« '''' l E N CO THE DONG COP INHCNC CI CHO NHU CAU NANC LUONC THE KY 21 Nhieu lieu hda thach (than, dau md vd khi thien nhien) la ngudn tai nguyen thien nhien quan trpng nhat eua the ky qua va cho den ea[.]
«' l E N CO THE DONG COP INHCNC NANC CI CHO NHU CAU LUONC THE KY 21 TSKH H SITHOANG, TRAN MANH TR[ N hieu lieu hda thach (than, dau md vd thien nhien) la ngudn tai nguyen thien nhien quan trpng nhat eua the ky qua va cho den ea nay, cung cap hon 85% nhu cau nang lupng cho sy van hanh cua nen kinh te, ehu yeu la bao dam nhu cau dien nang, nhu cau nhiet nang va nhu cau nhien lieu dpng co cua mpi hoat ddng ngudi Tuy nhien, tru lupng cac ngudn nang lupng hoa thach la cd han va sy can kiet cua chung cung dang dupe dy bao bdi nhieu tinh todn khoa hpc Vi vay, da nhieu nam cac nha khoa hpc the gidi dau tu nhieu cong sdc cho viec tim nhdng dang ndng lupng khac vdi hy vpng cd the thay the mot phan hay todn bp cac nhien lieu hoa thach truyen thdng, hoa giai cac thach thdc ndi tren Sy tim kiem ndy da va dang dem lai nhieu qua quan trpng day trien vpng Td giua the ky 20 bien da trd ngudn cung cap dau md va thien nhien cho the gidi cang nhieu Hien cong viec thdm dd vd khai thae dau d day bien dang ngdy cang phat tnen va ngudi ta da cd the khai thde nhung md dau va md d nhCing vung bien cd myc nudc sau den ca nghin met Vd iinh vyc dau bien van dang tiep tuc tien nhijng vung nude sau, xa bd, Tuy nhien, bai viet xin phep khong de cap den ddng gdp edng tang cua bien ITnh vyc dau khf, ma ehi diem qua mot sd nhung tiem nang to Idn khac cua bien kha died the gdp phan phat trien nen ndng luong cho nhan loai the ky va nhung the ky tiep theo Hydrat metan: Gan day ngudi ta ndi nhieu den ngudn tdi nguyen het sye to Idn dudi day bien Id cac via hydrat metan Hydrat metan la nhung tinh the, dd cac phan ty nude (H2O) lien ket vdi thdng qua lye hut giua nguyen ty H cua phan td va nguyen ty O eua phdn ty khac (gpi la lien ket hydro) de tao nhiJng hoc ben chya cac phan ty khi, ehu yeu Id methan (CH4) cac Idp sa Idng hydrat metan d day bien cd cho CO be day den vai tram met Vi ehi ed the ton tai nhung dieu kien nhiet dp (thap) va dp suat (cao) nhat dinh nen hydrat metan chi dupe tim thay d nhijng vung bien cd dp sau nude tren 400 - 500 met (dp suat cao va nhiet dp thap) hodc d ede vung bien can hdn gan cac eye eua trai dat (d eac vung ap suat thap hdn nhung nhiet dp cung thap hdn) Ve tru lupng hydrat metan ed nhieu dy bao khac nhau, nhien, eac tac gia khao sat deu thdng nhat vdi Id het sye Idn Dy bao gan day (2004) dua sd tir den X 105 met khdi Con sd xap xi tru lupng tat ca eac nhien lieu hda thach cong lai (than, dau, khi") Theo ban dd phan bd thi day bien d rat nhieu vung vdi dp sdu tren 500 met nude va d cac vung cue cd chda hydrat metan vdi dien tich vd dp day khdc (xem hinh 1), Cho den chua cd nudc nao khai thde hydrat metan d quy md edng nghiep, nhien, then vpng eua viec khai thde no thdi gian tdi Id khong nhd Nhat Ban, theo thdng bao tren "The Time" ngdy 14/4/2008, da phat hien trd Thdng + - 2009 [ J ^ J ^ ^ | 15 lupng xac minh 39 TCF (1,1 nghin ti met khdi) metan ede via hydrat dudi day bien TrU lupng dy bdo la khoang 7,5 nghin ti met khdi Vdi tru lupng tren TCF, nude Nhat cd the sd dung 14 nam md khong phai nhap kha'u thien nhien hda Idng LNG (mdi nam Nhat nhap khoang 62 trieu tan LNG) Dy dinh nam 2016 dy an khai thae thuong mai hydrat metan se bit dau trien khai cac qudc gia Trung Qudc, Han Qudc, Canada cung dd thdng bao tim thay cac via hydrat metan d them luc d|a Ndm 2006 Trung Qudc quyet dinh chi 100 trieu USD cho c a c d y a n hydrat methan Hien ngudi ta cho rang, phUdng phap khai thae hydrat metan kha thi nhat la phUdng phap ap suat (depressurization), nghTa Id lam giam ap suat de pha vd cau true cac tinh the hydrat, dd, vd nude tach khdi Tuy nhien, tang nhiet dp va giam ap suat eua mdi trudng xung quanh nhat dinh se gay sy pha huy cau true tinh the va dd metan cung vdi nhung khac se dupe giai phdng vdo bau quyen cua trai dat Khi metan la doe, nhung dieu quan trpng hdn ea la kha ndng gay hieu dng nha kinh eua no thi cao hdn khiC02 khoang 10 Ian Nhu vay, neu metan tycac Idp hydrat dupe "giai phdng" vd thoat vao bau quyen thi nguy co hieu dng nha kinh la het sye nghiem trpng Hinh Sit phan bo hydrat metan tai cac vung bien i^^^Hnui ^ « ^ ^ ^ JUB^^S^^^S^^ ^^^^^I^^^H K^ WS*' •*i hinh Thiet bi Cot nwdc dao (OWC) de chuyen doi nang Iwcfng dien nang dong sdng vung bien khac deu khac Chang han vung vinh Fundy (Canada), bien dp dao dpng thuy trieu rat Idn, den 18m, hoac d vung bien nudc Anh (eda sdng Severne), bien dp dao dpng thuy trieu la 14m, dd, vung bien Baltic bien dp dao ddng thuy trieu la khong dang ke Gidng nhu he thdng chuyen hda nang lupng sdng dien nang, he thdng thiet bi chuyen hda nang lupng thuy trieu dien nang cung bao gdm hai bp phan: bd phan thu nang lupng thuy trieu va bp phan chuyen hda nang lupng thuy trieu dien nang Tren the gidi, y tudng chuyen nang lupng thuy trieu dien nang da ed ty rat lau vdi de an cua Thomas Fulljames nam 1849 Rat nhieu de an dupe xay dyng sau dd, nhung vi xay dyng nhd may dien thuy trieu qua ton kem, gia dien thuy trieu tinh rat cao so vdi dien td nang lupng hda thach, vi the nhieu dyan phai gae lai Sau cuoc khung hoang nang lupng d nhung nam 70, cac dy dn ve dien thuy trieu dupe xem xet lai va da'y manh d nhieu nude, dd dang chu y nhat la dy an dien thuy trieu ciJa Anh d eda sdng Severne de nghj trude day da dupe sy ung hd cua chinh phu thdng qua nam 1978 Nhieu dy dn nhd may dien thuy trieu d Phap tren eda sdng Ranee, d Canada tren vinh Fundy, d Nga tren vung bien Murmansk dupe xay dyng vdng vdi thap ky gan day Tiem nang dien thuy trieu tren the gidi rat Idn, khoang tren 300.000 ti Wh/nam Nhung 18 Bl«n Vi^t Norn Thang U 2-2009 De chuyen hda nang lupng thuy trieu dien nang, thudng phai xay dyng cac dap chan d eda sdng nhung vung ed bien dp dao dpng thuy trieu Idn nhat, sd dung the ndng (potentiel energy) CLia thuy trieu d mdc thap nhat va cao nhat (tidal barrage) chuyen dpng ndng lam quay tude bin may phat dien San xuat dien tynang lupng thuy trieu theo edng nghe rat gan vdi san xuat dien d cac nha may thuy dien, chi khac la nudc cd the chay theo hai hudng, luc thuy trieu len hoac luc thuy trieu xudng Khi thuy trieu len, cac eda edng tren dap 6\jgc keo len, cho phep vung luu vyc ben dap ngap day nude Khi thuy trieu xudng, cac eda dap dupe ddng lai, bupe nudc ben dap thoat ngoai bien di qua he thdng tude bin nudc gan d ben dudi eda dap He thdng hoat dpng nhu tren gpi la he thdng thuy trieu xudng (hinh 4) Tuy nhien, cung cd he thdng hoat dpng theo kieu ngupe lai, tdc he thdng hoat ddng thuy trieu len Sluice G4es High Water IMaifc Etfuary Floor Hinh He thong dap chan ci^a song de san xuat dien theo kieu thuy trieu xudng The nang lupng td dap thuy trieu tao phu thupc vao chieu cao myc thuy trieu len cao va xudng thap, ddng thdi phu thupc vao the tich nudc tieh ehda dap O Anh Dy an nhd mdy dien thuy trieu Severne (Anh) dang dupe xay dyng vdi he thdng dap bac qua eda sdng Severne; chieu cao cua thuy trieu day dat 14m, cao ddng hang thd hai tren the gidi Dap thuy trieu Severne ddi 18 km, ndi hai bd gida Cardif (xd Wales) va Brean Down (Anh) Dy an nhd may dien thuy trieu Severne hodn se ed edng suat Idn nhat the gidi, 8.600 MW, hang nam cd the san xuat 17 ty kWh dien nang, cung cap 5-6% nhu cau dien cho nude Anh va xd Wales, tuong duong vdi nha may dien hat nhan the he mdi nhat O Phap, tren sdng Ranee vung Bretagne cung da xay dyng dap ddi 750m chdn ngang sdng, da lap dat 24 tude bin, tdng edng suat dien 240 MW, cung cap san lupng dien hang nam 600 tneu kWh cho vung Bretagne Nha may duoc khanh nam 1966, la nha may dien thuy trieu dau tien tren the gidi Ipi dung the nang cua mdc thuy trieu cao vd thap vd da hoat ddng lien tuc 40 nam lien cho den 300 kW, sau dd dd trien khai thuong mai he tude bin 600 kW va Idn hon nham tien tdi xay dyng mdt lang tude bin dudi day bien (turbine farm) vdi cong suat tdng edng 10 MW Dudi ddy la hinh anh he thdng san xuat dien thuy trieu bang tude bin dudi bien thuong mai dau tien tren the gidi SeaGen cong suat 1,2 MW nang 1.000 tan, dupc lap dat nam 2008 tai Strangford Lough (Bac Ireland) Tude bin SeaGen cd rotor, dudng kinh ednh quat 16 m, tdc dp quay 10-20 vdng/phut, dupe dat sau dudi ddy bien 400m edng ty Marine Current Turbines Ltd che tao (hinh 5) Theo dy kien, den nam 2010 se san xuat khoang 300 tude bin hang nam Nang lupng eua cac ddng hai luu (tide stream): Hai luu ed hau het ede dai duong cua trai dat, ed the di chuyen tren dp ddi hdng ngan kildmet va ed edng suat eye Idn Cac hai luu be mat dUdc di chuyen bdi gid va ed xu hudng chay theo xoan de cung chieu kim ddng hd d Bac Ban Cau va ngupe chieu kim ddng hd d Nam Ban Cau Cac hai luu ngam dudi sau chuyen ddng sy chenh lech gradient nhiet dp vd ty trpng nude Cde hai luu di chuyen vdi mot tdc dp khac Nhung hai luu dudi mat nude ed tdc dp cao, dat tren m/s (thudng td 2-2,5 m/s) dupc Ipi dung de lam quay tude bin phdt dien Nhi/ng tude bin ve cau tao cung tUdng ty nhu tude bin gid, nghla Id Ipi dung dpng ndng (hydrokinetic) cua hai luu ngoai dai dUdng lam quay tude bin Dieu dang luu y Id, theo cong thye tinh toan, edng suat tude bin dudi bien Ipi dung ddng hai luu ti le bac ba vdi tdc dp eua ddng chay Anh Id nude tien phong viec trien khai y tudng sd dung tude bin nhu tude bin gid de chuyen hda nang lupng ddng hai luu thdnh dien ndng Vdi sy hd trp cua Scottish Nuclear va NEL, ndm 1994, IT Power da thy nghiem va xay dyng mot nguyen mau nhd tude bin loai canh, edng suat 10 kW lap dat tai eo bien Corran Narrows thudc vung bien Loch Line Tren cd sd cong nay, IT Power da lap edng ty Marine Current Turbines Ltd (MCT) de trien khai mdt phien ban thiet ke mdi cua tude bin SeaGen dupc Idp true tiep dudi ddy bien Ndm 2002, MCT bat dau thd nghiem mot tude bin edng suat 1 r^2^^^^^ ?•'•J ^ " iF ^llm£:^^ = „2-^^ i 11 •! 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