KH&CNN 90*11/2009*2 LUA CHON CONG NGHE NHA MAY DIEN HAT NHAN THE HE THUf HI • • • • • • Da CO hoi thao qudc teve dien hat nhan cua Viet Nam d Ha Noi thang 10/2008 & day CO ban bao cao Ida chgn cong ng[.]
KH&CNN-90*11/2009*2 LUA CHON CONG NGHE NHA MAY DIEN HAT NHAN THE HE THUf HI • • • • • • Da CO hoi thao qudc teve dien hat nhan cua Viet Nam d Ha Noi thang 10/2008 & day CO ban bao cao Ida chgn cong nghe nha may dien hat nhan the he thffba cua TS Dinh Due Hffu Ong dang la cd vain cho Vien Nang luang hat nhan qudc gia Viet Nam va lam cd van Chuang trinh dien hat nhan cho nhieu qudc gia tren the gidi Tap chi Khoa hoc & Cong nghe Nhiet nhan thaiy day la mot ban bao cao CO nhieu thong tin tdt, dap ung nhu cau hien ve Ida chgn cong nghe dien hat nhan nen xin duac gidi thieu noi dung ca ban ban bao cao GIOI THIEU TONG QUAT Nhieu qudc gia tren the gidi da xay dffng nha may dien hat nhan (NMDHN) san xua't dien nang Hien dien hat nhan chiem khoang 16% tdng san Iffdng dien tren the gidi Cac qudc gia cd be day cdng nghiep va ve dien hat nhan tren the gidi, d i n dau la Hoa Ky tiep la Phap, Nhat Ban,Nga, Han Qudc, Canada, Trung Qudc c6 nhieu loai Id khac n-hau nhffng tffu chung cd hai loai 16 chinh la Boiling Water Reactor (BWR) - Id nffdc soi (hinh 1) va Presure Water Reactor (PWR) - I d nffdc ap suat (hinh 2) Hoa Ky la qudc gia dan dau cac n6 Iffc nghien cffu, che tao va xay dffng hang loat cac NMDHN the he I va san xua't Iffdng dien hat nhan kha Idn cac thap nien 60 va.70 cua the ky trffdc Tap doan General Electric (GE) tap trung che tao 16 nffdc soi va tap doan Westing House che tao 16 nffdc ap suat Nhat Ban hop tac ca GE va Westing House de che tao ca 16 nffdc soi va 16 nffdc ap suat Phap hgp tac vdi Westing House tap trung nhat che tao 16 nffdc ap suat Rieng Canada che tao 16 nffdc ap suat nhffng sff dung nffdc nang de giai nhiet 16, loai 16 c6n ggi la 16 ap suat nffdc nang Han Qudc hgp tac vdi Westing House xay dffng 16 nffdc ap suat va nhd Canada xay dffng 02 16 ap suat nffdc nang nhffng den Han Qudc da tap trung vao 16 nffdc ap suat Trung Qudc da hgp tac vdi Hoa Ky va Phap xay dffng hang loat cac 16 nudc ap suat va khong phat trien 16 nudc sdi nffdc vdi ap suat Idn dffgc dan thang den tuarbin de quay may phat dien Lo nffdc ap suat gdm he thdng nffdc tach biet (Two separate loops) va nffdc khong pha trdn vao He thdng so cap (Primary loop) cd nhiem vu hap thu nhiet tff cac phan ffng 16 dffdi ap suat rat cao va d6ng nffdc ndng dffgc chay qua he thdng dng hap thu nhiet de sinh hai binh giai nhiet (Steam Gnerator tubing) Tai day nhiet dffgc he thdng nffdc thff hai (secondary loop) nhan nhiet va bien nffdc hai nffdc dffdi ap suat eao, dong hoi nffdc dffgc dSn vao tuarbin de chay may phat dien Boiling Water Reactor System Hinhl Lo nudc soi Nhffng khac biet ve cong nghe giffa 16 nffdc soi va 16 nffdc ap suat, ffu nhffgc diem cua hai loai 16 la: L6 nffdc soi tri mot he thdng nffdc (One single loop), nffdc hap thu nhiet tff cac phan ffng hat nhan 16 de bie'n hoi nffdc va hci Hinh Lo ap suat KH&CNN - 91*01/2010*3 L6 nffdc soi c6 ffu diem la khong can binh giai nhiet, van hanh dffdi ap suat va nhiet thap nen nudc dan vao van hanh true tiep tuarbin ma khong can phai qua he thdng trao ddi nhiet nen thiet ke va xay dffng d5 tdn kem hdn Nhffgc diem la hOi nudc cd chffa chat phdng xa va c6 kha nang thoat ngoai moi trffdng Ld ap suat c6 ffu diem la hai nffdc dan vao van hanh tuarbin khdng chffa chat phdng xa vay, tranh dffgc chat phdng xa thoat ngoai Nhffng c6 nhffgc diem la cac dng d i n nffdc binh giai nhiet d l bi nfft, thiing dan de'n nffdc CO nhiem phong xa tran sang he tuan hoan nffdc thff va thoat mdi trffdng ben ngoai Ap suat va nhiet van hanh Id rat eao nen van hanh khd khan han NHA M A Y D I E N HAT NHAN THE HE THLF II L6 the he thff c6 he thdng cap nffdc an toan trffdng hgp khan cap He thdng an toan giai nhiet ciia 16 qua cong kenh va phffc tap, de dam bao an toan cho 16 phan ffng khong bi mat nffdc d i n den chay 16 va dam bao nha chan 16 khdng bi vd Mgt he thdng cung cap nffdc lam nguoi 16 va lam mat nha' chan 16 dffgc xay dffng He thdng bao gom hai nhanh doc lap nhau, mdi nhanh c6 cong suat 100% bao gom motd, bdm, van, dng d i n , nguon dien, day cap dien, he thdng may dieu hda khong khf, cac thiet bi phu trg chdng dgng dat, thie't bi chuan mffc an toan, chffdng trinh chay thff va bao dffdng dinh ky He thdng can rat nhieu vat lieu xay dffng, chiem nhieu dien ti'ch, dau tff ban dau tdn kem, chi phf bao hanh va bao dffdng rat Idn He thdng v i n tiem an nhieu nil ro vi le thugc vao cac bd phan ca dien va ngudn dien de van hanh cac ca phan ciia he thdng Luat le CO nhieu bat cap, can giay phep de xay dffng va van hanh nha may, viec tao riii ro cao cho nha dau tff: Trffdc day, mudn xay dffng NMDHN, nha dau tff can cd giay phep xay dffng (Construction licence), nha may xay gan xong thi xin giay phep van hanh (Operation licence) Hai giay phep tao ca hgi cho eac nhom chdng ddi dtmg luat phap de gay kho khan cho nha dau tff xin dffgc giay phep van hanh NMDHN Tai Hoa Ky, da cd nhieu nha may xay xong nhffng phai bd dd va trd ddng sat vun, gay thiet hai nhieu chuc ti USD Hoac cd nhieu nha may keo dai them den nam mdi cd giay phep van hanh gay thiet hai rat Idn cho nha dau tff Day cung la ly chinh khien nganh dien hat nhan da phai ngffng lai hdn 20 nam qua tai Hoa Ky va cac nffdc Chau Au Xay dffng tai hien trffdng khien keo dai thdi gian xay dffng qua 10 nam: NMDHN the he II dffgc xay dffng tai hien trffdng, cd qua nhieu cdng viec can tien hanh mgt liic hoac theo mgt chu ky nhat dinh, cac ddi hoi ve kiem tra chat Iffgng, giam sat an toan, thdi tiet khien cac hoat dgng xay dffng cho hieu qua thap dan tdi thdi gian va khdi Iffgng cong viec vffgt dinh mffc lam tang gia va thdi gian thi cong N H A M A Y DIEN HAT N H A N THE HE THU' III Tai nan NMDHN Three Mile Islands tai Hoa Ky va Chernobyl tai UCraina la hai bai hgc dat gia d6i hdi c6 bffdc dot pha ve cai tien cong nghe dan den che tao NMDHN the he thff III: Tai nan nha may Three Mile Island tai Hoa Ky vao nam 1979 Day la nha may sff dung Id ap suat hang Westing House che tao, cong suat 1.000MW Khdi dau true trac nhd va mat nguon nffdc d he thdng thff d i n den thieu nffdc binh giai nhiet khien he thdng nffdc 16 tang ap suat va nhiet d i n den van an toan tff dgng md de ap suat 16 Nffdc nong chay qua van an toan va nhiet ke d dffdi dudi van v i n chi 100°C ap suat dffdi van thong vdi ap suat khdng Ky sff chi huy nha may da lam tffdng la van an toan v i n ddng va khong biet rang 16 dang bi mat nffdc tram trgng (Ky sff chua hieu thau dao nguyen ly nhiet ddng hgc Isentropic process) Dang le d thdi diem van phai dffgc d6ng lai va he thdng cung cap nffdc an toan cho 16 can dffgc van hanh de cung cap day dii nffdc cho 16 Trai lai ky sff chi huy da cho ngffng bam nffdc vao 16 dan den 16 cang thieu nffdc nhieu han gid trdi qua , lanh dao nha may mdi dieu chinh va cung cap nffdc lai cho 16, nhffng da qua t r i va gay thiet hai n|ng ne Tuy nhien, cac he thdng an toan khac v i n hoat dgng tdt va chat phdng xa khdng thoat ngoai mdi trffdng Qua tai nan nay, da rut dffgc bai hgc quy gia; Thiet bi nha may dffng vffng trffdc mgt tai nan nghiem trgng cho thay tieu chuan an toan ky thuat dat cac chi tieu thiet ke Tai nan xay yeu td ngffdi chffa dffgc dao tao diing mffc Sau tai nan chiing ta da riit dffgc nhieu kinh nghiem de sffa chffa ke ca phan thiet ke he thdng va phan quan ly van hanh nha may 4*KH&CNN - 91*01/2010 ChUdng trinh cai tien 16 tffng budc (Evolutionary Technology) va chUdng trinh thiet ke Id mdi (Development Technology) Vao nhffng nam 1980, tai Hoa Ky va cac nudc Chau Au ngoai trff Phap da ngffng xay dgng NMDHN vi cac ly chinh nhu xin giay phep qua khd khan vi ap lUc tff cac nhdm chdng ddi, thdi gian xay dUng ntia may lau, anh hUdng tieu cue cua tai nan Three Mile Island, cac yeu td day gia NMDHN len qua cao so vdi cac nha ma/^dien sff dung than, ddt chua ke nha dau tu rat lo so khoan dau tu bi mat trang khdng dugc cap phep de van hanh Trong thdi ky am dam nay, Han Qudc Nhat Ban, Trung Qudc va Phap vin tiep tuc hdp tac vdi GE va Westing House de thUc hien chuong trinh cai each tffng budc (Evolutionary) dua vao cdng nghe the he thff II va ky hieu dUdc dung c6 chff A (Advantage) dffng trudc ntiU APWR 16 ap suat va ABWR id nudc sdi va the he thff III 16 cai tien dUdc cdng nhan Westing House theo dudi mdt hudng ti'ch cue hdn va nghien cffu lai tff dau va chCi trUdng thay ddi Idn thiet ke' Id va phuong phap xay dung nham nang cao he sd an toan, thdi gian xay dung dUdc nit ngan, gia dau tU dUdc giam dang ke Phuong thffc dugc ggi la (Development) NMDHN the he III kh^c the he II cac diem sau: cac chuyen gia van dUa vao thiet ke cd ban cua Id the he II de nang cap cac mang quan trgng nhu thiet ke Id an toan hon, hieu suat phan ffng cao hdn, he thdng theo ddi Id dUdc thay the bang thiet bi dien tff tdt hdn, nang cap cac he thdng cung cap nudc de dam bao 16 ludn khdng bi mat nUdc Quy trinh xin phep chi cdn mgt giay phep xay dUng va van hanh, ap dung cdng nghe chieu va phan mem quan ly xay dung riit xudng mdt nffa trung binh la nam Tdng gia 30% Rieng Westing House, Hoa Ky chij trUdng vffa cai each vffa lam mdi, ho nhan manh tdi cac ffng dung cdng nghe thu ddng (Passive), ap dung ldi the dinh luat trgng trUdng (Gravity Force), nhiet dugc truyen tff mdi trUdng ndng sang lanh de tao nen hdp luu nhiet ddng hoc (Natural Circulation) Phuong phap se giup nha thiet ke loai bo dUdc rat nhieu thiet bi cd dien va khdng can den ngudn dien nang de van hanh cac he thdng an toan cua NMDHN vdn la van nan hang dau ciia cac nha van hanh vi phai dd'i dien vdi trudng hdp mat dien din den nhieu he thdng phdng ngU an toan bi mat dieu khien Sau day la bang so sanh cac chi tieu kinh te ky thuat cac NMDHN the he III tan tien nhat dugc cac nudc gidi hieu va ban tren thi trUdng the gidi (Bangl) Mffc dp hoan thien ciia NMDHN the he rhff III dUdc the hien d hinh 100 -r ^^X"-"''^' / /L, 1 j f^ J / €Xibng 1:Mifc 36 hoan thifen ve ky t>«4t x ^