KHOA HOC NANG LlTONG
Trong thdi gian tir nam 2001 ct4n 2006, IAEA da chii tri thiTc hien cac du an Hdp tac Vun^ chau A Thai Binh DUtfng (RAS/8/089, RAS/8/094, RAS/8/099) ve "Lcrt fch cua viec ufng dung cac phUdng phap phan tich ky thuat hat nlian trong ky nghe khai khoang doi vdi viec tham dd va khai thac khoang san" nham muc dich gidi thieu, trinh dien va chuyen giao cac ky thuat phan tich hat nhan hien dai trong cac linh vUc khai thac than va md kim loai. Viet Nam va Trun^
Qudc la hai nUdc dUdc chpn xay dUng Phong thi nghiem Vilng de md cac khda tap huan va hoi thao qudc te phuc vu cho muc dich tren. DU an da phoi hd|> tdt vdi cac ddn vj trong nganh Than: td chufc nhieu hdi thao qudc te va qudc gia; trinh dien thiet bi tren hien trUdng va dUa nhieu can bd nganh than di tap huan d nUdc ngoai. Nam 2008, thdng qua dU an RAS/8/107, IAEA da chuyen giao ky thuat, cung cap vat tU ky thuat chu yeu cho Viet Nam va giao trach nhiem hoan thien phan thiet bi.
THIET BI PHAN TICH DO TRO THAN BANG KY THUAT
P C H A A
TS. N G U Y i N THANH TCIY, TS. TRjNH VAN GlAP Vien Khoa hpc va Ky thuat hat nhan - Vien Nang luong Nguyen tir Viet Nam
EE NANG LUONG VlgT NAM SO ,' i tl02 (Thang 10+11/2013)
KHOA HOC NANG LUONG
3U0C IAEA cung cap nguon phat ncrtron, bang kinh phi doi dng :hdng qua de tai cap Bp (2009 - 2011), ma so OT.03/09.NLNT, /ien Khoa hpc va Ky thuat Hat nhan (thupc Vien Nang luong
>4guyen tdViet Nam) da xay dung thanh cdng he thiet bi phan tich dp tro than bSng ky thuat PGNAA {kich hoat notron- gamma tdc thdi). Bai viet gidi thieu he thiet bj nay va cac dng dung tiem nang cua nd trong nganh Than dViet Nam.
Ky thuat phan tich PGNAA
Ky thuat phan tich bang phddng phap kich hoat notron- gamma tdc thdi (PGNAA) la mot trong nhdng ky thuat phan tich tien tien, hien dai, dang ngay cang dUpc dng dung rdng rai vao phuc vu san xuat cdng nghiep va ddi sdng. L/u diem cua phuong phap do nay la phan tich nhanh, ket qua kha chinh xac, khdng phai gia cdng mau, qua trinh phan tich khdng bj anh hudng cDa dieu kien mdi trudng, va phan tich duoc hau het cac nguyen td trong bang tuan hoan Mendeleev... 6 cac riLfdc tien tien, cd the tim thay nhieu dng dung cua phuong phap nay nhieu linh vUc.
Tuy nhien, do viec xay dung he do sddung ky thuat nay ddi hdi phai cd trinh dp ky thuat - cdng nghe cao va ngudn kinh phi kha Idn, cho nen thdl gian qua, nd van chua dupc dng dung nhieu dViet Nam. Dac biet, hifn nay viec dng dung ky thuat hat nhan dang dupc trien khai manh, nhdng dng dung ky thuat PGNAA chua dupc quan tam dung mdc.
IVIay nam gan day, da bat dau cd nhieu cO sd cdng nghiep sd dung thiet bi PGNAA nhung cac thiet bi nay deu phai nhap ngoai. IVldt sd vien cd de tai nghien cdu ve ky thuat PGNAA, nhung hau nhu chda cd de tai nao nghien cdu che tao he do.
Chinh VI Uu diem noi bat cua PGNAA nen chac chan cac thiet bi si> dung ky thuat PGNAA se phat trien de dap dng nhu cau tudpng hoa trong qua trinh cdng nghiep hoa [1,2].
Nguyen ly co ban cua PGNAA la khi tia notron chieu vao mau do, trong mau lap tdc phat ra cac tia gamma (nen cd ten goi la kich hoal notron gamma tdc thdi, hinh 1). Cudng dp tia gamma phu thudc vao nang lupng cua notron va ham lupng cac nguyen td cd trong mau. Khi thdng lupng cua ngudn natron khong doi (trudng hpp diing nguon dong vi hoac vdi cac thdng sfi ve ddng, ap xac dinh khi dung ong phdng), cddng do lia gamma chi cdn phu thupc vao ham luong cua cac nguyen td vJ dac trung cho cac nguyen to cd trong mau bi chieu.
Tuy nhien, khi bi kich hoat bdi notron, trd mot nguyen td Hydro chu yeu sinh ra mdl mdc nang lupng 2223keV, moi nguyen td khde se sinh ra rat nhieu mdc nang lupng gamma cd cddng dp khde nhau, nhieu nguyen to lai cd nhieu mdc nang lUpng dan xen nhau. Nhu vay, mdi mpt viJng pho nang lUpng thu nhan duoc (dil hep) se bao gom kha nhieu nang IUpng khac nhau ciJa nhieu nguyen td.
N^u diing he dau dd do phan giai cao (chSng han he dau dd Ge sieu tinh khiet) ta cd the tach cac vach pho gamma tdc thdi nSy theo nSng lupng, ISm co sd nhan dien va xac djnh duoc
ham Idpng cua cac nguyen to. Cdn khi diing cac he dau dd cd dp phan giai thap hoac vda phai, thi cd the dUa vao loan hpc de tinh duoc ty le ddng gdp vao mdt mdc nang luong cua moi nguyen td, t d d d tinh ra dUOc tdng cUdng dp cac tia gamma dac trung sinh ra cua moi nguyen to, tren cd sd do tinh dupc ham luong cua nguyen to dd cd trong mau phan tich.
Tinh chat nay cua ky thuat PGNAA, ddpc dng dung trong che tao thiet bi phan tfeh xac dinh nhanh dp tro than; phan tich cac nguyen td trong than, trong xi mang va trong cac vat lieu khac.
Hinh 1 - Vung xdyra tuang tdc Prompt gamma xung quanh dau thu hgt nhdn
Thiet bj phan tich do tro than bang ky thuat PGNAA Duoc Bd KH&CN giao thuc hien de tai;"Nghien cdu xay ddng he thiet bi phan tich dp tro sd dung ky thuat PGNAA vdi nguon phat natron",ma so DT.03/09.NLNT, tap the can bd khoa hpc cua Vien Khoa hoc va Ky thuat Hat nhan tham gia de tai da che tao thanh cdng he thiet bi phan tich nhanh dp tro sd dung ky thuat PGNAA. So do khdi chdc nang cua he thiet bi tren hinh 2.
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npwn nuoi 11 ghep noi USBl
Mi\ tmh tjw II 10 lim, bmi dien pbo, on dnfa pbo
Hinh 2-Sado khoi chdc ndng cua he thiit bi thiit bi phdn tich nhanh do tro sddung ky thudt PGNAA
Hinh 3, la cac phan dien t d che tao gom dng thu dat trong thiing do, hdp xd ly tin hieu va may tinh, hinh 4 la phan cOcua he thiet bi.
Nguyen ly chung cua he thiet bj phan ti'ch dp tro than bSng ky thuat PGNAA nay la sd dung tia natron phat ra td nguon dong vi Cf-252 chieu vao dong than, mau than bj kich hoat bdi ncrtron va phat ra cac tia gamma, cac tia gamma nay tan xa
\ , \ N G LUONC. VII" I NAM So 101 + 102 (Thang 10+11/2013) | I
KHOA HOC NANG LUONGI
trong mau than va di tdi dau thu hat nhan. Dau thu thu bdc xa gamma chuyen doi thanh tin hieu dien va truyen ve hop xd ly tin hieu roi truyen sang may tinh va duoc bieu dien dddi dang pho nang luang; phan mem phan tich phd cd nhiem vu xd ly, tinh toan tren phan phd cua tia gamma tdc thdi va tinh ra gia trj dd tro than cua mau phan tich. Hinh 5 la hinh anh pho nang Idpng cua mpt mau than (toan pho va phan nang Idong cao)
Hinh 4 - Phdn cacua he thiet bi do gom hop chda nguon vd thung do mau
Thiet bj phan tich theo ky thuat PGNAA la mdt trong nhdng loai thiet bi phan tich nhanh (thdi gian khdng qua 15 phut/Ian), ket qua kha chinh xac va dac biet ia khdng phai gia cdng mau, phan ti'ch do tro khdng bi anh hudng bdi thanh phan kim loai nang, dd am trong than va cac dieu kien mdi trudng khac,... He thiet bi che tao, sd dung ngudn Cf-252 cd thong luang 0,85x106n/s, luong mau can cho mot lan phan tich vao khoang (650 - 750)kg.
ill Hi
Hmh 5 - Pho ndng lugng PGNAA phdn tich than: Todn pho vd phdn NL cao (ben phdi)
Oieu quan trong khi che tao thiet bj hat nhan la yeu to dam
bao an toan bdc xa cho ngudi sd dung va moi trUdng. Bit\^
la ket qua do lieu khi danh gia an toan bdc xa he do. f Bdng 7. Ket qua tieu bdc xa gay bdi notron va gamma d I S ngoai hop chda ngudn (khi he khdng lam viec) va b^n ngoai thiing do (khi dang phan tich mau) tai vi tri each tam 1 m v a ^ .
1 0,40 2,1 0,97 3,50 2 0,15 1,50 0,33 1,80 Lieu duac phep ddi vdi ngudi lam viec trong mdi truong phong xa la 5 |jSv/h
Dd tro cua mSu phan tich dupc xac djnh bang cdng thu'c:
Apt (%) = 42.564 * (RAT OF 570-1570 BY 260-340) + (-42.758)[I, [RAT OF 570-1570 BY 260-340) la ty sd gida hai sd dem,s6derr viing nang lifOng cao, t d kenh 570 den kenh 1570vas6dem viing nang lUong t d kenh 260 den kenh 340; He sda-42,554 va b ^ - 42,758 dUoc xac dinh bang thuc nghiem tren cacmeu than khu virc HaTu.Do thUc nghiem xac dinh dd tro CLia4inau than, vdl 52 lan do, cd 3 ian cosai sd tuyet ddi > 1% nhutig' 1,2%, cac phep do cdn Iai deu CO sai so < P/o.Vdiketquaflodi tro va sai sd nhd vay la hoan toan cd the chap nhan du'oe He PGNAA phan tich do tro than co cac thdng so ky thuat chinl- sau day:
^ Sd dyng ngudn notron Cf-252 cd cudng dp (6/2011) la 0,85>
106n/s
^Thiet bi do sddung dau thu hat nhan BGO kich thUdcSlxSImm do hang REXON che tao, ADC cd dd phan giai 2000 kenh.
''Thiet bi cdchedd t u o n dmh pho, gidi han trdi kenh toi dale 4 kenh.
^Thdi gian phan tich mau than cho ket qua tin cay tiJ500s- 1000s.
* Khoi luang mau than phan tich la 700 kg.
•' He do ket ndi vdi may tinh qua cdng USB, chay tren mo:
trudng WindownXP.
^ Khoang each td thiing do tdi hdp dien tif (phdng do) la 30met
* Co khda de bao ve nguon phdng xa khi he do khdng lamvief Phat trien dng dung cua ky thuat PGNAA
Thiet bi sd dyng ky thuat PGNAA da thanh cdng trong viecXJi dmh nhanh dd tro than, dang tiep tyc nghien cutJ hoan thif'' them cac chdc nang sau day;
" Hoan thien ky thuat phan tich: Tren ca sd cong suat/thong luong ngudn phat natron xac djnh cau hinh dotoi lAJdegia^
khoi luang mau than, tim thai gian do hpp ly vaxaydu"?
dudng chuan cho thiet bj vdi tdng viing than khac nhauciViEi Nam de tang do chinh xac phep do, sai sd tuyet doi <1%P'5'
CE NANG LaONG VIET NAM Sd 101+102 {Thang 10+11/20!;
'Chuyen thiet bj phan tich trong phong thi nghiem thanh thiet bj phan tich hien trudng. Vdt cau hinh hien tai nhutrenhinh 4, viec phan tich dupc thiic hien tai mot vj tri co dinh (phdng thi nghiem). Mau phan tich lay ve phong thi nghiem se gay ra nhieu khd khan cho ngddi sd dung: Ldpng mau phai Idn; qua trinh thay mau se mat nhieu thdi gian va cdng sdc, gay bui ban lam mat ve sinh mdi trudng;... Viec phan tich nhieu mau nham danh gia tot hon chat lupng dong than ciing nhUxae djnh chat iL/ang md than se khd thuc hien, mau Idn se lam tang gia thanh l^y mau, tang gia thanh van chuyen t d kho/ bai tap ket than ve nai phan tich, do do se gay tam ly khdng muon sd dung thiet bj ddi vdi ngudi van hanh va khach hang.
De khac phuc tinh trang nay, cac tac giei dUa ra y tudng dat toan bd cau hinh thiing do va hop chda nguon len tren xe tai nhe hoac Ke ban tai. Tat nhien la cd sd thiet ke lai cho phii hpp va hoan cai ie thanh mdt bp phan cCia he do (hinh 6). Tren cac khe trudng loac tai cac bai than cua nha may sang tuyen than, than cd the '-dt tnic tiep t d bang truyen, t d glutei hoac tdmay xuc vao thiing 30, sau khi ket thuc qua trinh do, ngddi van hanh thuc hien md
*:ua xa d dudi day thiing la cd the dd het than ra khdi thiing do,
•hay mau mdi va qua trinh do lai tiep tuc. Viec cO ddng den vi tri '<haccungratde dang nhdsudi chuyen ciia xe.
'' Md rpng chdc nang phan tich nguyen td; Phat trien td mdt '"rhdc nang phan tich dd tro them cac chdc nang khac nhu phan 'ich ham lupng nguyen to hoac tinh ham luong cac dxit trong fmau phan tich [3,4,5]. Td pho nang luong cao cua mau phan ich thu duoc (hinh 5), co the thay mot sd viing dinh nang hifpng xuat hien kha rd rang. Bang toan hoc, cd the phan tich ac viing pho theo sU ddng gdp cac vach pho ciia cac nguyen ,.d de tinh dUpc ty le % cua nguyen to dd trong mau phan tich.
Jiat khac, neu sd dung ngudn notron vdi thdng Idong cao hon ung lam tang kha nang nhan dien va dp chinh xac cua phep ihan tich nguyen td.
flnh 6 - Aid hinh he phdn tich PGNAiA thdnh hi do hiin trudng
^a id dung xe tdi nhe (hinh cd tfnh chdt mmh hog)
* Phan tich dp am:Thiet bi PGNAA phan tich dp tro than, ngoai kha nang cd the xac dinh ham Idpng cac dxit con cd the che tao md rpng them chdc nang xac dmh do am trong than.
* Md rdng them doi tdpng do. Td phan tich than, xay dung quy trinh phan tich cho cac loai ddi tuong khac nhudat, da, quang bdxit,... Thiet bj nay iirig dung kiem tra chat luong nguyen vat lieu dau vao va s^n pham dau ra trong tdng cdng doan cdng nghe san xuat xi mang va dng dung de xac dinh thanh phan kim loai trong tham do, khai thac khoang san [4,6].
* Chuyen doi thiet bi td phan tich dong (bulk analyser) thanh thiet bj phan tich online. Sau khi hoan thien cac ky thuat tren, viec md rpng chdc nang phan tich on line, tdc la phan tich vat lieu tren cac bang tai dang chay.
* Sddung ong phat/may phat natron thay the ngudn dong vj phdng xa phat natron. Hien nay, do cdng nghe che tao cac loai may phat/ dng phat natron cdn d mdc dp han che nhutudi thp ngan, do ben thap, gia thanh che tao cdn cao, cd it cong ty tham gia che tao, hon nda thi trudng sddung loai linh kien nay chua thuc su nhieu cho nen gia thanh che lao thiet bi PGNAA sddung may phat/dng phat notron cao hon nhieu loai thiet bj PGNAA sddung nguon ddng vj. Dd la nhdng ly do ma he thiet bj PGNAA ndi chung va thiet bj PGNAA sd dung nguon phat la ong phat/may phat notron ndi rieng chda cd dUpc vj tri xdng dang tren thi trUdng cdng nghe trong ITnh vuc dng dyng ky thuat hat nhan.
Ket luan
De tai da xay ddng thanh cdng he thiet bj phan tich dd tro than sddung ky thuat PGNAA vdi ngudn phat notron la ngudn dong vi Cf-252. Vien Khoa hoc va Ky thuat Hat nhan, Trung tam trinh dien Viing (TDC - Ha Ndi) da cd them mot thiet bi phan tich hat nhan hien dai phye vu rat tot cho cdng tac dao tao chuyen sau, chuyen giao cdng nghe va tien hanh cac nghien cdu khoa hpc cd lien quan den ky thuat phan tich PGNAA.
Tiep tyc nghien cdu hoan thien ehde nang de phat trien dng dyng cua ky thuat PGNAA, thdi gian tdi, Vien Khoa hoc va Ky thuat Hat nhan se cd duoc thiet bj phan tich dudi dang cac san pham thuong mai phye vu tdt cho cdng tae tham dd, khai thac, che bien than va khoang san d Viet Nam. Cac thiet bj dUoc che tao trong nUdc se lam cho gia thanh thiet bj thap hon rat nhieu so vdi nhap khau, hoan toan chu ddng trong viec chuyen giao cdng nghe, bao tri, sda chda va md rdng chdc nang do cho thiet bl de phue vu san xuat - kmh doanh.
Vien Khoa hpc va ky thuat Hat nhan hy vpng nhan duoc su quan tam hop tac dau tu, tU van nhSm tdi du chdc nang eua thiet bi va dng dyng thiet bi cCia cac dan vi trong nganh Than va Khoang san Viet Nam de viec dng dung nang lupng nguyen t d vi mue dieh hda binh trd nen da dang va thanh cdng trong nganh edng nghiep quan trong cua Viet Nam, phuc vu d k ldc cho qua trinh edng nghiep hda - hien dai hda dat nude.
N A N C L U O N G VIET NAM So 101
