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1 SUMMARY OF RESULTS OF HGPA WELL TESTNG D. Kihara, B. Chn, P. Yun, and P. Takahashi Univrsity of Hawai i Honolulu, Hawaii Th xprimntal wll, HGPA, drilld undr th auspics of th Hawaii Gothrmal Projct, is locatd on th island of Hawaii nar th astrn rift of Kilaua volcano. Drilling was compltd to a dpth of 645 ft in April Th wll is casd to 223 ft blow th surfac, which is 6 ft abov sa lvl, with a slottd linr running from th nd of th casing to bottomhol. Cuttings and cor sampls obtaind during drilling indicat that th rgion is composd of volcanic basalt with a rofil that contains a zon of opn fracturs (33945 ft P and a zon of partially sald fracturs (45645 ft) as shown in Figur 1. Th wll has undrgon fiv flash discharg tsts sinc an initial flashing on July 2, Th maximum bottomhol tmpratur during quiscnt priods has bn masurd at 358 C. Tst watr sampls wr takn at various tims undr varying flow conditions and analyzd. Th mdian valus for th downhol sampls ar shown in Tabl 1. TABLE 1 HGPA Gochmical Summary PH Elctrical conductivity Salinity Chl ori d Silica as Si2 Su 1 f i d Sodi um Potassi um Cal ci um Magns i um Tritium Lss than 5 31 p.mho/cm 2 3"/ 925 mg/l 42 mg/l 1 mg/l 6 mg/l 123 mg/l 4 mg/l 1 mg/l Lss than.1 tritium unit or at last 12 yars old t is sn that th HGPA discharg is a slightly salin watr containing about 5% ocan watr but with fairly high silica contnt. Following installation of th sparatorsilncr, flow tsts wr run in Novmbr, Dcmbr, January, and March. n th last thr cass, prssur buildup tsts wr conductd aftr th wll was shut in. 1 38

2 > CY u! J V W > 4 CY W cl x aj LL SEA LEVEL SUBAERAL VOLCANCS $! SUBAER ALSUBMAR NE TRANSTON LARGELY UNALTERED SUMAR NE VOLCAN CS 1 :! ; i t i : L! i~ : 1 1 : : ' HYDROTHERMALLY ALTERED SUBMARNE VOLCAN CS m] BASALTC AND PAHOEHOE FLOWS 1 1.'. BASALTC CNDER AND SPATTER SUBMAR NE BASALT ' FLOWS AND P LLOWS b\y,'l COMPLETELY TO PART ALLYSEALED FRACTURE SYSTEMS Sourc:. Palmitr FGURE 1, HGPA LTHOLOGC LOG FROM CORES AND CUTTNGS 139

3 Comparison of flow charactristics during th arly stags of ths four tsts (Tabl 2) shows that with ach subsqunt tst th flow rat has incrasd. A possibl xplanation for this improvmnt in wll prformanc is that skin damag du to th us of drilling mud is bing allviatd as ach flow tst partially clans out mbddd mud. Tabl 2 COMPARSON OF DSCHARGE TESTS AT 25 HOURS AFTER NTATON OF FLOW Nov. Dc. Jan. Mar. W1 1 had Prssur (psig) W1 1 had Tmpratur ("C) Lip Prssur (psig) Wir Hight (inchs) Mass Flow Rat (Klb/hr) Watr Flow Rat (Klb/hr) Stam Flow Rat (Klb/hr) Stam Quality (%) Enthalpy (BTU/lb) Thrmal Powr (Mw) / / / ' 29.7 Th January and March flow tsts consistd of sris of dischargs in which th flow was throttld by placing orific plats of various sizs in th discharg lin. Th rsults ar summarizd in Tabl 3. Thr is a substantial incras in wllhad prssur from 51 psig to 375 psig as th mass flow rat is rducd from 1% or 11 Klb/hr to 75% (76 Klb/hr) of wid opn flow. Orific Siz (nchs) / /4 Tabl 3 PRELMNARY THROTTLED FLOW DATA Total Mass Stam W1 1 had Flow Rat Flow Rat Quality Prssur Tmp. (Klb/hr) (Klb/hrl (%) (psig) (OF) Poss i bl Elctrical Powr Output '( MW ) Th lctrical powr output possibl from ths flow conditions was calculatd assuming a turbingnrator fficincy of 75% as th stam xpands from wllhad prssur to a back prssur of 1 4

4 4 inchs of mrcury. Thr is a broad powr output maximum of 3.3 to 3.5 MW ovr a rang of wllhad prssurs from 5 to 237 psig. This rang will allow a wid latitud in th dsign of a wllhad gnrator systm. Prssur and tmpratur profils takn during th throttld flow tsts in January ar shown in Figurs 2 and 3. Ths profils indicat that th fluid in th wllbor is at saturation conditions with a mixtur of liquid and vapor flowing up to th wllhad, that is, with flashing occurring in th rsrvoir. Also shown in Figur 3 is th tmpratur profil 25 days aftr th wll was shut in (zro flow rat). Examination of Figur 2 shows that th prssur profils ar ssntially thr constant slop lins mting at th junction of th casing and slottd linr and at approximatly 43 ft. Ths constant prssur gradint lins indicat that th major production zons ar nar bottomhol and in th vicinity of 43 ft. Som limitd information about th rsrvoir can b obtaind by utilizing th thory for oil and gas wlls. Ths standard ptrolum nginring tchniqus, howvr, assum singl phas flow, whil th flow in HGPA is dfinitly twophas, so that xtrm caution is rquird in intrprting th rsults of ths analyss. Foll owing th Dcmbr discharg, a prssur bui 1 dup tst was conductd, with bottomhol prssur bing masurd using two Kustr KPG prssur lmnts and rcordrs in tandm to nsur that prssur data wr acquird in spit of quipmnt malfunction bcaus of th high tmpratur. Figur 4 is a loglog typ curv of th diffrnc btwn bottomhol prssurs during static (no flow) and flow conditions. t shows two distinct wllbor storag ffcts; th top of th scond wllbor storag intrval is indicatd by th arrow A. Arrow B indicats th onst of th radial flow priod, roughly 7 hours aftr th wll is shut in. From ths curvs, th product of prmability and production zon thicknss (kh) is calculatd to b approximatly 88 mill idarcyft, with th prssur drop across th muddamagd skin of th w1 1 bing 56 psi. Bottomhol prssur masurmnts mad aftr HGPA was shut in following th January tst producd data and plots similar to thos for th Dcmbr tst. Howvr, clos xamination of th data shows that two conscutiv straightlin approximations may b mad to th Hornr plot (Figur 5). ntrprtation of this occurrnc is that thr ar at last two diffrnt production layrs in th wllbor with diffrnt kh valus. Th sam ffct is also prsnt in th Dcmbr data, but until it was rproducd in th January tst, littl crdnc was givn to it. Th rsults of ths analyss ar summarizd in Tabl

5 Tmprotur in OC Prssur in Psig P N c. f 34 i O F 2 f 3 9. c f n ~ Stam Flow in KWHr c P3l 5 FGURE 2. PRESSURE PROFLES FOR HGPA Tmpratur in OF Stam Flow in Klb/Hr 7 M 66 c FGURE 3, TEMPERATURE PROFLES FOR HGPA

6 Tlm, hr FGURE 4. LOGLOG PLOT OF DECEPBER PRESSURE BULDUP TEST DATA?+At At FGURE 5. JAtWARY/FEBRtiARY PEESSURE BULDUP TEST 143

7 Tabl 4 COMPARSON OF PRESSURE DRAWDOWN AND BULDUP TESTS Constant Production Dcmbr Buildup January Buildup Prmabi 1 i ty thicknss, kh, mdft Drawdown 1356 On Layr 88 Two Layr 1553 Two Layr 189 Apparnt skin factor, s Prssur drop across skin, psi Flow fficincy Thr is a substantial problm associatd with th dposition of scal, primarily from dissolvd silica. As an xampl, th mufflr that was installd uss an annular rgion filld with cindrs as a soundabsorbing agnt. Howvr, aftr only 16 days of flow, th scal dpositd was sufficint to cmnt th cindrs togthr so that rmoval rquird xtnsiv chipping of th bound cindrs. A summary of th rsults of tsts thus far is prsntd in Tabl 5. Tabl 5 SUMMARY OF PRELMNARY TEST RESULTS AND ANALYSES Kapoho Gothrmal Rsrvoir 1. Liquiddominatd 2. Tight Formation: Prmability Thicknss % 1 mdft Vry High Tmpraturs 'L 35 C High Formation Prssur 2, 2 psi 5. Slightly Brackish Watr 6. Potntially Larg Rsrvoir 7. High Silica Contnt HGPA Gothrmal Wll 1. During Flash Borhol Contains Stam and Watr at Saturation 2. Flashing Occurs in Formation 3. High Wllhad Prssurs % 16 psi at 5 Klb/hr Stam 4. Producing Rgions Probably at Bottomhol and 43 Ft 5. Probably Has Svr Skin Damag 6. Potntial Powr Output % 3.5 MW 7. Flows Hav ncrasd with Each Tst 1 44

Principles of Humidity Dalton s law

Principles of Humidity Dalton s law Principls of Humidity Dalton s law Air is a mixtur of diffrnt gass. Th main gas componnts ar: Gas componnt volum [%] wight [%] Nitrogn N 2 78,03 75,47 Oxygn O 2 20,99 23,20 Argon Ar 0,93 1,28 Carbon dioxid