Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bach Ho" DUY TRi AP SUAT BANG viec BOM EP NLTCJC BI^N VAO TANG M 6 N G M 6 BACH H 6 GlAl PHAP CO BAN NANG CAO wt s6 THU H 6 I DAU Tran Le Dong, Truang C[.]
Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bach Ho" DUY TRi AP viec BOM EP NLTCJC BI^N VAO T A N G M N G GlAl PHAP CO BAN NANG CAO wt s6 THU H I DAU SUAT BANG M6 BACH H - Tran Le Dong, Truang Cong Tai, Nguyen Van Ut XNLD Vietsovpetro INTRODUCTION Injection seawaterinto the bottom of basement oil resen/oir of Bach Ho field for maintaining resen/oir press is one of technological decisions, which have both scientific meaning and practical importance This decision official legality in force by approved many oil field development plans in 1993 and 1999 by Government Committ on control resource By method of oil production from basement resen/oir with maintaining resen/oir pressure, recover/ factor is higher than depletion drive from 1.5 to 2.0 times Joint Venture "Vietsovpetro" approach succ new system design, that permit thoroughly control of injected water movement, successfully production and inje management for improvement water injection efficiency - the main method for improvement oil recovery factor basement resen/oir of Bach Ho field I CO s d BOM eP NL/CJC Nhu cau tri ap suat via Ting mdng md Bach Hd dugc dua vao khai thac thang nam 1988 Den thdi diem targe bam ep da khai thac dugc gin 15 trieu tin dau, ap suit tai nde mdng giam gin den ap suit bao hda dau Tmng binh eU khai thac tneu tan diu, ap suit via giam khoang kg/em^ Than diu dugc danh gia la ddng kin, khdng ed nguon nudi Thyc te dd ddi hdi sy cin thiet phai tri ap suit via Da tien hanh xem xet cac phuang an tri ap suit via, mpt nhung phuang an kha thi dieu kien XNLD Vietsovpetro la tien hanh bam nude bien vao via Dac tinh iTa niedc va bat dong nhat cao cua da cht^a Ket qua nghien eCru m i u Idi phdng thi nghiem cho thiy, da mdng md Bach Hd cd tinh ua nude, gdc tiep xuc 43° va 108' tuang Ung cho khung da va nUt ne Ap suit mao din eua da chUa vi nUt ne kha Idn den 5,0 kg/cm^ - dieu kien thuan lgi cho qua trinh bdm ep nude Da chua cua than diu tang mdng thupe kieu hang hde nUt ne Khdng gian Id hdng rat da dang va phuc tap bao gdm eae hang hde, eae nCrt ne Idn va vi nut ne, chung lien ket vdi tao mpt mang ludi nut ne va hang hde thdng nhit (Hinh 1) Sy tdn tai mang nUt ne hang hde nhu vay dugc ghi nhan cac ket qua nghien cUu gieng khoan Mat khae, ket qua nghien eUu giao thoa cho thiy giua cac gieng khoan d khdi Trung tam ed mdi quan he thuy lye tdt (Hinh 2) 405 404 41 Macro fracture aperture: 100-500 ^m perm: den 20 D porosity: I -2 % Unchanged Rock perm » " poronity < 0-'% Micro fracture aperture.' I-10 urn perm: S-7 mD porotUy:2-l0 % 42 Hinh Md hinh da chua ting mdng 64 Hinh Lien thdng thuy lye tdt giua cac gieng Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu mo Bqch Hd" Nghien eCru bing eae phuang phap FMS va DSI eua 25 gieng khoan cho thiy ring he thdng nCrt ne phat trien rdng, nhung ed dac trung bat ddng nhat rat Idn, the hien qua mat dp, kich thudc va trudng phan bd cua chung Trong da mdng md Bach Hd tdn tai loai dp rdng chinh: Op rdng lien quan den eae nCrt ne Idn, hang hde Idn bien thien khoang 1-2% (ed dp md tU 80-100 micromet trd len chiem ty le 0,18 tdng dp rdng cua da mdng); Vi nut ne vdi dp rdng trung binh la 3-4%, ddi dat tdi 10-20%, dp thim nhd thdng thudng khdng qua 1-5mD; Khdi da nguyen sinh ran chic cd dp rdng nhd (xic wiUi iniect] on waicr diu ehinh, cd chieu cao khdng Idn lai nim kep v.tiiiilaudsaMwftontnlpioihKuia wi-ll giu'a ddi mu thU sinh va ddi bam nude, chenh ;|:^ Wmr.-.l ifid •jih-hon-miial inirrtiiirvi-.-ll ap Idn dd gay ngap nude sdm eae gieng khai thac Hinh He thdng khai thac ddi mdi d phan tren Ddi - thap han 3850 met, thyc te gan giua than diu Cac gieng duac thiet ke thang dUng Nham khae phuc nhuac diem cua he thdng khai thac cu, tU nam 1995 da trien khai edng mdt he thdng khai thac mdi gdm ddi Odi 1: Ddi khai thac (ph£n can nde); Ddi 2: Odi bam ep nude (phan can day)' Giua hai ddi la vung chuyen tiep cd vai trd dieu tiet qua trinh ngap nude ? » •• 66 Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd" Trie'n khai he thdng khai thac mdi, da khoan mdt sd gieng a ngang d phan can nde de khai thac va khoan cac gieng a ngang vao vung can day de bam ep nude Da thyc hien giai phap chuyen khoang khai thac len vung can nde, lan lugt dugc dUng eae gieng bam ep ed khoang bdm ndng va ban via phin tren de chuyen chung gieng khai thac Hien nay, he thdng khai thac mdi eua tang mdng md Bach Ho tai XNLD Vietsovpetro da hinh va tiep tue dugc hoan thien Da khoan han 100 gieng, dd ed 76 gieng khai thac va 27 gieng bam ep Luu lugng khai thac diu trung binh mdi gieng dat 465 tin/ngay, bam ep 2215 m%gay Mat khae, kiem soat chat che sy van ddng eua nude bam ep via, dieu chinh che dp edng nghe khai thac va bam ep cua eae gieng ddng mdt vai trd dang ke viec nang cao he sd thu hdi diu Che edng nghe cac gieng eua tang mdng khdng ngUng dugc dieu chinh thdng qua kinh nghiem thyc te quan ly md gin 10 nam khai thac va bam ep nude Cd the ndi rang, mpt chUng myc nao dd che cdng nghe eae gieng khai thac va bam ep dang ap dung hien da dan dat den mUe hgp ly III Hieu QUA Trong tinh toan phuc vu thiet lap Sa dd cdng nghe khai thac va xay dyng md nam 1993,1998, cac tac gia da danh gia so sanh hieu qua cua qua trinh bam ep nude vdi phuang phap khai thac bang nang lugng ty nhien Ket qua tinh toan cho thiy, he sd thu hdi dau eudi cung eua phuang an cd bam ep nude cao han phuang an khai thac bing nang lugng ty nhien (Hinh 7) Trong sa dd khai thac thCr edng nghiep tang mdng md Bach Hd nam 1990, vdi phuang an khai thac diu bing nang lugng ty nhien cua md, he sdthu hdi dau ehi dat 17%; - Trong Sa dd cdng nghe khai thac va xay dyng md Bach Hd nam 1993, vdi phuang an khai thac bing he thdng ddi va giu ap suit via tUng phin, he sd thu hdi diu dat 22,3%; Tang mong mo Bach Ho TlNH TOAN SO SANH SAN Ll/ONG HAI PHl/ONG AN 5,000 4,500 ' Phi/ang an khai thac che toi i/u 4,000 c •a o £1 • Phi/dng an bdm ep ni/dc 3,500 3,000 2,500 2,000 c 1,500 1,000