792 Nghien ciiu iing dung kigu he dung djch Packer gdc nuoc tgng trongj^ojLJH NGHIEN c t r u iTNG DUNG KIEU HE DUNG DICH PECKER GOC NU^OC TANG TRONG HOA TAN Nguyin van Ngg Cdng 0'''' DMC D6 Thanh Bai Vie[.]
792 Nghien ciiu iing dung kigu he dung djch Packer gdc nuoc tgng trongj^ojLJH- NGHIEN c t r u iTNG DUNG KIEU HE DUNG DICH P E C K E R G O C NU^OC TANG T R O N G H O A T A N Nguyin van Ngg Cdng 0' DMC D6 Thanh Bai Vien Hod hpc Cdng nghiep TOMTAT Trong khudn khd bdi ndy, chung tdi xin md td nhirng dge diim chung nhdt ve dung dich packer, thdnh phdn diin hinh cita kiiu hi dung dich packer gdc nu&c tdng trgng hod tan, phdn tich nhirng diim ddc bid cdn luu y thiit ki, sir dung logi hi dung dich theo kiiu hi ndy Dung dich packer la ten ggi eiia mgt loai dung dich duge sir dung khoan, khai thac dau Ten ggi kh6ng xuat phat tir chirc nang, tinh nang c6ng nghe cua loai dung dich, ma xuat phat tir ten ggi vi tri thiet bi ciia no gieng khoan Loai dung dieh bao g6m nhieu kieu he, nhieu he kbac Cum thuat ngii "dung dich packer" dimg de ehi chat I6ng dugc luu lai khoang kh6ng gian vanh xuyen gitra can khai thac va 6ng eh6ng khai thac phia tren vi tri dat packer Trong gieng bom ep, dung dich packer luu khoang kh6ng gian vanh xuyen giira can bom ep va 6ng ch6ng khai thac phia tren packer (Hinh 1) Gan nghTa voi cum thuat ngir "dung dieh packer" co "dung dieh vanh xuyin" Dung dich vanh xuyin la dung djch khoang kh6ng gian vanh xuyen gitra cac cot 6ng ching hoae gitra cot Ing eh6ng va he gieng khoan Dung dich packer co ba chirc nang c6ng nghe chinh sau: Giam miic chenh ap gitra phia va phia ngoai can khai thac gilng khai thae, can bom ep gieng bom ep (vi tri chir A Hinh 1), nham tranh cho can khbi hien tugng bien dang hoae vo; - Giam mirc chenh ap gitra va ngoai Ing chong khai thae (vi tri chir B Hinh 1), nham tranh hien tugng b6p meo Ing ch6ng khai thae; Giam mire chenh ap gitra phia tren va phia duoi packer (vi tri chii C Hinh 1), nham giam nhe luc can thiet de e6 dinh packer [1-5] Nhu vay, ve thuc chat dung dich packer la chat I6ng thuy luc co nhiem vu tao cot ap thuy tTnh ep len mat ngoai can khai thac, mat Ing eh6ng khai thac va mat phia tren ciia packer Tuy nhien, viec tao phan ap kh6ng nham can bang tuyet d6i voi cac ap suat thuan va neu co mu6n ciing kh6ng dat duge, hoae kh6ng can thiet phai dat toi Chang ban, neu thiet kl dl ap suit va phan ap phan duoi can khai thac can bang thi phan tren dieu kien lai kh6ng dat dugc (tiln len phan tren can khai thae, ap suat thiiy tTnh ciia dung dich packer triet tieu dan c6n ap suat ben can phu thuoc vao ap suat mieng Tuygn tap bao cao Hoi nghj KHCN "30 nam Phu Viet Nam: Co' hoi mdi, thach thiic moi' 793 gilng); nlu thilt kl dl ap suat va phan ap phan duoi ong ch6ng khai thae can bang thi a khoang tren lai kh6ng can thilt vi no dugc cap Ing ch6ng khae bao ve San phdm khai thac can khai thac-NKT /Mat d^t S JS a M i F-F Ong chdng khai thac T c Q Ong chdng khai thac can khai thac-NKT KhCng gian vanh xuyei chiia dung dich Packer Hinh 1: So' mo ta dung djch packer gieng khoan De thuc hien dugc chuc nang e6ng nghe eiia minh, dung dieh packer can eo nhiing tinh nang c6ng nghe nhat dinh Nhtrng tinh nang co the la tinh nang can thiet (tinh nang xuat phat tir chirc nang chinh), co the la tinh nang mong mu6n (tinh nang phat sinh thuc hien chiic nang chinh hoae duge dat tir nhung yeu cau c6ng nghe khae) De dam bao chirc nang cong nghe chinh, dung dich packer can co ty trgng hgp ly va on dinh theo thoi gian dieu kien thuc te cua gieng khoan (chieu sau, quy dao, ap suat, nhiet do, v.v.); tao dieu kien thuan lgi cho kiem soat tinh trang gieng khoan tien hanh cae khau c6ng nghe kbac hoae xay su c6 Trong s6 tinh nang phat sinh tir viec thuc hien chire nang chinh can phai ke toi nhu: tinh nang ban che hien tugng an mon mat ngoai can khai thae, mat 6ng chong khai thac, mat tren packer; tinh nang ban che sa lang pha ran xu6ng mat tren packer; tinh nang ban che tac hai ciia su c6 ro ri co nguyen nhan tir via chira, v.v Khi diing dau (dau diezen, dau th6 da tach parafin, tach khi, tach nuoc, dau tong hgp khong chira pha nuoc, v.v.) lam dung dich packer, thi tinh nang ban cbl an mon kh6ng can dat Khi kh6ng cin tang ty trgng dung dich cao hon ty chat I6ng hoae sir dung chat tang trgng la mu6i boa tan (NaCI, CaClj, KCI, COOHNa, v.v ) thi hien tugng sa lang pha ran xulng mat tren packer cung kh6ng c6n la vhn dk chn tinh din 794 Nghi6n ciru iing dung kigu h^ dung djch Packer g6c nuoc tang trpngjToaJaii^ Nh6m tinh nang thii ba ciia dung dich packer la nhom tinh din yeu cau ve c6ng nghe khai thae, yeu cau ve an toan m6i truong cang cao va khia canh kinh tl ciia ap dung nhu: Han cbl nhiem ban via san pham (khi thay dung dich, tiln hanh sira chira gilng, hoae xay su c6, v.v.); - Cho phep khoi dgng lai tuan hoan mgt each dl dang cin thilt (khi sira gieng, ggi dong lai, v.v.); De dang chuyen d6i muc dich sir dung (chuyen d6i tir dung dich hoan thien gilng sang, tan dung lai lam dung dich sira gieng, v.v.); Co kha nang bit nhet khe ro ri tren 6ng ch6ng; De pha che, dieu chinh; it gay dge hai, mat an toan cho nguoi sir dung; v.v Nhu dugc nhac toi phan tren, dung dich packer bao gom nhieu kieu he va nhieu he Khi noi toi kieu he ta hieu la nhom he co chung mgt hoae mgt vai dac diem dac trung, n6i toi he ta hieu la mgt he dung dich cu the voi dac trung ve chat va ve lugng ciia cae cau tir phan Cae c6ng ty dich vu dung dich khoan kbac co the co chung mot, hoae mot vai kieu he, nhung chung lai thuong co nhiing he dung dich packer rieng voi phan cu the ve lugng va ve chat cua boa pham sir dung Cac hang co the the gitr ban quyen ve he dung dich packer cua minh Cho toi thoi diem hien tai, chiing t6i chua tim dugc tai lieu nao dua phan loai cac kieu he dung dich packer Tuy nhien, theo chiing toi, ta CO the phan biet kieu he dung dich packer theo mgt s6 dac trung chung cua chiing Chang ban, can cii vao dung m6i hoae moi truong phan tan ta co the phan chiing thanh: kieu he g6e nuoc (eae he diing nuoc ky thuat, nuoc bien, nuoc mu6i; dung dich set, dung dich polyme, v.v ) va kieu he goc dau (cac he dimg dau diezen, dau th6 da tach va parafin, dau t6ng hgp, nhii tuong nguge, v.v ) Can cii vao su co mat ciia pha ran phan, dung dich packer c6 the dugc phan thanh: kieu kh6ng chira pha ran (cac he dung dich polyme phi set, he chi gom mgt cau tir la nuoc bien, nuoc ky thuat, kieu he tang boa tan; va kieu he co ehiia pha ran (dung dich set, dung dich khoan tach phan pha ran co kich thuoc Ion, v.v.) Can cii vao ban chat chat tang trgng, ta co the phan biet cac kilu he nhu: kieu tang trgng hoa tan (dung dich muli hoa tri I: NH4CI, KCI, NaCI, COOHNa, NaBr, COOHK, COOHCs; dung dich mu6i hoa tn II: CaCIj, MgCIz, CaBrj, ZnBr2, v.v ); va kieu he tang trgng khong hoa tan (cac he c6 dimg chat tang trgng CaC03, barit, v.v.) Kieu he dung dich goc dhu, hoae vi ly an toan chay n6, nhiem m6i truong (nhu cac he dimg dau diezen, dau th6 da tach va parafin, v.v ) hoae vi ly kinh te (cac he diing dau tong hgp thuong rat dat), cang it dugc diing thuc te Viec sir dung dung dich co chira pha ran kh6ng hoa tan (dung dich set, dung dich khoan co ehiia pha ran, v.v ) la viec xay nhilu thap ky truoc Trong b6i canh tien bg nhanh ciia khoa hgc c6ng nghe va yeu chu phat triln bin viing, kilu he dung dich packer g6c nuoc kh6ng chiia pha ran (kilu he tang trgng hoa tan) da va dang nhan dugc su quan tam iing dung hon ea Cung chinh vi vay, phan tilp theo duoi day, chung t6i xin m6 ta phhn kilu he Tuygn tap bao cao HQi nghj KHCN "30 nSm Dau Viet Nam: Co' hoi moi, thach thiic moi" 795 dung dich tang trgng boa tan diln hinh va nhimg dilm dac biet can luu y thilt ke, sir dung loai kieu he dung dich Thanh phhn diln hinh cua kilu he dung dich packer glc nuoc tang trgng hoa tan dugc dua Bang Bang 1: Thanh phan dien hinh cua kieu he tang hoa tan TT Chirc ndng kieu he Tin cdu tu thdnh phdn Nuoc sach, nuoc ky thuat, nuoc Dung moi bien NaCI, KCI, CaCl2, NaBr, Tang trong, tao ap suat tham thau, irc che truong no set, v.v ho trg bao ve tang san pham HCOONa, CaBr2/CaCl2, v.v Na2C03, NaOH, KOH, v.v Giam ham lugng Ca ^, Mg ^, dieu chinh pH chong an mon, hap thu H2S Chat khir oxy Giam thieu an mon tac dong ciia O2 Chat ire che an mon Uc che an mon theo co che tao mang hap phu tren be mat thep Chat diet khuan Kiem soat boat dong cua vi khuan khir sunphat Chat hap thu H2S Phong ngira an mon xuat hien H2S Chat hap thu CO2 Phong ngira an mon tac dong cua CO2 Tir Bang ta thay, cac cau tir phan kieu he dam bao cho dung dieh eo dugc ca cac tinh nang xuat phat tir chirc nang chinh, ca tinh nang phat sinh thuc hien chiic nang chinh va tinh nang xuat phat tir nhirng yeu cau c6ng nghe khae Sau day, chiing toi xin phan tich tinh khoa hgc, tinh thuc tien thiet ke kieu he va nhimg diem dac biet can tinh den nghien ciiu, thiet ke he dung dich cu the Neu chi tinh den chiic nang chinh thi kieu he dung dich tang trgng boa tan chi g6m cau tir voi chirc nang la dung m6i va chat tang trgng boa tan Ciing dung m6i la nuoc, bang each chgn loai muoi (hoae hon hgp mu6i) tan va nong mu6i hgp ly ta co dugc dung dich co ty trgng, co nhiet ket tinh dam bao cho tat ca cac c6ng doan e6ng nghe, tir pha cbl tren bl mat din dua vao vi tri lam viec va thuc hien chiic nang chinh kh6ng gian vanh xuyen gieng khoan Tuy nhien, ngoai chi tieu ve ty trgng, nhirng van de di kem can giai quyet thiet ke dung dich packer kieu g6c nuoc tang trgng hoa tan lien quan toi van de phat sinh qua trinh thuc hien chiic nang chinh, van de an mon kim loai Be mat kim loai tiep xiic voi dung dich packer thuong bi an mon dien boa vi su co mat cua O2 (tan san dung dieh hoae bi keo tir khong vao), CO2 va H2S (xam nhap vao dung dich tir via chiia hoae hinh duoi tac dgng ciia vi khu^n khir sulfat) De bao ve be mat kim loai, nhieu co che bao ve ching an m6n dugc ap dung ding thoi pH dung dich dugc chgn cho tic an mon, xac suat an mon 16 dugc giam thilu Chat khir oxy dugc diing de giam thieu an mon tac dgng cua oxy Chat lic cbl an m6n theo co cbl tao 796 Nghien ciiu iing dung kigu he dung djch Packer gdc nuoc tang trpngjioajan^ mang hap phu each ly be mat kim loai can bao ve voi m6i truong gay an mon Chat hap thu H2S, CO2 phong ngira an mon tac dong ciia H2S, CO2 Chat diet khuAn dugc diing kilu he nham kiem soat boat dgng ciia vi khuan khir sulfat vl thuc chat chinh la phong ngira su xuat hien eua H2S va CO2 (boat dong ciia vi khu^n khir sulfat sinh H2S va CO2) Cac cau tir tir -^ kieu he d6ng vai tro tao tinh nang eh6ng an m6n, tinh nang phat sinh qua trinh thuc hien chiic nang chinh ciia kilu he dung dich packer g6e nuoc tang trgng boa tan Nguoi quan tam ky hon nhung van de e6 the tham khao cae tai lieu [6-10] Nh6m tinh nang thir ba thuong dugc tinh den kieu he dung dieh tang trgng hoa tan la nhom tinh nang xuat phat tir nhiing yeu cau e6ng nghe khae, eae yeu t6 lien quan toi ehu trinh c6ng nghe thi cong, sira ehiia gieng Dung dich packer, qua trinh dua vao vi tri lam viec hoae xay su c6 voi cum thiet bi 16ng gieng, thuong xam nhap vao via san pham Neu dung dich co phan kh6ng chuan se xay nhiem ban via, gay thiet hai Ion cho khai thae dau Dung djch packer can co phan cho it gay nhiem ban via (kh6ng chira pha ran co kha nang sa lang, kh6ng chiia nhiing chat de gay lang dgng hoae bit nhet via chira; c6 chiia nhung chat c6 kha nang irc che su truong no cua khoang set he ian can gieng khoan, V.V.) Bang each ebon dung dich mu6i tan phii hgp ta co the giai quyet t6t yeu cau vira neu Cimg nhom tinh nang xuat phat tir nhtrng yeu eau c6ng nghe khae e6 eae tinh nang tinh den dac diem ciia yeu t6 cong nghe ciia c6ng doan truoc c6ng doan dua dung dieh packer vao sir dung Do la: •Theo thir tu qua trinh thi c6ng, dua gieng vao boat dgng, truoc hit nguoi ta sudung dung dieh khoan (thuong la vai ba he co tinh chuyen tilp) dl khoan toi noe via san pham, tiep den nguoi ta sir dung dung dieh hoan thien gilng dl thue hien qua trinh khoan vao via san pham, tuan hoan lam sach day gilng, lap dat thilt bi I6ng gieng (thuong la can khai thac va packer), ban via (nl due 16 qua Ing ching) Dung dich packer eo the dugc dua xulng gilng thay thi dung dich hoan thien gilng vj tri phia tren vi tri ban via truoc luc mo packer truong hgp viec ggi dong san pham kh6ng can diing toi kh6ng gian vanh xuyin - noi dung dich packer dang duge luu Dung dieh packer ciing c6 the dugc dua vao vi tri sau ggi dong san pham truong hgp viec ggi d6ng san pham can dimg toi kh6ng gian vanh xuyin (dl thuc hien viec thay the cot dung dieh hoan thien gilng can khai thac bang cot dung dich co ty trgng nh6 hon) Trong truong hgp sira chiia gieng khoan, qua trinh dua dung dich packer vao thay dung dich sira chira gieng ciing thuong xay hai truong hgp nhu vira neu tren • Trong thuc te sir dung dung dich packer, vi ly kinh te, nguofi ta thuong xuyen ap dung bien phap chuyin dii dung dich hoan thien gieng, hoae dung djch sira chtra gieng dung dich packer [2-5] Nhu vay, nhom tinh nang xuat phat tir cae ylu t6 lien quan toi chu trinh c6ng nghe thi e6ng, sira chtra gilng cho thay, can eo cac giai phap c6ng nghe thich hgp dam Tuygn tap bao cao Hdi nghj KHCN "30 nam DSu Viet Nam: Ca hdi mdi, thach thiic mdi" 797 bao cho dung dich packer (ca duge pha moi, hoae duge chuyen d6i tir cac loai dung dieh kbac sang) vao tai vi tri lam viec c6 phan diing nhu mong mu6n Khi nghien ciiu thilt kl dung dieh packer noi chung, he dung dich theo kieu tang trgng boa tan noi rieng, ngoai nhtrng dae diem chinh da phan tieh tren, chiing ta c6n can chii y dac biet toi nhung dae dilm mang tinh ngi bg chinh mgt he D6 la: • He dung dich packer la he da cau tir nen c6 yeu cau cao hon ve tinh tirong hgp cua cac co cbl dugc ap dung va su tuong hgp cua cac hoa chat dugc sir dung (phat huy hieu irng dong tac dung, ban che hieu irng lam giam tac dung cua nhau, ban che tao cac chat sa lang, v.v.) Trong thiet ke he tang trgng hoa tan cu the, chat Ore che an mon c6 the dong luon vai tro phong ngira an mon xuat hien HiS, CO2 Trong truong hgp cac cau tir thir 7, thir Bang khong t6n tai ve chat, cau tir thir lai tang ve lugng Neu chat irc che an mon c6 the dong them ca vai tro chat diet khuan thi cau tir thir cua he ciing khong ton tai Viec giam ve lugng cau tii nhu vira neu giam nhe van de lien quan toi tinh tuong hgp ciia he, giam nhe cong viec thuc thi sir dung ngoai hien truong • Phan dung dich pcker nam duoi sau phai lam viec lau dai dieu kien nhiet cao, ap suat cao nen doi hoi nhiing hoa chat dugc diing pha che dung dich packer phai ben nhiet va co hieu qua cao Tom lai, khu6n kh6 c6 ban ciia bai viet, chiing t6i da c6 gang m6 ta nhung dac diem chung nhat ve dung dich packer, phan dien hinh cua kieu he dung dich packer g6c nuoc tang trgng boa tan, phan tich nhiing diem dac biet can luu y thiet ke, sir dung dung dieh packer theo kieu he TAI LIEU THAM KHAO Engineering manual, Acho drlling fluids, 1988 Engineering manual and product data sheet M-I drilling fluids, 2000 Manual, Intemafional drilling fluid, 1995 Engineering manual, Schlumberger, 2001 Engineering manual, Baroid B.F Davis Corrosion problems in packer fluids South-western Petroleum Short Course, Department of Petroleum Engineering, Texas Tech University Packer fluids and corrosion processes, www.edelweissent.com Corrosion Mud school, M-I, 2002 H.E Bush, 1973 Controlling corrosion in petroleum drilling and in packerr fluids In Corrosion Inhibitors - National Association of Corrosion Engineers, Houston, Texas lO.Lahodny-Sarc Corrosion inhibitors in oil and gas drilling and production operations Mining, Geology and Eng Dept Univerrsity of Zagreb, Croatia ... 795 dung dich tang trgng boa tan diln hinh va nhimg dilm dac biet can luu y thilt ke, sir dung loai kieu he dung dich Thanh phhn diln hinh cua kilu he dung dich packer glc nuoc tang trgng hoa tan. .. thiet ke he dung dich cu the Neu chi tinh den chiic nang chinh thi kieu he dung dich tang trgng boa tan chi g6m cau tir voi chirc nang la dung m6i va chat tang trgng boa tan Ciing dung m6i la... nuoc, v.v.) lam dung dich packer, thi tinh nang ban cbl an mon kh6ng can dat Khi kh6ng cin tang ty trgng dung dich cao hon ty chat I6ng hoae sir dung chat tang trgng la mu6i boa tan (NaCI, CaClj,