Thong tin khoa hoc cong nghe mo
GlOn THIEU MOT SO HE THONG KHAI THAC, CONG NGHE KHAI THAC AP DUNG TRONG KHAI THAC QUANG HAM LO
TS. DAO DANH PHUgNG
Vl§n Khoa hgc Cdng ngh^ Md-Vinacomin
Biin djch tw tdi liiu: "Mdt sd phwang dn md vfa, chuin bi rugng md vd khai thac qudng bdng phwang phdp him Id", bdn tiing Nga, NXB Nhedra-Matxcava 1972 1. He thong khai thac kha'u duoi thac buIng - cpt (Thdng tin KHCN md da gidi Ban chat vadieu kidnap dyng thipu d s l 11/2011).
Hp thing khai thde khlu dull Id hp thing P'®"^ "^^^^e bipt^cua hp thing khai thde khlu khai thde vdi khoang khong gian khai thde md, ^ " ° ' ®° ^°'' ^^ \^°"9 ^^^^ ^^^^ ^^°^3 - cot. Id trong dd than qugng 6wgc khai thde blng P^^i trung^ehuyen quang da khai thde ra den guang khlu dull, chlng giu khoang khdng ^^c vj tri boc xep trong khoang khdng gian khau, gian khai thde blng ede tru bao vp Id qugng ^o"' "^leu each thiic chuyen qudng khde nhau, hodc dd (trudng hgp trong than qugng ed dd). ^^^ ^^^^^ y^o the nam eua than qudng vd theo Trudng hgp than qugng ed chilu ddy khdng ^ ° '^ ^o- do bo tn eae duang lo ehuan b;:
Idn (Im 2m), thay vi d l Igi trg bao vp, cd t h i - Trudng hgp than qudng n i m ngang vd rit xIp da thai 6k 6a ndc, hoge xdy dyng cde trg thoai, gdc die d i n 2°30', khi trg phang thi bao vp nhdn tgo. qudng 6wgc chuyen ehd bang godng vd tdu Trong he thing khai thde ndy, ngudi ta <^'^" ^1° tryc tilp t i i guang khlu d i n vj tri khdng chia ting hoae rudng md thdnh ede bile, "^^S ^^^ S'eng. Truang hgp trg khong bang md thye hipn khai thde blng guang khlu dull, P'^^ng thi chuyen sang ma lo vgn tai trong da.
clt tii ede dudng Id chuin bj. Dien tich eua Jrong nhilu trudng hgp, hgp ly han ea cd guang khlu chinh blng dipn tich dudng bien the dp dgng van tai khong dudng ray d i n cong nghipp eua than qudng vd se tgo nen gilng hoge d i n xudng sdng tuyln, khi md vfa khoang khdng gian da khai thde rdng Idn. khodng sdng bang Id bang hoge 16 nghieng.
He thing khai thde khlu dull thudng 6wgc ^ Trong tm-dng hgp than qugng nim thoai, gde dp dgng trong cdc dilu kipn dd vdy quanh vd die tii 2°30' din 6°10'. cd t h i sii dgng hinh thiie qudng eiing, b i n viing, than qudng nam ngang, vgn tai bang tdu dipn keo cdc toa tm-c tilp tii thoai vd nghieng vdi chilu ddy 5 - 7m vd thich gu'ong Id, hodc sii dung he thing van tai khong hgp khi trong than qugng c6 cde khu vyc (du'dng ray, hoge tdi cdo tii Id thdo qugng din Id qudng ngheo, da xam nhdp, 6k lgi Idm tru bao vgn chuyin ehinh md trong dd md.
vp thay t h i cho ede tru qugng, nham giam t i n Trudng hgp than qudng thoai d i n nghieng, thit tdi nguyen. gde d i e tii 6-10° d i n 18°, trong dilu kien nhu
Trong hp thing khai thde khlu dull, t i n thit vgy dgng ble xIp ehinh Id tdi cdo, cdo vdo quang chilm 10% vd Idn han, vi vgy, mgc du pheu rdt qugng hoge vdo godng dat^d cde quy trinh cong nghp khlu dan gian, gia thdnh c^u-dng Id vgn tai qugng,^ cung cd the bang khai thde quang thip, tuy nhien chf nen dp bdng tai nhieu cdp vdi boc xep qudng trong dgng khai thac cdc khoang sdng cd qugng gis gu-o-ng bdng tdi cdo.
trj khong cao, hoge cdc khu vyc khdc dp dgng Trudng hgp than qugng nim nghieng, vdi cdc hp thing khai thde khdc. Trong cdc trudng gdc die Idn han 18°, thudng su dgng cao tdi hgp chilu ddy than qugng Idn han 7m, nam Id p h i biln nhlt d l trung chuyin yd da tai, cd ngang hoac khi chilu day than qugng Idn han t h i d l vdo phlu rdt qugng, hoac do vdo godng, 5m, nim nghieng thi he thing khai thde khlu dgt d cde dudng Id van tai qudng d l tilp tgc van dgli giam hipu qua, d n chuyen sang dp dgng chuyin din cdc thugng, dua qugng di len hoge cac he thing khai thac khdc nhu hp thing khai xuIng dudi.
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NhQ'ng phuxyng an cong nghp co' bin Phg thupc vdo gdc d i e cua khodng sdng trong hp thing khlu dull ed cde cdng nghp khai thde, vdi khlu khdng chia ting hodc chia ting, trong dd khlu khdng chia ting dp dgng khi khai thde cdc khoang sdng ndm ngang hoge rit thoai (a < 6-10°), edn khai thde chia ting khi gdc d i e vfa tuang d i i Idn.
Tuang iing vdi ede dilu kipn tren, trong hp thing khai thac khlu dull ed hai sa d l cdng nghp khai thde ea ban, dd Id khlu khdng chia ting vd chia ting.
Dac diem ky thu$t, kinh ti cua hp thong Hp t h i ng khai thde nay eho c6ng suit khai thde ldn vdi khlu dipn rpng, khii lugng cdng tdc chuin bj khdng Idn, chf khoang 1-2m/1000 t i n qugng vd thugn Igi trong vipe dp dgng ea gidi hda ding bp cdc cdng dogn san xult, tii khdu tdch phd qugng d guang, ble x I p vd chuyin tai qugng. Khi dp dung ea gidi hda ede cdng dogn khai thde, sii dung mdy xue, dtd ty d l , may ble xue vdi godng ty hdnh se eho ndng suit lao dpng tuang doi cao vd hg gid thdnh khai thde qudng.
T i n thit qugng trong qud trinh khlu la khong ddng k l , ehu ylu Id do 6k Igi trg bao vp, ty lp t i n thit din 10-15% hoge Idn han.
Miie dp Idm ban qudng khdng Idn, ban nu'a do khai thde ehpn Ipe, phan logi qugng tgi guang nen ed t h i kilm sodt vd giam thilu 6wgc chf tieu nay.
Hp thing nay cho ndng suit lao dpng cao, tnj-dng hgp chilu ddy than qugng khdng Idn (2- 3m), ndng suit cua thg khoan dgt 8-1 Om^ vd vdi chilu ddy thdn qugng 7-8m, ndng suit thg khoan dgt din 20-30m^ hoge eao han nua. Nang suit eua cong nhdn trong guang khlu dao dpng tii 2 din 6m^ hoge Idn han, phg thupc vdo miie dp ea gidi hda cdc cdng dogn khlu guang.
Chi phi thulc n l dao dpng trong khoang 1-1,5kg/m^ phg thgpc vdo dp ciing cua qu$ng vd chilu ddy cua khodng sdng. Chi phi vgt lipu chlng Id Id thip nhlt so vdi cac hp thing khai thde, tuy nhien, d n cd bipn phap kilm scat trgng thai vdch 6k dam bao an toan.
Tuy nhien, hp thing khai thac khlu dull cung cd cde nhugc dilm, dd Id t i n thit qugng v l n cdn Idn, miic dp an todn khdng cao, nhlt
Id khi khai thac ede than qugng cd chilu day Idn, cdng tdc gidm sat trgng thai vdch khd khan.
2. Cong nghe khai thac vdi khau chia t i n g , trong he thong khai thac khau duoi
Trong cdng nghp ndy tiln hdnh khlu chia ting, guang khlu d u l l chuyin djch theo phuang via (hinh 1), theo t i l n dp khlu, 6k lgi cdc trg bdo vp. Trong hinh 1, O.C Id gilng ehinh eua md, " U," Id cdc trg bao vp, ede mui ten chf hudng chuyin djch cua guang khlu.
Tmng chuyin qudng thudng sii dgng cdo tdi trong cdc tnfdng hgp gdc die cua than qugng khdng Idn, chilu cao nghieng cua ting khai thde din Id vgn tai eua ting trong khoang 60-100m, toj-dng hgp xa han, chuyin tai qugng bang godng.
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Hinh 1. Cdng ngh^ khai thde khiu duoi, chia tang Cong tac chuan bj
Cdc t i n g cd chilu eao diing g i n 30m, 6wgc chuin bj blng cdc dudng Id vgn tai (LLIo) vd thugng thdo nghieng. Trudng hgp khlu mpt chilu thi trong t i n g md mpt 16 thugng, trudng hgp khlu ra hai cdnh, tuang iing m l i cdnh md mpt 16 thugng, tgo 16 c l t hinh thdnh cde guang khlu. Dpc theo 16 vgn tai t i n g d l Igi cdc tru bao vp, ding thdi md cac 16 n i i "C" 6k chuyin qudng tdi cdc dudng 16 vgn tai vd d i i dipn vdi ede 16 n i i nay md khdm "H" dgt trgm tdi eao.
Cong tic khau qu$ng
Hinh 1 cho thly hudng phdt triln guang khlu duli, guang k h l u djch chuyin theo phuang, trong mpt s l trudng hgp chan ting cd t h i khlu vugt trudc 6e thugn Igi cho eao tdi Idm vipe.
Qugng khai thac dugc chuyen ra Id van tai t i n g qua Id n i i C, cd ciia d l x I p tai qugng true t i l p vao godng. Cao tdi "CJl" chuyen vao kham H. Khi chilu day than qugng nhd, viec van chuyin qugng cd the tiln hdnh dpc chilu ddi
KHCNM s d 2/2012* TAI Ll£U VA THdNG TIN NUdC NGOAI
Thong tin khoa hoc cong nghe mo
cua dudng Id. Trong trudng hgp ndy ed t h i sii dgng trgm cao tdi di dpng, chuyin djch tren dudng ray d l keo godng.
Khlu qugng vd chlng giu khoang khdng gian da khai thde tuang t y nhu cdng nghp khai thae khlu khong chia t i n g trong hp thing khai thde khlu duli.
3. Cong nghe khai thac khau khong chia tang trong he thong khai thac khau duoi
Cdng nghe khai thde khlu khdng chia tang Id mpt trong hai sa do cdng nghp ehinh trong hp thing khai thde khlu duli, dp dung khai thde qugng blng phuang phdp h i m Id.
Khi dp dung khai thae qugng blng cong nghp khai thde khlu khong chia tang, sau khi md ede dudng Id vgn tai n i i vdi gilng ehinh vd gilng phu, guang khlu duli (hoge Id mpt logt guang khlu) dugc thilt Igp, d t t i i dudng Id van tai ehinh, eung vdi qud trinh khlu se d l l^gi trong khong gian khai thde ede trg bao ye can thilt. Trong cdng nghe ndy ed t h i ble xIp qudng khai thde vdo godng, dua tryc tilp vdo guang khlu.
Trong cdng nghe khai thde nay, chilu cao cua khoang khong gian khai thde phg thupc vao chilu ddy thdn qugng, cdn kieh thude eua cde khu vyc khlu theo mat phang nam ngang phg thude vdo miie dp b i n vung eua dd vdch vd qudng, cung nhu vdo ede kieh thudc eua khodng sdng.
Cong tac chuan bj:
Sa d l ehuan bj rupng md dugc ehpn phu thupc ehu y l u vdo dae dilm cua trg, can eii vdo dd cd t h i md Id chuin bj trong qudng hodc trong dd.
Trudng hgp p h i biln nhlt Id trg khong blng phang, trong trudng hgp khi dd xam nhdp sau vdo than qugng, hoge dgng cdi rdng luge giu'a qugng vd dd md, cung nhu khi ed ede dut gay kiln tgo, viec b l tri Id chuan ^bj trong quang r i t khd khan, tham chi trong nhieu trudng hgp khong t h i thyc hipn duge^ vi vgy phai dp dgng phuang an b l tri Id chuin bj di trong da.
Theo phuang an nay, cdc dudng Id chuin bj b l tri trong da trg, dudi than qugng, vi bo tri nhu vgy se khai thde dugc tript d l khoang san trong than quang, ding thdi tgo thugn Igi trong
vipe thdo qugng, chuyin qudng tii guang d i n phuang tipn vgn tai tren Id van tai, ngodi ra cung phai k l d i n thugn Igi khi tgn thu quang trong ede tru bao vp.
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Hinh 1. Cdng nghe khai thde khau khdng chia tang, trong h? ihong khai thde khiu duoi Chuin bj khodng sang qugng duge md^ta d hinh 1, trong dd gilng nang qudng (OC) noi vdi dudng Id vgn tai ehinh (LUo), vdi gilng phu (BC). Dudng ke diit quang, ke dpe theo dudng van tai ehinh Id chf gidi eua tru bao ve 6k lai bao vp dudng Id trong thdi gian khai thde. Trg bao vp ndy 6wgc c l t bdi cdc Id nii, n i i dudng Id vdi khoang khdng gian khai thde d l thong gi6, chuyin qugng vd ngudi di Igi.
Cdng tdc khai thde duge tiln hdnh theo hudng tii gilng ndng qugng (O.C) d i n gilng thdng gi6 (BC). Khi chilu ddy thdn qugng khdng Idn, thong gi6 eua guang khai thde e6 t h i blng khuleh tdn, guang khlu duge hinh thdnh t i i m l i 16 n i i eua khoang khong gian khlu vdi dudng Id van tai. Khi ehieu ddy eua thdn qugng ddng k l md, ede dudng Id van tai c l t ngang (LU) d i n bien gidi eua than qudng vd t i i dd md ede Id d t (LUp). Cde dudng 16 ndy viia Id 16 thong gi6 vd Id i l i thodt thii hai t i i kh6ng gian khlu.
Cong tac khau quang
Phg thupc vdo kieh thude eua rupng md, trudng hgp rupng md ed kieh thude nho, cdng tdc khlu bat d i u tryc tilp tu cdc Id nii trong trg bao vp g i n dudng Id van tai, cdn khi rupng md CO kich thude Idn thi bat dau khlu tu dudng Id clt. Than quang cd chilu day d i n 3m thyc hipn khlu guang duoi, khdng chia bgc, tuy nhien, n l u cd eac thilt bj phij hgp chilu cao nay cd t h i tang len 4m. Tdch phd qugng blng no min, vdi Id khoan sau 2 2,5m vd Idn han, su dgng khoan tay cd gid da.
KHCNM s d 2/2012* TAI LIEU VA THdNG TIN NUdC NGOAl
Trudng hgp khai thde cdc thdn qudng cd chilu day tren 4m, khdng chia bdc khlu, nhung phai b l tri Id tiln trudc d vdch. Id cd kieh thude chilu cao khoang 2m, chilu rpng khdng ldn han khoang each giiia ede trg bdo vp. Trong qud trinh khai thde gu-ang Id tiln trudc luon duy tri vugt trudc bgc khlu khoang 4m. Dk tdch phd qudng trong bgc, cd t h i dp dung phuang phdp khoan-nl min blng l l khoan diing hoge 16 khoan nghieng, cdn d i i vdi Idp qugng d tru, tdch phd qugng blng nhu-ng l l khoan n i n (hinh 2).
Trudng hgp tdch phd qudng blng l l khoan nhd vd chilu ddy than qudng 6-7m, d n phai chia thdnh hai hodc nhilu bdc khlu han, trudng hgp tdch phd qugng bdng l l khoan diing ed t h i chf vdi mpt bgc khlu. Khi ehi ed mpt bgc khlu, qudng khai thde ra 6k tryc tilp d guang, edn khi chia nhilu bgc khlu thi qudng dugc xue, chuyin t i i tren xuIng, tii Id tiln trudc xuIng Iln lugt tiing bgc, d i n bgc dudi cung.
Dk tang ndng suit khlu guang, d n thilt phai trang bj thilt bj khoan, nhlt Id cdc mdy khoan ty hdnh ndng suit cao, vdi t l hgp hai ddn khoan cdng suit Idn, logi khoan bua chen, sii dgng luon h i trg ngp min.
Qudng khlu d guang dugc dua d i n phlu rdt qugng, tuy thupc vdo phuang phdp chuin bj (trong dd hoge trong qugng), cung nhu gdc die eua thdn qugng, qugng dugc dua d i n phlu rdt qugng g i n nhlt blng tdi cdo hoge chit tai vdo godng.
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Hinh 2. Bo tri lo khoan tdch phd qu$ng trong b$c khiu
Khi sii dgng cdo tdi, n l u cdc trg bao v$
trong khoang khdng gian da khai thde gdy khd khan cho tdi cdo Idm vipe thi cd t h i s i i dgng cdo tdi ba tang trlng.
D l thay t h i cao tdi, nhilu nai ngudi ta s i i dgng mdy x I p tai chuyin dpng blng xich hoge bang khi nen, k i t hgp vdi godng t y hanh
(khdng cd dudng ray) da tang nang suit ble xIp qudng mpt cdch ddng k l , tdng ndng suit lao ding, dan gian hda day chuyin vdn tai vd hg gid thdnh khai thde qugng, nhlt Id d i i vdi ede thdn qudng ndm ngang, d i e 2,5°- 3°, hoac cdc trudng hgp vgn tai blng dudng s i t gap khd khdn.
Godng ty hdnh chuyin qugng t i i guang khlu d i n trgm b l e x I p d dudng Id vgn tai chinh, t i i dd vgn tai blng tau dipn 6k chuyin qudng d i n gilng ndng (cae md s i t cua bang Alabama, My) hodc chuyin tryc tilp blng godng ty hdnh d i n gilng ndng, thdm chi khi md via bdng Id blng hodc blng gilng diing cd t h i chuyin thing d i n nhd sdng.
Anh hudng Idn d i n nang suit b l e xIp eua mdy x I p tai ehinh Id dp cgc cua qugng. Ndng suit b l e x I p se giam theo kieh ed tang len eua dp cgc, cdn b l e x I p blng tdi cdo, ndng suit khdng bj anh hudng nhilu. Vi vdy, n l u sii dung mdy b l e xIp, cdng tdc khoan - n l min trong guang k h l u phai tinh todn sao eho dam bao dgp nhd qugng t i i da. Trong trudng hgp nay, ehi phi khoan n l se tang len, tuy nhien, can d i i chung trong chi phi khau khoan n l vd xue ble se giam.
Nang suit khai thac tang dang k l khi sii dgng ede thilt bj khoan, b l e x I p vd vgn tai ed cdng suit Idn. Thyc t l , tgi cdc md qugng cua My, Anh, Thgy D i l n , ngudi ta su dung cde thilt bj md lp thien d l b l e x I p vd vgn tai qudng blng phuang phdp khdng dudng ray khi khlu khdng chia t i n g d cac khoang sang cd chilu ddy Idn n i m ngang vd r i t thoai blng hp thing khlu duli vd buIng - cpt. P h i biln han ea, ngudi ta s i i dgng logi may xue cd d n g i u khdng Idn (khoang 5-6m), dung tich g i u 0,4-0,6m^, khdng gian lam vipe rpng 8m, eao 4m-5m. Khi chilu eao nhd han, s i i dgng cdc mdy ble x I p ca khi.
o l gom, cdo qugng thanh d i n g cgnh mdy XUC hole mdy b l e xIp, thudng s i i dgng may ggt cd trpng lugng 6-7 t i n , khi dd se nang eao dugc ndng suit b i c xIp qugng, ding thdi trong qud trinh di chuyin, may ggt cdn tgo ra dudng vgn chuyin cho godng t y hanh cung nhu may khoan di chuyen.
Hinh anh may xue, may ggt lam vipe d guang dugc the hipn tren hinh 3.
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<Xa„^ii&t.)C/ 1 ^,
Hinh 3. Mdy xue, may g^t Bang 1
Chieu sau eua than qudng
(m)' 23 75
75 50
Chieu ddy cua than qudng (m)
1,8-7,8 4,8-6,0 2,7 3,0
Dwang kinh trung binh eua
try bdo v? (m) 3,6-9,0
7,5 6
Khoang edeh trung binh giwa ede try
bdo v? (m) 7,5 15,0
12 12
Ton thit quang de lai tru bdo
ve, % 12 13,5
10 Phuang an van tai khdng dung dudng ray
trong khai thde h i m Id, thye t l khdng chf ed godng tu hdnh, md e6n sii dung ede logi 6 t6 tu d l vdi siic ndng d i n 5-6m^, da t h i hipn uu t h i vugt trpi d nhilu md qudng tren t h i gidi.
Sii dung mdy xue vd 6t6 t y d l ed t h i ble xIp vd van tai ede cue qudng Idn md khdng phai dap nhd Iln hai.
Vipe dp dung phuang dn van tai khdng dudng ray vd thilt bj ble xIp cd cdng suit Idn se anh hudng din phuang dn khai thdng khodng sdng.
Trudng hgp khai thdng blng gilng nghieng vdi gde d i e d i n 10-12° hodc Id blng, trong dd kich thude tilt dipn Id blng vd gilng nghieng khi dung oto t y d l Id 3,6x5m.
Trudng hgp khai thong bang gilng diing, khi qudng t i i guang khlu chuyin d i n mdy dgp, ddt d sdn ga vdi su dgng godng ty hdnh, 6t6 ty d l hoac k i t hgp godng ty hdnh (din Id vgn tai chinh) vd tdu dipn 6k van chuyin theo Id van tai trong godng vdi t h i tich Idn, d i n lOm^
Trudng hgp sii dgng cdc thilt bj cdng suit Idn, khlu guang cd t h i bang guang bgc trg hoac guang hg trin. Khlu blng guang bgc trg thudng duy tri mot bgc khi chilu ddy than qugng din 9m, cdn khi chilu ddy than qugng Idn han, thyc hien khlu bang mpt s l bgc, trong dd may ui se tgo nen gdc nghieng d n thilt eho mat
bgc 6k cd t h i chuyin ddn khoan ty hdnh khoan bgc tilp theo, ding thdi phai cd khoang khong gian ty do giu-a qugng da n l min vd vach eua ede bdc khoang 4m-5m.
Chlng giu vdch thye hipn bang each b l tri ede trg bao vp khong d i u , khde vdi b l tri theo quy lugt trong he thing khai thde buIng- cpt.
Trong nhilu trudng hgp, khi dudng Id ed chilu sdu Idn, trg bao vp blng qugng thay blng trg dd md, khi gap qudng cd gid trj vdi chilu ddy thdn qudng khdng Idn vd khdng ed dd md thi thay blng trg bao vp nhan tgo blng be tong.
Mpt s l thdng s l vd kich thude cua trg bao vp khi khai thde kem 6wgc t h i hipn trong bang 1.
Vipe khlu tgn thu tru bao vp dugc tiln hdnh sau khi khai thac vd chf thye hipn vdi cdc tru bao vp ehiia qugng ed gid trj eao.
Trong cdng nghp ndy, he thing thdng gid dan gian,tuy nhien trong mpt s l trudng hgp, ngudi ta khoan nhiing Id khoan chuyen dung t i i b l mat md d l thdng gid.
Bipn phdp ea ban nham dam bao an todn lao dpng Id d l phdng Id ndc, vi vdy sau khi no min d n thilt phai xem xet va logi tni cac lo hIng, phai thudng xuyen quan sat trgng thai eua vdch t i i dudng Id tiln trudc. CJ mpt so md quang ngudi ta sii dgng xe con ty hdnh d l kilm tra vdch, vdi san ty hdnh cd g i n viin kinh./.
KHCNM s d 2/2012* TAI LIEU VA THdNG TIN NUdC NGOAI
