Downhole Tshuaj Txhaum Kab-Vim Li Cas Lawv Ua Tsis Tau?Kev paub, kev sib tw thiab kev siv cov txheej txheem xeem tshiab
Copyright 2012, Society of Petroleum Engineers
Abstract
Statoil tab tom ua haujlwm ntau qhov chaw uas downhole nruam txhaj tshuaj ntawm nplai inhibitor siv.Lub hom phiaj yog los tiv thaiv lub raj sab sauv thiab kev nyab xeeb valve los ntawm (Ba/Sr) SO4orCaCO;scale, nyob rau hauv cov ntaub ntawv uas scale squeezing tej zaum yuav nyuaj thiab raug nqi mus ua ib tug tsis tu ncua, xws li khi-nyob rau hauv subsea teb.
Kev txhaj tshuaj tsis tu ncua ntawm nplai inhibitor downhole yog cov txheej txheem tsim nyog los tiv thaiv lub raj sab sauv thiab kev nyab xeeb valve hauv qhov dej uas muaj peev xwm ua kom siab tshaj qhov ntim khoom;tshwj xeeb tshaj yog nyob rau hauv lub qhov dej uas tsis tas yuav tsum tau nyem ib ntus vim muaj peev xwm scaling nyob ze ntawm qhov chaw zoo.
Kev tsim, kev khiav hauj lwm thiab kev tswj xyuas cov kab tshuaj txhaj tshuaj xav tau kev tsom mus rau kev xaiv cov khoom siv, tshuaj tsim nyog thiab kev saib xyuas.Lub siab, qhov kub thiab txias, ntws-kab lis kev cai thiab geometry ntawm lub kaw lus yuav qhia txog cov teeb meem rau kev ua haujlwm nyab xeeb.Cov kev sib tw tau raug txheeb xyuas nyob rau hauv ob peb mais 'ntev cov kab txhaj tshuaj los ntawm cov chaw tsim khoom mus rau cov qauv hauv qab dej hiav txwv thiab hauv cov tshuaj txhaj tshuaj hauv cov qhov dej.
Cov kev paub dhau los uas qhia txog qhov nyuaj ntawm downhole kev txhaj tshuaj tas li hais txog cov teeb meem nag lossis daus thiab corrosion.Laboratory kev tshawb fawb thiab kev siv cov txheej txheem tshiab rau kev tsim nyog tshuaj ib tug sawv cev.Cov kev xav tau rau ntau txoj kev qhuab qhia yog hais txog.
Taw qhia
Statoil tab tom ua haujlwm ntau qhov chaw uas cov tshuaj txhaj tshuaj tas li tau siv.Qhov no feem ntau yog txhaj tshuaj scale inhibitor (SI) qhov twg lub hom phiaj yog los tiv thaiv lub sab sauv tubing thiab downhole kev nyab xeeb valve (DHSV) los ntawm (Ba/Sr) SO4orCaCO;nplai.Qee zaum emulsion breaker yog txhaj downhole los pib txoj kev sib cais kom tob rau hauv lub qhov dej li qhov ua tau ntawm qhov kub thiab txias.
Kev txhaj tshuaj tsis tu ncua ntawm nplai inhibitor downhole yog cov txheej txheem tsim nyog los tiv thaiv sab sauv ntawm cov qhov dej uas muaj peev xwm ua kom siab tshaj qhov ntim khoom.Kev txhaj tshuaj tas mus li yuav raug pom zoo tshwj xeeb tshaj yog nyob rau hauv qhov dej uas tsis tas yuav tsum tau nyem vim tias muaj peev xwm ua kom tsawg nyob rau hauv qhov ze qhov dej;los yog nyob rau hauv cov ntaub ntawv uas scale squeezing tej zaum yuav nyuaj thiab raug nqi mus ua tsis tu ncua, xws li khi-nyob rau hauv subsea teb.
Statoil tau txuas ntxiv kev paub txog kev txhaj tshuaj txuas ntxiv mus rau cov txheej txheem sab saum toj thiab cov qauv hauv qab hiav txwv tab sis qhov kev sib tw tshiab yog coj mus rau qhov chaw txhaj tshuaj ntxiv rau hauv qhov dej.Kev tsim, kev khiav hauj lwm thiab kev tswj xyuas cov kab tshuaj txhaj tshuaj xav tau kev tsom mus rau ntau lub ntsiab lus;xws li kev xaiv cov khoom siv, tshuaj lom neeg tsim nyog thiab kev saib xyuas.Lub siab, qhov kub thiab txias, ntws-kab lis kev cai thiab geometry ntawm lub kaw lus yuav qhia txog cov teeb meem rau kev ua haujlwm nyab xeeb.Kev sib tw nyob rau hauv ntev (ntau mais) cov kab txhaj tshuaj los ntawm cov chaw tsim khoom mus rau cov qauv hauv qab dej hiav txwv thiab rau hauv cov dej txhaj tshuaj hauv cov qhov dej tau raug txheeb xyuas;Fig.1.Qee qhov kev txhaj tshuaj tau ua haujlwm raws li kev npaj, thaum lwm tus tau ua tsis tiav rau ntau yam.Ntau qhov kev tsim kho tshiab yog npaj rau kev txhaj tshuaj tshuaj downhole (DHCI);txawm li cas los xij;qee zaum cov cuab yeej siv tsis tau ua tiav tiav.
Kev siv DHCI yog ib txoj haujlwm nyuaj.Nws suav nrog kev ua tiav thiab kev tsim qauv zoo, zoo chemistry, topside system thiab cov tshuaj siv tshuaj ntawm cov txheej txheem saum toj kawg nkaus.Cov tshuaj yuav raug tso tawm los ntawm sab saum toj ntawm cov tshuaj txhaj tshuaj mus rau cov khoom tiav thiab nqis mus rau hauv qhov dej.Yog li ntawd, hauv kev npaj thiab ua tiav ntawm hom kev sib koom tes ntawm qhov project no yog qhov tseem ceeb heev.Ntau yam kev txiav txim siab yuav tsum tau soj ntsuam thiab kev sib txuas lus zoo thaum tsim qauv yog qhov tseem ceeb.Cov txheej txheem engineers, subsea engineers thiab ua tiav engineers tau koom nrog, cuam tshuam nrog cov ncauj lus ntawm kev ua kom zoo chemistry, xaiv cov khoom siv, kev ruaj ntseg txaus thiab kev tswj cov tshuaj lom neeg.Cov teeb meem tuaj yeem yog huab tais phom tshuaj los yog qhov kub thiab txias, corrosion thiab qee zaum muaj lub tshuab nqus tsev vim lub zog hauv zos thiab ntws los ntawm cov tshuaj txhaj tshuaj.Ntxiv rau qhov no, tej yam kev mob xws li kev kub siab, kub siab, siab roj nqi, siab scaling peev xwm,qhov ntev ntawm qhov chaw txhaj tshuaj thiab qhov tob tob hauv qhov dej, muab cov kev sib tw sib txawv thiab cov kev xav tau rau cov tshuaj txhaj tshuaj thiab txhaj tshuaj valve.
Kev saib xyuas ntawm DHCI systems tau teeb tsa hauv Statoil kev ua haujlwm qhia tau hais tias qhov kev paub dhau los tsis yog ib txwm ua tiav Table 1. Txawm li cas los xij, kev npaj rau kev txhim kho cov qauv tsim, tshuaj tsim nyog, kev ua haujlwm thiab kev saib xyuas yog ua tiav.Cov kev sib tw sib txawv ntawm qhov chaw mus rau qhov chaw, thiab qhov teeb meem tsis tas yuav tsum yog tias cov tshuaj txhaj tshuaj valve nws tus kheej tsis ua haujlwm.
Nyob rau xyoo tas los no muaj ntau qhov kev sib tw txog cov tshuaj txhaj tshuaj downhole tau ntsib.Hauv daim ntawv no, qee qhov piv txwv tau muab los ntawm cov kev paub dhau los no.Daim ntawv tham txog cov teeb meem thiab kev ntsuas los daws cov teeb meem ntsig txog DHCI kab.Ob qhov xwm txheej keeb kwm tau muab;ib qho ntawm corrosion thiab ib qho ntawm cov tshuaj phom huab tais.Cov kev paub dhau los uas qhia txog qhov nyuaj ntawm downhole kev txhaj tshuaj tas li hais txog cov teeb meem nag lossis daus thiab corrosion.
Cov kev tshawb fawb hauv chav kuaj thiab siv cov txheej txheem tshiab rau kev tsim nyog tshuaj lom neeg kuj raug txiav txim siab;yuav ua li cas rau cov tshuaj, scaling muaj peev xwm thiab kev tiv thaiv, complex cov cuab yeej siv thiab yuav ua li cas cov tshuaj yuav cuam tshuam rau lub topside system thaum cov tshuaj yog tsim rov qab.Txais cov txheej txheem rau kev siv tshuaj lom neeg muaj feem cuam tshuam txog ib puag ncig, kev ua haujlwm zoo, lub peev xwm cia sab saum toj, lub twj tso kua mis, seb lub twj tso kua mis uas twb muaj lawm tuaj yeem siv thiab lwm yam. Cov lus pom zoo yuav tsum ua raws li cov kua dej thiab chemistry compatibility, residual nrhiav tau, cov khoom siv sib xws, subsea umbilical design, chemical dosage system. thiab cov ntaub ntawv nyob ib puag ncig ntawm cov kab no.Cov tshuaj yuav tsum tau hydrate inhibited los tiv thaiv plugging ntawm cov kab txhaj tshuaj los ntawm cov pa ntxeem tau thiab cov tshuaj yuav tsum tsis txhob khov thaum thauj thiab cia.Nyob rau hauv cov txheej txheem sab hauv uas twb muaj lawm muaj ib daim ntawv teev cov tshuaj uas yuav siv tau nyob rau hauv txhua lub ntsiab lus nyob rau hauv lub cev lub cev xws li viscosity yog ib qho tseem ceeb.Qhov kev txhaj tshuaj tuaj yeem hais txog 3-50km kev ncua deb ntawm txoj hlab ntaws subsea ntws thiab 1-3km rau hauv qhov dej.Yog li ntawd, qhov kub thiab txias stability kuj tseem ceeb heev.Kev ntsuam xyuas ntawm cov teebmeem hauv qab, piv txwv li hauv cov chaw ua kom zoo nkauj kuj yuav tsum tau txiav txim siab.
Downhole tshuaj txhaj tshuab
Tus nqi pab
Kev txhaj tshuaj tsis tu ncua ntawm nplai inhibitor downhole los tiv thaiv DHS Vor cov tubing ntau lawm tej zaum yuav raug nqi zoo piv rau kev nyem qhov dej nrog nplai inhibitor.Daim ntawv thov no txo qhov muaj peev xwm tsim kev puas tsuaj piv rau kev kho cov nplai nyem, txo qhov muaj peev xwm rau cov txheej txheem teeb meem tom qab lub nplai nyem thiab muab qhov muaj peev xwm los tswj cov tshuaj txhaj tshuaj los ntawm kev txhaj tshuaj sab saum toj.Lub tshuab txhaj tshuaj kuj tseem siv tau los txhaj lwm cov tshuaj tsis tu ncua downhole thiab tuaj yeem txo qis lwm yam kev sib tw uas yuav tshwm sim ntxiv rau hauv cov txheej txheem cog.
Ib txoj kev tshawb fawb dav dav tau ua tiav los txhim kho qhov ntsuas qhov ntsuas ntawm Oseberg S lossis thaj chaw.Qhov kev txhawj xeeb loj yog CaCO;scaling nyob rau hauv lub Upper tubing thiab ua tau DHSV tsis ua hauj lwm.Lub Oseberg S los yog scale tswj lub tswv yim txiav txim siab hais tias nyob rau hauv peb lub xyoos lub sij hawm, DHCI yog tus nqi ntau npaum li cas daws nyob rau hauv lub qhov dej uas cov tshuaj txhaj tshuaj ua hauj lwm.Tus nqi tseem ceeb hais txog cov txheej txheem sib tw ntawm cov nplai nyem yog cov roj ncua sij hawm ntau dua li cov nqi tshuaj / kev ua haujlwm.Rau kev siv cov nplai inhibitor hauv kev nqa roj, qhov tseem ceeb ntawm cov nqi tshuaj yog cov roj nqa siab uas ua rau siab SI concentration, vim tias qhov concentration yuav tsum sib npaug nrog cov roj nqa tus nqi kom tsis txhob muaj tshuaj lom neeg huab tais.Rau ob lub qhov dej ntawm Oseberg S lossis uas tau ua haujlwm zoo DHC I kab, qhov kev xaiv no raug xaiv los tiv thaiv DHS V's tiv thaiv CaCO;kev ntsuas.
Nruam kev txhaj tshuaj system thiab li qub
Cov kev daws teeb meem uas twb muaj lawm siv cov tshuaj txhaj tshuaj tas mus li ntsib cov teeb meem los tiv thaiv kev ntsaws ntawm cov kab capillary.Feem ntau cov txheej txheem txhaj tshuaj muaj cov kab capillary, 1/4 "los yog 3/8" sab nraud txoj kab uas hla (OD), txuas mus rau ib qho chaw manifold, pub los ntawm-thiab txuas nrog lub tubing hanger ntawm sab annular ntawm lub raj.Cov kab capillary txuas mus rau sab nraud ntawm cov tubing ntau lawm los ntawm tshwj xeeb tubing dab tshos clamps thiab khiav ntawm sab nraud ntawm cov tubing mus rau hauv cov tshuaj txhaj tshuaj mandrel.Lub mandrel yog ib txwm muab tso rau hauv cov dej ntws ntawm DHS V los yog ntxaum hauv lub qhov dej nrog lub hom phiaj ntawm kev muab cov tshuaj txhaj tshuaj txaus rau lub sijhawm dispersion thiab tso cov tshuaj nyob qhov twg cov teeb meem pom.
Ntawm cov tshuaj txhaj tshuaj valve, Fig.2, ib daim cartridge me me txog 1.5 "nyob rau hauv txoj kab uas hla muaj cov check li qub uas tiv thaiv cov dej tsis zoo los ntawm cov kab capillary.Nws tsuas yog me me poppet caij caij nplooj ntoos hlav.Lub caij nplooj ntoos hlav quab yuam teeb thiab kwv yees lub siab xav tau los qhib lub poppet tawm ntawm lub rooj sib khi.Thaum cov tshuaj pib ntws, lub poppet raug tshem tawm ntawm nws lub rooj thiab qhib lub valve.
Nws yuav tsum muaj ob daim tshev valve ntsia.Ib lub valve yog lub hauv paus thaiv kev tiv thaiv cov kua dej hauv qhov dej nkag mus rau hauv kab capillary.Qhov no muaj qhov qhib siab tsis tshua muaj siab (2-15bars) .Yog tias lub siab hydrostatic nyob rau hauv kab capillary tsawg dua li qhov siab ntawm qhov dej, cov kua dej hauv lub qhov dej yuav sim nkag mus rau hauv cov kab capillary.Lwm daim tshev valve muaj atypical qhib siab ntawm 130-250 tuav thiab hu ua U-tube tiv thaiv kab ke.Lub valve no tiv thaiv cov tshuaj nyob rau hauv cov kab capillary kom dawb do ntws mus rau hauv lub qhov dej yog tias lub siab hydrostatic nyob rau hauv cov kab capillary yuav siab tshaj qhov siab ntawm lub qhov dej ntawm qhov chaw txhaj tshuaj hauv cov tubing.
Ntxiv nrog rau ob lub tshev li qub, feem ntau muaj cov lim dej hauv kab, lub hom phiaj ntawm qhov no yog los xyuas kom meej tias tsis muaj cov khib nyiab ntawm txhua yam tuaj yeem ua rau muaj kev cuam tshuam lub peev xwm ntawm lub kaw lus valve.
Qhov ntau thiab tsawg ntawm cov kos li qub tau piav qhia yog qhov me me, thiab kev huv ntawm cov tshuaj txhaj tshuaj yog qhov tseem ceeb rau lawv txoj haujlwm ua haujlwm.Nws ntseeg tau tias cov khib nyiab hauv qhov system tuaj yeem raug tshem tawm los ntawm kev ua kom cov dej ntws hauv cov kab capillary, kom cov tshev valve yuav qhib.
Thaum lub pob valve qhib, cov dej ntws nrawm nrawm nrawm thiab nthuav tawm cov kab capillary kom txog thaum lub siab rov nce ntxiv.Lub tshev valve yuav kaw kom txog thaum cov dej ntws ntawm cov tshuaj tsim kom muaj lub siab txaus los qhib lub valve;Qhov tshwm sim yog siab oscillations nyob rau hauv lub check valve system.Lub siab qhib siab dua lub kaw lus valve muaj, qhov tsawg txaus cheeb tsam yog tsim thaum lub kos valve qhib thiab lub kaw lus sim ua kom muaj kev sib npaug.
Cov tshuaj txhaj tshuaj li qub muaj qhov qhib siab;thiab yuav tsum lub raj siab ntawm cov tshuaj inlet point ua tsawg tshaj li qhov sib npaug ntawm hydrostatic siab ntawm cov tshuaj nyob rau hauv cov kab capillary ntxiv rau cov kos valve qhib siab, nyob ze lub tshuab nqus tsev los yog lub tshuab nqus tsev yuav tshwm sim nyob rau sab sauv ntawm cov kab capillary.Thaum qhov kev txhaj tshuaj ntawm cov tshuaj nres lossis cov dej ntws ntawm cov tshuaj tsis tshua muaj, nyob ze ntawm lub tshuab nqus tsev yuav pib tshwm sim nyob rau sab saum toj ntawm cov kab capillary.
Cov theem ntawm lub tshuab nqus tsev yog nyob ntawm qhov siab ntawm lub qhov dej, qhov tshwj xeeb ntawm cov tshuaj txhaj tshuaj sib xyaw siv hauv cov kab capillary, daim tshev valve qhib siab ntawm qhov chaw txhaj tshuaj thiab qhov ntws ntawm cov tshuaj hauv cov kab capillary.Cov xwm txheej hauv qhov dej yuav txawv ntawm lub sijhawm ua haujlwm thiab lub peev xwm ntawm lub tshuab nqus tsev yuav sib txawv raws sijhawm.Nws yog ib qho tseem ceeb kom paub txog qhov xwm txheej no kom ua tib zoo xav thiab ceev faj ua ntej yuav muaj teeb meem tshwm sim.
Ua ke nrog cov nqi txhaj tshuaj tsawg, feem ntau cov kuab tshuaj siv rau hauv cov ntawv thov no yog evaporating ua rau cov teebmeem uas tsis tau tshawb pom tag nrho.Cov teebmeem no yog phom huab tais lossis nag lossis daus ntawm cov khib nyiab, piv txwv li polymers, thaum cov kuab tshuaj evaporating.
Tsis tas li ntawd, galvanic hlwb tuaj yeem tsim nyob rau hauv lub sijhawm hloov pauv ntawm cov kua dej ntawm cov tshuaj thiab cov vapor ntim ze-nqus roj theem saum toj no.Qhov no tuaj yeem ua rau lub zos pitting corrosion nyob rau hauv cov kab capillary raws li qhov tshwm sim ntawm kev ua phem ntawm cov tshuaj nyob rau hauv cov xwm txheej no.Flakes los yog ntsev crystals tsim raws li ib tug zaj duab xis nyob rau hauv lub capillary kab raws li nws sab hauv dries tawm yuav jam los yog ntsaws cov kab capillary.
Zoo barrier philosophy
Thaum tsim cov kev daws teeb meem zoo, Statoil xav kom muaj kev nyab xeeb hauv qhov dej txhua lub sijhawm thaum lub sijhawm ua haujlwm ntawm lub qhov dej.Yog li, Statoil xav kom muaj ob lub qhov dej tsis muaj kev ywj pheej zoo li qub.Daim duab 3 qhia tau hais tias atypical zoo barrier schematic, qhov twg cov xim xiav sawv cev rau lub hnab ntawv tseem ceeb barrier;nyob rau hauv cov ntaub ntawv no ntau lawm tubing.Cov xim liab sawv cev rau lub hnab ntawv thib ob;lub casing.Nyob rau sab laug sab hauv daim duab kos duab cov tshuaj txhaj tshuaj yog qhia raws li ib tug blackline nrog txhaj tshuaj taw tes rau cov tubing ntau lawm nyob rau hauv lub cheeb tsam cim liab (secondary barrier).Los ntawm kev qhia txog cov tshuaj txhaj tshuaj rau hauv lub qhov dej, ob qho tib si thawj thiab theem nrab cov kab mob hauv qhov dej tau raug puas tsuaj.
Case keeb kwm ntawm corrosion
Ib ntus ntawm cov xwm txheej
Downhole tshuaj txhaj tshuaj ntawm nplai inhibitor tau siv rau hauv qhov chaw roj ua haujlwm los ntawm Statoil ntawm Norwegian Continental Shelf.Nyob rau hauv cov ntaub ntawv no, scale inhibitor thov tau Ameslikas tsim nyog rau topside thiab subsea daim ntawv thov.Kev ua tiav ntawm qhov dej tau ua raws li kev teeb tsa ntawm DHCIpointat2446mMD, Fig.3.Kev txhaj tshuaj downhole ntawm topside scale inhibitor tau pib yam tsis muaj kev sim tshuaj ntxiv.
Tom qab ib xyoos ntawm kev ua haujlwm xau hauv cov tshuaj txhaj tshuaj tau pom thiab kev tshawb nrhiav tau pib.Cov dej xau tau ua rau muaj kev puas tsuaj rau lub qhov dej thaiv.Cov xwm txheej zoo sib xws tau tshwm sim rau ob peb lub qhov dej thiab qee qhov ntawm lawv yuav tsum raug kaw thaum qhov kev tshawb nrhiav txuas ntxiv mus.
Cov tubing ntau lawm tau rub thiab kawm kom ntxaws.Qhov kev tawm tsam corrosion tau txwv rau ib sab ntawm cov tubing, thiab qee cov tubing cov pob qij txha tau corroded uas muaj qhov tiag los ntawm lawv.Kwv yees li 8.5 hli tuab 3% chrome hlau tau tawg hauv tsawg dua 8 lub hlis.Lub ntsiab corrosion tau tshwm sim nyob rau sab saum toj ntawm lub qhov dej, los ntawm lub taub hau mus rau kwv yees li 380m MD, thiab qhov phem tshaj plaws corroded tubing pob qij txha tau pom nyob ib ncig ntawm kwv yees li 350m MD.Hauv qab no qhov tob me me lossis tsis muaj corrosion tau pom, tab sis ntau cov khib nyiab tau pom ntawm lub raj OD's.
Lub 9-5/8 '' casing kuj raug txiav thiab rub thiab cov teebmeem zoo sib xws tau pom;nrog corrosion nyob rau sab sauv ntawm lub qhov dej ntawm ib sab nkaus xwb.Lub induced leak yog tshwm sim los ntawm bursting qhov tsis muaj zog seem ntawm lub casing.
Cov khoom siv tshuaj txhaj tshuaj yog Alloy 825.
Kev tsim nyog tshuaj
Cov khoom siv tshuaj lom neeg thiab kev kuaj corrosion yog qhov tseem ceeb hauv kev tsim nyog ntawm cov nplai inhibitors thiab qhov tseeb nplai inhibitor tau tsim nyog thiab siv rau hauv cov ntawv thov sab saum toj thiab hauv qab dej tau ntau xyoo.Yog vim li cas rau kev siv cov tshuaj downhole tiag tiag tau txhim kho ib puag ncig cov khoom los ntawm kev hloov cov tshuaj downhole uas twb muaj lawm Txawm li cas los xij, cov nplai inhibitor tsuas yog siv nyob rau sab saum toj thiab hiav txwv kub (4-20 ℃).Thaum txhaj rau hauv lub qhov dej qhov kub ntawm cov tshuaj yuav siab li 90 ℃, tab sis tsis muaj kev sim ntxiv ntawm qhov ntsuas kub no.
Kev ntsuam xyuas corrosivity pib tau ua los ntawm cov khoom siv tshuaj thiab cov txiaj ntsig tau pom 2-4 hli / xyoo rau carbon steel ntawm qhov kub thiab txias.Thaum lub sij hawm no tau muaj qhov tsawg kawg nkaus kev koom tes ntawm cov ntaub ntawv technical competence ntawm tus neeg teb xov tooj.Cov kev ntsuam xyuas tshiab tom qab tau ua los ntawm tus neeg teb xov tooj qhia tias qhov ntsuas qhov ntsuas tau ua rau cov khoom siv hauv cov tubing ntau lawm thiab cov casing, nrog cov nqi corrosion ntau tshaj 70mm / xyoo.Cov khoom siv tshuaj txhaj tshuaj Alloy 825 tsis tau sim tawm tsam cov nplai inhibitor ua ntej txhaj tshuaj.Qhov kub ntawm qhov dej tuaj yeem ncav cuag 90 ℃ thiab cov kev ntsuas txaus yuav tsum tau ua raws li cov xwm txheej no.
Kev tshawb nrhiav kuj tau qhia tias cov nplai inhibitor raws li cov tshuaj muaj zog tau tshaj tawm pH ntawm <3.0.Txawm li cas los xij, pH tsis tau ntsuas.Tom qab ntawd qhov ntsuas pH pom tus nqi qis heev ntawm pH 0-1.Qhov no qhia txog qhov xav tau rau kev ntsuas thiab kev txiav txim siab ntawm cov khoom siv ntxiv rau cov nqi pH.
Kev txhais cov ntsiab lus
Cov kab txhaj tshuaj (Fig.3) yog tsim los muab hydrostatic siab ntawm cov nplai inhibitor uas tshaj siab nyob rau hauv zoo ntawm qhov chaw txhaj tshuaj.Tus inhibitor yog txhaj ntawm lub siab siab dua li muaj nyob rau hauv lub qhov dej.Qhov no ua rau muaj kev cuam tshuam U-tube ntawm lub qhov dej kaw.Lub valve yuav ib txwm qhib nrog lub siab siab dua hauv cov kab txhaj tshuaj ntau dua li hauv qhov dej.Lub tshuab nqus tsev los yog evaporation nyob rau hauv cov kab txhaj tshuaj yuav tshwm sim.Tus nqi corrosion thiab kev pheej hmoo ntawm pitting yog loj tshaj nyob rau hauv cov pa roj/kua hloov chaw vim evaporation ntawm cov kuab tshuaj.Laboratory thwmsim ua nyob rau hauv daim coupon no tau lees paub qhov kev xav no.Nyob rau hauv lub qhov dej uas muaj kev to, tag nrho cov qhov nyob rau hauv cov kab txhaj tshuaj nyob rau hauv lub Upper ib feem ntawm cov tshuaj txhaj kab.
Daim duab 4 qhia txog kev yees duab ntawm DHC I kab nrog qhov tseem ceeb pitting corrosion.Lub corrosion pom nyob rau sab nrauv cov tubing qhia tau hais tias ib cheeb tsam raug tus nplai inhibitor los ntawm pitting to point.Cov to yog tshwm sim los ntawm pitting corrosion los ntawm cov tshuaj corrosive heev thiab to los ntawm cov tshuaj txhaj tshuaj mus rau hauv lub casing ntau lawm.Tus nplai inhibitor tau txau los ntawm cov kab pitted capillary mus rau casing thiab tubing thiab xau tshwm sim.Ib qho kev tshwm sim thib ob ntawm kev xau hauv kab txhaj tshuaj tsis tau txiav txim siab.Nws tau txiav txim siab tias qhov casing-thiab tubing corrosion yog tshwm sim los ntawm concentrated scale inhibitors thov ntawm pitted capillary kab mus rau lub casing thiab tubing, Fig.5.
Nyob rau hauv rooj plaub no tau muaj tsis muaj kev koom tes ntawm cov khoom muaj peev xwm engineers.Corrosivity ntawm cov tshuaj ntawm cov kab DHCI tsis tau raug kuaj thiab cov teebmeem thib ob vim kev xau tsis tau raug soj ntsuam;xws li seb cov ntaub ntawv nyob ib puag ncig tuaj yeem tiv taus cov tshuaj lom neeg.
Cov ntaub ntawv keeb kwm ntawm huab tais tshuaj lom neeg phom
Ib ntus ntawm cov xwm txheej
Lub tswv yim tiv thaiv nplai rau HP HT teb yog kev txhaj tshuaj tas li ntawm cov nplai inhibitor upstream downhole kev nyab xeeb valve.Ib qho loj calcium carbonate scaling peev xwm tau txheeb xyuas nyob rau hauv lub qhov dej.Ib qho ntawm cov kev sib tw yog qhov kub thiab txias thiab cov pa roj thiab cov condensate ntau lawm ua ke nrog cov dej tsis tshua muaj nqi.Qhov kev txhawj xeeb los ntawm kev txhaj tshuaj scale inhibitor yog tias cov kuab tshuaj yuav raug muab tshem tawm los ntawm cov roj ntau lawm thiab cov phom huab tais ntawm cov tshuaj yuav tshwm sim ntawm qhov chaw txhaj tshuaj ntawm qhov kev nyab xeeb valve hauv qhov dej, Fig.1.
Thaum lub sij hawm tsim nyog ntawm scale inhibitor lub tsom xam yog nyob rau hauv lub efficiency ntawm cov khoom ntawm HP HT tej yam kev mob nrog rau tus cwj pwm nyob rau hauv lub topside txheej txheem system (tsawg kub).nag lossis daus ntawm cov nplai inhibitor nws tus kheej nyob rau hauv cov tubing ntau lawm vim lub siab roj tus nqi yog lub ntsiab kev txhawj xeeb.Cov kev sim kuaj pom tau tias cov nplai inhibitor tuaj yeem ua rau nag thiab ua raws li cov phab ntsa ntawm cov tubing.Kev ua haujlwm ntawm qhov kev nyab xeeb valve tuaj yeem ua rau muaj kev pheej hmoo.
Kev paub tau pom tias tom qab ob peb lub lis piam ntawm kev ua haujlwm, cov tshuaj lom neeg tau xau.Nws muaj peev xwm saib xyuas lub siab zoo ntawm qhov ntsuas qhov chaw nruab rau hauv kab capillary.Txoj kab raug cais kom tau txais kev ncaj ncees zoo.
Cov kab tshuaj txhaj tshuaj tau rub tawm ntawm lub qhov dej, qhib thiab tshuaj xyuas kom kuaj pom qhov teeb meem thiab nrhiav tau qhov laj thawj ntawm kev ua tsis tiav.Raws li tuaj yeem pom hauv Fig.6, qhov tseem ceeb ntawm cov nag lossis daus tau pom thiab tshuaj ntsuam xyuas tau pom tias qee qhov ntawm qhov no yog tus nplai inhibitor.Lub precipitate nyob ntawm lub foob thiab lub poppet thiab lub valve tsis tuaj yeem ua haujlwm.
Lub valve tsis ua hauj lwm yog tshwm sim los ntawm cov khib nyiab hauv lub valve tiv thaiv cov tshev valve noj ntawm cov hlau mus rau lub rooj zaum hlau.Cov khib nyiab tau raug tshuaj xyuas thiab cov ntsiab lus tseem ceeb tau ua pov thawj tias yog hlau shavings, tej zaum tsim thaum lub sij hawm installation txheej txheem ntawm cov kab capillary.Tsis tas li ntawd, qee cov khib nyiab dawb tau txheeb xyuas ntawm ob lub tshev valve tshwj xeeb tshaj yog nyob rau sab nraub qaum ntawm lub li qub.Qhov no yog qhov tsis tshua muaj siab sab, piv txwv li sab ib txwm nyob rau hauv kev sib cuag nrog cov kua dej hauv qhov dej.Thaum xub thawj, qhov no tau ntseeg tias yog cov khib nyiab los ntawm qhov chaw tsim khoom vim tias cov li qub tau raug kaw qhib thiab raug rau cov kua dej hauv qhov dej.Tab sis kev tshuaj xyuas cov khib nyiab pov thawj tias yog polymers nrog cov tshuaj zoo sib xws li cov tshuaj siv los ua cov nplai inhibitor.Qhov no ntes tau peb cov kev txaus siab thiab Statoil xav tshawb nrhiav cov laj thawj tom qab cov khib nyiab polymer tam sim no hauv kab capillary.
Kev tsim nyog tshuaj
Hauv HP HT teb muaj ntau yam kev sib tw nrog rau kev xaiv cov tshuaj tsim nyog los txo cov teeb meem ntau lawm.Nyob rau hauv kev tsim nyog ntawm scale inhibitor rau kev txhaj tshuaj tas li downhole, cov kev sim hauv qab no tau ua:
● Khoom ruaj khov
● Thermal aging
● Dynamic Performance tests
● Compatibility nrog tsim dej thiab hydrate inhibitor (MEG)
● Zoo li qub thiab dynamic phom huab tais xeem
● Re-dissolution ntaub ntawv dej, tshiab tshuaj thiab MEG
Cov tshuaj yuav raug txhaj rau ntawm tus nqi predetermined npaum li cas,tab sis kev tsim cov dej yuav tsis tas yuav tas mus li,ie slugging dej.Hauv nruab nrab ntawm cov dej slugs,thaum cov tshuaj nkag mus rau hauv lub qhov dej,nws yuav ntsib los ntawm kub,ceev ntws ntws ntawm hydrocarbon gas.Qhov no zoo ib yam li kev txhaj tshuaj scale inhibitor hauv daim ntawv thov nqa roj (Fleming etal.2003) .Ua ke nrog
cov roj kub kub,Qhov kev pheej hmoo ntawm cov kuab tshuaj stripping yog qhov siab heev thiab tus huab tais rab phom tuaj yeem ua rau txhaws ntawm qhov txhaj tshuaj valve.Qhov no yog ib qho kev pheej hmoo txawm tias cov tshuaj formulated nrog kub kub taw tes / qis vapor siab cov kuab tshuaj thiab lwm yam Vapor Pressure Depressants (VPD's).,flow ntawm tsim dej,MEG thiab / lossis cov tshuaj tshiab yuav tsum muaj peev xwm tshem tawm lossis rov ua kom lub cev qhuav dej los yog phom tawm cov tshuaj.
Nyob rau hauv cov ntaub ntawv no ib tug tshiab kuaj kuaj rig yog tsim los replicate ntws tej yam kev mob nyob ze ntawm lub txhaj tshuaj ports ntawm ib tug HP / HTg raws li ntau lawm system.Cov txiaj ntsig tau los ntawm kev sim phom dynamic huab tais qhia tau hais tias nyob rau hauv daim ntawv thov kev thov ib qho tseem ceeb hnyav poob tau raug kaw.Qhov no tuaj yeem ua rau tus huab tais rab phom ceev thiab qhov kawg ntawm kev thaiv cov flowlines.Kev ua haujlwm yog li ntawd pom tau tias muaj kev pheej hmoo tseem ceeb rau kev txhaj tshuaj tsis tu ncua hauv cov qhov dej no ua ntej kev tsim dej thiab ua rau kev txiav txim siab los kho cov txheej txheem pib ua haujlwm rau daim teb no, ncua tshuaj txhaj tshuaj kom txog thaum kuaj pom cov dej tawg.
Qhov tsim nyog ntawm nplai inhibitor rau kev txhaj tshuaj tas mus li downhole tau ua kom pom tseeb ntawm cov kuab tshuaj stripping thiab rab phom huab tais ntawm cov nplai inhibitor ntawm qhov chaw txhaj tshuaj thiab hauv cov flowline tab sis lub peev xwm rau rab phom huab tais hauv qhov txhaj tshuaj nws tus kheej tsis raug tshuaj xyuas.Qhov kev txhaj tshuaj valve tej zaum yuav ua tsis tiav vim qhov hnyav hnyav poob thiab huab tais phom ceev,Fig.6.Qhov kev tshwm sim qhia tau hais tias nws yog ib qho tseem ceeb uas yuav tsum muaj kev pom zoo ntawm qhov system;tsis tsuas yog tsom rau cov kev sib tw ntau lawm,tab sis kuj muaj teeb meem cuam tshuam txog kev txhaj tshuaj ntawm cov tshuaj,ie txhaj valve.
Kev paub los ntawm lwm qhov chaw
Ib qho ntawm cov ntawv tshaj tawm thaum ntxov ntawm cov teeb meem nrog cov tshuaj txhaj tshuaj ntev ntev yog los ntawm Gull fak sandVig dis satellite fields (Osa etal.2001) .Lub subsea txhaj kab raug thaiv los ntawm hydrate tsim nyob rau hauv txoj kab vim muaj kev cuam tshuam ntawm cov pa roj los ntawm cov kua dej ua kua. nyob rau hauv txoj kab ntawm kev txhaj tshuaj valve.Cov txheej txheem tshiab rau kev tsim cov tshuaj subsea ntau lawm tau tsim.Cov kev cai muaj xws li kev tshem tawm particle (filtration) thiab ntxiv cov hydrate inhibitor (xws li glycol) rau tag nrho cov dej raws li nplai inhibitors yuav tsum tau txhaj ntawm cov qauv hauv qab hiav txwv.Tshuaj stability,viscosity thiab compatibility (kua thiab cov ntaub ntawv) kuj raug txiav txim.Cov kev cai no tau coj mus ntxiv rau hauv Statoil system thiab suav nrog cov tshuaj txhaj tshuaj downhole.
Thaum lub sij hawm txoj kev loj hlob ntawm Oseberg S los yog teb nws tau txiav txim siab tias tag nrho cov qhov dej yuav tsum ua kom tiav nrog DHC I systems (Fleming etal.2006).Lub hom phiaj yog los tiv thaiv CaCO..scaling nyob rau hauv lub Upper tubing los ntawm SI txhaj.Ib qho ntawm cov teeb meem loj nrog rau cov kab tshuaj txhaj tshuaj yog ua tiav kev sib txuas lus ntawm qhov chaw thiab qhov hluav taws xob downhole.Txoj kab uas hla ntawm cov tshuaj txhaj tshuaj tau nqaim los ntawm 7mm mus rau 0.7mm (ID) nyob ib ncig ntawm lub annulus kev nyab xeeb valve vim qhov chaw txwv thiab lub peev xwm ntawm cov kua thauj mus los ntawm ntu no tau cuam tshuam rau txoj kev vam meej.Ntau lub qhov dej hauv lub platform muaj cov tshuaj txhaj tshuaj uas tau ntsaws,tab sis vim li cas ho tsis to taub.Tsheb ciav hlau ntawm ntau yam kua (glycol,nyoos,condensate,xylene ua,scale inhibitor,dej thiab lwm yam) tau kuaj sim rau viscosity thiab compatibility thiab pumped rau pem hauv ntej thiab rov qab ntws los qhib cov kab;txawm li cas los xij,lub hom phiaj scale inhibitor tsis tuaj yeem rub tawm mus rau hauv cov tshuaj txhaj tshuaj valve.Ntxiv mus,Cov teeb meem tau pom nrog nag lossis daus ntawm phosphonate scale inhibitor ua ke nrog cov seem CaCl z tiav brine hauv ib lub qhov dej thiab rab phom huab tais ntawm cov nplai inhibitor hauv lub qhov dej nrog cov roj av siab thiab cov dej qis (Fleming etal.2006)
Cov kev kawm tau kawm
Kev sim txoj kev txhim kho
Cov ntsiab lus tseem ceeb tau kawm los ntawm qhov tsis ua haujlwm ntawm DHC I systems tau hais txog kev ua haujlwm ntawm cov nplai inhibitor thiab tsis yog hais txog kev ua haujlwm thiab tshuaj txhaj tshuaj.Kev txhaj tshuaj sab saum toj thiab kev txhaj tshuaj subsea tau ua haujlwm zoo tshaj sijhawm;txawm li cas los xij,daim ntawv thov tau txuas ntxiv mus rau downhole tshuaj txhaj tshuaj yam tsis muaj kev hloov kho tshiab ntawm cov txheej txheem tshuaj tsim nyog.Statoil qhov kev paub dhau los ntawm ob qhov xwm txheej tau nthuav tawm yog tias cov ntaub ntawv tswj hwm lossis cov txheej txheem rau kev tsim nyog tshuaj yuav tsum tau hloov kho kom suav nrog hom kev thov tshuaj no.Ob qhov kev sib tw tseem ceeb tau raug txheeb xyuas raws li i) lub tshuab nqus tsev hauv cov tshuaj txhaj tshuaj thiab ii) muaj peev xwm los nag lossis daus ntawm cov tshuaj.
evaporation ntawm cov tshuaj yuav tshwm sim nyob rau hauv lub tubing ntau lawm (raws li pom nyob rau hauv lub phom huab tais rooj plaub) thiab nyob rau hauv lub txhaj tshuaj (ib ntus interface tau raug txheeb xyuas nyob rau hauv lub tshuab nqus tsev case) muaj kev pheej hmoo tias cov precipitates tej zaum yuav tsiv mus nyob rau hauv lub ntws thiab nyob rau hauv lub txhaj tshuaj valve thiab txuas ntxiv mus rau hauv lub qhov dej.Kev txhaj tshuaj valve feem ntau yog tsim los nrog lub lim dej ntawm qhov chaw txhaj tshuaj,qhov no yog kev sib tw,raws li nyob rau hauv cov ntaub ntawv ntawm nag lossis daus no lim yuav raug ntsaws ua rau lub valve tsis ua hauj lwm.
Cov kev soj ntsuam thiab cov lus xaus ua ntej los ntawm cov tshooj lus kawm tau ua rau muaj kev tshawb fawb hauv chav kuaj dav dav ntawm qhov tshwm sim.Lub hom phiaj tag nrho yog los tsim cov kev tsim nyog tshiab kom tsis txhob muaj teeb meem zoo sib xws rau yav tom ntej.Nyob rau hauv txoj kev tshawb no ntau yam kev ntsuam xyuas tau ua-ua thiab ntau txoj hauv kev kuaj tau raug tsim (tsim nyob rau hauv kev txiav txim) los tshuaj xyuas cov tshuaj uas hais txog cov teeb meem uas raug txheeb xyuas.
● Lim blockages thiab khoom ruaj khov nyob rau hauv kaw tshuab.
● Cov nyhuv ntawm ib feem ntawm cov kuab tshuaj poob rau ntawm corrosivity ntawm cov tshuaj.
● Cov nyhuv ntawm ib feem ntawm cov kuab tshuaj poob nyob rau hauv ib tug capillary ntawm tsim ntawm cov khib nyiab los yog viscous plugs.
Thaum lub sij hawm cov kev ntsuam xyuas ntawm cov kev kuaj sim muaj ob peb yam teeb meem tau raug txheeb xyuas
● Rov ua dua lim thaiv thiab tsis muaj kev ruaj ntseg.
● Cov khoom tsim tom qab ib nrab evaporation los ntawm capillary
● PH hloov vim qhov hnyav poob.
Qhov xwm txheej ntawm qhov kev sim ua tau kuj tau muab cov ntaub ntawv ntxiv thiab kev paub txog kev hloov pauv hauv lub cev ntawm cov tshuaj hauv capillaries thaum raug rau qee yam mob.,thiab qhov no txawv ntawm cov kev daws teeb meem ntau npaum li cas raug rau cov xwm txheej zoo sib xws.Kev sim ua haujlwm kuj tau txheeb xyuas qhov sib txawv ntawm cov kua dej ntau,vapor theem thiab cov kua dej seem uas tuaj yeem ua rau muaj peev xwm ua rau nag lossis daus thiab / lossis nce corrosivity.
Cov txheej txheem kuaj rau corrosivity ntawm cov nplai inhibitors tau tsim thiab suav nrog hauv cov ntaub ntawv tswj hwm.Rau txhua daim ntawv thov txuas ntxiv corrosivity kuaj yuav tsum tau ua ua ntej txhaj tshuaj ntawm nplai inhibitor tuaj yeem siv tau.Phom huab tais kev ntsuam xyuas cov tshuaj hauv cov kab txhaj tshuaj kuj tau ua.
Ua ntej pib tsim nyog ntawm cov tshuaj nws yog ib qho tseem ceeb los tsim ib qho kev ua haujlwm uas piav qhia txog cov teeb meem thiab lub hom phiaj ntawm cov tshuaj.Nyob rau theem pib nws yog ib qho tseem ceeb los txheeb xyuas cov teeb meem tseem ceeb kom muaj peev xwm xaiv cov hom tshuaj uas yuav daws tau qhov teeb meem.Cov ntsiab lus ntawm cov txheej txheem tseem ceeb tshaj plaws tuaj yeem pom hauv Table 2.
Kev tsim nyog ntawm cov tshuaj
Kev tsim nyog ntawm cov tshuaj muaj ob qho kev sim thiab kev ntsuas theoretical rau txhua daim ntawv thov.Kev qhia tshwj xeeb thiab cov qauv xeem yuav tsum tau txhais thiab tsim,piv txwv li hauv HSE,khoom compatibility,khoom stability thiab khoom zoo (particles).Ntxiv mus,lub freezing point,viscosity thiab compatibility nrog rau lwm yam tshuaj,hydrate inhibitor,Kev tsim cov dej thiab cov kua dej tsim tawm yuav tsum tau txiav txim siab.Ib daim ntawv teev cov kev sim yooj yim uas tej zaum yuav siv rau kev tsim nyog ntawm cov tshuaj muaj nyob rau hauv Table 2.
Kev tsom mus tas li rau thiab saib xyuas cov kev ua haujlwm zoo,Cov nqi noj tshuaj thiab HSE qhov tseeb yog qhov tseem ceeb.Cov kev xav tau ntawm cov khoom tuaj yeem hloov pauv ntawm thaj chaw lossis cov txheej txheem cog rau lub neej.sib txawv nrog tus nqi ntau lawm nrog rau cov kua muaj pes tsawg leeg.Kev ua haujlwm tom qab nrog kev ntsuas kev ua haujlwm,optimization thiab/lossis kuaj cov tshuaj tshiab yuav tsum tau ua ntau zaus los xyuas kom meej qhov kev kho kom zoo.
Nyob ntawm cov roj zoo,dej ntau lawm thiab cov kev sib tw ntawm cov chaw tsim khoom offshore,kev siv cov tshuaj ntau lawm tej zaum yuav tsum tau ua kom tiav export zoo,kev cai lij choj,thiab ua haujlwm rau kev teeb tsa offshore hauv kev nyab xeeb.Txhua qhov chaw muaj kev sib tw sib txawv, thiab cov tshuaj tsim khoom tsim nyog yuav txawv ntawm thaj chaw mus rau qhov chaw thiab ua haujlwm dhau sijhawm.
Nws yog ib qho tseem ceeb rau kev tsom mus rau kev ua tau zoo ntawm cov tshuaj tsim khoom hauv kev tsim nyog,tab sis nws kuj tseem ceeb heev rau kev tsom mus rau cov khoom ntawm cov tshuaj,xws li stability,khoom zoo thiab compatibility.Compatibility nyob rau hauv qhov teeb meem no txhais tau hais tias compatibility nrog cov kua,cov ntaub ntawv thiab lwm yam khoom siv tshuaj.Qhov no tuaj yeem yog qhov nyuaj.Nws tsis tsim nyog siv tshuaj los daws qhov teeb meem tom qab pom tias cov tshuaj muaj txiaj ntsig los yog tsim teeb meem tshiab.Tej zaum nws yog cov khoom ntawm cov tshuaj thiab tsis yog kev sib tw uas yog qhov kev sib tw loj tshaj plaws.
Cov cai tshwj xeeb
Cov kev cai tshwj xeeb ntawm kev pom cov khoom siv yuav tsum tau thov rau lub subsea system thiab rau kev txhaj tshuaj tas mus li downhole.Cov lim dej thiab cov lim dej hauv cov tshuaj txhaj tshuaj yuav tsum tau muab raws li cov kev qhia tshwj xeeb ntawm cov khoom siv hauv qab los ntawm kev txhaj tshuaj sab saum toj.,twj thiab txhaj li qub,mus rau downhole txhaj li qub.Qhov twg downhole nruam txhaj tshuaj yog siv cov specification nyob rau hauv cov tshuaj txhaj tshuaj system yuav tsum tau raws li cov specification nrog lub siab tshaj plaws criticality.Qhov no tej zaum lub lim ntawm qhov txhaj tshuaj valve downhole.
Txhaj cov nyom
Cov txheej txheem txhaj tshuaj tuaj yeem hais txog 3-50km kev ncua deb ntawm qhov dej ntws hauv dej hiav txwv thiab 1-3km rau hauv qhov dej.Lub cev muaj zog xws li viscosity thiab lub peev xwm los nqus cov tshuaj yog qhov tseem ceeb.Yog tias qhov viscosity ntawm seabed kub siab dhau lawm nws tuaj yeem ua rau muaj kev sib tw rau cov tshuaj los ntawm cov tshuaj txhaj tshuaj hauv subsea umbilical thiab mus rau qhov chaw txhaj tshuaj subsea lossis hauv qhov dej.Lub viscosity yuav tsum yog raws li qhov system specification ntawm kev cia siab los yog ua haujlwm kub.Qhov no yuav tsum tau ntsuas nyob rau hauv txhua rooj plaub,thiab yuav ua raws li qhov system.Raws li lub rooj tshuaj txhaj tshuaj tus nqi yog ib qho tseem ceeb rau kev vam meej hauv tshuaj txhaj tshuaj.Txhawm rau txo qhov kev pheej hmoo ntawm kev ntsaws cov tshuaj txhaj tshuaj,Cov tshuaj nyob rau hauv cov kab ke no yuav tsum tau hydrate inhibited (yog tias muaj peev xwm hydrates).Kev sib xyaw nrog cov kua dej uas muaj nyob hauv lub cev (cov kua dej khaws cia) thiab cov hydrate inhibitor yuav tsum tau ua.Kev ntsuam xyuas kev ruaj ntseg ntawm cov tshuaj ntawm qhov ntsuas kub tiag tiag (tsawg tshaj qhov ntsuas kub ntawm qhov ntsuas kub,ambient kub,subsea kub,txhaj tshuaj kub) yuav tsum dhau.
Ib qho kev pab cuam rau kev ntxuav cov tshuaj txhaj tshuaj ntawm qhov zaus yuav tsum tau txiav txim siab.Nws yuav ua rau muaj kev tiv thaiv kom tsis tu ncua ntawm cov tshuaj txhaj tshuaj nrog hnyav,glycol los yog tshuaj ntxuav kom tshem tawm tau cov deposits ua ntej nws tau sau thiab tuaj yeem ua rau ntsaws ntawm kab.Kev xaiv tshuaj tov ntawm cov kua dej yaug yuav tsum yogtau tshaj cov tshuaj nyob rau hauv cov kab txhaj tshuaj.
Qee zaum cov tshuaj txhaj tshuaj yog siv rau ntau yam kev siv tshuaj lom neeg raws li cov kev sib tw sib txawv hauv lub neej thiab cov dej hauv cov dej.Nyob rau hauv thawj theem ntawm kev tsim khoom ua ntej dej tawg cov teeb meem tseem ceeb tuaj yeem sib txawv ntawm cov neeg nyob hauv lub neej lig feem ntau cuam tshuam txog kev tsim cov dej ntau ntxiv.Txhawm rau hloov los ntawm non-aqueous hnyav raws li inhibitor xws li asphalt ene inhibitor rau dej raws cov tshuaj xws li nplai inhibitor tuaj yeem ua rau muaj kev sib tw nrog kev sib raug zoo.Yog li ntawd nws yog ib qho tseem ceeb uas yuav tsum tau tsom mus rau kev sib raug zoo thiab kev tsim nyog thiab kev siv cov spacers thaum npaj los hloov cov tshuaj hauv cov tshuaj txhaj tshuaj.
Khoom siv
Hais txog cov khoom compatibility,tag nrho cov tshuaj yuav tsum sib haum nrog cov ntsaws ruaj ruaj,elastomers,gaskets thiab cov khoom siv siv hauv cov tshuaj txhaj tshuaj thiab cov chaw tsim khoom.Cov txheej txheem kuaj rau corrosivity ntawm cov tshuaj (xws li acidic scale inhibitor) rau kev txhaj tshuaj tas li yuav tsum tau tsim.Rau txhua daim ntawv thov txuas ntxiv corrosivity kuaj yuav tsum tau ua ua ntej txhaj tshuaj tuaj yeem siv tau.
Kev sib tham
Qhov zoo thiab qhov tsis zoo ntawm kev txhaj tshuaj tsis tu ncua downhole yuav tsum tau soj ntsuam.Kev txhaj tshuaj tsis tu ncua ntawm nplai inhibitor los tiv thaiv DHS Vor cov tubing ntau lawm yog ib txoj hauv kev zoo nkauj los tiv thaiv lub qhov dej ntawm nplai.Raws li tau hais hauv daim ntawv no muaj ntau qhov kev sib tw nrog kev txhaj tshuaj tsis tu ncua downhole,txawm li cas los xij kom txo tau qhov kev pheej hmoo nws yog ib qho tseem ceeb kom nkag siab txog qhov tshwm sim txuas nrog kev daws teeb meem.
Ib txoj hauv kev los txo qhov kev pheej hmoo yog tsom mus rau kev sim txoj kev txhim kho.Piv rau topside lossis subsea tshuaj txhaj tshuaj muaj qhov sib txawv thiab hnyav dua hauv lub qhov dej.Cov txheej txheem tsim nyog rau cov tshuaj rau kev txhaj tshuaj tas mus li ntawm cov tshuaj downhole yuav tsum tau xav txog cov kev hloov pauv hauv cov xwm txheej no.Kev tsim nyog ntawm cov tshuaj yuav tsum tau ua raws li cov khoom siv uas cov tshuaj yuav tau ntsib nrog.Cov kev cai rau kev tsim nyog rau kev sib raug zoo thiab kev sim ntawm cov xwm txheej uas rov ua dua li ze li qhov ua tau ntawm ntau yam kev ua neej nyob hauv cov txheej txheem no yuav ua haujlwm raws li yuav tsum tau hloov kho thiab siv.Txoj kev xeem txoj kev txhim kho yuav tsum tau tsim ntxiv mus rau ntau qhov tseeb thiab cov kev xeem sawv cev.
Ntxiv rau,kev sib cuam tshuam ntawm cov tshuaj thiab cov khoom siv yog qhov tseem ceeb rau kev ua tiav.Kev loj hlob ntawm cov tshuaj txhaj tshuaj li qub yuav tsum tau ua tib zoo xav txog cov khoom siv tshuaj thiab qhov chaw ntawm qhov txhaj tshuaj valve hauv qhov dej.Nws yuav tsum raug suav hais tias suav nrog cov tshuaj txhaj tshuaj tiag tiag ua ib feem ntawm cov khoom siv ntsuas thiab ua kom tau txais kev ntsuas kev ua tau zoo ntawm cov nplai inhibitor thiab valve tsim raws li ib feem ntawm kev tsim nyog.Yuav kom tsim nyog scale inhibitors,Lub hom phiaj tseem ceeb tau ua dhau los ntawm cov txheej txheem kev sib tw thiab kev ntsuas qhov ntsuas,tab sis zoo scale inhibition nyob ntawm ruaj khov thiab nruam txhaj tshuaj.Yog tsis muaj kev ruaj khov thiab tsis tu ncua kev txhaj tshuaj lub peev xwm rau nplai yuav nce.Yog hais tias tus nplai inhibitor txhaj valve yog gunk ed thiab tsis muaj scale inhibitor txhaj rau hauv cov kua dej.,lub qhov dej thiab kev nyab xeeb li qub tsis muaj kev tiv thaiv los ntawm nplai thiab yog li kev tsim khoom nyab xeeb yuav raug puas tsuaj.Cov txheej txheem tsim nyog yuav tsum tau saib xyuas cov teeb meem cuam tshuam nrog kev txhaj tshuaj ntawm cov nplai inhibitor ntxiv rau cov txheej txheem kev sib tw thiab kev ua tau zoo ntawm kev tsim nyog scale inhibitor.
Txoj hauv kev tshiab no suav nrog ntau qhov kev qhuab qhia thiab kev koom tes ntawm kev qhuab qhia thiab cov luag haujlwm uas yuav tsum tau qhia meej.Nyob rau hauv daim ntawv thov no topside txheej txheem system,subsea templates thiab zoo tsim thiab ua tiav yog koom tes.Kev cob qhia ntau lub koom haum tsom mus rau kev tsim cov kev daws teeb meem zoo rau cov tshuaj txhaj tshuaj yog qhov tseem ceeb thiab tej zaum txoj hauv kev ua tiav.Kev sib txuas lus ntawm ntau yam kev qhuab qhia yog qhov tseem ceeb;tshwj xeeb tshaj yog nyob ze kev sib txuas lus ntawm cov kws tshuaj uas muaj kev tswj cov tshuaj siv thiab cov engineers zoo uas muaj kev tswj cov khoom siv hauv qhov dej yog qhov tseem ceeb.Txhawm rau nkag siab txog cov kev sib tw sib txawv thiab kawm los ntawm ib leeg yog qhov tseem ceeb kom nkag siab txog qhov nyuaj ntawm tag nrho cov txheej txheem.
Xaus
● Kev txhaj tshuaj tsis tu ncua ntawm nplai inhibitor los tiv thaiv DHS Vor cov tubing ntau lawm yog ib txoj hauv kev zoo nkauj los tiv thaiv lub qhov dej rau nplai
● Txhawm rau daws cov teeb meem uas tau txheeb xyuas,cov lus pom zoo hauv qab no yog:
● Yuav tsum tau ua raws li DHCI kev tsim nyog.
● Txoj kev tsim nyog rau cov tshuaj txhaj tshuaj li qub
● Kev sim thiab kev tsim nyog rau kev ua haujlwm tshuaj lom neeg
● Kev txhim kho txoj kev
● Kev ntsuam xyuas cov khoom siv
● Kev sib cuam tshuam ntau qhov kev qhuab qhia uas kev sib txuas lus ntawm ntau yam kev qhuab qhia koom nrog yog qhov tseem ceeb rau kev ua tiav.
Kev lees paub
Tus sau xav ua tsaug rau Statoil AS A rau kev tso cai luam tawm cov haujlwm no thiab Baker Hughes thiab Schlumberger tso cai siv cov duab hauv Fig.2.
Nomenclature
(Ba / Sr) SO4 = barium / strontium sulfate
CaCO3 = Calcium carbonate
DHCI = downhole tshuaj txhaj
DHSV = downhole kev nyab xeeb valve
eg = np
GOR = roj av ratio
HSE = ib puag ncig kev nyab xeeb
HPHT = siab kub siab
ID = puab diam
ie = yog
km = km
mm = hli
MEG = Mono ethylene glycol
mMD = meter ntsuas qhov tob
OD = sab nraud
SI = scale inhibitor
mTV D = meter tag nrho ntsug qhov tob
U-tube = U-shaped tube
VPD = vapor pressure depressant
Daim duab 1. Txheej txheem cej luam ntawm subsea thiab downhole tshuaj txhaj tshuab nyob rau hauv atypical teb.Sketch ntawm tshuaj txhaj tshuaj nce kwj DHSV thiab cov kev sib tw uas xav tau.DHS V = downhole safety valve, PWV = process wing valve and PM V = process master valve.
Daim duab 2. Sketch ntawm atypical downhole tshuaj txhaj system nrog lub mandrel thiab valve.Lub kaw lus yog hooked mus rau saum npoo manifold, pub los ntawm-thiab txuas nrog lub tubing hanger ntawm lub annular sab ntawm lub tubing.Cov tshuaj txhaj tshuaj mandrel yog ib txwm muab tso rau hauv qhov tob hauv qhov dej nrog lub hom phiaj los muab tshuaj tiv thaiv.
Daim duab 3. Hom zoo barrier schematic,qhov twg cov xim xiav sawv cev rau lub hnab ntawv lub hauv paus zoo;nyob rau hauv cov ntaub ntawv no ntau lawm tubing.Cov xim liab sawv cev rau lub hnab ntawv thib ob;lub casing.Nyob rau sab laug yog qhia cov tshuaj txhaj tshuaj, blackline nrog txhaj tshuaj taw tes rau cov tubing ntau lawm hauv cheeb tsam cim liab (thib ob qhov teeb meem).
Daim duab 4. Pitted qhov pom nyob rau sab sauv ntawm 3/8 "txoj kab txhaj tshuaj.Lub cheeb tsam tau pom nyob rau hauv daim duab kos duab ntawm atypical zoo barrier schematic, cim nrog txiv kab ntxwv ellipse.
Daim duab 5. Kev tawm tsam hnyav ntawm 7 "3% Chrome tubing.Daim duab qhia txog kev tawm tsam corrosion tom qab nplai inhibitor txau los ntawm cov tshuaj pitted tshuaj txhaj rau ntawm cov tubing ntau lawm.
Daim duab 6. Cov khib nyiab pom nyob rau hauv cov tshuaj txhaj tshuaj valve.Cov khib nyiab nyob rau hauv rooj plaub no yog hlau shavings tej zaum los ntawm cov txheej txheem installation ntxiv rau qee cov khib nyiab dawb.Kev tshuaj xyuas ntawm cov khib nyiab dawb ua pov thawj tias yog cov polymers nrog cov tshuaj zoo sib xws li cov tshuaj txhaj tshuaj
Post lub sij hawm: Apr-27-2022