AMH QTCN NU LUYN KIM LOI & HP KIM L 80 TN

TRNG I HC BCH KHOA TP. HCM

KHOA CNG NGH VT LIU

AMH QTCN NU LUYN KIM LOI & HP KIM

Mc lc Mc lc... Li ni u.. Chng 1 : Lch s l h quang . Chng 2 : Tnh hnh trong nc .. Chng 3 : Tng quan v l h quang ... Chng 4 : Thit k kch thc l .. Chng 5 : Tnh ton phi liu .. Chng 6 : To x ...

Chng 7 :Qu trnh nu luyn .. Chng 8: Kt cu thng rt..

LI NI UNgy nay cng vi s i ln ca t nc, ngnh cng nghip ng vai trht sc quan trng p ng cc yu cu cho ngnh kinh t quc dn: ckh, xy dng, ha hc do ngnh cng ngh vt liu cng pht trinnhanh chng p ng cc yu cu pht trin chung ca t nc. Trong ngnh luyn kim c v nh xng sng ca quc gia. m trchvai tr quan trng ny, mi ngi k s vt liu tng lai nht thit phi hiuv nm r bn cht ca qu trnh luyn kim, cc thit b l, thnh phnnguyn vt liu, thnh phn xV bit vn dng nhng kin thc hc vothc tin, gp phn vo s pht trin ngnh luyn kim ni ring cng nhngnh cng nghip nc nh ni chung. n mn hc l mt phn thit yu ca chng trnh gio dc ca i hc Bch khoa Tp H Ch Minh, l c hi sinh vin bc u p dng vo thc t cc kin thc hc c cng nh l mt c hi tt sinh vin gt hi c cc k nng mi, kin thc thc t mi. Thc hin n mn hc chnh l c lm quen cch thc hin lun vn tt nghip sau ny. D sao th vi t cch l mt sinh vin v cng ch ln u thc hin nn khng th trnh khi cc sai st, nhng cng l mt qu trnh di tm ti v c gng, em rt mong c thy ch bo nhiu hn. n ny c thc hin di s ch dn tn tnh ca thy Thng. Em xin cm n thy rt nhiu v knh chc thy nhiu sc khe tip tc s nghip cao c ny.

Chng 1: LCH S L H QUANGL h quang c pht trin bi Paul Hroult ngi Php v ng dng trongthng mi bi ngi M nm 1900. Ban u ch yu dung nu thp dng c v thp l xo. Sau chin tranh th gii ln II, nhu cu v thp hp kim cht lng tng cao: thp khng g, chng mi mn c hc, va p, thp c tnh n hi cao m l Besmer, l Mactin, l thi khng kh khng p ng c. V vy phi chuyn sang dung l in nh l h quang, l cm ng, l in x, l plasma

L h quang in c s dng rng ri nu cc loi thp cacbon cht lng, thp hp kim thp , trung bnh v cao vi sn lng ln. Sn lng l h quang chimn 80 90% tng sn lng thp l in, 33,1% tng lng thp (nm 2005). Dung lng l ban u ch vi n vi chc tn, ngy nay ngi ta s dng ph bin cc loi l 100 400 tn/ m. u im ca l h quang l c th dng nguyn liu t st thp ph liu. iu ny gip tit kim nguyn liu, nng lng nn t hiu qu cao v kinh t v mi trng. L h quang c ci tin lin tc v cng ngh: p dng cc bin php cng hanh phng php thi oxy, than, s dng ch in siu cng sut, s dng l hquang 1 chiu siu cng sut, nung liu trc khi nu chy hay s dng l h quangthn ct ( SF) Kt qu l: -Tiu tn in nng gim dn t khong 630 kWh/tn xung di 350 kWh/tn. -Thi gian nu gim t 180 pht xung c th cn 45 pht. -V hng lot ci tin khc nh c kh ha, vi tnh ha, dng nc lm ngui tng v np l, to x bt, kt cu l theo kiu tho y lch tm (EBT), ophi gip tng tui th l v cht lng thp.

Chng 2: TNH HNH TRONG NCCh tiu kinh t k thut trong sn xut thp l h quang trong nc rt thp v tiu hao vt t cao ( bng ch tiu ca th gii nm 1970), nng sut lao ng thp do: -Cht lng thp ph khng tt, t trng ng thp nn phi np liu nhiu ln,lng x tng, hiu sut thu hi thp thp, thi gian nu luyn tng. -Ngun cung cp st thp khng nn khng pht huy ht cng sut ca l. -Dung lng l qu nh, nhiu l, b tr ri rc nhiu nh my. -L din hay gp s c do l c, thit b khng ng b.

Bin php khc phc:

-Gia cng ph, ct thp ph tng t trng ng, lm sch thp ph. -Thi oxy v phun than bt gim thi gian nu. -u t l thng LD gim thi gian tinh luyn. -Dung gang lng t l cao b vo phn thiu ca thp ph nn tng cng sut l. -u t h thng lc bi, gim nhim mi trng. -Quy hoch li cc nh my, tp trung li, b cc l nh,ci to cc l trung bnhthnh ln, u t xy mi cc l c ln v hin i 100 400 tn. -p dng cc bin php c kh v t ng ha cao vo khu cht liu, v l, co x tng nng sut v an ton lao ng, gim thi gian nu luyn. -Thu ht cc d n u t nc ngoi vo lnh vc luyn thp theo cng ngh tin tin hc tp cng ngh v k thut

Chng 3: TNG QUAN V L H QUANGI/ Cu to l :- V l: Bn trong v c xy hoc m vt liu cn nhit v gch chu la. V l l in h quang gm c v ngoi bng thp chu nhit, c dy 10mm n50mm. V l cn c cc gn tng bn v c cc vnh ai d gi nguyn hnh dngca v l. Vnh ai pha trn lm thnh dng rnh, cha ct to kht khi yy l lm dng chm cu bo m cho v y l c bn ti a v lp lt ctrng lng nh nht. V y l lm bng thp khng c t tnh c th lp tcc thit b khuy trn bng in t. - Thn l : hnh tr, y cong hoc y phng, hay than dng hnh cn y cong.

Trn thn l c np y kn c nh hoc di chuyn c khi cht liu vo l theo phong php t trn xung. - Np l : khng c v bc kim loi, nhng m bo cng v bn, ngi ta lm mt vnh ai kim loi m kn chn vm np.

II/ Vt liu xy l :-L h quang baz thng c xy bng gch manhezit ( MgO), cromit - manhezit (Cr2O3- MgO), manhezit-cromit ( MgO - Cr2O3), cng c khi dng alumin cao xy np l. Ngoi ra cn s dng gch samt cn nhit v gi nhit -Gch manhezit c dng xy phn trn ca tng l v phn y l, thnh phn ha hc : MgO = 86%, CaO = 2%, FeO = 5%, Al2O3 = 1.5%, MnO = 0.8%, v SiO2 = 4%. Gch manhezit c chu la cao 1700 n 1800oC, nhit bt u bin mm 1500oC, v dn nhit li cao, nhng gch ny li c tnh bn nhit km hay b nt v khi nhit thay i t ngt, do ngi ta khng s dng xy np l v chn tng l. -Gch crom-manhezit c thnh phn ha hc : Cr2O3 = 20% n 30%, MgO = 40 n 45%. Loi gch ny c chu la cao, dn nhit tt, v chu c s thay i nhit t ngt, do ngi ta dng xy chn tng l, ch tho thp..

-Gch manhezit-cromit c thnh phn ha hc MgO = 65 n 70%, Cr2O3 = 8n 18%. Loi gch ny c ng dng ph bin xy np l. -Gch samt, l loi gch c tnh cht trung tnh, thnh phn ha hc gm : Al2O3 = 20 n 30%, SiO2 = 55 n 60%. Thng dng loi gch ny xy lp cn nhit ngoi cng y, mng rt thp v ni lt thp.

III/ B phn c kh ca l :-V l: thng c hn bng thp tm vi chiu dy t 16 -50(mm) ty vodung tch ca l, thng th ngi ta chn chiu dy lp v bng 1/200 ng knhl . V phi c bn c th chu c trng lng kim loi v lp lt, ng thi phi chu c p sut ca lp lt khi b gin n nhit. Do v l c hnh dng chm cu c c bn ti a v lp lt nh nht.

-Vng m in cc : c loi t ng trn np l, c loi dng ng xon rut g , c loi kiu i trng , nhim v ca cc vng m ny to s kht cht gia cc in cc v np l trnh hin tng in cc b gy dn n vic tiu hao in cc v gi thnh thp. B phn cp in cc : thng lm bng thp ng thau hoc ng thanh. B phn cp in cc dng dn in n in cc v gi in cc mt cao nht nh . Ngi ta thng gim in tr tip xc gia u cp v in cc nhm gim mt mt in nng. V lm vic trong mi trng khc nghip nn b phn cp in cc phi c bn cao v mt mt nhit l nh nht.-B phn cp in cc : thng lm bng thp ng thau hoc ng thanh. Bphn cp in cc dng dn in n in cc v gi in cc mt caonht nh . Ngi ta thng gim in tr tip xc gia u cp v in cc nhmgim mt mt in nng. V lm vic trong mi trng khc nghip nn b phncp in cc phi c bn cao v mt mt nhit l nh nht.

-B phn c kh nng h in cc : nm trong mi in cc, mi b phn gm 1 ng c in, khi ng c quay th u dy cp ko b phn in cc ln xung, u dy cp kia ni vi i trng . i trng c dng cn bng t 70 -80% trng lng ca in cc , dm ngang , ct chng v cp mm , do b phn nng h in cc i hi cng sut nh . Thng c hai loi b phn nng h in cc : loi tr thng ng c nh c xe trt trn n, loi c ct trt vo nhau -B phn c kh nghing l : phi m bo vic nghing l phi m , khng va p, c th nghing 450 rt kim loi vo thng , rt v nghing 10- 150 v pha ca npliu tho x. C th iu khin tc nghing mt cch d dng, gim bt vic di chuyn, thng rt nhiu ln trong qu trnh rt. Pha t v tr an ton, khng b kim loi phun bn. C hai loi c cu nghing l chnh : b phn nghing l t bn hng v b phn nghing l t di y. Vi l h quang 50tn, ta dng b phn nghing l di y. B phn ny c cc u im sau : nghing l vng chc, m, u v t ng hon ton, khng nh hng n khu vc lm vic ca cng nhn khi nghing khng lm lch tm l. Bn cnh , cng c cc nhc im nh : hay b ri x, kim loi lng ln ng c, thng xuyn m bo m sch s v kh ro khu vc t b phn c kh nghing l th n mi c th hot ng tt, trc khi l chy cn c ngi kim tra in cn thn. B phn np liu : c hai phng php np liu : dng my np liu v dngthng np liu. Vi l h quang 100 tn, ta khng s dng dng my np liu m dng thng np liu. y l phng php ch yu c dng trong cc lo hin i. Liu c np vo l t mt thng

liu pha trn ca l. Hin nay tt c cc l h quang hin i u c thit k theo kiu np liu t trn, phng php ny honton chnh xc Ngoi cc b phn c kh ch yu ni trn, trong l h quang cn c cc b phnph khc nh c cu nng np l, c cu quay np l, c cu quay thn l v bphn lc sch kh l. Trong cc l bnh thng, in cc s to nn 3 hsu trn mt liu trong qu.trnh nu chy, cn phn liu xa in cc th chy chm hn. Do cng ha qu trnh nu chy liu rn v trnh cho y l khng b qu nhit bi h quang th ngi ta c b phn quay thn l.

Chng 4: THIT K KCH THC L1. Xc nh th tch ni l : Mt tn thp chim 1 th tch l 0,145m3 (th tch ring ca thp l Vokl = 0,145m3/tn) Mt tn x chim th tch l 0,333 m3 (th tch ring ca x l Vox 0,33 m3/tn) V l h quang dng x baz v c dng gang trong phi liu nn chn g x = 0,15 g KL Nn th tch l: V = Vkl + Vx = gkl . Vokl + gx . Vox V = 80.0,145 + 80.0,15.0,33 = 15,56 ( m3) 2. Chiu su v ng knh ni l: Khi tnh ton cn cc iu kin sau : Hnh dng ni l : cu cn

Mc x lc oxi ho trng vi mc ca s cht liu v c D/H = 5 vi D, H l ng knh v chiu su ca ni l Chiu cao phn l l hnh cu : h1 = 0,2 H Th tch ni lV=h23R2+Rr+r2+h1r22+h126

Vi R = D/2, r = (D 2h3) = 1,7 H, nn ta c: V = 12,1 H3= 15,56(m3) Chiu su ca ni l: H = (15,56 / 12,1)1/3 = 1,087 (m) = 1087 (mm) ng knh ca ni l: D = 5H = 5435(mm) Bn knh ni l: R = D/2 =2718 (mm) Kch thc phn cong hnh cu y l: d = 3,4H = 3696(mm) Chiu cao phn l l hnh cu : h 1 = 0,2 H = 217 mm Chiu cao h2 : h 2 = 0,8 H = 870 (mm)

3. Kch thc khng gian nu luyn : Chn tng ca l thng lm cao hn mc ca np liu t 100 200mm xkhng tip xc vi lp gch xy ca tng l. ng knh ca khng gian nu chyc tnh mc ny. Ta c: DKG = D + 200 = 5435 + 200 = 5635 (mm) Chiu cao t ngng ca s n ming trn l : H1= (0,4 0,45 ) DKG Khi xc nh chiu cao ca khng gian nu chy H1 t ngng ca liu n chnnp l cn ch cc c im sau : chiu cao tng l H1 m tng th tui th np ltng theo do xa ngn la h quang, ng thi nu luyn c liu nh, th nhng bmt mt mc nhit ca l s tng ln. Tuy nhin ngi ta thng cho np l xa b mtkim loi v s gim c thi gian dng l tu sa v ci thin c mt s ch tiukinh t k thut H1 = 0,45 DKG = 2536 (mm) nghing ca tng l ; x=H1-10010=2536-10010=243,6(mm) ng knh khng gian nu luyn D1= DKG + 2x=5635+2.243,6=6122(mm) Chiu cao vng np l :h3=DKG8=704(mm)

Chiu cao tng cng t mt kim loi n np l l H2 : H2 = H1 + H3 = 2536 + 704 = 3249 (mm) ng knh np l: D1 = 10 H3 = 10 . 704 = 7040 (mm) ng knh y ni l: d = D 2h2 = 3,4 H = 3,4 . 1087 = 3696 (mm) ng knh trong DT = DKG+ 2.tng= 5635 + 2. 600 = 6835(mm) Chiu dy lp thp thp = (1/200 1/250).DT = 27,34 34,17 ta chn thp = 30(mm) ng knh ngoi DN = DT + 2. thp = 6835 + 2.30 = 6895 (mm) Chiu rng ca l: bc = (0,2-0,3)DKG = 1408(mm)

Chiu cao ca l: hc = (0,7-0,8)bc = 1056 (mm) dy np l :np l=340(mm) dy tng l tng l=520-620 (mm) dy y l : y l= 850 (mm)

Chng 5: TNH TON PHI LIUNu Luyn Thp 14CrMnSi Thnh phn mc thp: Mc C Cr Mn Si P S Cu Ni

14CrMnSi

0,11-0,16 0,14

0,5-0,8 0,65

0,9-1,2 1,05

0,4-0,7 0,55