HOI NGHI KHOA HOC KY THUAT MO TOAN QUOC LAN THUf XX
CNM
:Ai- :
S A N G P H A N LOAI T H A N CAP HAT MjN VA TACH NUIDTC THAN TIJTBUN BANG MAY SANG RUNG TAN SO CAO
KS. LE DUY THANH, CN. NGUYEN MINH TU Cong ty cophan CNCB khoang san Viet Due KS. LA HONG DL/C - Vien Khoa hgc Cong nghe Mo-TKV
1. Sang phan loai than cap hat mjn 1.1. Nguon gdc, tinh chat than cap hat mjn Than cap hat min (<500 |im) duoc sinh ra trong qua trinh khai thac hoac do bj vd vun trong qua trinh van chuyen, bdc rdt, sang tuyen than.... Lay chat lUdng than xua't khau tren the gidi hien nay cd do tro khdng Idn hdn 12 % lam can CLT de xac djnh chat luong than cap hat mjn-pha "tdi han", cd do tro >12 %. Tuy tC/ng md cd the phan tach chat luong pha "tdi han" theo cap hat khac nhau nhu: 45 l^m, 100 \im hay 150 ^m..., theo nhu cau cua thj trudng. Van de la can phan tach dUdc chung de thu hoi san pham cd chat luong cao ma tCf trudc den nay dang bj that thoat.
1.2. Sang phan tach than cap hat mjn
Hien nay tren the gidi chua cd cdng nghe sang phan tach than cap hat min < 500 nm dat hieu qua cao ve chat lUdng va kinh te, nhutach bun than ci!ia cac nha may tuyen. Vi the, cd tCf 10-4-15 % than cap hat mjn bj that thoat, lam tSng gia trj dau tu va gay d nhidm mdi trudng... NhiJng cdng nghe phan tach than cap hat min hien nay nhu sau.'
• Sang rung thdng thudng (sang tan sd tha'p- mot tan so).
• Tuyen xiclon thuy lyc (xoay ldc thijy lyc).
• Thie't bj mang xoan (phan li vit xoan).
a. Sang rung thong thudng: Khdng the sang phan loai cap hat nho hdn 500 (.im. Chu ye'u sang phan loai dai cap hat Idn de'n Idn nha't (ty cap hat 10-^100 mm), cdng suat thap, chat lUdng phan tach tha'p. Ve nguyen tac, sang loai nay khdng nang cao dUdc chat lUdng than. De dau tu mdi, cdng nghe nay hau nhu it dUdc sCr dung tren the gidi.
b. Tuyen xiclon xoay idc thuy life: Cd cdng sua't cao, nhung thiet bj rat dat. San pham phan tach khdng triet de. Cap hat Idn l i n trong than cap hat nho se anh hudng de'n chat luong tuyen nd'i khi tach cap hat nhd va chi phi thudc tuyen noi se tSng len 2 lan hoSc Idn hdn (ty 2,5 USD/tan than, tang len de'n 5 va cd khi den 8 USD/tan than tuyen).
c. Phan tach bang mang xoan: Cdng nghe phan
tach cap hat bang mang xoan khdng hoan thien.
Chat lUdng phan tach tha'p, ve nguyen tac, khdng the phat trien cdng nghe nay de phan tach than cap hat mjn hien nay.
1.3. Cdng nghe phan tach than cap hat mjn tren sang rung tan so cao Ultimate Sereener™ (sang "iy
tudng") so sanh vdi sang rung thong thifdng 1.3.1. Sang rung thdng thu&ng
Nguyen ly lam viec. De kich hoat dUdc ludi sang lam viec, sang rung thdng thudng phai kich hoat toan bd ke't ca'u cCia may. Mud'n dat hieu qua sang cao, ludi sang, phai lam viec vdi gia td'c Idn de'n 16.G (G - Gia td'c rdi ty dd, G=9,8 m/s^). Vi the, mot lyc Idn tai trong lien tuc tac ddng de'n toan bo than vd may, ke't qua, sdm muon thie't bj de bj bung ra.
Do dd, sang rung thudng chi cho phep lam viec vdi gia td'c gidi han trong khoang 4+5 G, m/s^, nen cdng suat va chat lUdng sang tha'p.
Khd'i lUdng Idn cac hat trdn ludi sang, chi dUdc ki'ch hoat dung bang tan sd cua ludi dien cung cap.
Vdi tan sd kich hoat nay, cac hat chi duoc trdn chu ye'u tren be mat ludi sang, mot sc hat di qua ludi sang dudi tac dung ci!ia trong lyc.
Thye chat, sang rung thdng thudng khdng tac dong gi de'n vat lieu vao sang ma chi thy ddng tron chung tren be mat sang, doc theo phUdng nam ngang, dan de'n vat lieu se bj dinh bet, ddng tu lai, Idp nay chcng len Idp kia, khd phan tach duoc.
Bat budc phai cd thie't bj phu trd khac de lam sach mat ludi sang (nhu dung ban chai, may thdi khi, may tao sdng lUdn...). Chi phi van hanh se tang len. Thye chat thi sang rung thdng thudng khdng the goi la may sang.
1.3.2. Sang rung tan so cao
Sang rung tan sc cao la tie'n bo khoa hoc, ky thuat mdi nha't hien nay, la cudc each mang trong cdng nghe sang rung, duoe coi la may rung tieu chuan mdi
"ly tudng" (Ultimate Sereener™) de phan tach vat lieu dang khd hay udt (sau day gci la sang "ly tudng").
• Nguyen ly lam viec: Sang rung "ly tudng"
khdng khac nhieu sang rung thudng, nhung dugc
Y^n^^j
CONG NGHIEP MO SO 6 - 2009HQI NGH! KHOA HOC KY THUAT MO TOAN QUOC LAN THUT XX
trang bi mdt he thdng kfch hoat thfch Qng tan sd cao cong hu'dng. Tao rung bang dong cd dien (dong Cd rung) vdi tan sd cao thfch yng, cd the tang hon 200+400 lan, dUdc bie'n dd'i ty mot tan sd (dieu hda) thanh nhieu tan sd (khdng dieu hda) kich hoat ludi sang lam viec.
Tai thdi diem tan sd kfeh hoat ngoai (tan sd eua may) trung vdi tan sd kfeh hoat rieng ci!ia vat lieu, se tao ra hien tUdng cdng hudng. Tao dUde hien tUdng cdng hudng, vat lieu dUdc khuay tron b myc cao nha't vdi lyc tac ddng tha'p nha't (lyc tac ddng tren be mat ludi sang tha'p). Dieu dd lam eho sang
"ly tudng" ed hieu sua't cao va tang hdn de'n 30 %'.
Cac hat vat lieu vao sang "ly tudng", nhanh chdng "tie'n den die'm" kich hoat tan sd rieng.
Nhd tan sd eao eCia he thd'ng truyen de'n ludi sang lien tuc, day dac nhieu tan sd quang phd' Idn khae nhau cung mdt luc. Theo dd, cac dang tan sd khac nhau dugc phan bd tren be mat ludi sang thay ddi vdi tan sua't ty 16+25 lan/s va tUdng yng la nhung sdng quang phd' dai lam cho sang rung "ly tudng" quet dugc toan bo be day Idp vat lieu tren ludi sang, Idp vat lieu dugc xdi tung len ("sdi" len) eung mdt luc, tao ra mot khoang vdi be mat ludi sang, Idp nay each 1 mm, Idp kia each 1,1 mm va Idp khac each 1,2 mm...
va khdng he bj dinh bet va ty lam sach.-
Sang "ly tudng" lam viec vdi gia td'c ty 300. G den 1000.G, m/s^ va cd the' cdn Idn hon, (H.1). Gia td'c lam viee eCia sang rung "ly tudng" gap 75+250 lan sang rung thdng thudng, nhung khdng lam tang do rung cua than may.
Do rung than may cCia sang "ly tudng" tha'p hdn bat ky sang rung nao va theo bien do dao ddng th^ng dyng xae djnh duge tha'p hon 1,2 den 1,5 lan.
Tai trgng len than may tha'p, ke't cau ggn nhe, tud'i thg ciia sang rung "ly tudng" se cao hdn bat ky loai sang nao. Nguyen ly nay, cac sang thdng thudng khae khdng the ed duge.
Gia td'c Idn ke't hgp vdi kfch hoat tan sd cao, sang rung "ly tudng"cd the sang duge bat ky loai vat lieu nao vdi edng sua't Idn. He thd'ng rung tan sd cao cgng hudng, ung sua't lyc len ludi sang thye te khdng xay ra, ludi sang khdng phai keo cang, tud'i thg cao.
Sang "ly tudng" lam viec vdi bat ky loai ludi nao (sat, nilon, polyeste...), vdi bat ky kfch thudc Id (ty 2 ^m de'n 30 mm), vdi bat ky vat lieu nao khd hay Udt, trong bat ky cdng doan nao (tach am bgt ca phe 27 |j.m, rCra than cue 30 mm) eua nhieu nganh cdng nghiep khac nhau.
1.3.3. Tinh UU viet trong van hanh may sang rung "ly tuang"
•:• Sang "ly tudng" hon h i n ve tfnh nang va cdng sua't Igc tach - hdn 1 den 10 lan sang rung thdng thLfdng.
• Hieu sua't bao hanh ty lam sach iLfdi sang trong qua trinh iam viec vdi bat cy loai vat lieu nao vao sang khd hay udt.
•> Sang dugc vdi khoang ed hat dao ddng Idn (ty 10 ^m de'n 30 mm). Phan tach dugc cae cap hat mjn, tie't kiem dugc khd'i lugng Idn san pha'm trudc day khdng thu hoi duge.
•:• Sang dugc vdi pha cap hat mjn hdn nhieu so vdi sang trudc day cd the sang dUdc.
• Cd the sang dugc loai vat lieu khd sang nhat ma trudc day khdng sang dugc.
• Tudi thg cua ludi sang eao-gia ludi sang tha'p -thay ludi ddn gian.
• Tfnh kinh te de thay the hdn han so vdi ta't ca cac loai may sang phan tach khac (ly tam, Ige, phan tach ca'p hat bang khdng khf, xyclon...). Cdng nghe phan tach cap hat hoac tach nudc pha ran ty huyen phu cua cac vat lieu thi khdng cd ba't cy loai may nao ed the so sanh dyge vdi may sang rung "ly tudng".
<f Chi phf de phan tach ca'p hat hoac tach nudc, giam nhieu lan so vdi ba't cy loai thie't bj nao khac.
<•" Van hanh don gian, khdng khae vdi sang thdng thudng,
•:• Khdng cd them ba't cy loai thiet bj nao ve dien, thuy lyc, khi nen trong qua trinh van hanh (chi cd ddng cd rung dae biet nhu sang thdng thudng).
Sang thong IhuShg Sang"iy tuflng"
sang thong thLfing
sang "ly tu6ng"
H. 1. Dd thi lam viec so sanh glUa sang rung thudng va sang rung "ly tudng".
•:• Khdng can de'n nguon cung cap dien khac.
• Khdng them eae bg phan quay nao khae (chi ed dgng cd rung)
• Khdng can bat ky thie't bj nao de lam sach ludi sang (ludi sang khdng bj dfnh bet).
Tdm lai, sang "ly tudng" la may duy nhat dap Lfng dugc cdng nghe phan tach cap hat mjn va tach nLfdc triet de ct!ia cac vat lieu, thye hien dong thdi tren eung mdt may, cd the tuy chgn theo ca'p hat mong mud'n, an djnh dugc cdng sua't va cha't lugng san pham.
CONG NGHIEP MO SO 6 - 2 0 0 9
Hdi NGHI KHOA HOC KY THUAT MO TOAN QUOC LAN THIjrxX
CNM
1.3.4. So sanh sang "ly tuang" vdi sang thong thu&ng
Khdng the so sanh dugc bdi cdng sua't sang "ly tudng" rat eac, nen sd lugng may can ft hdn sang thdng thudng khi eung sang mgt khdi lugng nguyen lieu nhu nhau. Ve kinh te se:
• Tie't kiem dugc mat bang san xua't.
• Tie't kiem dugc chi phf nang lugng.
••• Giam sd lugng cdng nhan van hanh, khdng can cdng nhan lam sach be mat ludi.
• Giam chi phf dau tuxay dyng...
1.4. Ke't qua sif dung sang rung "ly tudng"
tren the gidi
Hien nay sang "ly tudng" duge trien khai trong
cdng nghiep than b Nam Phi, Oe, My, Nga, Thd NhT Ky, Tay Ban Nha... Sang tach than, tach nLfdc vdi pha "tdi han" (do tro de'n 12 %) ty bun than eCia tyng xf nghiep. Ke't qua dat dugc nhutren Bang 2.
Ty dan chyng tren, cho tha'y sang "ly tudng" la thie't bj duy nhat hien nay dap yng sang phan tach vat Ijeu cd cha't lugng cao nhat, khdng phu thudc vao tfnh chat cita vat lieu va thanh phan cap hat ban dau.
2. Tach nirdc tCr bun than cua cac nha may tuyen Hien nay, bun than cua cac nha may tuyen dugc tach nudc bang cac bien phap thdng thudng chfnh nhUsau (Bang 1).
Bang 1. So sanh cdng sua't va hieu sua't cua sang "ly tuang" va sang thdng thudng
Vat lieu Huyen phu cat thach anh Bijn than nha may tuyen than Bdt khd kim loai Cacbit vonfram Bdt Manhetit
Cao lanh, huyen phu (sy) can ca phe, cdng nghiep thuc pham
Cd ludi sang, mm
0,08 0,045 0,063 0,071 0,15 0,015
Sang thdng thudng C.suat, t/h.m^
8 0 0,03
- 3 0
Hieu sua't, % 60
- 50'
- 70"
-
Sang "ly tudng"
C.suat, fh.m^
45 60 3 3 10 3,5
Hieu sua't,%
90 80 95 96 93 98 Ghi chu: Theo chu ky phai lam sach ludi sang bang thCi cdng hoac phai rifa ludi sang.
Bang 2.
TT 1 2 3 4 5
Bun than pha "tdi han"
Cap hat, |im 45 55 100 150 355
T^ le cap hat<150 ^m, % 90
90 - - -
Ty le pha ran tmng binh, % 5
5 8 10 15
Cdng sua't, mVh.m^
25 30 60 90 170
Hieu sua'L % 88 88 90 92 92
• PhUdng phap ty nhien, phdi bun than tren bai
• PhUdng phap sang thdng thudng.
• PhUdng phap bang Igc ep.
• PhUdng phap ly tam.
• PhUdng phap sang "ly tudng" (Ultimate Dewaterer"^'^).
3. So sanh giCra cac phudng phap tren vdi may "tach nirdc ly tirong"
• Khdng ed gi de so sanh vdi phUdng phap ty nhien va sang thdng thudng .
•:• So sanh vdi bang Igc ep, myc do tach nude cua may "tach nude ly tudng" cd thap hon ddi chut.
Loai bun than cd hat ty 0+150 ^m, bang Igc ep cho ket qua do am trong bun than cdn lai la 20 %, sang
"tach nudc ly tudng" la 22 %.
Nhuge diem ci!ia bang Igc ep la lam viee gian doan. Chat lieu vao va thao lieu ra theo tyng me, sau mdi me deu phai ve sinh be mat Ige.
Cdng sua't thap, thudng xuyen phai thay bang Igc, chi phf cao. Thie't bi "tach nudc ly tudng" la may hoat ddng lien tuc khdng ngyng, chat lieu vao, tach nude va thao lieu ra ty ddng, khdng can sy trg giup eua thie't bj khac, cdng suat va hieu qua kinh te eao.
•:• So sanh vdi thiet bi Igc ly tam, thie't bi "tach nudc ly tudng" nd'i trdi hdn ca kinh te de'n ky thuat. Thung ly tam khdng tach dugc nudc ty bun than cd cap hat mjr^ 0+150 ^m; chi tach dugc nudc ty bun than cd hon hgp khoang cap hat nhd:
(Xem tiep trang 7)
CONG NGHIEP MO SO 6 - 2009
HOl NGHI KHOA HOC K? T H U A T MO TOAN QUOC LAN THUT XX
CNM
Nguyen ly eua may lang ly tam Kelsey sCr dung tat ea nhung thdng sd eCia may lang truyen thd'ng va eung vdi die'm bd' sung dac trung ed kha nang thay dd'i trudng trgng lyc bie'u kien tac dgng len cac hat rat min xuyen sud't ca ban lang. Trong khi b may lang truyen thd'ng ddng hgc la chuyen ddng rdi thing, thi trong may lang ly tam chuye'n ddng la xoay trdn.
Kha nang thay dd'i trgng trudng bieu kie'n, len de'n 50 lan trgng lyc, da lam tang hieu qua phan tach, dac biet dd'i vdi nhung hat khoang rat mjn bang viee giam dang ke' tac dgng eua nhung lyc gay can trd sy phan tach eua cac hat khoang min.
Viec tac cae chuyen ddng ly tam thye hien bang viec kie'm soat td'c do khae nhau cua rdtdr quay trdn. Phia trong cua rdto, sang sat hinh parabon quay dong true vdi rdto. Sang sat dugc phu mdt Idp vat lieu dem va ehung cung dugc rai ra bang lye ly tam. May bdm nap lieu vao bang dudng d'ng cd djnh dat d giua may va phii len toan bd Idp dem mam sang
Cac hat trong lieu nap se tang td'c ve phfa mam sang bdi tac ddng cua trgng lye bie'u kie'n, trong khi nang cao iien tuc Idp lieu dc sy djch chuye'n thing dyng eua lieu mdi nap vao.
Nhung hat cd trgng lugng rieng Idn hdn hay bang Idp vat lieu dem thi se lang xud'ng Idp dem.
Nhung hat di qua Idp dem thi se lang lai va tao thanh cae ddng nhd. NhUng hat khoang nang se di qua hoan toan Idp dem va rdi vao thung chya san pha'm quang. Nhung hat nhe hdn se khdng the lang xud'ng va duge da'y di d phfa tren Idp dem va rdi vad thung chiia quang dudi.
4.3. Ket qua tuyen cae hat mjn quang sat May lang ly tam Kelsey da dugc danh gia qua nhieu nam su" dung thye te la thie't bj tuye'n trgng lyc ly tudng ddi vdi eac hat quang sat mjn cap tha'p bdi kha na_ng tao dUde ty le lam giau quang eac trong khi v i n duy tri dugc myc thye thu eac.
Luu lugng lieu nap vao la 55 T/h va thu heach trung binh tinh quang la 5,5 T/h.
Ke't qua eho tha'y may lang ly tam Kelsey cd kha nang thu dugc tinh quang sat vdi ham lugng sat cao ty ddng lieu cd chat lugng rat tha'p va mdi chi dugc giai phdng mdt phan quang. Ddi vdi phan quang mjn thi ke't qua rat rd rang.
5. Ke't luan, kien nghj
• Nen thye hien tuyen rieng re 2 loai quang manhetit va oxi hoa, se dem lai nhieu uu viet ve hieu sua't tuye'n, chat lugng tinh quang, myc thye thu...
•:• Nen tang ty le san pha'm tinh quang ve vien bdi nhieu tfnh Uu viet ve cd, ly tfnh va gdc do mdi
trudng khi sCr dung trong luyen thep. Quang ve vien cung se la san pha'm thUdng mai de tieu thu.
•:• Nen thye hien bd' sung eac thf nghiem cd SLf dung may tuye'n ty xung va may lang ly tam Kelsey Model J1800 trong day chuyen tuye'n quang sat Thach Khe de cd the tim dugc quy trinh tuyen td'i Uu eho quang sat Thach Khe.d
Ngudi bien tap: Tran Van Trach
mui\i*m%yn^\i^m»l^ii
M
. _, ppses the selection of the japer concentration technology for Thach
\e iron ore mine under the aspects of the iparate concentration for magnetite ore and [idized ore and the increase of the pellet joportion. it also proposes the pilot
;i|ization of rnagnetic concentrators and
||sey centrifugal separator for Thach Khe )n ore concentration line.
SANG PHAN LOAI THAN...
(Tiep theo trang 3)
cap hat Idn (de'n 500 ^m) la 35 %: 65 %. CJ Nam Phi thung ly tam (solid bowl centrifuge) ed gia ty 500.000 de'n 700.000 USD/may. Chi phf van hanh khoang 0,35 USD/tan than tach nudc.
Thie't bj "tach nudc ly tudng" la mdt may rung binh thudng, gia re, ddn gia van hanh chi khoang 0,006 USD/tan bun than tach nude, nghTa la re hdn gap 60 lan ddn gia van hanh thung ly tam.
Vdi loai bun than, may ly tam khdng the tach dugc nude, thi may "tach nudc ly tudng" cd the tach dugc nudc de'n dg a'm cdn lai trong bun than la 22 %. Bun than cap hat cang Idn, thi chi sc tach nude eua may "ly tudng" eang tang va dg a'm edn lai trong bun than se giam de'n 8 %, 7 % va thap hdn.O
Ngudi bien tap: Nghiem Gia
IMMARY
Introduces the high frequency proper equipment for classifying fine e coal and dewatering coal slime.
CONG NGHIEP MO SO 6 - 2009