Phương pháp xử lý sản phẩm các giếng khai thác nhằm nâng cao sản lượng dầu

Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bqch Hd"<br /> <br /> <br /> <br /> <br /> PHL/ONG PHAP xd Lt SAN PHAM CAC G I ^ N G KHAI THAC<br /> NHAM NANG CAO SAN LLTONG DAU<br /> <br /> Nguyen Thuc Khang. Ha Van Bich<br /> Tong Canh San, Le Dinh Hoe<br /> XNLD Vietsovpetro<br /> Phung Dinh Thuc<br /> Cong ty Tham do va Khai thac<br /> <br /> ABSTRACT<br /> The oil recovery enhancement is one of the strategic targets not only for Oil Companies in general, but also<br /> for JV Vietsovpetro particularly. This paper presents the results of laboratory tests and field thai of injection of<br /> chemical composition. The chemical composition of wax inhibitor and surfactant was injected to the gaslift wells at<br /> MSP-5 and MSP-7 at White Tiger Field and well 5P at Dai Hung field. The flow rate of tested wells increased from<br /> 7.1 to 80.0%, gas consumption decreased from 5.6 to 32.7% and wax deposition was inhibited at 12.1-14.1%o,<br /> showed effectiveness and field application ability of implemented technology. Fudher wide realization of technology<br /> will bring to JV Vietsovpetro significant benefits.<br /> <br /> <br /> OAT VAN 0^<br /> Hien nay, tdng san lugng dau khai thac tu eae md eua XNLD Vietsovpetro dat mCre khoang 13 tr. tan/nam<br /> va ehCi yeu la khai thac tU tang mdng eua md Bach Hd.<br /> <br /> Nhung nam gan day san lugng dau eua nhieu gie'ng khai thac bang phuang phap tu phun d cac tang san<br /> pham Mioxen, Oligoxen va tham ehi ea tang mdng dang giam dan. Oe duy tri san luang khai thac, hang loat eae<br /> gie'ng tu phun ed san lugng va ap suat mieng thap dugc chuyen sang khai thac bang phuang phap ca hoc dung<br /> khi nen (gaslift), hoae bam dien ngam. Viec khai thac bang phuang phap gaslift d md Bach Hd dugc thuc hien<br /> bang ngudn khi do gian nen khi nhd (MKS) dat d khu vuc gian ed dinh sd 4 (MSP-4) cung cap. Cung vdi thdi<br /> gian, ty le sd gie'ng va lugng dau khai thac bang eae phuang phap ca hgc tai md ngay cang gia tang, tU mUc<br /> 2000 t/ngd nhu hien nay va se tiep tue tang d nhung nam tdi.<br /> <br /> Nghien cUu qua trinh lam viec cua cac gie'ng gaslift cho thay: Hieu qua lam viec eua cac gie'ng khai thac<br /> chua cao va ed chieu hudng giam. Theo sd lieu do dac tai mdt sd gie'ng d gian MSP-1 thi hieu qua lam viec cua<br /> cac gie'ng da giam tU 10.7-20.1% eua nam 1993 xudng edn 3.6-6.7% trong nam 1996 [1]. Nguyen nhan trudc<br /> het la do mUe dp ngap nude d cac gie'ng nay tang, lang dpng paraffin cao, tinh chat luu chuyen eua ddng san<br /> pham dpc theo than gie'ng kem, thie't dien dng khai thac bi thu hep. Ket qua la san lugng dau eua cac gie'ng<br /> giam dan va kha nang thu hdi dau se thap.<br /> <br /> 6 day ehijng tdi se trinh bay viec Crng dung cdng nghe xCr ly ddng san pham trong dng nang cua cac gieng<br /> gaslift eua md Bach Hd va dng d i n dau md Dai Hung nham gia tang san lugng khai thac dau va tang eugng kha<br /> nang lam viec eua gieng, la mdt trong nhung bien phap nang cao he sd thu hdi dau tU eae md.<br /> <br /> I. CAC Y^U T 6 ANH HLTdNG O ^ N S A N LLTONG KHAI THAC DAU 6 CAC GI^NG GASLIFT<br /> <br /> Hieu qua lam viec cua eae gie'ng gaslift tai md Bach Ho phu thudc rat nhieu vao kha nang luu chuyen eua<br /> hdn hgp dau - khi - nude trong dng khai thac va muc dp tao bgt khi trong dau va kha nang khuyech tan chung<br /> trong ddng san pham.<br /> <br /> Dau khai thac d tat ca cac tang san pham cua md Bach Ho la dau cd ham lugng paraffin cao (17-27%).<br /> Nhiet do ket tinh paraffin trong dau dao ddng d khoang 5 8 - 6 f C va nhiet dp ddng dac eua dau la 32-36°C.<br /> <br /> <br /> <br /> 179<br /> Hdi thdo khoa hoc "Ndng cao he sd thu hdi ddu md Bqch Ho"<br /> <br /> <br /> <br /> Trong khi dd, nhiet dp dau tai mieng gieng eua hau het eae gie'ng gaslift, ehi d khoang 26-50°C, din den kha<br /> nang nang cua san pham thap. Ngoai ra, ben trong thanh dng khai thac edn xuat hien Idp lang dgng paraffin.<br /> Theo qua trinh khai thac chieu day igp lang dgng nay Idn dan se lam giam thie't dien dng khai thac, nhu vay<br /> kha nang khai thac dau giam dan va eudi cung tham chi ed the phai dUng khai thac. Van de nay edn dac biet<br /> nghiem trgng khi ham luang nude trong dau tang. Viec gia tang ham lugng nuge trong hdn hgp dau - khi ed<br /> the cdn tao dieu kien ket tinh d at paraffin trong dau, lam day them Idp lang dgng paraffin, giam kha nang luu<br /> chuyen cCia ddng chat luu trong than gieng, ddng thdi gay nhieu tdn that nang lugng han. Ngoai ra, su xuat<br /> hien nude trong san pham cCia cac gieng gaslift cdn lam giam kha nang duy tri bgt khi trong dau va tang kha<br /> nang tach khi ra khdi chat Idng. Cudi cung la kha nang lam viec va san lugng khai thac eua eae gieng gaslift<br /> giam dang ke.<br /> <br /> Su anh hudng len che do lam viec cua cac gieng gaslift do su hien dien eua nude trong ddng san pham<br /> cd the dugc giai thich bang nhung nguyen nhan sau day:<br /> - Khi nude xuat hien, tinh chat ly hda eua hdn hgp dau - khi - nuge trd nen khae nhieu so vdi tinh chat<br /> cua hdn hgp dau - khi, lam tang dp n\\(A eua hdn hgp len nhieu lan. Ngoai ra, do nhgt cua hdn hgp dau - khi-<br /> nude phij thudc rat nhieu vao thanh phan cac chat tham gia va dp phan tan cua chung trong nhau.<br /> - Viec gia tang ham lugng nude trong ddng san pham lam thay ddi tdc do tudng ddi cCia ddng khi, tang<br /> khdi lugng rieng eua ddng san pham trong dng khai thac va lam tang tdn hao ap suat de nang san pham len,<br /> hieu qua lam viec eua khi trong dau giam, chi phi khi edng tac cao, kha nang luu chuyen cCia ddng chat luu<br /> trong dng thap, lang dgng paraffin ben trong thanh dng khai thac tang.<br /> Oe danh gia hieu qua lam viec cua cac gie'ng dau cd the xem xet va phan tich tren ca sd cdng thCrc xac<br /> dinh he sd nang hieu dung cua cac gie'ng gaslif nhu sau:<br /> <br /> ri = — ^ (1)<br /> <br /> <br /> <br /> Trong dd.' Cj- Van tdc tuang ddi cua pha khi, m/s;<br /> q - Luu lugng chat Idng eua gie'ng, mVs;<br /> f- Thiet dien dng khai thac, m^;<br /> p,- Ap suat khi edng tac sau van. Pa;<br /> Py - Ap suat mieng gie'ng. Pa;<br /> h - Chieu dai dng nang, m;<br /> p - Ty trpng trung binh eCia he dau va khi, kg/m^;<br /> g - Gia tdc rai tu do, m/sl<br /> Van tdc tuang ddi cua pha khi cang nhd thi he sd nang hieu dung eua cac gie'ng gaslift tang. Gia tri<br /> van tdc tuang ddi cua khi dugc xac dinh bdi muc dp phan tan khi trong mdi trudng chat Idng va ngoai ra edn<br /> phij thudc vao cac chi sd cdng nghe gie'ng khai thac. Trong dd, dieu kien de ddng san pham trong gie'ng dugc<br /> nang len mieng la:<br /> Dt > Dn (2)<br /> <br /> 0 day: Dt- Dugng kinh dng khai thac.<br /> Dn - Dudng kinh bgt khi tai mieng gie'ng.<br /> <br /> <br /> <br /> 180<br />  Hoi thao khoa hoc "Nang cao he so ihu hoi ddu mo Bach Ho"<br /> <br /> <br /> <br /> <br /> Nhu vay, neu mudn:<br /> - Giam thieu tdn that nang luang cua dong san pham trong dng khai thac;<br /> - Han che viec hinh thanh nhO tuang dau-nude ed dd ben va dp nhdt cao;<br /> - Tang cuang kha nang phan tan cac bot khi trong dau va hda tan mpt phan khi trong chat long d dieu<br /> kien ap suat lam viec cua gie'ng, ddng thdi tang tinh luu chuyen cua nhu tuang dau - nude;<br /> - Giam sUe cang be mat giua cac pha va han che lang dpng paraffin trong dng khai thac;<br /> Thi chung ta can bam vao dong san pham cua cac gie'ng gaslift mpt hdn hgp cac hda pham gdm eae<br /> chat cd tinh nang Uc che ling dgng paraffin va hoat ddng be mat.<br /> <br /> II. ANH H L T 6 N G CUA HOA PHAM O^N TINH LLTU CHUYEN COA NHG TLTONG OAU-NL/CJC, HAN CH^ LANG<br /> <br /> DONG PARAFFIN VA KHA NANG TAO BOT KHI TRONG OAu 6 CAC GI^NG GASLIFT<br /> <br /> 1. Anh hudng den do nhdt va qua trinh ling dgng paraffin<br /> <br /> Nhu ket qua cdng bd tai cac cdng tnnh nghien cuu [2, 3, 4] dau khai thac d eae gieng cua mo Bach Ho la<br /> dau cd ham luang paraffin va nhiet dd ddng dac cao, Khi nhiet dp giam xudng dudi nhiet do ket tinh paraffin, qua<br /> tnnh ket tinh paraffin trong dau bat dau xuat hien, Trong khi dd, nhu da ndi d tren, san pham cua phan Idn cac<br /> gie'ng gaslift d md Bach Hd ed nhiet dp mieng gieng thap han so vai nhiet do ket tinh paraffin va tham ehi cdn thap<br /> han ca nhiet dd ddng dac eua dau, Oe giam dd nhdt cua nhu tuang dau nude, cai thien tinh luu bie'n eua ddng san<br /> pham, ddng thdi han che lang dong paraffin, chung tdi da tien hanh nghien cuu kha nang su dung hdn hgp hda<br /> pham trong phong thi nghiem tren may do do n\\dX ROTOVISCO kieu RV-20 va thiet bi xac dinh lang dgng paraffin<br /> bang phuang phap ngdn tay lanh (cold finger), Ket qua nghien cUu duac tnnh bay trong Bang 1 va 2,<br /> <br /> <br /> Bang 1, Anh hudng eua hda pham giam nhiet dp ddng dac len dd nhdt cua dau md Bach Hd<br /> (nhiet dp xCr ly: 65'C, dinh luang hda pham:1000g/t)<br /> Do nhdt c ua dau tho mo Bach Ho (niPa*s) dcac d leu kien ng am nUdc (%)<br /> Nhiet do 0 10 30 40<br /> do>c' Chua Da XLfiy Chua OaxCrly ChUa DaxCfly ChUa OaxCrly<br /> xCrly hoa pham xCriy hoa pham XLf ly hoa pham xCrly hoa pham<br /> 60 4.5 5.2 6 6 8 12 8 15<br /> 50 5.0 6 7 8 11 15 22 17<br /> 40 5.4 7 8 9 18 19 32 27<br /> 35 11 8 71 12 54 35 180 52<br /> 30 127 15 325 23 323 63 575 137<br /> 26 481 28 725 49 1120 152 1482 309<br /> <br /> Bang 2. Anh hudng eua hda pham giam nhiet dp ddng dac<br /> len kha nang dc che lang dgng paraffin eua dau thd md Bach Hd<br /> OinhlUdng Thdi gian thCf Toe do lang dong Kha nang Uc che<br /> So Nhiet do<br /> hoa pham, g/t nghiem, gid : paraffin, g/m^/ngd ling dong, %<br /> TT dau, X'<br /> Nhiet do ngon tay lanh 22°C<br /> 60 0 8 3538<br /> 60 500 8 2433 31.2<br /> 60 1000 8 2354 33.5<br /> <br /> <br /> <br /> 181<br /> Hdi thdo khoa hoc "Ndng cao he sd thu hdi ddu md Bqch Ho"<br /> <br /> <br /> <br /> Ket qua trong Bang 1 va 2 cho thay khi sCr dung hda pham giam nhiet do ddng dac de xu ly, do nhdt<br /> cua nhu tuang dau - nugc khai thac tai md Bach Hd ed the giam tu 10 den 20 lan va Uc che lang dgng paraffin d<br /> mCre 31-33%.<br /> <br /> 2. Anh hudng den kha nang tao bot khi trong dau<br /> <br /> Oe xac dinh anh hudng eua chat hoat tinh be mat den hieu qua lam viec cCia khi trong cac gie'ng gaslift<br /> da tien hanh nghien cuu anh hudng cua hda pham pha nhu hien dang su dung d cac md cua XNLD den kha<br /> nang phan tan va tao eae bpt khi trong dau. Ket qua nghien eCru thi nghiem trinh bay trong Bang 3 cho thay<br /> viec sCr dung hda pham pha nhu vdi dinh lugng 200g/t lam tang kha nang tao cac bgt khi va do huyen phii<br /> cua chung trong san pham gie'ng khai thac. Khi muc do ngam nude eua hdn hgp tang thi kha nang duy tri cac<br /> bgt khi phan tan trong dau cang giam. Od la vi trong qua trinh chuyen ddng eua hdn hgp dau - khi - nuac dpc<br /> theo than gie'ng len mieng, su chenh lech ty trgng giua eae pha cua san pham tang len, tdc dp tuang ddi cua<br /> khi se tang, tinh linh ddng cua hdn hgp dau - nude giam dang ke, tdn that nang lugng de nang chat Idng len<br /> cang tang va nhu vay cac bgt khi trong dau d dang nhu dugc giai phdng khdi chat Idng cang nhanh. Khi cd su<br /> tac dung cua hda pham, eae chat hoat ddng be mat se duac hap thij len be mat giua eae eae pha va lam cho<br /> sUe cang be mat eua chung giam, khi cac bgt khi du ign nd se bi vd ra thanh eae bgt khi nhd han phan tan<br /> trong dau. Mat khae, vdi viec bam chat pha nhu "qua lieu lugng" vao nhu nguge "nuge trong dau" se tao dieu<br /> kien cho nd ddi pha thanh nhu thuan "dau trong nude". Nhu vay, viec su dung hda pham pha nhu d dinh<br /> lugng ign se duy tri duac muc do huyen phu eua eae bgt khi trong dau. Ket qua la khdi lugng rieng va do nhdt<br /> cua hdn hgp dau - khi - nuge trong dng khai thac giam, kha nang nang cCia san pham tang, luu lugng khai<br /> thac cua gie'ng se dugc cai thien.<br /> <br /> Bang 3. Anh hudng eua hda pham den kha nang tao bgt khi trong nhu tuang dau - nugc<br /> Ham lUdng nUdc Khong xCrly Coxijfly hoa pham CoxCrly hon hdp<br /> SoTT<br /> trong dau, % hoa pham pha nhu hoa pham<br /> 1 0 4.5 9.1 9.4<br /> 15 3.0 7.5 8.0<br /> 3 30 2.1 4.6 6.0<br /> 4 45 2.0 2.8 4.1<br /> <br /> III. K^T QUA THt!f NGHIEM C O N G N G H I | P T R E N CAC G I ^ N G GASLIFT M 6 BACH H 6<br /> Oe kiem nghiem cac ket qua nghien cuu tai phdng thi nghiem ve kha nang han che lang dgng paraffin,<br /> cai thien tinh luu bien eua chat luu, tang kha nang tao bpt khi trong hdn hgp dau - nuge trong cac gie'ng gaslift,<br /> tu 03.03 den 14.04.2000 XNLD Vietsovpetro da tien hanh thu nghiem edng nghiep phuang phap xd ly hda<br /> pham tai eae gie'ng #104 va #510 d gian khai thac MSP-5 va tU 14-27.08.2001 tai eae gie'ng #75,145, 702, 704<br /> va 715 d MSP-7 cua md Bach Hd.<br /> <br /> Muc dich cua dgt thu nghiem thang 03-04.2000 chu yeu la de xac dinh kha nang giam do nhdt cua san<br /> pham khai thac va do che ling dpng paraffin cua hdn hgp hda pham hien dang sCr dung d XNLD Vietsovpetro.<br /> Hdn hgp gdm 50% hda pham giam nhiet dp ddng dac va 50% hydroeaebon tham cao phan tCr dugc bam vao<br /> ddng san pham khai thac eua gie'ng gaslift thdng qua dudng khi edng tac eua he thdng cap khi nen. Ket qua thu<br /> nghiem trinh bay trong Bang 4 cho thay: Mae du nhiet dd dau tai mieng gie'ng thap (26-32°C) nhung too dp lang<br /> dgng paraffin ben trong dng khai thac eua gie'ng giam duac 12.1-14.1% (xac dinh bang phuang phap ea hgc),<br /> chi phi khi edng tac giam dugc 21-32%. San lugng dau khai thac trung binh cua gie'ng #104 tang them 7.5 t/ngd.<br /> va gieng #510-14.5 t/ngd.<br /> <br /> <br /> 182<br />  Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bach Hd'<br /> <br /> <br /> <br /> Thu nghiem cdng nghiep dgt thang 08.2001 nham xac dinh tac dung eua hdn hgp eae hda pham giam<br /> nhiet dd ddng dac (60%) va chat chat pha nhu (40%) len san lugng khai thac dau eua eae gie'ng gaslift. Hdn hgp<br /> hda pham duac bam vao san pham khai thac eua eae gie'ng 75,145, 702, 704 va 715 (MSP-7) tuang tu nhu thCr<br /> nghiem tren MSP-5. Nhiet dp dau tai mieng gie'ng dao dgng d khoang 28-51°C, thap nhat la gie'ng #704, khoang<br /> 28-29''C, va cao nhat la gieng #702- 50-5fC. Ham lugng nude trong san pham cua eae gie'ng nay thay ddi tU 0<br /> den 68%. Ket qua cho thay viec sCr dung hdn hgp hda pham vdi dinh lugng tU 500-1000 g/t giup gia tang san<br /> lugng khai thac them 9.3-29.9% (xem Bang 4).<br /> <br /> Bang 4. Ket qua thCr nghiem edng nghiep tai eae gieng gaslift d md Bach Hd<br /> Chi phi khi cong tac, m^/m^ Giam ling LUu lUdng dau, t/ngd<br /> Gieng so Khixu'ly . .' , , , dong paraffin, T- . , , . KhixUly<br /> TrUdc XLf ly pham, kg/ngd ; • " " ; TrUdc xU ly . . . .'<br /> hoa pham /o ' hoa pham<br /> Thdi gian thCr nghiem tU 03.03-14.04.2000<br /> <br /> 104 450 303 12-24 12.1 12.6 20.1<br /> 510 168 133 28-54 14.1 28.1 42.6<br /> Thdi gian thCr nghiem tU 14-27.08.2001<br /> <br /> 75 144 136 16 - 49 54<br /> 145 228 143 30 10-13 15<br /> 702 57 53 45 126 135<br /> 704 381 265 8.0 - 15 21.4<br /> 715 326 246 15 - 15.0 27<br /> <br /> <br /> IV, K^T QUA THllr N G H I E M VA AP DUNG C O N G N G H I $ P T R E N G I ^ N G 5P M 6 DAI HONG<br /> Tren md Dai Hung do lang dgng paraffin, nen dinh ky sau mdi 5 ngay lam viec dng mem din dau (dudng<br /> kinh 75 mm va chieu dai 2000m) tU gie'ng 5P len gian Dai Hung-01 (DH-01) phai dUng lai de phdng thoi lam<br /> sach, TU 15,10,2001 van de da dugc giai quyet bing each bam hda pham giam nhiet dp ddng dac vao mieng<br /> gieng 5P qua dudng do ap suat, Ket qua nhiet dd ddng dac cua dau giam tU 30°C xudng 24°C, kha nang luu<br /> thdng eua ddng san pham trong dng mem dugc cai thien rd ret va lang dgng paraffin ben trong dng mem eua<br /> gie'ng 5P da dugc khae phuc triet de. San lugng khai thac dau gie'ng 5P da tang tU 119.3 t/ngd (ngay 06.10.2001)<br /> len 128 t/ngd (ngay 26.10.2001) va den 136,6 t/ngd (ngay 26.04.2002). Phuang phap \d ly dau bang hda<br /> pham thanh edng d gie'ng 5P se dugc ap dung cho gie'ng 4X md Dai Hung.<br /> <br /> K^T LUAN<br /> <br /> 1. Su dung hda pham giam nhiet do ddng dac de xCr ly ddng san pham dau-khi-nude eua eae gieng gaslift<br /> cho phep giam dang ke do nhdt hieu dung eua chat luu, han che lang dgng paraffin trong dng khai<br /> thac, giam thieu tdn that nang lugng de nang san pham len mieng gieng va cudi cung la lam tang san<br /> lugng cua cac gie'ng gaslif;<br /> <br /> 2. Dung hda pham pha nhu ed the lam giam ehi phi khi cdng tac, duy tri kha nang tao bot khi va tang he<br /> sd nang hieu dung cua ddng san pham dau-khi-nude len mieng eae gie'ng gaslift d md Bach Hd;<br /> 3. Oe gia tang san luang dau eua cac gieng gaslift qua dudng cung cap khi nen can phai bam vao ddng<br /> san pham khai thac:<br /> <br /> <br /> <br /> <br /> 183<br /> Hdi thdo khoa hoc "Ndng cao he sdthu hdi ddu md Bach Ho"<br /> <br /> <br /> <br /> - Odi vdi cac gieng chua ngap nude: hoa pham giam nhiet do ddng dac;<br /> <br /> - Odi vdi cac gieng da ngap nude: hdn hgp cac hoa pham giam nhiet do ddng dac va chat pha nhu;<br /> <br /> - Oinh lugng hda pham/hdn hgp cac hda pham khoang 1000 g/t.<br /> <br /> <br /> TAI L I $ U THAM KHAO<br /> <br /> 1. Lua chgn hdn hgp chat hoat ddng be mat de nang cao he sd nang trong khai thac dau bang phUdng<br /> phap Cd hgc va tu phun (tieng Nga). Bao cao Hgp ddng LX-212A/SP-UNIOGAZ/11/95.<br /> 2. Vugovskol V. P., Tdng Canh San, Ha Van Bich, Le Oinh Hde, Phung Oinh Thuc. Problem restarting<br /> flow submarine pipeline, Proceedings of the International conference on engineering mechanics today.<br /> Vol.2,342-348;Hanol-1995.<br /> 3. Ha Van Bich, Vugovskol V.P., Tdng Canh San, Le Oinh Hde va Phung Oinh Thuc. Tdi uu hda qua trinh<br /> thu gom, xCr ly va van chuyen dau cac md Rdng va Bach Hd (tieng Nga), Bao cao de tai IV-6, Vien<br /> NCKH&TK dau khi bien, XNLD Vietsovpetro, Vung Tau, 2000.<br /> 4. Phung Oinh Thue, Ha van Bich, Tdng Canh Sdn. Van de van chuyen dau cac md Bach Hd va Rdng<br /> bang dudng dng ngam ngoai khai (tieng Nga). Tap ehi Dau khi/\zerbaizan., tr. 56-59, sd6, Bacu, 1999.<br /> <br /> <br /> <br /> <br /> 184<br />