v a ( b ) pH S P 10 12 H H Hinh Nong dp so vdi pH cua (a) Mg(II va (b) As(V) nhu dd du bao mo hinh kit tua sic dung Stabcal Cdc dieu kUfn kit tua: 469 mg/L (hope 0.0063 MAs(V)), 0.0188 MMg(H) vd 0.74 MMofVD tai 25 °C 5»| 500* , As(T) 10 11 12 Hinh (a) Hinh thdi cua As(V) dupe xac dinh bdi cdc xet nghiem ngung tu tqipH khac nhau, cho chat long tong hpp cua As(V) va As(III) (nhu cdc diim die lieu md) vd cho chat long Mo thuc (diim die li$u dupe dien) dtyl$ moi Mg/As khac (b) So sanh cdc hinh thai AS so vdipH dupe va du bao tie Stabcal, cho thay co chi hap phu cho viing pH thap (do H3M0O4 kit tua) vd khu pH cao (do Mn(OH) kit tua) Cac chat ding kit tua ciia hydroxit Mg (II) nhu thi giai thich thuc tl la hon As (V) co t h i d u g c ra tir d u n g d i c h , hoac bang each h i p p h u hoac d i n g k i t tua, h o n nua, no d u bao tir m o h i n h h i n h t h a n h Stabcal D i r l i e u t h u d u g c tir t h i n g h i e m k i t tua tai cac d i l u k i e n t u o n g t u , sir d u n g A s ( V ) t i n g h g p hoac d u n g d i c h thai M o co c h u a 0 M A s ( V ) d u g c 675 Hoi Cong nghi khoa nghiep md hoc ki thuat tien tien mo quui, vi su phat - < e triin u bin viing t h i h i e n t r o n g h i n h 2, cho thay A s ( V ) d u g c lay n h i e u h o n tir ca hai l o a i c h i t l o n g h o n n h u n g d u bao t u m o h i n h Stabcal t r o n g k h o a n g p H cao ( p H > 9) D o i v o i cac l o a i chat long tong hgp, k h o a n g p H thap cho thay s u g i o n g n h a u cua ca hai h i n h t h a i n o n g do, tuc la M o t n h u n g d u d o a n tir Stabcal v a no xac d i n h bang t h u n g h i e m T u y n h i e n d o i v o i chat l o n g that, viec l o a i bo cac A s ( V ) tai m o t p H < co the la hap p h u cua A s ( V ) vao ket tua H2M0O4 d u k i e n cho k h o a n g p H thap Su tach A s ( I I I ) tir d u n g d i c h b d i M g ( I I ) la k h o n g h i e u qua n h u tren hinh.2 Tai p H > , A s ( I I I ) co the d u g c tach k h o i d u n g d i c h b d i m o t chat hap p h u hoac c o che dong k i t hia ( b d i n g u n g t u M g ( O H ) ) Viec lira c h o n M g ( I I ) de ket tua A s ( V ) n h u m a gie axenat, Mg3(AsC>4) co dugc sau k h i x e m xet cac he t h o n g khac, d u g c biet den de tao nen cac chat ket tua o n d i n h h o n do hoa tan thap h o n san p h a m A x e n a t C o FeAsC»4, C a ( A s ) v a B a ( A s ) v d i gia t r i K la x l - ' x l s p - , 1.0xlO" 23 t u o n g u n g , so v d i 2.1 x - 2 cho M g ( A s ) So s a n h cac he t h o n g F e ( I I I ) - A s ( V ) , C a ( I I ) - A s ( V ) , B a ( I I ) - A s ( V ) v a M g ( I I ) - A s ( V ) 'ãVl a I Al (T, HAô02 - \ V V - g a \ - A \ B P 10 12 10 12 14 10 13 14 II pH Hinh Cdc sff on dinh cho cdc h$ thong khac nhau: va Ba(II)-As(V) Fe(IH)-As(V), Ca(II)-As(III) T u y nhien, t r o n g su h i e n d i e n cua i o n M O " , c h i l m u u t h i t r o n g d i l u k i e n x i i ly ( p H > 4) Ca ( I I ) v a B a ( I I ) se h i n h C a M o k h o n g hoa t a n v a t h i m o l i p d a t B a M o tren m o t dai p H r o n g , n h u t h i h i e n tren H i n h D i l u se p h u nhan viec sir d u n g cac ion d l loai bo A s ( V ) tir cac l o a i c h i t l o n g x i r l y M o D i v d i Fe no c u n g la cung d u g c b i l t d i n v d i viec l o a i bo cua A s ( V ) b d i Fe ( I I I ) la c h u y l u la h i p t h u , v a su h i n h cua 676 noi ngni Cong nghiep r r Knoa hoc kT thuat md quoc te - 2010 mo tien tiin vi su phat trien ben vung scorodite o n d i n h h o n d l xu* l y c h i co the dugc thuc h i e n d nhiet cao h o n ( F u j i t a v a n n k , 2008) Cac chat Fe I n d i n h ( I I I ) dugc m o h i n h hoa v a d u g c the h i e n t r e n h i n h l a Fe203 D i l u k i e n : 0 M A s ( V ) - M F e ( I I I ) hoac C a ( I I ) hoac B a ( I I ) - M M o ( V I ) Xu* l y A x e n t a i M d G i a n t , C a n a d a - M o t c h u o n g t r i n h k h d i p h u c c h a t t h a i r a n (http://en.wikipedia.org/wiki/Giant Mine) M d Giant l a m o t m d vang l d n n a m gan Y e l l o w k n i f e , Northwest Territories, Canada, b i t dau san x u i t vao n a m 1948 v a ngirng hoat ddng vao n a m 2004 N d dugc san x u i t tren 7.000.000 oz (220.000 k g ) vang tren thap k y hoat ddng T u y nhien hoat ddng khai thac tao mot trach nhiem to I o n v l m d i t r u d n g , nd cd t h i v a n d n h i e m A s l a l d n n h i t tren t h i g i d i , m a cac chu sd h u u m d t r u d c day d l l a i cho c h i n h q u y l n Canada v a T a y B i c d l giai q u y l t Cac m d k h l n g Id da phai x u l y 237.000t ciia t r i d x i t A x e n ( A s ) b u i sinh n u n g arsenopyrite B u i tan nude v a chua khoang % A x e n 950ha cdng t r u d n g bao g d m m d I d thien, hao khai thac quang dudi, 0 m d i t b i d n h i e m v a khoang 100 toa nha bao g d m ca t l hop nha nung/ddng g d i b i d n h i e m r i t cao b i nhiem A x e n v a sgi amiang M o t d u an k h d i phuc $400,000,000 dugc tai t r g cua c h i n h p h i i dang dugc t i l n hanh d l giai q u y l t van d l (http://www.ainc-inac.gc.ca/ai/scr/nt/cnt/gm/ab/abp/index-eng.asp) Cac tridxit A x e n , m a trudc da dugc ddng cung h i m m d d u d i long d i t va d u d i ldp bang vinh cuu t u nhien T u y nhien hoat ddng khai thac lien tuc, cac ldp bang v i h h cuu b i t dau tan N u d e m d chua A s ro r i khdi l u u t r u d u d i long d i t , d nhiem nude n g i m ciia k h u vuc Trong D e an khac phuc hau qua (hinh 3, chep tir trang web d tren), 15 ham m d va g i l n g d i i n g dang dugc ddng Thermosyphons ft ciing b d i m o t he t h i n g nhan tao, sir dung CO2 n h u la c h i t l a m lanh D u n g dich C dugc dua x u d n g thdng qua m o t ong de lam lanh v i i n g d u d i ngam v a cac k h i nong sau dd tang len den b l mat thdng qua xi-phdng nhiet hoat ddng, dugc cd t", dac va dugc dua x u d n g m o t lan nira D u kien sau thdi gian ban dau, se khong cd them nang l u g n g can t h i l t cho su ddng b5ng ciia k h u vuc d u d i l o n g d i t D i l u mot phan chi p h i d u an $200,000,000, mot nira s i phan bd cho chuong trinh k h i c phuc va se m i t 10 n a m (tir 2007) d l hoan m n h c d - < > Phuomg phap block each ly dupe sir dung c As a > vinh viin dudi long ddt va de ngdn nude tu ldp bang vinh cuu G i a n t C a n a d a d e l u u t r i t h f f n M t h n tham D i t b i d n h i e m t r e n m a t d i t cung dugc t h u thap v a giri d i n m o t h i m d u d i l o n g d i t , cung phai d u g c d d n g c u n g bang each sir d u n g P h u o n g phap b l o c k D d n g c i i n g m d ta d tren 100 toa nha tren m a t d i t c u n g da d u g c t i e u h u y v a c h i t t h a i c i i n g v d i cac l o a i da t h a i tir khai thac m d se d u g c g i r i d i n cac h i m d u d i d i t d l d d n g c u n g M o t v d boc c h i t t h a i x a y d u n g cho m d k l tir n a m 1944 c i i n g da d u g c x i r l y bang each bao p h i i v d i m o t l d p d i u t i e n cua m d da sdi hoac da M o t l d p v a i d i a k y thuat k h o n g det dugc dat d p h i a tren v a d u d i l d p sdi d l t r a n h n u d e t h i m vao vat l i e u t a i l i n g 677 Hdi Cong nghi nghiep khoa hoc md tien ki thuat tien md quoc vi su phat xe - triin bin zuiv viing M o t l o p ho t r g t h a m thuc vat (30-70 c m ) sau d u g c dat len Surface to be vegetated tren ( c u n g v o i m o t l o p v a i dia k y Surtao* sky {mm 6%; max 33%) thuat k h o n g co k i e n true ro rang, tach no v d i cac l d p sdi) tir tham Lop thyc vijt h.6 Hai ldp bao phu Capillary Break Tailmos 30-70 cmstftor V iiSyciay thuc vat c d the phat t r i e n tren d i n h (hinh.3 ( b ) Ket luan 16-30 cm gravel i Viec loai b d A s tir viec xir l y va or 30-60 cm screened crwh (c xir ly ddt dd thdi - duoc bao bgc vdi l&p sdi (15-100 cm) vd bun hay ddt set (30-70 cm), vdi kien true khong dettirgiiia, trudc thuc vqt chat A s M d h i n h Stabcal cd the dugc » r r dung de d u bao cau tao chat A s ( V ) khac nhau, v a cho du dd la kha thi v o i su cd mat cua cac to hop khac manh n h u ( M o - ) m o l i p d a t M o t danh gia khoa hgc quan ve chii de da dugc dua ra, bao g d m ca viec x i r d nhiem A s m o t d u an hien ( t a i m d Giant) tai Canada, Tdi lieu tham khdo A n , J.W., Lee Y.H., Tran, T., K i m , S.J Lee S.O and K i m , M.J., 2009(a), Production of high purity molybdenum compounds from a Cu-Mo acid-washed liquor using solvent extraction, Part 1: Laboratory studies, Minerals Engineering, 22, 1020-1025 An, J.W., Jung, B.H., Lee Y.H., Tran, T., Kim, S.J and Kim, M.J., 2009(b) Production of high purity molybdenum compounds from a Cu-Mo acid-washed liquor using solvent extraction, Part : Pilot and plant studies, Minerals Engineering, 22,1026-1031 Asta, M.P., Cama, J., Martinez, M and Gimenez, J., 2009, Arsenic removal by goethite and jarosite in acidic conditions and its environmental implications, J Hazardous Materials, 171,965-972 Brown, P.W and Bothe, J.V., 1999, Arsenic immobilization by calcium arsenate formation, Environmental Science & Technology, 33, 3806-3811 Choong, T.S.Y, Chuan, T.G., Robiah, Y , Koay, F.L.G and Azni, I , 2007, Arsenic toxicity, health hazards and removal techniques from water: an overview, Desalination, 2007, 217,139-166 Fujita, T., Taguchi, R., Abumiya, M Matsumoto, M Shibata, E and Nakamura, T., 2008, Effects of zinc, copper and sodium ions on ferric arsenate precipitation in a novel atmospheric scorodite process, Hydrometallurgy, 93, 30-38 Genc-Fuhrman, H., Tjell, J.C and McConchie, D., 2004, Increasing the arsenate adsorption capacity of neutralized red mud 03auxsol), J of Colloidal and Interfacial Science, 2004,271,313-320 Geucke, T., Deowan, S.A., Hoinskis, J and Patzold, C , Performance o f a small scale RO desalinator for arsenic removal, 2009, Desalination, 239,198-206 Han, B., Runnells, T., Zimbron, J and Wickramasinghe, R., 2002, Arsenic removal from drinking water by flocculation and microfiltration, Desalination, 145, 293-298 Huang, H.H., 2008, Stabcal-Stability calculation for aqueous and non-aqueous systems, Monttana 678 tioi Cong nghi nghiep khoa hoc md tien ki thuat tiin md quoc vi su phat te - 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