Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd" BAN V^ H$ S6 THU H 6 | DAU VA GlAl PHAP N A N G CAO B A N G BOM ep NL/CJC 061VCJI THAN DAU TRONG DA MONG TRL/CJC KAINOZOI NOT N^ HANG H 6 C M 6[.]
Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd" BAN V^ H$ S6 THU H | DAU V A GlAl PHAP N A N G C A O B A N G B O M ep NL/CJC 061VCJI THAN DAU TRONG DA MONG TRL/CJC KAINOZOI NOT N^-HANG H C M BACH H Hoang Van Quy, Truang Cong Tai, Pham Anh Tuan XNLD Vietsovpetro ABSTRACT in this section the author gives some opinions about oil recover/ from fractured basement in Bach Ho oilfield This parameter is changed rather complicatedly, not only depending on the heterogeneity of resen/oir permeability, the charactehstics of tlie fracture distribution in the basement, the water and oil viscosity, but also on the water injection system Water injection is the most effective and practical method for maximizing oil recovery from resen/oirs especiall from fractured basement Water injection method is based on the warrenty for respectively stable movement of W.O.C The stabilization of the W.O.C movement depends on the resen/oir permeability, the water and oil viscosity and the overpressure applied for injection In general, the exceeding of the hydrodinamic gradient over the gravitational gradient is a common condition for stable movement of W C Than dau mdng hang hde va nut ne, md vdi chieu day tren dudi 1500m, dac trung bdi hang loat gie'ng khoan ty phun cho nhung ddng dau khdng lin nude vdi luu lugng tren dugi mdt ngan met khdi dem, da trd mdt than diu dac biet hiem ed tren the gidi Tdng tru lugng dia chit ban diu, bao gdm CI + C2, dugc HOXDTLKS Nha nude phe duyet tdi thdi diem 1.1.2002 len tdi gin nam tram trieu tin Hien day la mdt than diu Idn nhit tren them luc dia nude ta Chinh vi vay viec tim kiem nhung giai phap ed hieu qua nhim nang cao he sd thu hdi diu (THD) dac biet cho than dau mdng md Bach Hd la vin de quan trpng va cd y nghla to Idn I Hes6THUH6lDAU He sd thu hdi d i u la mdt thdng sd dac biet ddi vdi than dau da hang hde va nCrt ne Nd phu thudc khdng nhung vao muc dp bit ddng nhat tinh chit thim ehUa, dac diem phan bd khdng gian Id hdng, dp nhdt cua dau va cac dac trung thuy dpng hpc khae cua da Trong bang dua mpt sd vi du ve he sd THD cua mdt sd md dau da nCrt ne va hang hde tren the gidi He sd dao ddng tU 0,200 den 0,660 phan anh tinh chit kha phUe tap cua nd Ham phan bd he sd thu hdi dau ddi vdi mpt than dau nhit dinh la ket qua cua phep tich chap ham phan bd cua he sd day diu bdi nude vdi ham phan bd cua he sd quet Vdi muc dich ehinh xac hda he sd THD cho than diu mdng trudc tien chung tdi tien hanh nghien cuu dac trung bien ddi he sd day d i u bdi nude bam ep cung nhu he sd diu du Ket qua thi nghiem Vien NCKH &TK d i u bien thudc XNLD Vietsovpetro cho thiy he sd day d i u bdi nude dat gia tri cao nhit trudng hgp bam tU dugi len va nguge lai thip nhit trugng hgp bam tU tren xudng Sd dl ed hien tugng la lye trpng trugng trye tiep tham gia vao qua trinh day d i u bang nuge He sd day dau va he sd dau du bien ddi kha phUe tap phu thupe vao kich thudc va dac diem phan bd khdng gian 16 hdng Chinh vi vay chung khdng the tinh chung cho toan than dau ma dupe tinh trung binh theo tUng vung va tUng lat eat rieng biet Mdi dan vi the tich dac trung bdi ty le khae phan da nUt ne Idn va phin da vi nUt ne Theo ket qua nghien cUu phdng thi nghiem ddi da nut ne Idn cd he sd day d i u trung binh la 0,650 Ddi vdi ddi da vi nUt ne tham sd la ham eua dd rdng He sd day diu cho tUng dan vi the tich Kdd dugc xac dinh theo edng thUe: Trong dd: K^^,, va d„,3,,,, K„,^, va d^,^, - he sd day dau va ty phin cua da nUt ne Idn, nut ne nhd 95 Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Ho' o o M CM LO • c ro m •TO SE c ro JC Q U •ro O o o •ro c :92 Ic c CD CD in 00 CO in 5- CD cn CO CD CD CO CD CO CM CD CD CSJ CD CD o CO CO CD CO in CD CM CD CD CD CD CD" CD" CD" -^ ^^ -^ LO CD -^ CD" CO CM cn a ãro ãô;1- CO CD CO CD CD CD" CD" o" CD" CD" o" E -re ro b 0> cn CD ro -Q ro O CD CD O o ^ » (/i E ro ro _ •v-' E ro ^^ o > CD to O XI CO CD >• o t/5 O CD Q > o CD ro O •ro w > E CD m Mar O nyd >, :eii CD tsl ro a ro Q o Hdi thdo khoa hoc "Ndng cao he sd thu hdi ddu md Bach Hd " Ket qua tinh toan cho thiy he sd day diu tU 0,100 den 0,619 cd xu the giam din theo chieu sau (Hinh 1), trung binh cho toan than dau la 0,549 tuang Ung he sd bao hda dau du la 0,384 Tuy nhien khdng the ed mpt sd nhat trung binh nao cua he sd day diu dac trung cho toan than diu Chung ehi ed the dupe phan bd theo mpt dai, mdt ham nhit dinh nao dd Tren Hinh sd trinh bay phan bd eua he sd day dau, tinh sa bp, cho than diu mdng nUt ne hang hoc md Bach Hd Tinh toan he sd quet hay bao trum, dac biet ddi vdi da mdng nCrt ne va hang hde cd mUc dp bit ddng nhat cao, la mdt vin de kha khd khan va phuc tap, ddng thdi khdng phai luc nao cung cho ket qua nhit Tren Hinh ve sd dua mdi quan he giua he sd bao trum cue da mdng nCrt ne va hang hoc thupe than dau ky phin mupn cua md dau Malgobee - Voznhexensko - Aliurtov [3] vdi muc dp bao hPa nude cua da chua ddi bam ep TU hinh ve tren cho thiy qua trinh bam ep vao ddi bao hda nude du, he sd bao trum khong vugt qua 0,55 Neu bam ep vao ddi hoan toan ngap nude thi he sd cd the dat tdi 0,93 Dudng cong quan he cd dang phuang trinh sau: 1^1 =-4*Hr*5- + + 0.0096.S' +0.368 Hinh Thay ddi he sd day dau bdi nude bam ep theo chieu sau ddi vdi than dau da mdng Bach Hd Hinh Bieu dd phan bd he sd day dau cua than dau da mdng trudc Kainozoi md Bach Hd, tinh tren ca sd du lieu bao cao "Chinh xac hoa sa dd cdng nghe khai thac va xay dyng md Bach Hd" va phu luc "Bien luan va cac giai phap nang cao he sd thu hdi dau" 1998 Trong dd: S„ - dd bao hda nude tinh bang % Neu nhu chip nhan he sd bao hoa nude du (Swr) va he sd bao hda diu du eua than diu mdng md Bach Hd la 15% va 38,4% se thu dugc gia tri trung binh cua he sd bao trum bang phuang phap giai tich phan theo phuang tnnh tren f^,, = ^ _^ Swr ^ \{- * 10-^ * S; + 0.00965,, + 0.368)/5„ = 0.67 Trong dd: S^ la dp bao hoa nude eye dai cua than diu ed gia tri 61,6% 97 Hdi thdo khoa hoc "Ndng cao he sd thu hdi ddu nui Bach Ho" Hinh Mdi quan he giua he sd quet va dp bao hPa nude cua da chUa ddi bam ep (than dau ky phin mupn cua md dau Mangobeg - Voznhesensko - Aliurtov) Theo Hinh ve sd va tren thyc te bdm ep nude tai md Bach Hd chung tdi de xuit cac gia tri cua he sd bao trum cd phan bd nhu tren Hinh ve sd Phan bd edn mang tinh lac quan cao bdi than dau cd mCrc dp bit ddng nhit theo dp thim dac biet Idn Dp thim dao dpng tU vai millidarey den hang ngan millidarey Tich chap hai ham phan bd tren Hinh sd va Hinh sd ta dugc phan bd cua he sd thu hdi diu dao dpng tU 0,20 vdi xac suit la 0,078 den 0,50 vdi xac suit la 0,18 Xac suit cao nhit cua phan bd da dugc dieu ehinh theo phan bd chuan tuang Crng vdi he sd THD la 0,372 (Hinh sd5) He sd thu hdi dau xac dinh theo ket qua tinh toan eua cac phuang an khai thac cd gia tri khdng khae biet xa he sd THD thu dugc bing phuang phap tren Viec tinh toan khai thac dugc tien hanh theo phuang an ehinh Cac phuang an khae biet bdi sd lugng gie'ng, nhip dp thu hdi va khdi luang nude bam ep He sd thu hdi eae phuang an 1, 2, la 0,367; 0,369; 0,376 tuang Ung [1] II, BI$N PHAP BOM tP Nl/CJC NHAM NANG CAO HE S6 THU H6I DAU v i n de nang cao he sd thu hdi diu la vin de dac biet quan trpng, cd y nghla to Idn viec nang cao hieu qua khai thac md Mdt sd lugng ign dau khdng liy len dugc cdn lai long dat la ddi tugng quan trpng dPi hdi ap dung cac giai phap khae nham nang cao he sdthu hdi dau Hinh Bieu dd phan bd he sd bao trum xay dyng tren ca sd md dau Magobec-Voznhexenko-Aliurtov va thyc trang bam ep tai md Bach Hd TU ket qua nghien cuu va hoat dpng thyc tien tinh vyc khai thac cac md dau tren the gidi da ed nhieu giai phap khae duac ap dung nham nang cao he sd thu hdi dau phi) hgp vgi tUng dieu kien dia chit kinh te - edng nghe neng biet Tuy nhien pham vi bao cao chung tdi xin phep chi de cap den phuang phap bam ep nude - mdt phuang phap hieu qua va thyc te nhit, dang dugc ap dung khdng nhung dieu kien than diu da mong md Bach Ho, ma cdn the hien rit rd Bang sd TU bang ta thiy sd 19 md thi cd 15 md duac ap dung phuang phap bam ep nude, nang he sd thu hdi dau tU 0,13 len tdi 0,66, trung binh la 0,41, ehi ed md dugc ap dung bam ep CO^, md bam ep - propan - nude, md bam ep nude - va md ap dung phuang phap thay ddi ddng thim, Nhu vay rd rang phuang phap bam ep nude la mdt phUdng phap phd thdng, de ap dung nhit dam bao gia tang he sd THD trung binh len 1,96 lan 98 Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd" Nhu tren chung ta da biet ham phan bd he sd thu hdi diu la tich chap ham phan bd he sd day dau va ham phan bd he sd bao trum Cho nen cac giai phap nhim nang cao he sd THD phai bao gdm eae phuang phap nang cao he sd day diu va he sd bao trum qua trinh bam ep nude Cac bien phap nang cao he sd bao trum va he sd day diu la cac giai phap dam bao mUe dp dn dinh cho qua trinh dich chuyen mat tiep xuc dau nude Khi qua trinh day diu bing nude khdng dugc dn dinh se xuat hien hien tugng kich ddng ranh gidi phan tach pha Hien tugng kich ddng cang gia tang va lan toa theo ca khdng gian va thdi gian Nguge lai day dau bang nude trang thai dn dinh sy kich dpng ranh gidi pha bien mit Cho nen cac ddng thim Ipe dich chuyen khdng dn dinh cd the din den nude tran vao gie'ng khoan, lam thip he sd bao trum, he sd day diu va eudi cung la he sd thu hdi diu Op dn dinh dich chuyen ranh gidi daunude phu thudc vao tinh chit thim Ipe eua da chua, dp nhdt, mat dp diu via va nude bam ep dupe xac dinh bdi dp chenh ap giua diem hut dau len va diem bam nude vao MUe dp khai thac va bam ep cang nhieu, mUc dp chenh ap cang Idn va vay xac suit tao ludi nude tran vao gie'ng khoan cang nhieu K„M, H K, M (2) / i J _ :':'''• o' '^'^.i i^vMlHi i ' i 1 j^ K33i , j J60 I I •^H 0D30 :• 70 i.90 i -.-i \ J V ! r i ; i j j : ' 4,, -• ••MHHHIHIIHHi^BUif ^t^KS^K^KK/UKKM i ^^^H^BSBwwl? I 1( i „ U- - r(, ! -4— - • ! -— — ( - - j \ 1 i AP ' j 40 i (1) Si = Yw • Yo —'.—1~- Dieu kien tdng quat dam bao cho mat ranh gidi dau nude dich chuyen dn dinh dieu kieu ddng chat luu thim khdng ddng nhit la sy khdng vugt trpi cua gradient thuy ddng lye ddi vdi gradient trpng trudng Gradient trpng trudng 81, va gradient thuy dpng lye 62 dugc tinh theo cdng thUe sau day: Hinh Bieu dd phan bd he sd thu hdi dau eua than diu da mdng trudc Kainozoi md Bach Hd, tinh tren ca sd bleu dd phan bd udc dinh he sd bao trum K n p / lC np -40 Hinh Danh gia trang thai bom ep cua gieng khoan bam ep md Bach Hd Sy dich chuyen cua nude bam ep (sd dudng cong-chenh ap MPa/km) hy- Gradient trpng trudng, 62- Gradient thuy dpng lye 1- Odi xuat hien ludi nude, 2- Odi dich chuyen dn djnh dieu kien chenh ap cd dinh, 3- Ddi bao dam djch chuyen dn dinh lien tuc (ap dung dieu kien than diu da mdng md Bach Hd - theo Hoang Van Quy) 99 Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bach Ho" Trong dd: YW K' MW va YQ, KQ , MQ - ty trpng, dp thim, dp nhdt cua nude va diu tUdng Crng YW YO tinh bang MPa/km, DP-MPa, H-km Tren Hinh bleu thi mdi quan he qua lai giua gradient thuy ddng lye vdi cac gia tri dp tham tuang ddi (KJKo) khae TU hinh ve ndi tren rd rang de bao dam mCre dp dn dinh dich chuyen ranh gidi diu - nude can han che gradient thuy ddng lye cho nd ludn nhd han gradient trpng trudng Do dp nhdt cua diu da mdng md Bach Ho thip, trudng hgp dp thim tuang ddi khdng vugt qua 0,52, dn dinh dich chuyen ranh gidi diu - nude ludn dugc dam bao vdi mCre chenh ap thay ddi Idn (vung 3) vung dp dn dinh dich chuyen ranh gidi diu - nude dugc dam bao gradient thuy ddng lye ludn nhd han gradient trpng trudng Vung la vung pha vd sy dn dinh dich chuyen cua mat ranh gidi diu nude Trong qua trinh dieu chinh khai thac, dac biet ddi vdi cac md ngoai bien cin dat nhip dp san lugng khai thac va bam ep du Idn din tdi hien tugng mau thuin giua nhip dp khai thac va dieu kien dn dinh dich chuyen mat ranh gidi dau nude cho tUng khu vyc rieng biet cua than dau hay toan md Vdi muc dich han che kha nang hinh "ludi nude" ta phai ludn dam bao cho gradient thuy ddng lye khdng vugt trpi gradient trpng trudng Dieu kien la mdt bUe rao can Idn nhit cho viec tri hoae nang cao nhip dp san lugng khai thac De khae phuc mau thuin can thie't xem xet, nghien eCru va ap dung phuang phap bam ep theo chu ky va tang quy gie'ng khoan bam ep Ca sd de xuit phuang phap bdm ep theo chu ky, bao gdm ca ngUng hoae giam luu lugng bdm theo thdi gian, la tao cho gia tri gradient thuy ddng lye tren hinh ve ludn dao ddng xung quanh dudng tdi han cua vung va Tren Hinh trinh bay ket qua xac dinh mCre dp dn dinh dich chuyen mat ranh gidi diu nude vao 0409-2002 d khu vyc eae gie'ng khoan bam ep 911, 921, 914, 484, 464, 433, 435, 455 va 437 TU Hinh ta thiy sd nhung gie'ng khoan tren chied gie'ng khoan 911, 921 va 914 la nim d vung 3- vung dam bao an toan sy dich chuyen Trong lat cat mdng trudc Kainozoi cua nhung gieng khoan tren khdng phat hien thiy nhung khoang nCrt ne cd dp thim Idn han 150 mD hay dp thim tuang ddi nudc/diu Idn han 0,52 Ddi vdi nhumg gieng khoan ap suit nen qua trinh bam ep khdng cin phai gidi han tren khia canh dam bao dp dn dinh dich chuyen mat ranh gidi dau nude Cac gie'ng khoan 464,455,435,484,433, 437 vao thdi diem deu nam d ddi pha vd mat ranh gidi diu nude (PGDN) va tao ludi nude tien vao khu vyc cac gie'ng khai thac Vi du GK 433, 23-09 -2002 bam ep vdi ap suit mieng gieng la 205 at Tai dp sau 4000 m, ap lye cpt nude dat tdi 605at, gradident thuy ddng lye tuang Ung 82,76 MPa/km , vugt trpi qua nhieu so vdi gradident trpng trudng la 3,12 MPa/km Vdi ap lye 605 at nude bam ep se bd qua toan bd he thdng nUt ne nhd ma tap trung di vao cac ddi nCrt Idn cd dp tham dat tdi hang ngan millidariy Vdi muc dich tang he sd bao trum, ddng thdi giam mCre dp chenh ap DP giua dudng khai thac va dudng bdm ep cung nhu tang chenh lech dp sau giQa hai dudng tren (edng thCre 2) ddi hdi phai bd tri eae khoang bdm ep vao vung ngap nude 100% dudi dp sau tuyet ddi - 4000m Do tinh tham chCra cua da cd mCre dp bat ddng nhat rit cao nen cd the ap dung phuang phap dieu chinh ddng thim Ipe bang cac nut hda hpc Phuang phap da dugc nghien cuu d phdng thi nghiem cua Vien NCKH & TK va dugc thCr nghiem dieu kien cua md Bach Hd d dang dung hdn hgp vd cd tao keo eua "GALKA" va hgp chat thuy - keo kim loai hda tri Tren ca sd nhung luan diem ndi tren, de nang cao he sd thu hdi dau ma cu the la he sd bao trum va he sd day diu bang nude, chung tdi de xuat ap dung mdt sd giai phap sau day: 100 Xem xet bo tri eae gieng khoan bam ep theo chum va bam vao phan dudi ngap nude eua than diu tro mdng Phan bd gie'ng khoan theo sd dd 5, gie'ng tuang ty cho da cd dp rdng giua hat khdng hoan toan phu hgp vdi muc dich nang cao he sd THD ddi vdi da mdng nCrt ne va hang hoc Dieu chinh ap suit day eua mdi gieng bdm ep va khai thac theo thdi gian, thudc vao dp day eua cac khoang nut ne cung nhu dp tham cua chung cho cd the kiem tra dugc muc dp vugt trpi cho Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bach Hd" phep cua gradient thuy ddng lye so vdi gradient trpng lye Can thiet ap dung bam ep theo chu ky bao gom ca ngung hoae giam luu lugng bom theo thdi gian, dac biet doi vdi phan co tham qua lan Do tham tai han dam bao su dich chuyen ludn on dinh nude bam ep dieu kien than dau mdng mo Bach Ho la 150mD De dam bao thyc hien cac giai phap de xuit thCr kien nghi nghien eCru bd sung quy gieng bam ep phu hgp Tang eugng khai thac cac phan eua than diu, nai thiy cd hien tugng sdt tdn lai tru lugng va cham dich chuyen ranh gidi diu nude, tang sy bu dap cho nhung vung cd di thudng ap suit thip Phan bd hgp ly khdi lugng khai thac va bam ep, han che bat luu lugng cua cac gieng khai thac va mere tiep nhan cua gieng bam ep, ke ca ngung hoat dong eua chung ddi vdi mpt sd gieng khoan phat hien thiy hien tugng tao " ludi nude" Dich chuyen tuan ty cac khoang khai thac tU dudi len tren d eae gieng khai thac da mdng Do d phan tren cua than dau da mdng mat dp khe nut cd dp thim tdt tang len rd ret, nen kha nang tao "ludi nude" cang cao Cho nen chuyen cac khoang bam ep len phin tren can xem xet kha nang ap dung cac hda chit nham tang dp nhdt cua nude bam ep hoae cac nut hda hpc nham dieu ehinh ddng thim qua Idn TAI Lieu THAM KHAO Tran Le Ddng, Hoang Van Quy, Truang Cdng Tai, Pham Anh Tuan va nnk "Hoan thien sd dd cdng nghe khai thac va xay dyng mo Bach Hd" Vietsovpetro, 1998 Trin Le Dong, Hoang Van Quy, Truang Cdng Tai, Pham Anh Tuan va nnk "Bien luan he sd thu hdi dau va cac giai phap chu yeu nang cao he sd dd" Vietsovpetro, 1998 N P Lebedinhes Nghien cuu va khai thac cac md diu da chCra nUt ne Moskva, "Nauka", 1997 101 ... dp thu hdi va khdi luang nude bam ep He sd thu hdi eae phuang an 1, 2, la 0,367; 0,369; 0,376 tuang Ung [1] II, BI$N PHAP BOM tP Nl/CJC NHAM NANG CAO HE S6 THU H6I DAU v i n de nang cao he sd thu. .. Kainozoi md Bach Hd, tinh tren ca sd du lieu bao cao "Chinh xac hoa sa dd cdng nghe khai thac va xay dyng md Bach Hd" va phu luc "Bien luan va cac giai phap nang cao he sd thu hdi dau" 1998 Trong. .. cao he sdthu hdi ddu md Bqch Hd" Nhu tren chung ta da biet ham phan bd he sd thu hdi diu la tich chap ham phan bd he sd day dau va ham phan bd he sd bao trum Cho nen cac giai phap nhim nang cao