THAM DO - KHAI T H A C D A U KHI CAC TINH CHAT CO HOC CUA OA XI M A N G TRAM GIE'NG KHOAN TRONG DIEU KIEN AP SUAT CAO, NHIET DO CAO BE NAM C O N SON ThS TrUtfng H o a i N a m Tdp dodn Ddu Viit Nam Email: rjamth@pvn.vn Tom tSt Be trdm tich Nam Cdn San cd dieu kien dia chdt rdt phdc tgp, ddc biet nhiet cao den 200'C vd gradient dp sudt via len den 2MPa/100m Ap sudt cao, nhiet cao (HPHT) tiem dn nhieu rdi ro vd phdc tgp qud trinh khoan vd trdm xi mdng gieng khoan - mdt nhdng cdng dogn cd tinh chdt quyet djnh din chdt lugng thi cdng vd an todn, Ket qud nghien cdu dnh hudng cua HTHP den cdc tinh chdt cahgc cua dd xi mdng Id casd quan trgng de thiet kedan pha che vda xi mdng trdm cde gieng khoan dgt hieu qud cao vd an todn TUkhda: VCfa xi mang trdm, dp sudt cao nhiet cao, silica 55A-i Gidi thieu g i l n g l i 172°C v i ap suit via 74MPa; tai gieng 05-1c-DN- Be Nam Cdn Sdn gdm cae dang ddi tUdng chda d i u va r l t da dang mdng ndt n l trude DeTam, c i t k i t Oligoeene tren va Miocene dUdl, c i t ket va ddi tuong carbonate tudi Miocene gida Ngoai ra, be Nam Cdn Son edn g i p cic he thdng dau v i khf cac dj thudng ap sua't eao, nhiet dp cao v i nam d viing nUde sau [11] Hien tupng HPHT dUpc p h i t hien khu vUe t r i m tich Cenozole thay doi tUTay sang Ddng cd be d i y 5.000-14.000m D i n nay, d be Nam Cdn Son da ed gan 100 gieng khoan tham dd, tham lupng va p h i t tnen khai thac Tai mdt sd gilng khoan, gradient ap suit dat 1,6MPa/100m 2X-ST2, d chieu sau 4.245m gap nhiet dd 185''C, i p suat via 98,7MPa; tai gilng 04'2-HT-1X d chieu sau 4.548in nhiet dp tren day gieng la 210°C va I p suit via 91 MPa [8, 9] Hinh the hien sU p h i n bd nhiet dp eie gieng khoan md Hal Thach v i i p suit day tai khu md MdcTinh Trong dieu kien ap suat cao va nhiet dp cao, viec thi edng gieng khoan tiem an nhilu rdi ro eho q u i trinh khoan va tram xi m i n g gieng khoan Trong gieng khoan cd ap suit va nhiet dp b i l n ddi Idn se lam tang Ung suit p h i vd dp dn djnh eda vanh da xi m i n g , lam bien dang cot dng chdng anh hadng den sU Hen ket cdt dng chdng vdl v i n h da xi m i n g va kha nang each ly eda d i xi mang Kit qua khoan tai be Nam Cdn Sdn cho thay viec (04-3A-1X, 04-3-MC-2X ); tham ehi cd gieng khoan gradient i p suit dat 1,9 - 2,04MPa/100m (04-1-ST-lX, sd dung cac phu gia vda xi m i n g chaa phu hdp vdl mdi 04-SDN-1X,05-2-HT-lX ).Tdchilu siu 2.500m trd xudng trudng gieng, dan den dp t h i m eua da xi mang tang x u l t hl^n khoang ap suit tang cad, ben dudi cic ddl dat d i tuoi Ap sua't (EMW-ppg) o » « » - Pliocene Khoang chinh gida ap suit via v l ap suit ndt via rat nhd (chi ppg) t i n g Miocene g i y khd khan cho cdng tac khoan va hoan thien gieng Tai b l Nam Cdn Sdn, da p h i t g § hien nhiet dp eao tai 25 gieng, | tap trung dia t i n g cd tuoi , g j a Z Miocene giufa va Miocene sdm Tai eic gieng 04-2-SB-1X va 04-2-NB-lX, nhiet °F dd tren d i y gieng dao ddng t d 135 - ' ,2» l y c C d chieu sau tCf 3.800 - 4.000m Hien tUdng i p suit cao, nhiet dp cao xuat hien tai gieng khoan 05-2-HT-2X, d chieu sau 3.740m nhiet tren d i y \ 24 DAUIIHI-SO12/201') (a) Hinh Bieu phdn lid nhiet (a) vd dp sudt (b) I8j (b) PETROVIETNAM Bang Bdi Phan cSp HP/HT _Ex-HP/HT_ "ultra HP/HT" in cap HPHT[71 Nhiet tren d a y gieng A p suat trSn diy gieng > O^OOpsi (69MPa) - S.OOOpsi (103MPa) _ ] ^ SOCF OSO'-C) - BSO'F ( X > SSO^F (175°C) - 400°F (200''C )" ^ IS^OOpsi (103MPa)^20.qoOpsiJ138MPa) >"400''F (200°C) > 20.000psi (138MPa) n h a n h t h e o t h d i g i a n , d p b i n eua da g i i m , sU lien ket gida da va cdt dng kem, gay ap suit cot dng; tai mdt sd gieng x u l t hien hien tupng vanh da xi mang bj b i l n dang, CO ngdt, nut vd Reservoir ConditiDn Hiln nganh dau khf chUa cd loai xi mang dupe tieu chuIn hda de tram xi mang cie gilng khoan HTHP Do dd, xi mang Portland G-APi van la loai xi mang dupe sd dung phd b i l n de tram gieng khoan sau Vi vay, nhat thiet p h i i bd sung phu gia ben nhiet, de tri v i n i n g cao dp ben v i g l i m tham cua da xi mang Cic k i t q u i nghien cdu va tdng hpp kinh nghiem ve i n h hudng eua HPHT den cae tfnh c h i t co hpc eda da xi mang eho phep thiet ke he vda xi mang phu hpp, gdp p h i n nang cao c h i t lupng va hieu q u i thi cdng cic gieng khoan tham dd, khai thac d i u khf tai be Nam Con Son Anh hUomg cua HPHT den ben nen cua he xi mang tram gieng khoan 2.1 Phdn cap dp sud't cao nhiet cao be Nam Con San Cie g i l n g HPHT dupe quy Udc la cic gieng ed nhiet dd ttnh tren d i y t d 1SCC v i ap suit via td 46MPa trd len Halliburton phan chia HPHT c l p (Bang 1) Cie dau hieu HTHP tai be Nam Cdn Son phan Idn tap trung dia t i n g tuoi Miocene sdm va Miocene gida, cd the p h i n loai cap (Hinh 2): Cap HP/HT: nhiet t d 150 - 175''C v i i p suit ti^ 69-103MPa; Cap ex-HP/HT: nhiet tU 175 - 200°C v i i p suit tren 103-138MPa 2.2 Anh hudng eda nhiit dd cao den dd xi mdng 2.2.1 Xi mang trdm giing khoan dau Hinh Bdng phdn cap HPHT cdc mo be Nam Con San [9] CjS ed van tdc thuy hda cao nhlt, tao dd b i n va tang nhanh ben thdi han ddng r i n sdm Thanh phan C^S ddng ran cham hdn se keo dai ddng r i n eda da xi mang C^A quyet djnh sU ngUng k i t ban d i u va tang nhanh dd ben thdi han ddng rIn sdm hoat tfnh thuy hda cao hdn Vai trd eua C^AF qua trinh ngUng ket gidng C^A, nhung phy thude nhieu vao nhiet dp va ehlt lupng phu gia nhiet dudi lOO^C sin pham thuy hda cua xi m i n g Portland la gel calcium silicate hydrate (C-S-H (ll) hoac CjSHj) va calcium hydroxide Ca(OH)^ Vda xi mang dat dp ben thdi gian tUdng ddi lau (tdvai den v i i nam) cho d i n dat dupe dp ben tdi han d nhiet tren 100 - ° ^ gel C-S-H biln doi dicalcium silicate hydrate (a-C^S {C^SH(A) v i xi m i n g dat den dp ben cue dai vai t u l n d i u tien v i sau dd dp ben g i i m dan D i y la hien tuong b i l n ddl hinh thai cau true tinh the cua xi mang va dupc gpi la sU suy giam dp ben (strength retrogression) Khi nhiet dp > leO^C, C-H-S chuyen y-hydrate C^SH (C^SH(C)) va nhiet dp < 202''C, C-S-H tao CjS cd edng thde day du la Cag{Sip,)(OH)^ thay ddl cac Xi mang Portland mac G la loai xi mang dUOc sd tinh ehlt ly - hda va cP hpc [3] dung chu y l u de t r i m c i c g i l n g khoan siu ed phdi hpp vdi cac phu gia khac Thanh phan eua xi mang Portland Nhiet dp tang khien dp t h i i nude tang, sdc ben nen gdm: 3CaO.S10j (C^S) c h i l m 50 - 70%; 2CaO.SiO^ (C^S) cua xi m i n g giam va dp tham tang, I n h hddng den chat chiem 15 - 30%; SCaO-AI^O^ ( C / ) chiem - 10%; lapng t r i m gieng, g i i m tuoi thp, de gay phdc tap 4CaO-Alj03-Fej03 ( C / F ) c h i l m - 15%; CaS0^2H,0 qua trinh khai thac (CSH^) chiem - % [1,4, 5] DAU KHi SO 12/2014 THAM DO - KHAI THAC DAU KHI 2.2.2 Bien phdp ehong suy thoai ben cua v i n h d i xl mang, d i m b i o k h i nang gia cd va dp kfn Viec bd sung silica vao xi mang cho phep tao pha xi ming g i i u silica gidng nhU tobermorite va xonollte, tang dp ben nhiet, tri chat lUpng cua xi mang va ngin ehan suy giam dp ben Giii p h i p dUPe ap dyng td nam 1950 va den da trd tieu chuIn cdng nghiep [3,10] Silica la phy gia ben nhiet dupe sd dung he khoing khdng vanh xuyen Trong d i l u kien binh thUdng, xi mang cd dp ben nen 3,5MPa cd t h i xem nhd thda man eho edng t i e tram xi mang.Trong eic g i l n g khoan HPHT, cac dng suit ludn b i l n ddi cic t i c ddng co hoc, ap suat va nhl&t dp thay ddi theo ehe dp khai thic SUthay ddi cac dieu kien gieng khoan lam phat sinh cac Ung suit p h i vd sUdn djnh cua vanh da xi mang ngoai cot vda xi mang tram gieng khoan gdm: cat thach anh, dupe dng chdng Cie dng suit kiln tao va sU b i l n ddi ve i p suit nghien dat ed hat td 175 - 200mm; bdt silica (silica flour) ed hoic nhiet dp g i l n g khoan cd the lam ran ndt vinh cd hat 200-300 mesh; silica sieu (silica fume) - phu gia da va sut lun DUdng kinh cdt dng chdng bj b i l n dang sieu phan t i n td pha khi nung hop kim silica, cd ham t i c ddng eda sU b i l n ddi nhiet dp va i p suit ed the pha vd lUdng eao cic silica vd dinh hinh; nanoslllca cd kich thUde sU dfnh k i t eua vanh d i xi mang vdi cdt dng chdng hoac nhd hdn cie hat xi ming trung binh 1.000 l i n , thudng sd tangehUa, t a o t h a n h c a c k h e h d v i m d [ , , ] dung cd hat loai td - 50nm v i loai tU - 30nm [5] 2.3.2 Thiet kehi vda xi mdng trdm giing khoan De tram gilng khoan ed nhiet cao tren t h i m lyc dja Viet Nam mdt sd nha thau khoan nhU: Now/sco, Dow/ell/ Thanh phan chd y l u eua he vda xi mang cho gilng Schlumberger, Demitsu/Schlumberger, BJ, Halliburton da khoan dieu kien HPHT be Nam Cdn Son gdm: xi sd dyng silica vdi ham luong 35% hdn hop tram m i n g nen, chat tang trong, phu gia ben nhiet, nude trdn gieng.Theo nghien cdu [4, 5], viec bo sung 40% oxide silic va eic phu gia cham ddng ket, g i i m dp t h i l nude, cac l i chua du de b i o d i m dat dp ben eda d i xi ming thdng sd lUu bien, chdng t h i m , phy gia gia cudng cotinh cie gieng khoan ed nhiet dp tren 500°F hoic cao hdn eua da xi mang Tren eP sd tdng k i t he vijfa xl mang sii De xac dinh ham lUpng silica tdi Uu d i n cae tfnh ehat cP hpc eda vinh d i xi mang gieng khoan dieu kien ap suit cao, nhiet eao tai be Nam Cdn Son, t i e g i i da tien hanh nghien cdu i n h hudng nhiet dp eac cap khae Ket q u i cho thay viec sddung silica nhan hieu SSA-1 ™ de bo dung cho eie gieng da khoan tai Ld 05-2 va 05-3 [8], tac g i l de xuat edng thde, phin, h i m luong vat lieu, phu gia eho he vda xi m i n g t r i m gilng khoan HPHT be Nam Cdn Son {Bing 2) 2.3.3 Thiet bl do ben dd xi mang bdng sieu am (UCA) sung cho hdn hpp xi ming tram dem lai hieu q u i cao [8,9] SSA-1™ (silica flour) la loai oxide silie ket tinh, mdt loai phy gia b i n nhiet Halliburton sin suit SSA-1™ ed khdl lupng rieng: 2,60 - 2,63g/em^; cd hat 200 - 300 mesh (35%), 100 - 200 mesh (8%) va > 100 (0,2%), va ehpn t^ le 35% theo khdi lupng eda xl mang nen Tie gia xie djnh 66 b i n cua d l xi mang bing thiet bj sieu am - UCA {Hinh 3) Nguyen ly hoat ddng eua UCA dUa tren sU Hen ket gida thdi gian tin hieu sieu i m xuyen qua v i dp ben nen eua mau d i xi m i n g bang sU pha hCiy dudi t i c ddng eda t i l trpng eo hpe (Hinh 4) Trong dd,"d6 ben I m hpc" la mde dp phat t r i l n dd ben cua mau da xl 2.3 Anh hudng eua HPHT den dd ben nen mang va trUc tiep van tdc I m xuyen qua miu."Op ben nen"dupc trdc tiep va xie djnh bdi lgc can t h i l t de pha 2.3.1 D6 bin n4n huy mau d l xi mang Hai trj sd dope xie djnh cCing Trong thi edng tram xi mang gilng khoan dau khf, gia dieu kien, nhung vdi phuong phap khac nhau, trj sd tuyft trj dp ben nen l i ehi tieu nhat de d i n h gia tinh chat ddi khdng n h i t t h i l t gidng l/u diem cua UCA l i c6 Bdng Bon chebexi mdng gieng ichoan HPHT be Nom Con Sm ! ThUcmg pham Holcim Class G Silica SSA-1, SSA-2 HiDENSE K4 (FeTiOj WellLife987(PB) Microbond HT SCR-25L " Halad-431L Nudc ky thuat f 26 DiillKHi-SO 12/2014 Dofn vj %kL %kL %kL"" %kL %kL gps _ gps gps ' : Ham lutfng 100 35 " 40 "" _ 0,25 0,50 16" Cong dung Xi mang nln Phygia ben nhiet P^y-Q'^^sng trpng Phu gia tang ben Phyjiagiannd ~ Cham ngirng ket Phu gia giim thii nudc Nudctron PETROVIETNAM the quan s i t sU phat tnen dd ben theo thdi gian, da b i o thdi gian chd ddng ran xi m i n g , xae djnh dp ben dieu kien HPHT 2.3.4 Ket qud thi nghiem Bing tong hpp cae k i t q u i thf nghiem ve I n h hudng cua HPHT den quanh eda vda xi m i n g vdi ham luong 35% silica SSA-1 A™ [8] Bd sung phu gia HR-25L v i CFR-3L la g l i i phap ehd y l u v i hieu q u i de tri va ell thien cae tfnh ehlt cdng nghe eua xi mang: tang thdi gian q u i n h cua viJfa xi mang dat trj sd lOOBc (dp q u i n h Bearden) khoing - gid, dam b i o an toan thdi gian bom ep; lam cham thdi gian ngUng ket cua vda xl mang; ngan ngda sU suy thoai dp b i n cCia xi mang va nang cao cic tfnh chit co hpe eda vanh d i xi mang d nhiet dp tren day gieng khoan (140-180°C) Phy gia tang trpng Hi-Dense dUdc sin x u l t td nguyen lieu khoang hematite, khong nhiem td, khdng chda phdng xa dap dng cac yeu cau chit lam nang nhd dp p h i n tan cao, bao d i m dp dn dinh (khdng lang dpng) cua vUa.Trong phu gia chda cic oxide sat cd t h i tao cac hydration ferret v i alumoferit dd ben eao, on djnh Hinf} Sado nguyin if ldm viiccua UCA Bdng Tong hap edcketgud thi nghiem vesu dnh hudng cua HPtiJden thai gian quanh eda he vSa trdm gieng khoan Dien g i i i Xi mang Holcim G Chat on djnh ben-SSA-1 jChat tSng trpng - Hidense-4 Chat tSng MicroMax FF ,g Chat gian nd Microbond HT E 'ChattangcOtfnh-WellLife897 , % kL %kL % kL % kL % kL %J(L ,g SA-1015(PB) _ _'^^^ c iTang ben k4o F^P-C765_ r %kL •c^ Chat chdng tao bot - D-A|r 4000L gps •= , Chat giam dp thai nUdc Halad-413 gps t Ic 'Phu gia cham ngiing ket-HR-25L gps Phy gia cham ngUng ket SCR-100 gps j I Phu gia pha loang-CFR-3L gps_ Nudc trdri gps Mat d6 vQa Nhiet dp thi nghiem „g Ap suit thf nghi#m Mau vCa xi mang Don vi A B_ C _ D(6P)_ E(6P) F G H I , 1100,00 1100,00 100,00' 100,00 100,00' 100,00' 100,00' 100,00 ' 100,00 ' 100,00 35,00 0,05^ 0,50 0,05 0,25 ' 5,19_ 15,80_' 190 5,482 II 7h55' I gid, phut ! gid, phut ' 7h57' 6h56' 35,00 3,00 7,00 3,00 0,70 0,05 0,50 0,40 0,29 0,20 0.70 0,30 0,20 5,35 4,46 15,80 17,00 i 239 7,005 , 8,601 15 jDpqu^nh30Bc 35,00 35,00 0,05 0,55 g |Pp quinh 50Bc 52 35,00 • 7,00 0,70 0,05 0,04 35,00 40,00 25,00 3,00 7,00 0,15 1,00 0,10 0,50 0.02 0,30 5,18 7,97 16,00 17,00 230 7,324 34 , 8h29' 27 35,00 35,00 35,00 40,00 40,00 40,00 25,00 ^5,00 ^5,00 3,00 3,00 3,00 7,00 7,00 7,00 0,10 0,10 0,10 1,00 I 1,00 1,00 0,10 0,10 0,10 0,50 0,50 ' 0,50 0,27 0,27 0,26 _0,22 0,26 0,90 0,90 0,90 7,97 481 4,81 17,00 18,50 18,50 257 302 9,624 12,900 12,900 27 35,00 40,00 25,00 _3,00 ' 7,00 0,10 I' 1,00 '' 0,10 0,50 ^ 0,27 0,26 • 0,90 481 18,50 302 12,900, 8h48' 7h" 8h50' 5h59' 8h05' _8h53' 8h48' 8h52- 7h37' 7h39' 5h38' 8h30' I gid, phut ! 8h15' 7h7' 8h54 8h00' 8h08' 8h53' 7h46' 5h42' 8h35' gid, phut l£ Dd quinh lOOBc^ 35,00 0,10 10,05 pgp I 13,50 190 "F _ psi _ 5,382 £ Dp quinh ban dau 35,00 8h7' 8h43' 7h43' 8h52' 8h53' OAUHHl-S012/2014 27 "^' P THAM DO - KHAI THAC DAU KHI ehat lUu via, eho phep ning eao dp ben nen eda da xi mang, gilm ham lupng the tfch, nhd dd g i i m dupc trj sd dp nhdt Dp ben nen cua da xi mang eic dieu kien ap suit va nhiet khac dupe the hien Hinh - DUdng mau lam - the hiln sU phat trien dp ben nen; dudng mau xanh - nhiet va dudng mau dd - thdi gian truyen sdng i m tren mdt don vj khoing each.Trj soap suit d i t UCA va khdng the hien tren bieu Trong Bieu dd sa p h i t trien dp ben nen cua d i xi mang cd mat vda 15,80ppg (Hinh 5), nhiet tang tU80 - 237''F {26,7 -114=0 va ap suit 20,67MPa Dp ben tdi thieu cua gel bang SOpsi (0,34MPa) thdi gian gid 49 phut; lOOpsi - gid 56 phut; I.OOOpsi - gid 12 phut; 916psi - gid v i 1.698psi -12 gid; ben nen cue dai b i n g 1.780psi -13 gid, sau dd gilm dan dat SOOpsi khoang 22 gid Hinh the hien ben nen theo thdi gian cCia d i XI ming cd mat dp vda 15,8ppg, nhiet dp td 80 - 266''F (26,7 - ISO^C) v i i p suit 3.000psi Quan sit cho thay dp ben nen tang d i n : SOpsi gid phut; 100psi-5gid 10 phut; SOOpsi - gid 59 phut; 859psi - 12 gid; 860psl - 24 gid; OOOpsi - 29 gid 35 phut; 2,681 psi-48 gid Hinh Bieu dodo ben nen cdo ddxi mang dudi dp sudi OOOpsi vd nhiet 266'F(13KH020 Momepuana BypeHwe M He(|)Tb-/leKa6pb Energy Science and Technology 2012; 4(2): p 36 - 60 2011 BP Vietnam Final Well Report {HT-1X; 2X; 3X) 2003 12 Nguyen Giao, NguyenTrpngTfn Bitrdm tich Nam Con San va tdi nguyen ddu Dja chat v i Til nguyen Diu Halliburton Vietnam Cement Post Well Review (MT-2X, MT-1R MT 6P, MT 3P) 2012 khf Viet Nam Nha xuat ban Khoa hoe va Ky thuat 2008: trang319-359 Mechanical properties of cement bond of weilbore in high pressure Inigh temperature conditions of Nam Con Son basin Truong Hoai Nam Vietnam Oil and Gas Croup Summary The Nam Con Son basin has a greatly complicated geology, particularly temperature as high as 200'C and the reservoir pressure gradient up to 2MPa/100m A high pressure high temperature (HPHT) environment contains many potential risks and complexity for drilling and cementing job, which is critical to the v/ell quality and safety The results of studying the effects of HPHT on the mechanical properties of the cement bond will be the important basis to prepare cementing formula with high efficiency and safety for the high pressure high temperature wells in the Nam Con Son basin Key words: Cementing slurry, high pressure high temperature Silica SSA-1 ... Thiet kehi vda xi mdng trdm giing khoan De tram gilng khoan ed nhiet cao tren t h i m lyc dja Viet Nam mdt sd nha thau khoan nhU: Now/sco, Dow/ell/ Thanh phan chd y l u eua he vda xi mang cho gilng... 103-138MPa 2.2 Anh hudng eda nhiit dd cao den dd xi mdng 2.2.1 Xi mang trdm giing khoan dau Hinh Bdng phdn cap HPHT cdc mo be Nam Con San [9] CjS ed van tdc thuy hda cao nhlt, tao dd b i n va tang nhanh... gia eho he vda xi m i n g t r i m gilng khoan HPHT be Nam Cdn Son {Bing 2) 2.3.3 Thiet bl do ben dd xi mang bdng sieu am (UCA) sung cho hdn hpp xi ming tram dem lai hieu q u i cao [8,9] SSA-1™