|
n
<br />LJ
<br />prnsibility of the process soot movinj upward. Within
<br />the process intwal, the nahcolite content varier signifi-
<br />cantly (from 0.5 m 80 6 wtieht ptrcent) with relatively
<br />lean submler v;r6 Of appfe[iablc vutical eetcm (a6mrt
<br />14 (t of 8.3-weight-pueent ttahcolitc, about 16 ft of
<br />2 O weight-puexnt nlhCOlife). Likewise, the oil rnntrnl
<br />varies from 5.8 to u Aijh as 49.6 gal/ton. Avengt oil
<br />assay and nahcolitc Contort ovc the chosen process in-
<br />terval are 24 gal/ron and 26 sveijhl perCenf, tepectivdy.
<br />Well Compktfore
<br />Design considentioru for the welts included ability to
<br />inter~lange the roles of produnion and injection wtlla,
<br />m'cManical stratgdt to withsund the movement of Rla-
<br />tivelylarge pieces of rvbblc,ability [0 opaatc at tempen-
<br />ares u hljh u 632 'F, and ahrliry to ududc oil-shalt
<br />sdtunks from the produced stream.
<br />The first well drilled to evalwtc the zone wu com-
<br />pleted u a temperarure observation well with SK-in.,
<br />17•Ib, N•80 cuing to a depth of 2,000 ft, with heat-
<br />resit[ent ecmrnt from bonnm ro 1,20() fi. l7fc unusually
<br />large cuing in the obsmation well wu to allow tht use
<br />of special lojging tools u well u to provide flexibility
<br />for possible conversion to a producer-injrrttsr. In and
<br />nw the process zone, Hydril joints with HCS Ihreadc
<br />were used IO provide added ehcngdl during possible
<br />thumal cycling as well u to provide she stronger[ pt7ssi-
<br />blcjoint eompressivestrength.
<br />Botha 7-in production cuing end a 5'h in., 17-Ib,
<br />N•BO injecion cuing were cemented in the second hole
<br />AVEIIAGE VALUES
<br />wr-t pt••• On •q
<br />H."co> rett ut.ir~
<br />t BOO . -
<br />_r - n.a
<br />•trso-
<br />Irk 2:.7
<br />^ns = - -
<br /> os .•.
<br /> sr o - nr
<br /> -" ieac
<br /> l1f .t1•
<br />Ts-y - ~.
<br />a.r 7Jo
<br />s • >~
<br />xr r 77A
<br />-suo-
<br />7.0 - er..
<br />r~1= J
<br />7x7
<br />rte
<br />ess
<br />..x
<br />~~~
<br />u7e
<br />ie>v
<br />isle
<br />A9. tz-Strtamat:c dai7rani o~ to.+!rsas aro of runCetna aro
<br />tarnpan mntsrnf Ir, and nae~ en PM.R nrbrval.
<br />SCYfEMBFR. IY.'1
<br />from near the top o(tttrorns intcrral to surface usinj
<br />hat resistant cement. Thc pen of the production cuing
<br />below the top of the process tnterval was 7-in., 38-ID.
<br />N-80 casing, wh:d1 hung into 7 sump that cstcndcd wdl
<br />bctow the process Inttrial. At an DC aeon ut the sche-
<br />matic represenution of the cvrrtplctioru !n the process
<br />interval given in Fitt 12, the using w-as upped on
<br />bottom and had a ISft clotted esction from 1,863 to
<br />1878 fr.
<br />Thc bort}~Ne wu wsderrramcd m 24 m. in the process
<br />intcal.'Ihc annulus between the production acing and
<br />[hc borehole served 10 provide the initial COmmuniCatiOn
<br />for the iajtcfion Iluida, and uposod the tati7e process
<br />interval to Iaaching. (All ddlGng and cireulaGon fluids
<br />turd in the process interval were prcaatunted with
<br />aOdium biarbonate.) Steam wu iajecad through insu-
<br />lated and prestressed 2tii-In. abinj.
<br />pratrs5scd and insulatul 3'h-in. tubinj was usod for
<br />production, wid+ a [Onet7ttri: 2-1116-in. string used for
<br />diluttnj and cruslinj the prtsduttion strum. Nicogen in
<br />dtc 355- to 7-in. annulus provided bottom-hole pressure
<br />s:7u.surtmcnu.
<br />Four Lhcrmt7muples were s'-apped b the 7•m. erring,
<br />two a 1,7)9 ft and two a[ 1,851 p
<br />Subsequent operations resu:trA in tnodlfations to the
<br />Nbinj strings and other equ:pmcnt used in the SVt- and
<br />7. in casings, both with regard w insulation, prestrus-
<br />inj,and t; pe of stttl. Most o(the f cld test opcyted with
<br />the equipment as described, and the tubing sixes were
<br />nott~tang-:.'.
<br />Opentioru
<br />Durinr [h: inl[ial Inching phast, wato was mlcclyd at
<br />wrfacc tcrtspuatures of 60, 150, and 250 'F, from Lan.
<br />18, 1971, to March 6, 1971. As un be seen from the
<br />eumnury or Operations giver. in Fig. ! 3, three were four
<br />distinct siwm-injection oil-production pciods, with the
<br />Iasl dtree Oct ignrd to nice; sprtific opcating problems
<br />cncountc :d during the coup: of the freed test.
<br />The luting plant was tcrstinated after 44 days Of
<br />water injecion and the productitn of 121,000 Ib of mh-
<br />rolite. This gave ^n equivalc.n; pvity radius of 7 ft. The
<br />nujor ftndinj during the lashing phue wu Lie effi-
<br />ciency of Ne hot water in Ic1 sine nah.blitc.
<br />LiquiC head surveys run on De:. 8, 1970, bdote
<br />ladling s3rtal, indicatuf tha: there had been no Itaeh-
<br />injduring the underteaming end eompletias opcntit7ns-
<br />A survey run rm Feb. 8, 1971, indigrtd rso tingle cub-
<br />inraval was cono-ibuting abnsmally w dte shape of the
<br />avity. These wrvcys were carried out by bbwing the
<br />cavity dry, idling the cavil; incrtmcntally wish a iat-
<br />trit~ sol~Kion of nahrolite, and measuring both the fluid
<br />Icvcl in Lhc 3K-in tubing sod the inc~eue in bonom-
<br />IfAle prsssurc.
<br />Thc avcrajc tcmperaarrc ssithin the process volume,
<br />which wss Obtained from in:cpreution of the available
<br />tcntpaacirc mCacur_mcnn,s also shown b Fig 13.
<br />Phase l o.' tAe steam inJecuoo-rabvexy period started m
<br />Accede 6 and tantinutd to April ti, 19-11 f4r7gram objcc-
<br />[ivrs of a t:mperawre of 625'F a [hcinjection point and
<br />a bottom-hole tcmpcnrurc range of 450 to 550 'F wee
<br />tv inninn! over amts too shy: to ohoin preduttion-
<br />7he 3w~in. pttxluction n:bing plugged twice during
<br />plsasc ]. iltc lust plug, whni ronsv:al of prttipiuted
<br />IOaS
<br />` ~~~~
<br />Q°~Y ,~J
<br />~~~
<br />1 'off
<br />V
<br />
<br />
|