Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd" MO HlNH O A N H GIA CHAT Ll/ONG H 6 A PHAM XCf LV NL/CJC BI^N BOM ^P TANG THU H6I DAU TRONG DI^U KIEN D!A HOA Ly M6 BACH H6 Nguyen Dang Man Ton[.]
Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd" MO HlNH O A N H GIA C H A T Ll/ONG H A PHAM XCf LV NL/CJC BI^N BOM ^P TANG THU H6I DAU TRONG DI^U KIEN D!A - HOA - Ly M BACH H Nguyen Dang Man Tong cong ty Dau Le Nhu Tieu, Nguyen Thi Phuc Vien Dau ABSTRACT Enhancing Oil Recoveny (EOR) in the oil field by injecting seawater to the formation causes some aftermath among which the effect of sulfate reducing bacteha (SRB) is one of the severe problems The seawater used for injecting the injection wells in oil field is very rich in sulfate ion and microelements, because of that, it is a good medium for activating and growing SRB producing hydrogen sulfide polluting the environment and damaging the human health, souring the product and corroding the equipment Because of that, when using injecting seawater for EOR of Fractured Basement Resen/oir, we absolutely have to find the measures to prevent the activity and the overgrowth of SRB One of the best means used at the present time for that purpose Is the biocides The new technological and technical means for assessing the quality, efficiency and dosage of the injection biocides carryed on in the simulating formation condition (with highest temperature and pressure) at the flooding instrument "Core Flooding-Geornecanique" A new method for exactly assessing the activity of biocides, when using injecting seawater for EOR of Fractured Basement Resen/oir can also give the information about the SRB's cell density, the hydrogen sulfide content in the production fluid and gas, the oil biodegradation and the oil displacement efficiency etc in the both said cases The method is based on the oil field form The testing result could point out the activity of the biocides, and approximately what's their dosage, and what's their best combination should be used when injecting the injection wells by seawater for Enhanced Oil Recovery in the Fractured Basement resen/oir LMdoAu Bam ep nude bien vao md lam tang thu hdi dau; ddng thdi, ngoai y mudn cija ngudi, da tao dieu kien thuan lgi cho vi khuan khir sunphat (SRB) lay nhiim, hoat ddng va phat trien, sinh H2S rat nguy hai ddi vdi ngudi, thie't bi, mdi trudng va giam chat lugng san pham khai thac dau (Phu luc 1) Chinh vi vay, song song vgi chuang trinh tang thu hdi dau (EOR), dac biet sd dung bien phap bam ep nude bie'n giau sunphat,- nguyen td vi lugng, nhat thie't phai han che den mire tdi da su hoat ddng va phat trie'n cua SRB, ma mdt nhung bien phap hieu qua, thdng dung nhat hien la sCr dung cac hda pham diet vi khuan (Biocide) Bai viet gidi thieu mdt ky thuat - cdng nghe mdi danh gia tinh nang, hieu qua va xac dinh lieu lugng sat thue nhat eua cac hda pham diet vi khuan SRB tren md hinh md phdng dieu kien via md Bach Hd (bao gdm phuang phap thCr nghiem va thiet bi "Core Flooding eua hang Geomecanique", hien dat tai VPI) II MOT S DAC DI^M COA MO HINH THCT NGHIEM ThCr nghiem d dieu kien md hinh, md phdng dieu kien via, dac biet la nhiet dp va ap suat cao tuang duang vdi tang mdng md Bach Ho (150°C va 260 at) Trong qui trinh thCr nghiem va tinh nang cua thiet bi cho phep kiem soat theo ddi mgi hoat ddng va phat trien cua vi khuan khCr sunphat 155 Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Ho" Lay mau luu the de kiem tra, dem sd lugng, chung loai SRB tai cac thdi diem mong mudn ma khdng anh hudng den tien trinh thu nghiem Md hinh thu nghiem dugc ket ndi true tiep vdi thie't bi H2S sinh hoat ddng va phat trien eua SRB sudt qua trinh thu nghiem bang cac phuang phap khae Mae dii cac nha san xuat da md ta eae tieu chuan ky thuat rat cao quang cao, chao hang; song nhung thdng sd ky thuat, sd lieu thCr nghiem, dac eua phuang phap rat can thie't de danh gia dung hieu qua, kha nang diet khuan va lieu lugng tdi uu nhat eua eae biocide d dieu kien tuang thich vdi dieu kien dia chat va eae dieu kien hoa ly hien tai eua md dau, nham lua chon chinh xac ddn pha che va dua cac chi dan thCr nghiem edng nghiep ddi vdi hda pham cu the xCr ly nude bien bam ep tai hien trudng Md hinh thCr nghiem cung kiem chirng tinh kha thi va hieu qua kinh te cho tUng giai phap cdng nghe nang cao thu hdi dau, trudc tien hanh thu nghiem cdng nghiep dieu kien dia - hda - ly cu the cua md IIL QUI TRlNH THl^r NGHIEM T R E N T H I ^ T BI CORE FLOODING HANG GEOMECANIQUE Md hinh dugc thie't lap tren thie't bi mang ten "Core Flooding cua hang Geomecanique", hien dang van hanh tai Vien Dau (Phu luc 2) Thiet bi cho phep tao va tri ap suat on dinh tdi 500 at vdi nhiet dp dn dinh tdi 150°C Miu Idi cua da ehUa, vi du da mdng, eae luu the ed via ma quan trgng nhat la nude via va cac chung SRB da phan lap tu md dau (Dat cac binh thu) se ddng thdi tham gia vao qua trinh thu, tao nen mdi trudng tdng the gan gidng vdi dieu kien dia - hda - ly via Lay mau luu the tai eae thdi diem khae (B04) de dem sd lugng, chung loai SRB, hoan toan co kha nang kiem soat dugc su hoat ddng va phat trien cua SRB sudt thdi gian thu nghiem ma tuyet ddi khdng anh hudng den toan bd qua trinh thCr nghiem keo dai nhieu Md hinh dugc ket ndi md hinh thCr nghiem vdi thie't bi chuyen dung de true tiep HjS va cac sunphua sinh qua trinh thCf nghiem, cd the linh hoat HjS va sunphua bang nhieu phuang phap khae nhu hap thu, sac ky FPD, chuan dp thiosunphat Md hinh md phdng ndi tren da tien hanh khao sat su hoat ddng va phat trien cua mdt sd chung SRB phan lap tU cac via san pham tang Oligoxen (GK 14) va tang mdng (GK 110, 801) md Bach Hd da dugc nhan gidng va bao quan qua trinh nghien cUu ve ngudn gdc sinh hoc cua H2S tai md Bach Hd (Bang va Phu luc 3) Thi nghiem dugc tien hanh lien tue nhieu d ap suat 260 at va nhiet 120°C Day la dieu kien ap suat va nhiet dugc xem la tuang ddng vgi ap suat va nhiet ndi chung cua md Bach Hd Ket qua thir nghiem da ehUng td rang vi khuan khCr sunphat chang nhung cd the tdn tai ma cdn cd kha nang phat trien, tao H2S nhung dieu kien tuang tu vdi dieu kien via ca tai tang mdng md Bach Hd (Bao cao nhiem vu nghien eCru khoa hgc cap nganh "Nghien cUu ngudn gdc HjS va de xuat cac giai phap xCr ly tai md Bach Hd, VPI, TCTy, 2001) Dieu dd cung cho thay, hieu qua eua biocide se khdng dugc danh gia chinh xac neu khdng thie't lap dugc qui trinh thCr nghiem dieu kien tuang ddng nhu dieu kien via, nai ma ca hai dang ngu (dormant) va dang hoat ddng (active) cua vi khuan khCr sunphat ludn ludn tdn tai, hoat ddng va phat trien, chuyen hda eae hgp chat luu huynh HjS (Phu luc 3) Ngoai ra, chung tdi cung da sCr dung md hinh tren de khao sat su bien ddi cua dau md ben via dau gieng 14 md Bach Hd lam tang linh ddng cua dau via san pham dudi tac ddng eCia cac vi khuan phan huy dau thd (Biodegradation), bi va khdng bi phan b§ng each quan sat phd sac ky toan phan eua dau (Whole oil) hai trudng hgp ed mat va khdng ed mat (tiet trung) vi khuan (Phu luc 4) 156 Hdi thdo khoa hoc "Ndng cao he sd thu hdi ddu md Bach Hd " Bang Lugng te bao vi khuan 801 G8 va H2S thoat khdi md hinh dieu kien thi nghiem d 120°C va 260atm Miu do! chUng Mau thCr nghiem Thdi gian thiJf ; nghiem, gid }- SRB, te bao/ml HjS, mg/ml SRB, te bao/ml H2S, mg/ml L A 25.5 0 25.5 10' 25.5 - - - 10' 10' 34.0 - - - 72 10' 10' 34.0 0 25.5 96 10' 10' 42.5 - - - 120 10' 10' 34.0 - - - 144 10' 10' 34.0 0 25.5 L A 10^ 10^ 24 10' 48 ! Thie't bi se la phuang tien huu hieu, die luc, thuan lgi de kiem soat chat che mgi qua trinh xay thdi gian tien hanh thCr nghiem, khdng chi danh gia cac hoa pham de xCr ly nude bam ep ma cdn danh gia sat thuc hieu qua kinh te, tinh kha thi cua cac giai phap edng nghe sinh hgc, hda hoc, hda ly, vi sinh nham tang cudng thu hdi dau va gia tang san lugng dau khai thac se lua chon de ap dung cho mdt md cu the Thi du ve danh gia hieu qua eCia cac hda pham diet khuan bang thCr nghiem theo md hinh (Phu luc 2), cac chat diet khuan dugc dua vao binh B02 va B03; so sanh dien bie'n cua qua trinh xay giua binh B02 va B03 thu nghiem (Cd biocide) va binh B01 ddi ehUng (khdng ed biocide) chung ta se biet dugc tinh nang, hieu qua va muc tac dung cua biocide ddi vdi vi khuan khCr sunphat nhung dieu kien thCr nghiem cu the Tren ea sd nhung ket qua khao sat thCr nghiem va sd lieu dugc, ed the dua dan pha che, lieu lugng thich hgp ddi vdi mdt hay mdt td hgp Biocide cu the se dugc su dung xCr ly nuge bien bam ep tai md Tuy nhien de cd dCi so lieu, thdng sd ky thuat tranh dugc su tuang tac cua hoa pham cho muc dich, yeu cau ndi tren can phai tien hanh nhieu thu nghiem d cac dieu kien tuang ddng vdi dieu kien cua md IV K^T L U A N Thie't bi "Core Flooding" hang Geomecanique cua Vien Dau la thiet bi chuyen dung ddi mdi nhat la cdng cu huu hieu va dac luc cho viec danh gia dung va sat thue hieu qua, tinh nang va xac dinh lieu lugng cac hoa pham diet khuan; ddng thdi giam sat, theo ddi didn bie'n sudt qua trinh thCr nghiem, md hinh thu nghiem ket ndi true tiep vdi thie't bj H2S sinh sudt thdi gian thCr nghiem va lay eae m i u luu the de kiem tra, dem sd lugng, chung loai SRB tai eae thdi diem mong mudn ma khdng anh hudng den tien trinh thCr nghiem Nhung ket qua va cac thdng sd ky thuat eua thCr nghiem thu dugc lam cd sd du lieu khoa hgc tin cay de dua chi din thich hgp dieu chinh, pha che cac chat diet khuan hgp ly nhat cho thu nghiem cdng nghiep xCr ly nude bien bam ep vao md Tren ea sd ket qua thuc nghiem da dat dugc, de nghi sCr dung md hinh md phdng dieu kien via thCr nghiem nham muc dich danh gia dung hieu qua, tinh nang va xac dinh lieu lugng eua eae hda pham diet vi khuan khu sunphat, Md hinh ky thuat - cdng nghe thCr nghiem tren thie't bi "Core Flooding" cua Vien Dau (Phu luc 2), ddng thdi, danh gia sat thuc ve hieu qua kinh te, tinh kha thi eua nhung giai phap cdng nghe (sinh hoc, hda hoc, hda ly, vi sinh) mdi de nang cao thu hdi dau va gia tang san lugng khai thac dau md hinh md phdng dieu kien dia - hda - ly cua via, cua md trudc tien hanh thu nghiem cdng nghiep d mdt md cu the, dac biet la dieu kien ap suat va nhiet cao eua md Bach Hd 157 Hdi thdo khoa hoc "Naiw coo he so Ihu hdi ddu mo Bach Hd" PHULUC MC HlNH O A N H GIA CHAT Ll/ONG HOA P H A M X(S LY NL/OC B I ^ N BOM EP, T A N G THU H | DAU T R O N G O I ^ U K I E N | A - HOA - LV M BACH H Phu l u c l Md hinh chua hoa tdng quat ddi vdi md tang thu hdi dau bang bdm ep nude bien (Theo Peter Sandrs and al .1996) Production well Sea water injection weii — _ SRIl l.NrRODLCtai i , n i ! Khu virc Khanangcliiiiihoa Jo m-SRB T.B T.B Ihip ^ ihap ihap Klia naiie thua lioa dn T-SRB Ihap TB cao T.B TB/cao Phu luc 2: ThCr nghiem md hinh via (tren thiet bi" Core Flooding" tai VPI) Sd mo hinh thif nghiem danh gia hieu qua Biocide (Mo hinh mo phong via) P1^P1B.P1A,P1B _ Bom tao 4p suSl B01_B^ c^tra mau d6i chimg B02S03_Binh chua mau t^ i nghiSm B04_ B4 (iung oj I4> miu 158 Hoi thao khoa hoc "Nang cao he sd Ihu hoi ddn mo Bach Hd " Phu luc Vi khuan khu sunphat HjS chung vi khuan 801 G8 sinh dieu l