PETROVIETNAM
GIAI PHAP CONG NGHE N A N G CAO THU HOI DAU CAC MO NGOAl KHOI
ThS. TrUomg Dure Trpng, TS. Hoang Thjnh Nhan Dai hoc Ddu khi Viet Nam
T6m t i t
Hogt ddng thdm dd, khai thdc ddu khitrin biin b6t ddu phdt triin tCf nhCfng ndm 1950 vd ngdy cdng trdnin sdi ddng vdi sUtham gia mgnh mi cua cdc cdng ty ddu khi hdng ddu thi gidi. Tinh din ndm 2010, trUIUdng cdc vung khai thdc ddu md ngodi khai dgt khodng 650 ty thung ddu quy doi (Cboe), chiim 20% tong trUIUdng ddu md dd dUdc xdc minh 11}. Tuy nhiin, thdm dd, khai thdc ddu khitrin biin doi hdi cdng nghi rdtphdc tgp, trong dd qud trinh khai thdc, dUa ddu lin hi thdng xCtly vd phdn tdch chiu dnh hUdng bdi nhiiu yiu tdnhU: dp sau mUc nUdc biin, tinh chdt cua lUu chdt (dd nhdt, ty trpng, thdnh phdn tgp chdt) vd cua via chUa (nhiet dd, dp sudt...). Bdi bdo ndy gidi thieu cdng nghi hdt vd xCfly ngdm (Subsea Boosting and Processing - SBP), mdt hUdng di mdi dang dUdc nghien cUu vd phdt triin Ung dung dindng cao hieu qud khai thdc, qua dd giup ndng cao hi sd thu hdi ddu tgi cdc md ngodi khdi, ddc biet ddi vdi cdc md ddu cd t^ trpng ddu cao vd/hodc dp sudt via thdp.
1. Gidi thiiu cdng nghe SBP
SBP l i t6 hpp cdng nghi phin tich hdn hpp dau khi, bom da pha v i nen khf tren be mat day bien. Ddng sin phim sau khi qua h$ thdng SBP dupc dua len gian thu gom xil ly trung t i m (host platform) hoic cd the dua thing true t i i p v i bd thdng qua h§ thdng dudng ong.
Oiy l i mdt cdng nghe mdi, da v i dang dupe i p dung cho mdt sd du i n Idn tren t h i gidi, nhu md Marlim (Brazil) cua Petrobras, md Tordis (Na Uy) cua Statoil, md Pazflor (Angola) cua Total, md Perdido (vinh Mexico) cua Shell.
Mdt sd t§n tudi Idn cac nhi cung cap cdng nghe SBP phii k i d i n FMC Technologies, Cameron, ABB Veteo Gray, Aker Kvaener Subsea, Schlumberger va Baker Hughes.
Uu diim rd r&t nhit khi sCf dung cdng nghe SBP la giim chi phf mua thiet bj xCf ly va nen khi tren he thdng xCr ly n6i, ting h$ sd thu hdi dau, t i n g sin lupng khai thac [5].
X6t trin khia canh thu hdi dau ting cUdng (improved oil recovery - lOR), SBP l i mdt trong nhUng phuong phap day triin vpng trong tuong lai v i theo dinh gia cua Tap ehf Offshore Technology, den nim 2015, nganh cdng nghiep subsea se cd g i i trj 43,4 ty USD trong dd SBP la cdng nghe triin vpng diy t i i m ning nhit [6].
Cdng ngh^ SBP gom 3 nhdm thiet bj chfnh: Bom t i n g i p ngim (subsea pumping units - SPU), thiet bi xCf ly ngim (subsea separation units - SSU) v i thiet bi nen khi ngim (subsea compression units - SCU). Trong dd, SCU c6n dang trong giai doan phit trien phdi thai va hien nay chila cd du i n nio tren t h i gidi i p dung phuong phip niy. Tuy nhi^n, ke hoach phit triin SCU van dang dupe
trien khai, vdi dU i n thf diem tai md Ormen Lange (Bien Bic) cua Statoil vdi hy vpng khf se dupe nen tai day bien va di'y true tiep vio bd cich dd 120km vao nim 2015 [6].
Do do hien nay SPU va SSU l i nhCfng thiet bj chu yeu cho cdng nghe SBRTuy vao dieu kien cua md cung nhU die tfnh cua hon hpp dau - khf - nUdc ma ngUdi ta xem xet viec lap dat SPU hoic SSU.
1.1. Bum tdng dp ngdm - SPU
Nam 1992 dinh dau viec sCf dung SPU cho md Prezioso (Italia) nhim bu dip tdn hao i p suit nhanh trong qui trlnh khai thac, tang ap suit de di'y dau len thiet bj ndi be mat, tuy nhien dU i n chi mdi mang tfnh chat thCf nghiem, chUa dip Ung dupe cac yeu ciu ve thuong mai [7]. TU dd den nay, rat nhieu dU an ting cudng he sd thu hdi diu sCf dung SPU d i duac trien khai nhu dU i n BP ETAP, Topacio, Ceiba,BPSehiehallion,Tordis... [6].
DUa theo giin 66 ap suit - lUu lupng (Hinh 1), cd the thay trong trUdng hpp lap d i t SPU, dudng cong i p suit - luu lupng se dich chuyen len phfa tren do hon hpp dau khf dupe cung cap mdt lupng ap suit du Idn. Oudng cong nay giao vdi dudng cong he thdng (dac trung cho tUng gieng) tai diu thi dd chinh l i sin lupng mdi sau khi lip dat SPU [8].
Ve CO che hoat ddng, SPU tuong tU nhU cac he thdng bom d i u hoic nUde khic, hdn hpp chit Idng se nhin dupe ning lupng tU may bom v i di chuyen tU diy bien len he thdng xCf ly trung t i m tren be mat. Tuy nhien, hdn hpp chit Idng tU mieng gieng len la hdn hpp chUa qua xCf
Diu Wli-so 3/2013 29
Ty I? khi trong liAj chSt (%)
Hinh 2. Mien Ong dung cua cdc logi bam tdng dp ngdm
ly, g o m nhieu tap c h i t va nhieu pha, do d d c i n p h i i ed thiet ke d i e biet de han che i n mdn, m i i mdn v i gia tang tudi tho cua m i y b o m khi lam viec dUdi dieu kien nhiet dp va i p s u i t bien thien Idn. Ve chUe nang, b o m tang i p n g i m cd ba loai chinh: b o m don pha (single phase p u m p - 5PP), bom da pha (multi phase p u m p - MPP) va bom hybrid. Trong b o m da pha MPP cd bom da pha cao i p (high boost MPP) ed the tao dupe ap s u i t Idn g i p 4 l i n so vdi MPP thudng. Hinh 2 the hien Ung dung cua tUng loai b o m cho tUng dieu kien t h i n h phan ty le khi trong lUu c h i t (gas volurrw fraction - GVF) v i i p s u i t c i n thiet [9].
Hinh 2 cho thay, b o m SPP ed the tao ra i p suit cao nhat (tdi da len den tren 250 bar), tuy nhien GVF chi gidi han dudi mUc 10%. Bom MPP thudng hoat ddng trong mien 0 - 9 5 % GVF v i tao ra i p suit k h o i n g tren dudi 50 bar. Bom da pha cao i p (mau xanh nhat), cd the tao ra i p suit tdi 200 bar, tuy nhiifl bi gidi han hoat ddng trong k h o i n g 20 - 95%. Bom Hybrid cd the hoat ddng tdt trong mien 0 - 3 8 % GV|
va tao ra i p s u i t tdi da tuong dUong vdi da pha c ^ i p . Thiet bj nen khf udt (wet gas compressor - WGQ (phan m i u v i n g ) thudc ve cdng nghe SCU.
Trong thiet ke b o m da pha thudng v i da pha cao i p , ed hai thiet ke chu yeu l i : thiet ke rupt ^ ddi (twin-screw p u m p - TSP) v i thiet ke true xoin Bdng 1. So sdnh giOa bam TSP vd bam HAP [10]
Thiet ke ruot ga doi (Dong chiy tjnh tien)
Thiet ke true x o i n (Dong chiy doc true)
, H& so the tich khi
; (GVF)t6ida I Ap suat tao ra
Cdng suat Ap suit toi thieu j tai dau hut J 0 6 nhdt luu chat
\ Ap suat l^m viec j Thiet ke lip dat
1. Bornemann: chii yeu cung cap thiet bj tren bd va ngoai khoi, c6 2 dif an lip dat subsea (2005, 2007);
2. Leistritz: chu yeu cung cap thiet bi tren bd va ngoai khoi, CO 1 du an lip dat subsea (2010);
3. GE Oil & Gas: cung cap thiet bi subsea;
4. Flowserve: cung cap thiet bi tren bd va ngoai khoi.
100% (khi ket hpp ciing vdi he thong tai sUdung luu chat)'
T6ida100bar(1.450psi)' Toi da 1.200.000 thung/ngay' Ap suit khi quyen'
:i
1. Framo: chu yeu cung cap thiet bj subsea v i c i tren bd va ngoai khoi, da co 15 du i n lip dat subsea;
2. Sulzer: cung cap thiet bj tren bd va ngoai khoi.
100% (khi ket hop cung vdi thiet bj loc hoac thiit bi khuay)^
Toi da 200 bar (~ 2.900psi), thay d6i theo GVF va I dieu kien hut^
Toi da 450.000 thiing/ngay^
40psi^
MUc thap: 0,55cp (da kiem chUng)"
MUc cao: chua xac dinh 5.000psi^
Lip dat ngang (thiet ke lip dat dUng dang trong qua Lip dat dOng (subsea) ho3c lip d§t ngang (tren trinh phat trien) Q*^") ,^
MUc thap: 2cp (da kiem chUng)' MUc cao: 4.000cp (da kiim chUng)' 15.000psi^
Ghl chu:' Theo Bornemann (httpJ/www.bornemann.com/multipho$e-boosting-teehnology):'Theo niin gidm cua Framo; > Theo Framo (httpy/www.framoeng.no/page/207/framo-mult,phase-pump-hx);'TheoSaadawiandAIOhma(2003):'TheoDav,svdnnk(2009)
PETROVIETNAM
(helico-axial pump - HAP). Ngoii ra cdn cd bom ly t i m diin ngim (electrical submersible pump - ESP), tuy nhien do khi nang han che cua loai bom nay khi bom hon hop diu cd ty trpng cao, ngudi ta thudng phii xCf ly hdn hpp diu trudc khi dua qua ESP. Cfng dung cua ESP se dupc md t i tai muc 1.2. Do dd vdi muc dich bOm t i n g ap ngim, ngudi ta chu yeu stf dung TSP v i HAR Ci hai thiet ke nay d i u cd the xCf 1;^ luu chit vdi GVF bien thien Idn (tUO - 95%, tdi da den 100%). Bing 1 t h i hiSn sU so sinh giufa hai loai thiit k i cho bom da pha tang i p ngim theo mdt sd tieu chi chfnh.
Tii k i t q u i so sinh cho thiy cdng suit hoat ddng cua TSP hon hin HAP (1.200.000 thung/ngiy so vdi 450.000 thijng/ngiy), song vdi cic ti§u chi khic (dp nhdt cua d i u
Hlnh 4. Sa dd Idp dgt hi thong SSU [12]
cd the xii ly, i p suit chenh lech tdi da) thi HAP vUpt trdi hon TSR Vdi muc dich khai thic ngim thi HAP dupe i p dung nhiiu hon TSP do khi nang van hanh tdt hon v i da dupc kiem chufng qua nhieu dUin. Nhi sin xuat HAP Idn nhit l i Framo Engineering d i va dang phit trien he thdng bom ting i p ngim tich hpp them chufc nang do dac kiem soit luu lupng lUu chit tU cic gieng, gpi la framo dual pump station - FDS cdng suit vUpt trdi so vdi HAP binh thudng. Hinh 3 minh hpa so dd lip d i t mdt FDS cho mdt md dang khai thic.
Theo Hinh 3, FDS trdng gidng nhU mdt cum phin ddng ngim, cd chUc nang tiep nhin luu chit tCr cic gieng, do dac luu lupng va xic ^ n h cic tinh chit cua lUu chit, bom nguoc len thiit bj xCf ly ndi tren be m i t bien. Phuong thufe lip d i t FDS, k i t ndi thiet bi vdi he thdng dudng ong va khai thic ngim, cich thufe lip d i t che dp theo ddi v i kiem soit FDS khdng nim trong pham vi bii Viet nay.
Bom hybrid l i sU cii tien cdng nghd, k i t hpp hai kieu thiet ke TSP v i HAR de d i p ufng mdt sd yeu ciu khai thac die biet (ip suit cin tao ra cao, dp nhdt cua diu cao, GVF Idn) d i dupe tien hinh lip d i t cho md Pazfor (Angola) ciia Total [11].
1.2. Thiit bixdly ngdm - SSU Thiet bj xCf ly ngim hay thiet bi phin tich ngim - SSU cd chufc ning tich hon hpp d i u khi da pha thanh cic pha rieng biet. Ve CO che hoat dpng, SSU tuong tU nhu cic thiet bj phan tich tren eae he thdng xCf ly noi, hdn hpp d i u khi dupc phan tich trong thiet bi dUa tren nguyen ly phin tich bing trong luc. Do cic SSU dupc lip dudi diy bien, vi viy he thdng x i khi de ddt nhu tren mat bien l i khdng cd. Ngoai ra, phin tich hdn hpp d i u khi dudi day bien chi cd the phin tich hai pha thay vi ba pha nhutren mat bien, dd la: phin taeh pha Idng v i pha khi (liquid/gas SSU) v i phin tich
OikU K H i - s o 3/2013 31
nude v i diu (oil/water SSU). Hinh 4 minh hpa so do lip dit thiet bi SSU.
1.3. Phdn tdch pha Idng vd pha khi Khi sau khi dupe tich se dupe dua thing l§n giin xCf ly trung t i m qua mdt 16 thdng v i he thdng ong dan bing phuang phip tU nhi^n do bin thin khi sau khi tich niy tdn tai ning lupng ben trong nd (Hinh 5). Hon hpp chat Idng sau khi tich se bao gom diu v i nude se dupe day len bdi mdt bom dien ly t i m ngim (electrical submersible pump - ESP).
Nhu thiet k i trong hlnh, bom ESP dupe thiet k i dit trong thiet bi phin tich dUng (vertical annular subsea separation) ed nhiem vu bom hdn hpp dau v i nude qua mdt dudng ong rieng. Ngoii thiet ke va d i p va phin tich bing trpng lUc, trong mdt sd trudng hpp, ngUdi ta lip dat them mdt sd thiet bj nhim lim ting khi ning phan tich hdn hpp luu chat nhu lip hydrocyclone de loai bd cit, thiet ke cic dudng xoin de ben trong SSU de tang khi nang tich khi v i chit Idng.
Trong thiet ke binh phin tich pha Idng v i pha khi, thudng i p dung dinh luit Stoke de tinh toin van tdc ling cOa chit Idng trong hon hpp luu chit [14]:
Hinh 5. Sa do vdn hdnh hi thong SSU kit hop bam ESP [13]
A.g.DlPrPg
3.Co (Eq-D
Trong dd:
V,: Van tdc ling cua gipt chat Idng (m/s);
g: Gia tdc trpng trudng (9,81 m/s^);
D: Oudng kinh eua gipt chat Idng (m);
Cj,: He sd keo;
p, :Ty trpng cua chit Idng (g/l);
Pg: Ty trpng eua khi (g/l).
Vin tdc ling cing cao, thdi gian de pha khi tach khdi pha Idng cing nhanh. Theo phuong trinh Eq-1, ed the thiy dudng kinh eua gipt chat Idng cing Idn hoic he sd kio cing thip thi van tdc ling se cang Idn. Oe dat dupe dudng kinh tdi uu eua chat Idng trudc khi tich khdi hdn hpp lUu chit v i ling xudng diy binh phin tich, ed the thiit k i th§m mdt sd bd phin ben trong binh phin tich nhuthiet ke t i m tich tu - coalescing plate nhim tich tu cic gipt nhd thinh gipt Idn [14]. He sd keo C^ phu thudc vio h i sd Reynold duoc tinh theo cdng thufe sau:
Re Re
(Eq-2)
He sd Reynold ty le nghich vdi dp nhdt cua lUu chJt Vi the, hdn hpp lUu chat cang nhdt thi he sd k^o cing ^., toe dp ling cua chat Idng cang giim. ™
Viec lip d i t eae Liquid/Gas SSU ma tieu bieu la VASP tang ding ke hieu suit thu hdi diu, nhu tai md Marimba (Brazil), trUde va sau khi l i p d i t VASR sin luong khai thac dau tang tii 35.000 thung/ngiy len 44.000 thung/ngiy, ting khoing 25,7% [13]. Oac biet, trUdc khi lip dat VASP, de dat dupe sin lupng 35.000 thung/ngiy cin phii ip dung phuang phip bom ep khi, nhUng sau khi lip dat VASR sin lUpng dat 44.000 thung/ngiy m i khdng cin siJ dung phuang phip bom ep khf.
1.4. Phdn tdch ddu vd nUdc
Thiet bj phin tach dau v i nUde cho phep tich nUdc ra khdi hdn hpp d i u va khi. H6n hpp d i u v i khi se tiep tuc dupe day len de xii ly tiep tren mat bien bang mdt bom da pha ngim. Viec k i t hpp stf dung giufa thiet bi phin tich va thiet bj dung cho muc dich bom dang l i xu hUdng eua the gidi khi i p dung cdng nghe SBR Bing cich k i t hpp niy, hieu suit thu hdi dau se dupe ting len ding ke v i mat \j thuyet. NUde sau khi tich ed the dupe dung de bom ep via neu dat chit lupng theo y§u ciu bom ep cua tiTng via.
Hdn hpp d i u v i khf se dupc bOm len giin xCf ly d i phin tich tiep. Luc nay, thiet bj phin tich tren giin trung tim se don giin hon do chi yeu ciu phin tich hai pha, tU dd dan den tiet ki^m chi phi cua d u i n . Hinh 6 md t i he thdng phin tich ngim hai pha nUdc v i diu.
32
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Dudng khf phy ^
Hinh 6. Sadd md td hi thong phdn tdch ngdm pha ddu vd nudc [12]
Cdng nghe ket hpp nay dang dupe sCf dung ngiy mdt nhiiu v i cho kit q u i rat khi quan. Sau khi i p dung cdng nghf SBR dU kien mdTyrihans (Na Uy) eua Statoil - Hydro se ting sin lupng khai thac len 10%; md King (vinh Mexico) cua BP se ting sin lupng khai thic len 20% va he suit thu hdi ting 7%; md Tordis (Bien Bic) cua Statoil se ting h^ sd thu hdi tif 49% len 55%.
Odi vdi thiet ke SSU de tich dau va nudc, ngoai kfch thudc, kiiu ding, thiet bj ben trong... thi toe dp ling eua nude so vdi d i u rat dupc quan t i m , thdng thudng dupe tinh theo cdng thufe [15]:
-S¥^)
(Eq-3)Trong dd:
V^: Van tdc ling cua nUde via (m/s);
g: Gia tdc trpng trUdng (9,81 m/s^);
D: Oudng kinh cua gipt nUdc (m);
Cp: H i sd k^o;
p,,,: Ty trpng cua nude via (g/l);
P„ :Ty trpng cua d i u (g/l).
He sd keo C^ tfnh toin dua theo cdng thUe Eq-2 nhung don gian hon [14]:
C D = — (Eq-4) 24
Re 2. CTng dung cdng nghe SBP
Bang 2 tdm tat thdng tin mot sd md tieu bieu tren the gidi da va dang i p dung mdt phan hoac toan bd cdng nghe SBR Viec Ung dung giai phip cdng nghe niy da dem lai nhUng ket qua cu the nhU: giim chi phi CAPEX v i OPEX, tang sin lupng khai thac, nang cao he sd thu hdi diu, ting dim bio ddng chiy va dd ben he thdng khai thic v i van chuyen ngim.
Cdng nghe SBP dupe xem la mdt giii phap giup nang cao thu hdi dau cho cac md ngoai khoi dang khai thac (sin lupng khai thac sut giim, mUc dp ngap nudc tang, he thdng noi han che) cung nhu cho phep phat trien cic md mdi (dau ed ty trpng cao, ap suit thap, hydrate khi).
Odi vdi Viet Nam, cdng tic tham dd, khai thic dau khf ngoii khoi hien nay dang gap mdt sd thach thUc: i p suit via trong khoing trung blnh va thap, giy khd khin trong viec dua sin pham khai thac len he thdng xCf ly ndi; nhiet dp lUu chat thap, lam cho khi nang hydrate khi ting, giy bit dudng ong dan luu chat tU mieng gieng len he thdng xd ly va dudng dng van chuyen; sU xim thue eua nudc sau mdt thdi gian khai thac; sU sut giam ap suit day gieng sau mdt thdi gian khai thic. Do do, cdng nghe SBP la mdt trong nhtjfng hudng di mdi giup giii quyet cic van de ky thuit tren trong qua trinh khai thic dau khf bien, cho phep nang cao he so thu hdi dau, gia tang sin lupng khai thic cung nhU hieu qua dau tU, tan thu ngudn tai nguyen quy gia trong Idng dat.
Tuy nhien, khi nghien cufu Ung dung cdng nghe SBP cho tUng du i n cu the can can nhac cic van de sau:
- Op tin cay cua eae thiet bj SBP: do SBP d i t dUdi diy bien v i van hanh tU ddng, khi ning kiem soit tU bd hay tUtren giin xCfly, cung nhuvieebaotrl sebi han che.
Bdng 2. Cdc md trin the gidi dp dung cdng nghi SBP trong khai thdc Ovr^n/Oiadiim
Pazflor/Anglola Marlim/Brazil
Tordis/Na Uy Perdldo/vinh Mexico BC-10/Brazil Marimba/Brazil
Chu dau t u Total Petrobras
Statoil Shell Shell Petrobras
D o sau nUd 800 900
200 2.438 2.100 400
•API 1 7 - 2 2 19,6
19 22 1 6 - 2 4 2 0 - 3 0
Cong nghe SBP VASP + ESP
SBP SBP SBP VASP + ESP
Ket q u i First oil 2011 Tang san lupng tU35.000blpd len 44.000blpd Thu hoi tang 35MMbll, R F t a n g t U 4 9 % l e n 5 5 % L i p dat 2010 Lap dat 2009 N/A
DAU KM SO 3/2013 33
Oien ning can thiet de van hanh he thdng SBP la rat Idn. Trong mdt sd dU i n , do han che ve ngudn dien ning ed the cung cip cho miy bom (2,5MW) ma ngudi ta phii cii tien bom da pha tang ap ngam thudng thanh bam hybrid de dip Ung yeu cau.
Lua chpn he thdng SBP phu hpp (theo cdng suit, kich thude, khi ning xCf ly cit) de tdi Uu hieu qui dau tU.
Tii lieu tham khio
1 Offshore hydrocarbons. http://v\ww.
ifpenergiesnouvelles.com/publications/notes-de- synthese-panorama/panorama-2012
^. Pham Thanh Liem. Exploration and production activities in 2006-2010, plan for 2011 -2015 and strategy for future upstream activities. Deep water conference in Dalat -Vietnam. 12/9/2011.
3. Mads Hjelmeland. Framo engineering - subsea processing system. Deep water conference in Dalat - Vietnam. 12/9/2011.
4. Nikhil Chaube. FMC technologies - subsea separation.
Deep water Conference in Dalat - Vietnam. 12/9/2011.
j . Subsea boosting and processing developments.
http://www.offshore-mag.com/articles/print/volume-70/
issue-50/subsea/subsea-boosting-and.html 6. The subsea processing promise. http://www.
offshore-technology.com/features/feature1412.
'. VetcoGray integrated subsea systems. httpV/www.
ge-energy.com/content/multimedia/_files/downloads/
VetcoGray%20integrated%20subsea%20systems.pdf.
8. Framo subsea technologies. http://www.neesubsea.
no/publish_files/Framo_NCE_Presentation.pdf.
9. Subsea pumps. httpV/www.tekna.no/ikbViewer/
Content/22993/Nils%20Arne%20S%C3%B8lvik.pdf.
10. Comparison of multiphase pumping technologies for subsea and downhole applications. httpV/www.spe.
org/ogf/print/archives/2012/02/02_l 2_16_146784.pdf 11. Hybrid pump, a new type of pump for the Pazflor deep sea project, http://www.utc.no/content/
download/830/5042/version/5/file/1-i-Pierre.
12. Subsea separation and processing of oil, gas and produced water. httpy/wwn«.forum.rice.edu/wp-content/
uploads/2011/06/011312RT_Prescott.pdf.
13. John Preddy. Engineering of subsea productior\
systems. 20M.
14. Surface production operation. Volume I, 2"
edition. Ken Arnold and Maurice Steward - Gulf PublisM Company. 1999.
15. Terminal Velocity, http://en.wikipedia.org/wiki/
Terminal_velocity.
Subsea boosting and processing technology, a solution for enhancing oil recovery of offshore fields
Truong Due Trong, Hoang Thinh Nhan Petrovietnam University
Offshore exploration and production activities have been boomed since the 1950s and increasingly developed with the active participation of the world's leading oil and gas companies. According to statistics by 2010, offshore production regions represented nearly 650 billion barrels of oil equivalent (Gboe), accounting for 20% of known remaining global oil reserves 11]. Nevertheless, offshore production requires complex technologies as a result of water depth, fluid characteristics (viscosity, density, and impurities) and reservoir conditions (temperature, pressure, etc.) involved. This article introduces Subsea Boosting and Processing (SBP) technology, a new development which has been researched and tested with the aim of enhancing oil recovery of offshore fields, especially fields with high density oil and/or low pressure reservoir.
