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HOl NGHj KHOA HOC Kf I H O A l MO TOAN QUOC LAN THIJf XXKHAI THAC THAN HAM LO D U d l DOI TUONG CHUA
TS. NGUYEN VAN CHI, KS. N G U Y I N H Q U HUAN KS. T R A N T U A N ANH - Vien Khoa hgc Cdng nghe Mo-TKV
1. Khai thac khoang san ran dudi cac doi tu'dng chura nudc tren the gidi
TO lau, nhieu nude tren the gidi tap trung khai thac tai nguyen nam dudi day bien trong vung lanh hai rdng 12 hai ly va trong vung tiip giap lanh hai rdng 200 hai ly theo Luat Bien dupc Lien hiep qud'c thdng qua nam 1982. Viec khai thac khoang san ran dudi cac dd'i tupng chya node nho bien, sdng, ho... ddi khi gay ra eae sy ed nghiem trpng.
Tai Hungary khi khai thac md than, md bauxite b Dadunaiskiy da bj buc nude dan tdi,ngap Id va mo hoan toan do node eastd trong dat da vach ky Triat va Paleoxen ehay vao. Oe khae phue ngudi ta da phai xay dyng cac tudng chin nudc nhan tao va de lai tru bao ve.
Tai Anh nam 1837 da khai thae than d i n dp sau 45 m each day bien, be day Idp soi va eat tren vach Id la 27 m, be day da cyng vUng khdng qua 18 m.
Khi khai thae da xay ra buc node md chit ngudi.
Khai thae than b Levantskiy dudi day bien each bd hdn 2130 m, b dp sau dudi day bien 40 m cung da xay ra buc nudc.
Tai Canada mo than Sidnhei khai thae 11 via than day tO 0.75 d i n 2.5 m dd'c 6 den 40° dudi day bien ty 183 d i n 700 m (trung binh 500 m) cd vach la da phien y i u , da phiin set chat bang he thd'ng buong cdt va Id lien tue. Tai Vaneuver khai thac 2 via than dudi day bien day 0.6-3 va 0,9-1,2, each nhau 15 m. Via tren khai thac bang he thd'ng budng cdt (de lai 70 % tru lopng). Via dodi dope khai thae theo he thd'ng khai thac lien gOdng, va khoang khdng da khai thae dope chen bang dat da. Tai Chile da khai thae than da Neogen xen kep giOa cac ting set da phien set, da phien mica va da vdi.
Cac via than d day day 0,63 m, 1,2 m, 1,5 m, 1,24 m nam each nhau ty 12 tdi 18 m, dd'c nghieng 20°
v i phfa bien. Tai oyc b luu vyc sdng Reinsko- Vestphalskiy (Rurskiy) da khai thac via than the nam thoai, day 2 m, d dp sau 60 m cua ben dudi ho chya nude dung tfch 250 nghin m l Mo mudi kali day 30 m dope khai thae bang he thd'ng ham Id b
dp sau 90 lan be day via vi tang phCi cd Idp set day 10 m. Tai Bi khai thae than da d lou vyc sdng phia Bac phfa dodi Idp phCi De tO da xay ra ngap mo than. Dodi ap suit eCia nudc dat da b gUdng Id khai thac va Id chuan bj bi pha vd thudng xay ra ngay ca khi nude ehay vao mo khoang 4-5 m^/gid. Tai Phan Lan da khai thae mc ddng- pirit Outokumpu, san lupng 170 nghin tan quang/nam nlm dudi ho nudc bang phUdng phap him Id. Cac Id dupe chen lap bang be tdng...Nhat Ban la nude cd nhiiu kinh nghiem nha't v i khai thac than dudi day biin.
2. Khai thac than dudi cac doi tUdng chura nudc 6 Viet Nani
Hien tai, trO lupng than cd the khai thae lo thien cCia Viet Nam dang can kiet. De ed dCi than cho n i n kinh te. Tap doan TKV dang thiit k i xay dyng nhiiu md than ham Id mdi, khai thac xud'ng sau tdi -450 b Ha L i m , tdi -475 b Nui Beo, tdi - 700 m b Khe Cham II va IV... cd mo se khai thac dodi moong Id thien... Viee khai thac than dodi day eae ho node, ddng sud'i dang dupe xem xet (Bang 1). Khi tai nguyen than can kiet, se phai khai thac than dudi day biin d K i Bao, vjnh Cud'c Be, Bach Long VT...
Bang 1. TrU lugng than Quang Ninh tdi -300 nam dudi mdt s6 hd chUa nudc.
Khu vyc cam khai thac Cac ho Bae Odng Trieu Cac ho Odng Odng Trieu Yen Lap - Odng Ho
Ho Cao Van Khu Dien Vpng
Ben dudi dd'i tupng chaa node Ho Ninh Son, Ben Trau, Khe Che, Trai Ldc
Ho Cau Cud'n, Ndi Hoang, Khe LTdm, Yen Dudng, Tan Yen Hd Yen Lap, ho Oong Ho va rCfng dau nguon
Ho va dap Cao Van Ho, dap va nha may nude Ghi chii: TrU lugng than tdi mUc -300 bang 119.568.000 tan.
CONG NGHIEP MO SO 5 - 2009
HOI NGHI KHOA HOC KY THUAT MO
T O A NQUOC LAN THUf XX CNM
Hien nay, tai vai md da ed nhang thdi gian, phai khai dao ham id dodi dd'i topng chOa nude: Vf du 1:
b md Ble Cpc Sau dang khai dao dudi day bai thai chya gan nCfa ty m^ da thai. DUdi day bai thai ed ddng sud'i chay v i phfa Bac vdi 5 phu lUu, nay bj da thai lip kfn nhung ed lupng nudc ehay ra Idn hdn 20 lan lopng node chay vao 2 tang Id +17 va -100 cua mo Ble Cpe Sau. TO 16 Id khoan tham dd da ve dope dien phan bd node nglm trong Idng bai thai b cot eao +50 cd dien phan bd node ngam ldn nhat dat tdi 1,5 km^ trong mua mUa. Tdi cud'i nam 2008, cac dudng Id tO phia Tay Bac bit d i u dao vao dudi vung phan bd nude ngam. Day cd the coi la khai thae dudi dd'i tupng chya nude nglm.
Tai Vang Danh ed Id chp 11-8-2 dang khai thac phia dudi Idng sudi Tay Vang Danh-2 cd 2 doan di dudi ddng sud'i chay ty Bic xud'ng Nam. Khi Id chp 8-11-2 pha sap da vach thi Idng sudi TVD-2 nam
ngay trong vung sut lun nut ne va nudc sud'i trong mua mua da ehay vao Id gay trd ngai cho san xua't.
Tai Mao Khe, mua mua 2008 ed hdn 20 Id via eu, mdi dang chya nudc. Phfa dudi eac Id dang chya node hay da thai...diu cd h i m Id.
Cae Id chp phfa dadi sau khi pha hoa toan p h i n tao ra vung sut lun ed cae khe nCrt dan node lan tdi dja hinh, khe, sudi, bai thai, day Id via... Vao thang 7, 8, 9 hang nam ed lupng mUa rat Idn va cac Id via, moong Id thien, khe can, ldng sudi, bai thai... chaa day nude se lien thdng thuy lyc tdi h i m Id dudi sau thdng qua cae khe nCft sap dd tren ndc cae Id chp. Day la thdi doan h i m Id khai dao "dodi cac ddi tupng chaa node". Trong thdi doan mOa n h i i u , keo dai nay, b nhUng mo cd ty le % da chOa node cac 70-80 % nhO Khe Cham 2 da nhiiu I l n xay ra ngap Id tO node mOa ngam xudng!
Bang 2. Mdt s6 glal phap, bien phap phdng chdng nudc mo him Id [1].
Thao khd md ham Id
Giaiphap
Ha thap myc nude ngam (trade hay trong
qua trinh khai dao)
Cae cdng trinh di trade phdng ngya
1 Thoat node
Phdng tranh node tham xud'ng
Id
Gom va thoat node ty chay Bdm thoat node
Khoan thao nudc
Pham vi ap dung Ty be mat dia hinh
TO trong Id
Ty trong Id
Ty tren mat da't
Ty trong ham Id
Thoat node ty chay tren dja hinh Thoat nudc ty chay trong Id bang
Bdm node ty be chaa b mdi tang len be mat dia hinh Bdm thoat nudc cae doan Id
ngap cue bd Cdng trinh khai thac cu Ddn vi chya nUdc tu nhien
Bien phap
Khcan thing dOng l i p bdm chim Khoan ngang thoat to chay
Ong lpc ddng Ong loc xuyen Hd ha thap mUc node Ld khoan ha mOc node
Ld ngang tieu nudc Hoc danh sap Khoan tien trudc gOdng
Ld tham dd di trade Cac tadng chan Xay dap ngan node:
Bdm ep phut lap gia cudng Di ddi vat the nude Bit lap khe nirt be mat Chon vi trf eCfa Id tranh node
Chen la'p sau khau than Oe lai tru than bao ve
Trinh to khai dao
Ranh thoat node be mat dia hinh Ranh thoat node trong Id
Lya chpn may bdm , Lou lUdng th dat node td'i da
Ham chOa node trong Id Dodng d'ng bdm thoat node
Day Id via, day bai thai Ldng sud'i ngam. ddi hu9 hoai
TT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 3. Giai phap phong chong nudc cho mo than
ham 16
Tren t h i gidi de phdng chdng nudc buc ehay vao
him Id d i u tien eln dy tfnh chiiu cao phat trien vung khe nurt dan nudc tren ndc Id chp pha sap da vach... de xac djnh dp sau khai thac an toan. Ngay ea khi da d i lai Idp da't da phu ben tren ham Id,
CONG NGHIEP MO SO 5 - 2009
HOI NGHj KHOA HOC KY THUAT MO TOAN QUOC LAN THUf XX
trong mdt so trudng hpp nude v l n buc, chay vao ham Id ngoai dy tfnh. Khi dd ngudi ta chpn ap dung mpt sd giai phap (xem Bang 2):
Thao kho tir be mat dja hinh: ed hieu qua khi tang chya node ed he so tham K>5 m/ngay...
Khoan thing dyng lap bdm chim ha tha'p mUe nude (H.1) cd the thao khd tdi 75 % lOpng node ngam ed the chay vao md: 1 - Khoan nhiiu LK thing dOng xung quanh Id lap bdm chim; 2 - Ld eln thac khd (giam ap lye); 3 - Pheu ha thap mye node ngam khi khoan 1 Id lap bdm.
thoat vao Id ngang cd the tdi 60^100 m%...
C l u true Id (Id khoan) ngang tieu node md ta tren H.2.
v:^y/..y'///,X^y^///AY.</.^Y/.
1 2
H. 1. Thao khd tU be mat dia hinh.
Thao khd tU trong Id cd the dung d'ng Ipc ddng kim loai dodng kfnh (t)=25H-63 mm, khoan nhiiu Id nho dng Ipc lo khoan (lo trdn 0=20 mm, lo cho nhat 20x5 mm) cd d i u nhpn cam vao ndc, hdng, gOdng, n i n Id sau <12+15 m.
Oudng kfnh Idn hdn 63mm chi lam tang them nguy cd buc nudc, da't chay ma luu lopng node tang khdng dang ke. Tdng dien tfch cae lo due chiem 5^7 % dien tfch b i mat d'ng Ipc cam. Thdi gian lam viec 5^12 thang. Ban kfnh anh hodng khdng qua 20^-25 m: Sd dd lap d'ng Ipc ddng thao node Id dpc via.
Ong Ipc xuyen dung trong cac md dao trong eat, da vdi, dd Id mft cd dp dan riudc eao, giup phat hien tang sung node each than Id mdt Idp da each node mdng, ha tha'p rat hieu qua mye nudc khdng ap, giam ap lyc b vach tru Id. Oau tien khoan md Id bang khoan tay, mui khoan thia, rudt ga nhd cd chiec kep sat va ddn xoay tdi each Idp chya nude 20-r30 em thi dyng
khoan, an vao bang kfeh thu^ lyc.
Lo khoan (hd) ha tha'p muc nudc khoan ndng 0>152 mm hay dao vao n i n Id sau =s3 m dat bdm hut nudc lien tuc. Cac lo khoan (hd) each nhau 10^30 m lam giam nhanh ap loe len day lo khoan ha thap myc node n i n Id.
Ld (Id khoan) ngang tieu nudc dao xuyen vao tang da sung node vdi (t)=1,5^2,0 m cd the tao ra p h l u ha tha'p cd (J)=500-800 m. Lopng nude
H.2. Ld khoan ngang tieu nudc: m - Chieu day tang chUa nudc; D - Dudng kinh Id khoan; X - Khoang each tuang duang vdi ehiiu cao H^ dudng dang ap
• each Id khoan.
Khoan tie'n trudc vao gOPng Id, ndc va hdng tham dd "tui" nude ngam ed the buc vao Id.
Dao Id tham dd di trudc cd t i i t dien khoang 4m^, chdng gd l i i n vi, dao b dp cao 5-7m ben tren t i n g chaa node, ben dodi tang chOa nudc 15-20 m... de khoan vao tang chya nudc... Oao Id tham dd tiet dien 4 m^ ehd'ng go lien vi vao vung cd nguy ed buc node cao b Id -80 Mao Khe nam 1996.
Xay tudng chin nudc Viee thi cdng cac tOdng chan node nay dugc lam rat nhiiu b tang Id -50 md Ha Lam. Dau tu cho cac tudng chin khdng qua Idn nhung khi buc node, giam thieu dope nhiiu mac dp thiet hai nhu can node ehay vao ngap md td bdm, can bun trdi lap toan bd dudng Id... Tudng chan node xay bang gaeh ed cCfa thep ddng md xay tai Id van chuyen -50 Ha Lim.
Dap ngan nudc ddng bang cay gd ngan buc node xud'ng: xep go chdng Id dudng kfnh khoang 15cm va chieu dai khoang 1,8m song song vdi dudng Id, nhof la cay hoac rdm ra vao khe hd giua cae cay gd vdi nen da va ddng dinh co djnh eae cay go vdi nhau. Phia dudi chan dap nhet d'ng thoat node vao, phfa tren dat ddng ho do ap lye node, khf...
Bam phut ep gia cudng, bjt lap tai Lien Xd eu theo tieu chuan (Snhip 111-11-77) khi nude ehay vao gUdng Id dy kie'n Idn hdn 0,0022 m^/s (7,92 m^lh) e l n t i i n hanh phut ep trade khi dao Id.
Phut ep dung djch xi mang (set, bi tum...) vao dat da md thay ddi k i t ca'u tang them dp cOng va bjt kfn eac khe ndi d i n node (H.3).
Di ddi vat the nudc: la di chuyen ddng ehay thudng xuyen, khd'i nude mat Idn tren be mat khai trudng.
CONG NGHIEP MO SO 5 - 2009
HOI NGHI KHOA HOC KY THUAT MO TOAN QUOC LAN THIJf XX
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Bit lap khe nirt be mat: la hieu qua nhat trong vipc ngan chan node mOa, node mat ngam chay xudng Id qua vung sut lun, nCrt ne sau khi pha hoa toan p h i n khdng chen Id.
Chgn vj tn cda Id sao cho trong mpi trodng hpp node moa, bac, lu, thuy trieu d i u khdng the ehay tO ben ngoai qua cCfa Id vao.
Chong nudc tha'm tUId mUc tren bang chen Id.
\.
H.3. Khoan phut ep gia cudng bjt lap: 1 - Ld khoan phut ep vda xi mang; 2 - Dudng Id bj nudc chay vao
qua nhieu.
A A A A A A A A A A , . A A A
H.4. Khai thac khdng chen Id.
Neu khdng chen Id thi Idp da each nude (a) sau khi sut lun, bj pha hu^, tao ra khe nCrt de nude ngam ty tang (a) chay xud'ng tang (b) roi chay vao Id chp. Neu chen Id vdi b i day (v) thi Idp dat da each nude (a) du lun sut nhung choa tao ra khe nCft de node t i n g (c) ehay qua.
De lai tru than bao ve: Tru than bao ve ngan node nglm tO Id khai thae Idp tren xud'ng Id Idp dodi (H.6).
H.6. De lai tru than bao ve.
Bam thoat nudc md eln dope ty ddng hoa vdi d l y dCi cac chye nang cua tram bdm ty ddng.
Khoan thao nudc cdng trinh khai thac cu khi tiep can tdi g i n tdi khu vyc cd khai thae eu b khoang each dudi 50 m.
4. Ket luan va kien nghj
Khi khai thac than ham Id dudi ddi tupng chOa nudc can tham khao ap dung 27 bien phap phdng ehd'ng node tdng hpp trong Bang 2.n
Ngu&i bien tap: Ninh Quang Thanh
:;' ' ' 'SUMMARY*"''' i
I $ o l i d mineral mining activities under I the water bearing objects has been
carried out in mahy cbuntHes on the world and in V i e t n a m as w e l l . The paper i represents preventive solutions pf water
activities under the water bearing objects with underground mining method in the u n d e r g r o u n d mines of Quang Ninh coal basin.
H.5. Khai thae cd chen Id.
CONG NGHIEP MO SO 5 - 2009
