Kev Txhim Kho Geothermal System Siv Roj Thiab Roj Technology los ua kom kuv cov pa roj carbon tsawg. Ntu 2.

US Department of Energy (DOE) tau pab nyiaj rau ib txoj haujlwm hu ua FORGE qhov kub granite pob zeb yuav raug drilled thiab fracked siv cov roj thiab roj zoo tshaj plaws technology. Lub hom phiaj zuag qhia tag nrho yog saib yog tias cov dej ntws los hauv ib qhov dej tuaj yeem xa mus los ntawm granite thiab ua kom sov ua ntej tso dej thib ob los tsav turbines uas tsim hluav taws xob.

John McLennan, Department of Chemical Engineering, University of Utah, yog tus thawj coj tshawb nrhiav rau qhov DOE project. Kev nthuav qhia webinar ntawm lub ncauj lus no tau txhawb nqa los ntawm NSI thaum Lub Plaub Hlis 6, 2022: FRontier Observatory rau Kev Tshawb Fawb Hauv Geothermal Zog (FORGE): Kev Hloov Kho thiab Saib Ua Ntej

Ntu 1 tau teb cov lus nug no rau John McLennan:

Q1. Koj puas tuaj yeem muab keeb kwm luv luv ntawm geothermal zog?

Q2. Dab tsi yog kev txhim kho geothermal systems, thiab qhov twg fracking siv?

Q3. Qhia peb txog qhov chaw ntawm FORGE project hauv Utah thiab vim li cas nws thiaj raug xaiv.

Cov ntawv sau no yog Ntu 2, uas hais txog peb nqe lus nug ntxiv hauv qab no:

Q4. Dab tsi yog qhov tsim qauv ntawm kev txhaj tshuaj thiab cov qhov dej ntau lawm?

Rau lub qhov dej tau raug drilled rau hnub no. Tsib lub qhov dej no yog vertically drilled xyuas qhov dej, uas yog raws li lub tswv yim ntawm kev ua ib lub chaw soj nstuam. Fiber optic cables thiab geophones nyob rau hauv lub qhov dej saib xyuas tuaj yeem qhia txog kev loj hlob ntawm cov hydraulic fractures interconnecting ib tug txhaj tshuaj zoo, uas tau raug drilled, thiab ib tug tom ntej no ntau lawm zoo.

Lub qhov dej txhaj tshuaj tau drilled mus rau qhov ntsuas qhov tob ntawm 10,987 ft (qhov tseeb ntsug qhov tob ntawm 8520 ft ± hauv qab av). Qhov no entailed drilling vertically thiab tom qab ntawd tsim ib qho nkhaus ntawm 5 ° / 100 ft drilled, thiab thaum kawg tuav ib sab ntawm 65 ° mus rau ntsug, txog li 4,300 ko taw hauv azimuth sab qab teb ntawm sab hnub tuaj (N105E). Cov kev taw qhia no nyiam cov hydraulic fractures tom ntej yog orthogonal rau lub qhov dej.

Tom qab drilling, tag nrho tab sis hauv qab tshaj 200 ft ntawm lub qhov dej tau raug kaw (ntau txoj kab uas hla 7-nti casing tau siv los txav cov dej ntau nrog kev sib txhuam thiab cov cab cab losses) thiab cemented rau saum npoo (rau hydraulically cais qhov chaw annular) .

Q5. Koj puas tuaj yeem hais txog peb txoj kev kho mob frac hauv kev txhaj tshuaj zoo thiab lawv cov txiaj ntsig?

Thaum lub Plaub Hlis 2022, peb lub pob txha hydraulic tau muab tso ze rau ntawm qhov qis qis (tus ntiv taw) ntawm qhov kev txhaj tshuaj zoo. Geophones nyob rau hauv peb lub qhov dej, qhov ntsuas qhov chaw, thiab downhole fiber optic sensors muab ib tug saib ntawm evolving pob txha geometries thaum lub sij hawm siv. Raws li kev txhais ntawm cov pob txha geometries, cov khoom tsim tau zoo tom ntej yuav raug laum los cuam tshuam cov huab ntawm microseismicity.

Peb theem tawg tau txuas txuas ntxiv mus. Thawj zaug tsom tag nrho qhov qhib qhov ntev ntawm qhov dej (qhov qis dua 200 ko taw uas tsis tau raug kaw). Qhov kev kho ntawd yog slickwater (kev sib txhuam-txo dej). 4,261 bbl (~ 179,000 gal) tau nqus ntawm tus nqi mus txog 50 bpm (2100 gpm). Tom qab kaw luv luv, lub qhov dej tau ntws rov qab ntawm qhov kub ntawm li 220 ° F.

Cov theem tom ntej no koom nrog kev siv dej slickwater ntawm tus nqi txog li 35 bpm los ntawm 20-ft ntev ntu ntawm cov casing uas tau raug perforated nrog 120 tus nqi them los muab kev nkag mus rau kev tsim los ntawm cov casing thiab cov cement sheath. 2,777 bbl ntawm slickwater tau pumped; thiab tom qab ntawd lub qhov dej tau ntws rov qab.

Qhov kawg theem entailed 3,016 bbl ntawm crosslinked (viscosified) kua pumped los ntawm perforated casing ntawm tus nqi mus txog 35 bpm. Micropropant tau muab tso rau. Nyob rau hauv lub neej yav tom ntej, kev ntsuam xyuas yuav tsum tau ua los ntsuas qhov tsim nyog thiab muaj peev xwm ntawm propping fractures kom ntseeg tau tias conductivity ntawm cov pob txha tsim.

Kev ua haujlwm ua ntej ntawm theem thib peb qhia txog kev loj hlob ntawm pseudo-radial tawg, nyob ib ncig ntawm lub qhov dej ntawm qhov chaw. Qhov no nyiam kev sib cais ntawm cov tshuaj uas twb muaj lawm thiab cov neeg tsim khoom yav tom ntej ntawm qhov kev txiav txim ntawm 300 ft. Ib qho kev lag luam scenario yuav xav tau ntau dua offset dua qhov no; Txawm li cas los xij, qhov kev sim no yuav tsum xub tsim kom muaj peev xwm sib txuas ob lub qhov dej uas nyob ib sab nrog hydraulic fracturing.

Q6. Lub peev xwm rau kev lag luam thov yog dab tsi?

Hauv kev lag luam teeb tsa, ntau qhov sib txawv ntawm cov hydraulic tawg yuav raug tsim los cuam tshuam cov qhov dej. Nyob rau ntawm FORGE lub chaw soj nstuam, qhov ntev ntawm sab nraud yuav mob siab rau kev sim cov thev naus laus zis tshiab. Cov no suav nrog cov txheej txheem rau kev txiav txim siab cov yam ntxwv ntawm lub pas dej, hydraulic fracturing thiab perforating cov tswv yim, conformance - nominally sib npaug ntws los ntawm txhua qhov hydraulic tawg, thiab cov yam ntxwv ntawm circulating los ntawm cov pob txha sib txuas thiab tus nqi ntawm thermal depletion tau ntsib. Cov ntawv cog lus tshawb fawb tau tso cai rau lwm tog neeg (cov tsev kawm qib siab, cov chaw sim hauv tebchaws, cov chaw tsim khoom) los tsim cov thev naus laus zis thiab sim lawv tawm ntawm FORGE.

Hauv kev lag luam EGS teeb tsa, dej txias yuav raug txhaj thiab dhau los ntawm cov khoom siv hydraulically tsim cov pob txha, tau txais cov cua sov hauv cov txheej txheem. Cov dej kub yuav raug tsim los ntawm qhov chaw tsim khoom. Nyob rau saum npoo, txheej txheem geothermal thev naus laus zis yuav raug siv rau kev tsim hluav taws xob (ib qho organic Rankine voj voog (ORC) cog, siv cov kua dej ua haujlwm thib ob uas yog flashed rau vapor los tsav lub turbine / generator; lossis, ncaj qha flashing rau chav). Cov dej uas tsim tawm, tom qab cua sov tau muab tshem tawm, yog rov ua dua.

Lub vev xaib FORGE yuav tsis yog tus tsim hluav taws xob. Nws yog npaj los siv los sim thiab tsim cov thev naus laus zis uas yuav txhawb nqa kev lag luam ntawm hom hluav taws xob hluav taws xob hauv qab no. Kev vam meej nyob ib ncig ntawm kev txhim kho technology. Twb tau, kev nce qib tseem ceeb tau ua los ntawm kev txhawb nqa daim ntawv thov ntawm polycrystalline pob zeb diamond compact bits (PDC) uas ua rau muaj kev nce ntxiv hauv cov nqi nkag. Kev soj ntsuam cov txheej txheem ntawm kev ntsuas subsurface thiab kev cob qhia ntawm txhua tus neeg ua haujlwm hauv qhov chaw rig tau txhim kho kev lag luam drilling ntawm qhov project geothermal.

Nws zoo nkaus li tias hydraulic fracturing tuaj yeem ua tau zoo - tab sis qhov kev sim tiag tiag nyob hauv kev ua haujlwm zoo thiab rov ua kom sov tom qab lub qhov dej tau drilled.

EGS kev vam meej ntawm no tuaj yeem siv rau lwm qhov. Xav txog kev siv hydraulic fracturing rau hybrid EGS daim ntaub ntawv qhov twg cov pa siv tau ntsib cov geothermal sib npaug ntawm lub qhov qhuav - ntuj tawg tsis tau ntsib thaum lub sij hawm drilling tab sis tuaj yeem cuam tshuam los ntawm kev tawg.

Kev vam meej ntawm FORGE txhais tau hais tias kev sim cov thev naus laus zis uas yuav tsis raug txiav txim siab, dhau cov thev naus laus zis siv tau rau kev lag luam ntiag tug, thiab txhawb nqa kev txhim kho hauv ntiaj teb tag nrho.