Mô hình đánh giá chất lượng hóa phẩm xử lý nước biển bơm ép tăng thu hồi dầu trong điều kiện địa-hóa-lý mỏ Bạch Hổ

Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd"<br /> <br /> <br /> <br /> <br /> MO HlNH O A N H GIA C H A T Ll/ONG H 6 A PHAM XCf LV NL/CJC BI^N BOM ^P<br /> TANG THU H6I DAU TRONG DI^U KIEN D!A - HOA - Ly M 6 BACH H 6<br /> <br /> Nguyen Dang Man<br /> Tong cong ty Dau khi<br /> Le Nhu Tieu, Nguyen Thi Phuc<br /> Vien Dau khi<br /> <br /> ABSTRACT<br /> Enhancing Oil Recoveny (EOR) in the oil field by injecting seawater to the formation causes some aftermath<br /> among which the effect of sulfate reducing bacteha (SRB) is one of the severe problems. The seawater used for<br /> injecting the injection wells in oil field is very rich in sulfate ion and microelements, because of that, it is a good<br /> medium for activating and growing SRB producing hydrogen sulfide polluting the environment and damaging the<br /> human health, souring the product and corroding the equipment.<br /> Because of that, when using injecting seawater for EOR of Fractured Basement Resen/oir, we absolutely<br /> have to find the measures to prevent the activity and the overgrowth of SRB. One of the best means used at the<br /> present time for that purpose Is the biocides.<br /> The new technological and technical means for assessing the quality, efficiency and dosage of the injection<br /> biocides carryed on in the simulating formation condition (with highest temperature and pressure) at the flooding<br /> instrument "Core Flooding-Geornecanique".<br /> A new method for exactly assessing the activity of biocides, when using injecting seawater for EOR of<br /> Fractured Basement Resen/oir can also give the information about the SRB's cell density, the hydrogen sulfide<br /> content in the production fluid and gas, the oil biodegradation and the oil displacement efficiency etc. in the both<br /> said cases.<br /> The method is based on the oil field form. The testing result could point out the activity of the biocides, and<br /> approximately what's their dosage, and what's their best combination should be used when injecting the injection<br /> wells by seawater for Enhanced Oil Recovery in the Fractured Basement resen/oir<br /> <br /> LMdoAu<br /> Bam ep nude bien vao md lam tang thu hdi dau; ddng thdi, ngoai y mudn cija con ngudi, da tao ra dieu<br /> kien thuan lgi cho vi khuan khir sunphat (SRB) lay nhiim, hoat ddng va phat trien, sinh ra khi H2S rat nguy hai<br /> ddi vdi con ngudi, thie't bi, mdi trudng va giam chat lugng san pham khai thac dau khi (Phu luc 1). Chinh vi vay,<br /> song song vgi chuang trinh tang thu hdi dau (EOR), dac biet khi sd dung bien phap bam ep nude bie'n giau<br /> 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<br /> trong nhung bien phap hieu qua, thdng dung nhat hien nay la sCr dung cac hda pham diet vi khuan (Biocide).<br /> <br /> Bai viet gidi thieu mdt ky thuat - cdng nghe mdi danh gia tinh nang, hieu qua va xac dinh lieu lugng sat<br /> thue nhat eua cac hda pham diet vi khuan SRB tren md hinh md phdng dieu kien via md Bach Hd (bao gdm<br /> phuang phap thCr nghiem va thiet bi "Core Flooding eua hang Geomecanique", hien dat tai VPI).<br /> <br /> II. MOT S 6 DAC DI^M COA MO HINH THCT NGHIEM<br /> 1. ThCr nghiem d dieu kien md hinh, md phdng dieu kien via, dac biet la nhiet dp va ap suat cao tuang<br /> duang vdi tang mdng md Bach Ho (150°C va 260 at).<br /> <br /> 2. Trong qui trinh thCr nghiem va tinh nang cua thiet bi cho phep kiem soat theo ddi mgi hoat ddng va<br /> phat trien cua vi khuan khCr sunphat.<br /> <br /> <br /> <br /> 155<br /> Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Ho"<br /> <br /> <br /> <br /> 3. Lay mau luu the de kiem tra, do dem sd lugng, chung loai SRB tai cac thdi diem mong mudn ma khdng<br /> anh hudng den tien trinh thu nghiem.<br /> 4. Md hinh thu nghiem dugc ket ndi true tiep vdi thie't bi do khi H2S sinh ra do hoat ddng va phat trien eua<br /> SRB trong sudt qua trinh thu nghiem bang cac phuang phap do khae nhau.<br /> 5. Mae dii cac nha san xuat da md ta eae tieu chuan ky thuat rat cao trong quang cao, chao hang;<br /> song nhung thdng sd ky thuat, sd lieu thCr nghiem, do dac eua phuang phap nay rat can thie't de danh gia dung<br /> hieu qua, kha nang diet khuan va lieu lugng tdi uu nhat eua eae biocide d dieu kien tuang thich vdi dieu kien dia<br /> chat va eae dieu kien hoa ly hien tai eua md dau, nham lua chon chinh xac ddn pha che va dua ra cac chi dan<br /> thCr nghiem edng nghiep ddi vdi hda pham cu the trong xCr ly nude bien bam ep tai hien trudng.<br /> <br /> 6. Md hinh thCr nghiem cung kiem chirng tinh kha thi va hieu qua kinh te cho tUng giai phap cdng nghe<br /> nang cao thu hdi dau, trudc khi tien hanh thu nghiem cdng nghiep trong dieu kien dia - hda - ly cu the cua md.<br /> <br /> IIL QUI TRlNH THl^r NGHIEM T R E N T H I ^ T BI CORE FLOODING HANG GEOMECANIQUE<br /> Md hinh dugc thie't lap tren thie't bi mang ten "Core Flooding cua hang Geomecanique", hien dang van<br /> hanh tai Vien Dau khi (Phu luc 2).<br /> Thiet bi cho phep tao va duy tri ap suat on dinh tdi 500 at vdi nhiet dp dn dinh tdi 150°C. Miu Idi cua da<br /> ehUa, vi du da mdng, eae luu the ed trong via ma quan trgng nhat la nude via va cac chung SRB da phan lap tu<br /> md dau... (Dat trong cac binh thu) se ddng thdi tham gia vao qua trinh thu, tao nen mdi trudng tdng the gan<br /> gidng vdi dieu kien dia - hda - ly via.<br /> Lay mau luu the tai eae thdi diem khae nhau (B04) de do dem sd lugng, chung loai SRB, hoan toan co<br /> kha nang kiem soat dugc su hoat ddng va phat trien cua SRB trong sudt thdi gian thu nghiem ma tuyet ddi<br /> khdng anh hudng den toan bd qua trinh thCr nghiem keo dai nhieu ngay.<br /> Md hinh dugc ket ndi md hinh thCr nghiem vdi thie't bi chuyen dung de do true tiep khi HjS va cac<br /> sunphua sinh ra trong qua trinh thCf nghiem, cd the linh hoat do HjS va sunphua bang nhieu phuang phap do<br /> khae nhau nhu hap thu, sac ky FPD, chuan dp thiosunphat.<br /> Md hinh md phdng ndi tren da tien hanh khao sat su hoat ddng va phat trien cua mdt sd chung SRB<br /> phan lap tU cac via san pham tang Oligoxen (GK 14) va tang mdng (GK 110, 801) md Bach Hd da dugc nhan<br /> gidng va bao quan trong qua trinh nghien cUu ve ngudn gdc sinh hoc cua H2S tai md Bach Hd (Bang 1 va Phu<br /> luc 3). Thi nghiem dugc tien hanh lien tue trong nhieu ngay d ap suat 260 at va nhiet do 120°C. Day la dieu kien<br /> ap suat va nhiet do dugc xem la tuang ddng vgi ap suat va nhiet do ndi chung cua md Bach Hd. Ket qua thir<br /> nghiem da ehUng td rang vi khuan khCr sunphat chang nhung cd the tdn tai ma cdn cd kha nang phat trien, tao<br /> H2S trong nhung dieu kien tuang tu vdi dieu kien via ngay ca tai tang mdng md Bach Hd (Bao cao nhiem vu<br /> nghien eCru khoa hgc cap nganh "Nghien cUu ngudn gdc HjS va de xuat cac giai phap xCr ly tai md Bach Hd,<br /> VPI, TCTy, 2001).<br /> <br /> Dieu dd cung cho thay, hieu qua eua biocide se khdng dugc danh gia chinh xac neu khdng thie't lap dugc<br /> qui trinh thCr nghiem trong dieu kien tuang ddng nhu dieu kien via, nai ma ca hai dang ngu (dormant) va dang<br /> hoat ddng (active) cua vi khuan khCr sunphat ludn ludn tdn tai, hoat ddng va phat trien, chuyen hda eae hgp chat<br /> luu huynh thanh HjS (Phu luc 3).<br /> <br /> Ngoai ra, chung tdi cung da sCr dung md hinh tren de khao sat su bien ddi cua dau md ben trong via dau<br /> gieng 14 md Bach Hd lam tang do linh ddng cua dau trong via san pham dudi tac ddng eCia cac vi khuan phan<br /> huy dau thd (Biodegradation), bi va khdng bi phan ra b§ng each quan sat phd sac ky toan phan eua dau (Whole<br /> oil) trong hai trudng hgp ed mat va khdng ed mat (tiet trung) vi khuan (Phu luc 4).<br /> <br /> <br /> <br /> 156<br />  Hdi thdo khoa hoc "Ndng cao he sd thu hdi ddu md Bach Hd "<br /> <br /> <br /> <br /> Bang 1. Lugng te bao vi khuan 801 G8 va H2S thoat ra khdi md hinh<br /> trong dieu kien thi nghiem d 120°C va 260atm<br /> Mau thCr nghiem Miu do! chUng<br /> Thdi gian thiJf ;<br /> SRB, te bao/ml SRB, te bao/ml<br /> nghiem, gid }- HjS, mg/ml H2S, mg/ml<br /> L A L A<br /> 0 ! 10^ 10^ 25.5 0 25.5<br /> 0<br /> 24 10' 10' 25.5 - - -<br /> 48 10' 10' 34.0 - - -<br /> 72 10' 10' 34.0 0 0 25.5<br /> 96 10' 10' 42.5 - - -<br /> 120 10' 10' 34.0 - - -<br /> 144 10' 10' 34.0 0 0 25.5<br /> <br /> <br /> Thie't bi nay se la phuang tien huu hieu, die luc, thuan lgi de kiem soat chat che mgi qua trinh xay ra<br /> trong thdi gian tien hanh thCr nghiem, khdng chi danh gia cac hoa pham de xCr ly nude bam ep ma cdn danh gia<br /> 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<br /> 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<br /> danh gia hieu qua eCia cac hda pham diet khuan bang thCr nghiem theo md hinh (Phu luc 2), cac chat diet khuan<br /> dugc dua vao binh B02 va B03; so sanh dien bie'n cua qua trinh xay ra giua binh B02 va B03 thu nghiem (Cd<br /> biocide) va binh B01 ddi ehUng (khdng ed biocide) chung ta se biet dugc tinh nang, hieu qua va muc do tac<br /> dung cua biocide ddi vdi vi khuan khCr sunphat trong nhung dieu kien thCr nghiem cu the. Tren ea sd nhung ket<br /> qua khao sat thCr nghiem va sd lieu do dugc, ed the dua ra dan pha che, lieu lugng thich hgp ddi vdi mdt hay<br /> mdt td hgp Biocide cu the se dugc su dung trong xCr ly nuge bien bam ep tai md. Tuy nhien de cd dCi so lieu,<br /> thdng sd ky thuat tranh dugc su tuang tac cua hoa pham cho muc dich, yeu cau ndi tren can phai tien hanh<br /> nhieu thu nghiem d cac dieu kien tuang ddng vdi dieu kien cua md.<br /> <br /> IV. K^T L U A N<br /> <br /> Thie't bi "Core Flooding" hang Geomecanique cua Vien Dau khi la thiet bi chuyen dung ddi mdi nhat la<br /> 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<br /> hoa pham diet khuan; ddng thdi giam sat, theo ddi didn bie'n sudt qua trinh thCr nghiem, md hinh thu nghiem ket<br /> ndi true tiep vdi thie't bj do khi H2S sinh ra trong sudt thdi gian thCr nghiem va lay eae m i u luu the de kiem tra, do<br /> dem sd lugng, chung loai SRB tai eae thdi diem mong mudn ma khdng anh hudng den tien trinh thCr nghiem.<br /> <br /> Nhung ket qua va cac thdng sd ky thuat eua thCr nghiem thu dugc lam cd sd du lieu khoa hgc tin cay de<br /> dua ra chi din thich hgp dieu chinh, pha che cac chat diet khuan hgp ly nhat cho thu nghiem cdng nghiep xCr ly<br /> nude bien bam ep vao md.<br /> <br /> Tren ea sd ket qua thuc nghiem da dat dugc, de nghi sCr dung md hinh md phdng dieu kien via thCr<br /> nghiem nham muc dich danh gia dung hieu qua, tinh nang va xac dinh lieu lugng eua eae hda pham diet vi<br /> khuan khu sunphat,<br /> <br /> Md hinh ky thuat - cdng nghe thCr nghiem tren thie't bi "Core Flooding" cua Vien Dau khi (Phu luc 2), ddng<br /> thdi, danh gia sat thuc ve hieu qua kinh te, tinh kha thi eua nhung giai phap cdng nghe (sinh hoc, hda hoc, hda<br /> ly, vi sinh) mdi de nang cao thu hdi dau va gia tang san lugng khai thac dau khi trong md hinh md phdng dieu<br /> kien dia - hda - ly cua via, cua md trudc khi tien hanh thu nghiem cdng nghiep d mdt md cu the, dac biet la dieu<br /> kien ap suat va nhiet do cao eua md Bach Hd.<br /> <br /> <br /> <br /> 157<br /> Hdi thdo khoa hoc "Naiw coo he so Ihu hdi ddu mo Bach Hd"<br /> <br /> <br /> <br /> PHULUC<br /> <br /> <br /> 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,<br /> T A N G THU H 6 | DAU T R O N G O I ^ U K I E N 0 | A - HOA - LV M 6 BACH H 6<br /> <br /> <br /> <br /> <br /> Phu l u c l . Md hinh chua hoa tdng quat ddi vdi md tang thu hdi dau bang bdm ep nude bien.<br /> (Theo Peter Sandrs and al. .1996)<br /> <br /> <br /> Sea water injection weii Production well<br /> — 3 _<br /> <br /> <br /> SRIl<br /> <br /> l.NrRODLCtai i , n i !<br /> <br /> <br /> <br /> <br /> Khu virc 1 2 . ^ 4 5<br /> Khanangcliiiiihoa Jo m-SRB T.B T.B Ihip ihap ihap<br /> <br /> Klia naiie thua lioa dn T-SRB Ihap TB cao T.B TB/cao<br /> <br /> <br /> <br /> <br /> Phu luc 2: ThCr nghiem md hinh via (tren thiet bi" Core Flooding" tai VPI).<br /> <br /> <br /> <br /> Sd do mo hinh thif nghiem danh gia hieu qua Biocide<br /> (Mo hinh mo phong via)<br /> <br /> <br /> <br /> <br /> P1^P1B.P1A,P1B _ Bom tao 4p suSl<br /> <br /> B01_B^ c^tra mau d6i chimg.<br /> <br /> B02S03_Binh chua mau t^. i nghiSm.<br /> <br /> B04_ B4 (iung oj I4> miu<br /> <br /> <br /> <br /> <br /> 158<br />  Hoi thao khoa hoc "Nang cao he sd Ihu hoi ddn mo Bach Hd "<br /> <br /> <br /> <br /> Phu luc 3. Vi khuan khu sunphat HjS do chung vi khuan 801 G8 sinh ra<br /> chuyen hda hgp chat luu huynh tao HjS. trong dieu l61 chOng<br /> a—<br /> 25 ^ -<br /> <br /> <br /> 2 0 ^ 1 1 , 1 1 1 —<br /> <br /> <br /> Phu luc 4. Su bie'n ddi dau trong thCr 0 24 48 72