Thong tin khoa hpc cong nghe mo / HIEN TUDNG THAN TIT CHAY VA MOT SO KET QUA NGHIEN CQU VE THAN TIT CHAY tai Viet Nam Recent years, the coal spontaneous combustion phenomenon TS TAKEHIRO iSEt has happ[.]
Thong tin khoa hpc cong nghe m o / HIEN TUDNG THAN TIT CHAY VA MOT SO KET QUA NGHIEN CQU VE THAN TIT CHAY tai Viet Nam Recent years, the coal spontaneous combustion phenomenon TS TAKEHIRO iSEt has happened at underground coal mines Mine fires by coat Chuydn gia tinh nguydn cao cip JICA spontaneous combustion have caused a great deal of damages ^^^- "-^ TRUNG TUY£N of natural resources, mining equipment and labor force, production ^'^" '^^.^ ^^^ ^^"3 nghd Md - Vinacom break down and labor productivity decrease In this paper, the ^'^" ^^P- ^^^- ^^^"^ ^^^" ^^^"^ authors represent the properties and mechanism of the coal spontaneous combustion phenomenon as well as some research results on determining the coal spontaneous combustion earned out by IMSAT recently Gid'i thieu Hign tupng than ty chdy da xay tgi mpt so md him 16 Vigt Nam thd'i gran qua Cdc vy chay dupc cho Id than ty chay dup'c liet kg bang eho thiy sy t i n that v l nguon lye, kinh phi vd m i t mdt v l tdi nguyen d l d l i phd vd'i cae vy ty chdy Tren thyc t l t i n tgi quan diem cho rdng than antraxit Id than 41 Khdc Tong thdng ndm -1 ndm 1 1 LO dQC via than 1 Cua giO 1 Than tOn tgi phay Via trdn s | p 1 Khdc 1 Khu i i m b i t d i u 10 chp 1 hoa Than lu'u tgi phay gan d i i m b i t d i u guong chp 1 S i p nOc d cuoi guong chp 1 Khdc KhSc Tong So lupng % Cor chd xay tu* c h l y Ty ehly duoc djnh nghTa la qui trinh vgt chit bj nung ndng ban thin vgt chit dxy hda d nhigt dd thSp, nhigt q u i trinh dxy hda tich ty thdi gian d l i eho ddn nhigt dd dat tdi ngudng ty bat Ida v l eudi cCing I I ty chay xay Lidn quan den hign tuong ty ehly eua than, cd nhieu g l l thi^t duoc dua de giai thich hidn tuong Tuy nhien, co ch4 than ty chly thyc sy chua ed duoc mgt sy thdng nh4t chung d l thda man cle ly gill khic Mgt s6 gia thiit chinh ve hign tuong ty chly duoc neu bao g6m: - Thuylt Pyrit - Hogt ddng cua vi khuin - Oja nhigt - Hap thy nude trorg than 1 LO khoan thdo 5 6 28 3,6 10,7 17,9 17,9 3,6 17,9 17,7 7,1 3,6 100 Phin irng dxy hda cua than Lien quan den elc gia thiet neu tren, elch IJ gill v l ty chly xuat phat tLf nhigt sinh q u i trinh ty dxy hda tich ty dgt den ngydng chly I I elch [j giai duoc chip nhin rdng rai TCr elch ly giai nay, elc bign phip ky thuat duoc sCr dyng d l ngln each than v l khdng bang vige trim Id vdi v | t lidu tro, chen cle khu vyc cd than tdn dpng bang vgt ligu tro hay phun vat lieu tro vao cle khoang hd, khe nyt ciJa than da duoc I p dyng rdng r l i va cd nhyng thinh cdng vigc phdng chong hign tuong ty chly Bang thong ke thdi gian d l xay ty chay than b i t d i u tiep xuc hole cd dilu kidn tilp xuc vdi khdng cua khoing sing than khu vyc Hokkaido KHCNM s d 7/2014 * AN TOAN MO Theo dd, 50% vu ty ehly xay dudi thing, 70% xay dydi thing va 90% dudi nam So sanh vdi dilu kign d Vidt Nam nhy c i c md Khinh Hda, Phin IVIl va Hdng Thii (TrIng Khe), hign tuong ty chly xay sau vai thing hogc vai tuIn dydng Id chuan bj cat qua via than d l than tilp xuc vdi khdng Dieu cho thiy, qua trinh dxy hda x l y than bat dau tiep xuc vdi khdng Theo dd, e l c khu vyc nhy guong Id chuan bj, cdt than hogc khu pha hda, mpt v l i thing dau la thdi dilm de xay hign tuong ty chay Nghien ciru v§ tinh t\f c h l y cua than antraxit tai Vigt Nam (1) Phyong phap cua Nga Phuong phip nghidn CUTJ v l than ty chly cua Nga I I phuong Thdng tin khoa hgc cdng nghe md phap dinh g i i tinh ty chly cua than theo chf so h i p thy d xy cua mau than Phyong phap nghien cu'u eua Nga dua hai thdng s6 lien quan den kha nang ty chay cua than v l thdi gian u nhigt eua mlu than Xic dinh hang so hip phu dxy dieu kien dang nhlet tfnh (U25) Phuong phip dya tren co sd sy dxy hda than bing phan tu" dxy dieu kien dang nhigt tinh Phyong phap tien hanh bing elch eho than khdi luong 40 gam v I o binh hap thu dygc nap khdng bp dieu nhigt Binh hap thu la loai binh thdt co cd the tich 600cm^ Phan dydi cua binh cd chu'a bdng thuy tinh d l y 5cm chu'a luong nydc nhd d l gly dp am khong dli Phia dudi binh h i p thy I I chupt t h i tich 200em= diing d l thu hdi tir binh hap thy Binh h i p thy v l chupt thu hdi duoc ndi vdi binh chan khdng t h i tieh 3000em' Sau 24h thio binh d bp dilu nhiet, lly m l u binh phin tich d l x l e djnh thinh phan CO2,02 va CH4 Sau dd, ngp lai khdng sgch v I o binh v l tilp tye dua binh v I o bd dilu nhigt; sau 24h Igi tien hanh lay m l u khdng binh d l phin tich Mirc dp tieu hao dxy buong h i p thy phan I n h kha nang ehly cua than duoc l l y theo g l l trj trung binh hing sd v|n t i e h i p phy dxy khoang thdi gian tir 50 d i n 250 gid Hang so vgn toe h i p phy dxy (ky higu U) dugc tinh theo cdng thirc: Hinh Sadd nguyin ly xic dinh hi sd hip phu dxy Trong dd; djnh theo phuong phip gia V - The tich khdng nhidt d l x l e djnh hg s6 v i n tdc h i p phu oxy tdi hgn dugc tiln binh (cm^); P- Ap suit hoi nydc bao hinh bing elch eho lOOgam than cd hat tir 0,9 1mm vIo hoa 25°C (mmHg); binh thep chuyen dyng Dat B- Ap suit khdng binh v I o tu s l y d nhigt dp nhlt (mmHg); (Snh gid Lay binh d l W; - Khoi luong cua than nhigt dp mdi trpng phdng roi (g); rut binh phin tich him t - Thdi gian bat dau q u i lygng CO2, O2, CH4, CO Mdi trinh h i p phy den l l y m l u m i u than lOOgam chi lam vdi (gid); mpt dai nhiet dp rpi bd mau di Thdi gian u nhigt duge tinh CO - Him luong dxy theo edng thirc: khdng (%); Ca - Him luong dxy ^ t,'-^-r.*'^^'"< (2) m l u lay sau 24 gid (%); 760 - Ap suat khdng d Trong dd; dilu kign tieu chuin G i l trj U2S dygc xae djnh T; Thdi gian u nhigt (ngly eho c l e m i u than khic dem); de dya ngydng ve tinh ty Tkp; Nhigt dp nung ndng tdi chly cua than.- Theo kinh han OK; nghigm cua Nga, g l l trj U25 Cp; Nhigt dung trung binh > 0,0016 thi x l e djnh m l u than cua than thdi gian tir cd kha nang ty chly r'=298+TKp(J/kg*dp); Xac dinh thdi gian u nhi$t To; Nhigt dp cua than trpng Thdi gian u nhigt duoc x l e nguyen khoi; KHCNM S 7/2014 • AN TOAN MO Thdng tin khoa hQC cdng nghe md qua mau than d l m l u than bj dxy hda Nhigt sinh q u i trinh dxy hda dugc tich tu v l l i m tang nhigt trdn chinh m i u than vl toln bd hd thdng dygc bd tri dang nhidt So dd thir nghigm t h i hidn hinh vdi hai hg thdng kilm solt nhigt dg, mdt de kilm solt nhigt Id thir nghidm v l mdt d l kilm solt q u i trinh tang nhigt cua miu than q u i trinh d xy hda miu sinh Vdi hai hg thdng nly, nhigt dd cua Id ti v i nhidt dp eua m i u than t2 ludn Trpng dd; (3) du-gc giy nhy q u i Ko: Hd s6 vgn toe h i p phy trinh thir nghidm Nhigt dp cua oxy d nhigt dg tdi hgn To=298°K m l u than t2 hiln thi tren man (m%g*S); hinh v l dygc deu dan ghi Igi KtKp; Hg s6 van tdc h i p phy sau gily ciia toan bp q u i oxy a nhigt dd tdi han TKP ; °K trinh thCr nghigm (m=/kg*S) Nguyen 1;^ hg thong; Oe giir dilu kign ding nhigt (khdng cd !i) (4) trao ddi nhidt), nhigt dp mau (lthan t2 ludn dugc giu' bang Trong dd; nhiet dd Id ti (ti = tz) Sensor TOK; Nhigt dp mdi trydng nhigt TCI (nhigt dp mau thir nghigm) va TC2 (nhigt dp Id) Id, °K (Tok = 273 + 28 = dygc diing d l dilu khiln nhigt SOfK); E; Nhigt lygng thoat dp ti = t2 Dau tien la cho ddng q u i trinh ty ii ndng den nhigt (khi N2) v I o m i u thdng dp tdi hgn de nIng len °C; R; Hang so khdng khi; R = 1.968 Koai/Kmol.°K Theo phyong phip neu VdMchfrQ tren, mdt so mau than tgi elc don vj da duoc x l e ffinh tinh ty chly theo gia tri hang sd h i p thu U25 (2^ Phygng phap dxy hda Phygng phap Nhgt Ban Banglfcfly^ • ' Thiit bi thw nghiem tw chiy Thilt bj thir nghiem dygc sir dyng d l x i c djnh tinh ty chly cua than bang vige cho lugng Hinh Buong thCf nghi$m miu than khoang Ig thif dogn nhi$t cua h$ thing cho nghigm dxy hda thdng qua vige d i n ddng khdng cd dxy di thd nghidm dxy hda miu than Wp; Dd I m l i m viee cua than (%); K: Nhigt hda hoi eua nydc (J/kg); M; Dp chira ty nhien eua than (m^); Q; Nhigt lygng q u i trinh h i p phu CH4 (J/m=); Kcp: -"Gil trj trung binh hg so hip phy oxy khoan nhigt dp tir 298°K