Ukuthintana Kwamandla Okubhala Ngokushesha Kwe-LNG

Ukuncane Okuphakanyiswa Kuqondile

I-Liquefied natural gas ifika emathimbaleni okufaka e-izwe ngokuphakanyiswa ku-162°C. Lokhu kukho amandla okuncane angaphezulu—ukuncane okunegcinwe ngokusebenzisa umsebenzi wokuphakanyiswa ngokwesibonelo. Kodwa amathimbaleni a-manyana ase-LNG ayisebenzisa kuphela i-LNG ngokuvutha ngaseawater noma ngokusebenzisa amafutha esikhangeli, futhi abuyisela lokhu ukuncane kumhlaba. Akukho mthwalo ukubona amasiteki akusebenzisa lemandla njengokuthi kuyinto eyodwa eyenziwa ngokuzenzakalela, nakuba yilokho okungabikho kakhulu kwezindawo zokusebenza kwezindustria zokusebenza kwezinye izinhlanganiswano.

Izinhombolo zizibiza indaba engekho yonke. Isitayela sokubuyisela i-LNG esikhulu sokuqondisa amakhilogramu amaningi kusasa ngonyaka ishuma umthelela wokuhlula okuncane okufanana nokuthenga amakhilowathi amashumi emisebenzi yokuphatha amandla. Lokho umthelela akasukela ngomphakathi—ukugcina ukuthi kwenza i-LNG kushintsha ngokuphelele ama-8% ku-10% we-gas yenkampani njengomthelela wokusebenza. Ukuvumela lokho umthelela wokuhlula ukuba uhlale ungathathelwa kungaba yindlela yokuhlela imali, ngokujabuliswa kwe-exergy.

Yini okwenza umthelela wokuhlula we-LNG ubuhle bakithi

Amaphuzu okuhlula okuncane ayisifundiswa ngokuphelele. Ukususa izigwinya zokuhlanzwa kwesinye, ukuproducwa kwe-ethylene, ukugcina okuncane, futhi ukuchitha kwezindawo zokusebenza zezindaba zonke ziyadinga ukuchitha ngamaphuzu amaningi. Ukubuyisela i-LNG kusinika isikhungo sokuhlula okuncane esihlukile noma kuphi okudingekayo.

Umbala wokuphakama kwezintemperatura kuyisisekelo. Njengoba i-LNG iphakama kusukela ku-162°C kuze kumkhulu wokuphakama, kungakwazi ukusebenzisa kakhulu kwezinye izinkulungwane zezindlela zokusebenza ngokugxilwe kwezintemperatura ezahlukene. Umphakathi wokuphakama okugcwele—okungaphansi kuka-100°C—uyisisekelo sokwenza isebenza esihlukene ngokugcwele, apho i-oxygen, i-nitrogen, ne-argon zihlanganiswa njengezilithu. Izintemperatura ezingaphakathi ezingu-50°C kuze ku-80°C zingasebenzisa i-organic Rankine cycles ukuthenga amandla noma ukuthuthukisa izindawo zokugcina umbala. Ukuphakama okuphezulu kahle kwe-0°C kusebenza kubhilding yokuqinisa amafutha noma kuzokusebenza kwezindawo zokuphakama kwesikhundla.

Indlela yokwenza ubudlelwane bokuphakama kwezintemperatura kwezindlela zokuvuselela kanye nezidingo zokuphakama kwezindlela zokusebenza emuva kuyo. Izinhlobo zokuhlanganisa amandla kufanele zibonelele ukusebenza kwezinhlobo ezimbili zokusebenza, izinkinga zezintemperatura ezinkulu, nokuthi kungabikho ukuphakama kwezilithu zomoya noma i-CO₂ esikhundleni somoya. Lezi zizinga zokwenza izinto, kodwa ziziqondwa kahle futhi zingasolveka ngokusebenzisa indlela yokwenza eyodwa.

Kuphi Ukuphakama Kusebenza Ngokwempilo

Ukuphulula amagasi kwenziwa ngokwemvelo kuyisibonelo esihle kakhulu sokusebenzisa umoya wokugcina ukuchitha kwe-LNG. Izinkinga zokuchitha kuzimele kahle—izinkampani zokuphulula amagasi zisebenza ngokulinganayo nesikhathi lokuchitha kwe-LNG, lapho i-LNG ichitha inkulu yomoya wakho wokuchitha. Amaphayile ayatholakala ukuthi ukudibanisa umkhondo wokuvula i-LNG nezinkampani zokuphulula amagasi zinokufika ekupheleni kwemisebenzi yokusebenzisa umoya wokuchitha okungaphezu kwe-90% . Ukusebenzisa umoya wokuchitha ngokushesha kwezinhlobo eziqondene kutholakala ngokulinganayo ne-0.022 kWh ngokulinganayo kwekilogram yomoya owususwakalwe—lokhu kubhekana kahle nokusebenzisa izinkampani zokuphulula amagasi ngokwesibini.

Amaphayile ayesi-2024 ayabonisa ukuthi kukhona ukuthandana kakhulu kwezinhlobo zokusebenza. Isibonelo esikhulu sokuphulula amagasi ngokusebenzisa umoya wokuchitha kwe-LNG sasemhlabeni emnye yezinkampani zokuthola i-LNG eNingizimu-Mashariki yaseMelika, nesikhwama sokuproducwa kwezilitha ezingu-660 ngusuku isilayishini sisebenzisa isistimu sokugqibela kwe-LNG ngokuzimisela kumkhombobo wokuhlanza amanzi, sisebenzisa ubukhulu bekugqibela ukufaka amandla okuhlanza kwe-oksijini, i-nitrojini, ne-argon ngaphandle kokusebenzisa izikhululi zokufaka amandla ezingaphandle. Ukuthenga kwale ndawo kubizwa ngamakhulu amabili amashumi amaningi we-RMB, kodwa ukuthenga kwezindlela zokusebenza zokuhlanza kwezindawo zokuhlanza zezindawo zokuhlanza zokusebenza kuyinkimbinkimbi.

Ngaphezu kwezinhlangano zokuhlanza, ukubuyela kwabukhulu kubonakala kusenziwa kwezindawo zokuphatha amandla. Izisitemu zesi-Rankine zokusebenza ngezinye izinkulungwane zokusebenza zinokuguqula ubukhulu obuncane ku-amandla. Isiprojekthi esisodwa sasekutshani sasithola ukuthenga kwamandla angu-26 emillion kWh ngokuphelele kwebukhulu bekwe-LNG kuphela. Ukuthenga kuyiphakathi kwezinkinga zokuthenga kwezindawo zokuphatha amandla nezinkinga zokuthenga kwezindawo zokuphatha amandla, kodwa ngeminye imizuzu, lezi zisitemu ziyathola isiphumo ngeminye imizuzu.

Ukubonakala Kwesikhathi Sokusebenza

Ukuxoxa okuphelele ngokwemvelo kwe-LNG cold recovery kufanele kubonwe izinkinga zokusebenza. Akukho terminal eliqinileyo. Izindlela zokusebenza ziyasebenza kuphela lapho kukhona isicelo esisodwa, esisodwa, sokuchitha ukuchitha—izindawo zokususa amagama (air separation plants) azikwazi ukusebenza ngokuthintana nezilinganiso zokususa amagama kwe-LNG. Iziterminal ezenza umsebenzi wokuphakamisa (peaking facilities), noma zibe yizilinganiso ezihlukahlukene kakhulu zokususa amagama, zibeka izinkinga eziphambili kuzokugxilwa.

Kunezinkinga zezobuchwephesha zokuchitha ukuchitha kakhulu. Ukuchitha kwesikhombisa sokuchitha (heat exchanger fouling), ikakhulu esikhundleni sesinye sesigaba (air side) lapho amanzi angafika futhi ayachitha, kufanele kubhekwe ngokujabulisayo. Ukuphakama kwesifunda sokuchitha (pressure drop) kwenza ukuthi izimpumpu zama-LNG zisebenze kakhulu. Futhi ukugxilwa kwanoma yikuphi kwenza ukuthi umsebenzi weterminal ubaluleke kakhulu—lokhu abasebenzi bakhathazeka ngakho.

Ithabuli elihl above yavimbela ukuguqula okuphundutse. Ukugcina kunceda kakhulu ekusebenzeni kodwa kuyaphila ukuhambisana kwezindawo nokusebenza ngokwesibonelo. Kuma-terminal onamathuba amandla, okanye abasebenzisa amaqhinga amakhulu okanye izimpahla zokusebenza ngokuphelele—kodwa kuma-terminal ophakeme, akukho mlando wokuthi kuyinto enobuchopho.

Isibonelo esifanele ukuzilungiselela

Umsebenzi waseNtshonalanga yase-Asia uyavimbela ubuchopho nobubi. I-terminal elithi yayisebenza ngokuphelele ngokuphakeme kwe-30 million standard cubic feet per day, ibeservisa izimpahla zokusebenza ngokuphelele. Ithimba lokusebenza lalizilungiselela izindlela eziningi zokuvimbela isikhalazo esiphakeme futhi lalifika ekwahlukaneni kwezinye izindlela: isikhalazo esiphakeme kuma-ASU okunye nokuthenga i-liquid oxygen ne-nitrogen, futhi isikhalazo esedlula kuma-district cooling system okuyaservisa izimpahla zokusebenza eziphakeme.

Ukugxilwa kwe-ASU kwenzeka njengoko kwalwakhiwe, kubeka izinto eziluhlaza nezinkulungwane zokuphatha ziyafika eminyakeni yezindustria. Kepha, kubonakala ukuthi kubhekene nezinkinga ezingaphansi kokukhanya kwe-district cooling. Ukuguqula kwesilinganiso sesikhathi sokugcina kwe-LNG kahle kungafani nesilinganiso sokukhanya kwe-district cooling njengoba kwalwakhiwe kuqala. Lokhu kubiza ukuthi kudingeka ukudala i-storage yokuqinisa futhi i-loop yomshini wokuchitha okwesibili ukuze kususekeleke izinkinga. Isifundo esisodwa: ukuvikela ukuchitha kubonakala kahle kwi-diagram yokuchitha, kodwa isidingo sokuhambisana kwezinhlobo zokukhanya nokufaka kuyizinkinga eziningi.

Kule ndawo eya kuyi-industri

Umnyango wokulawula uyaphambana ngokuthuthukisa ukubuyisela kwechiliza. Imithombo yokuvimbela kwe-carbon nokulawula kokusebenza kwezindawo zokusebenza kuzoba yinkimbinkimbi ekubuyiselweni kwemithombo yechiliza nokubuyisela kwechiliza, futhi leyo yizindlela zokuphatha izinhlelo zokusebenza. I-International Energy Agency ibonisa indima yokusebenza kwezinhlelo zokusebenza kuzo zonke izindawo zokusebenza kwe-LNG ukunciphisa ukungena kwe-emissions ngokujulile. Ukubuyisela kwechiliza akakhiphe ngqo i-CO₂ emissions emkhumbini wokusebenza kwezinye izinto, kodwa kususa ukusebenza kwezilivu ezizokusebenza kwe-grid—futhi emazwe amaningi, le-grid power isebenza ngamafuel ayesifazane.

Abasika izinto zokusebenza bavumela ngokuthuthukisa izinto zokusebenza eziphathelene nako. Izinhlelo zokubuyisela kwechiliza eziphathelene nezinhlelo zokusebenza zezinhlelo zokubuyisela kwechiliza nezinhlelo zokulawula ziyatholakala kahle kakhulu, okunciphisa umsebenzi wokulawula kwezinhlelo zokusebenza. Le teknoloji iyaphambana kusuka kwezinhlelo zokulawula ngokwesibonelo kuma-modular, izinhlelo ezinokubuyiselwa.

Indima eyodlula kubalulekile kukhona ukugxilwa kwe-cold recovery ne-carbon capture. Amathuluzi amasha amaningi aqondiswe ngokugcina kwe-energy yelithium natural gas (LNG) nokugcina kwe-Allam cycle—umsebenzi wokuvutha okusebenzisa oksijini kuphela, okuproducisa umkhakha wama-CO₂ owodwa okwenzeka ukuthi kugcinwe ngokuphelele . Umhlaba wokugcina kwe-LNG ukusukela kwe-regasification ungasebenza ekugcineni isilungu sokuvutha u-oksijini futhi ungasebenza ekugcineni ama-CO₂ ngokufakwa kwazo emafutha ukuthi zihambiswe. Izinkundla zokugcina zikhona, kodwa izinhlangano ziyizinga eliphezulu futhi ziyizindawo ezinomthwalo wokuthenga.

Kubantu abasebenzisa ukugcina kwe-cold, indima yokwakha kuyinto yokubala ngokwanele indima yokuthumela, indima yamandla yendawo, nokutholakala kwezinhlangano eziphelele zokuthenga umhlaba wokugcina. Akukho ndawo yonke iyakwazi ukwenza lokhu. Kodwa kubantu abayakwazi ukwenza lokhu, iziphumo zokusebenza neziphumo zokuhleleka kwezwe ziyakwazisa ukuthi kuyinto enobuchopho.

Izinkampani ezifana ne-GreenFir zibhala isibonelo esikhulu sokuthumela izinkampani zokusebenza kwe-cryogenic ozokugcina lezi zindlela zokuhlanganisa. Ngokufana nezinhlobo zezincwadi zase-ASME no-CE futhi nesiqulelo seziprojekthi ezihambisana ngemibhalo yezinye izizwe, ukwakha kwabantu nokukhulula ukuthi kubhekwe kahle kuzokuphatha iziprojekthi zokubuyisela isikhangiso esingaphansi. ukuchaza okunembile kunezinto; umbuzo uyisiphi ukuthi iziprojekthi zokusebenza nezimfundo zokubuyisela kuzokuhlanganisa ukuze zithuthukise ukusetshenziswa kabanzi.