Farko na Cryogenic Distillation da Membrane Separation

Tashin farko a tsarin gas na ala

Cirewa nitrogen daga gas na ala yana da fatin fuskanci har sai ka duba lambobi. Diamita na nitrogen da methane sun faru da wani farko ba tare da 0.2 angstrom, kuma yadda suka ci gaba su ke da farko na 10 daraja a cikin yadda na ala. Wannan farko mai yawa na molekulai yana nufin cirewa ita ce babu da fatin fuskanci, yayin da kowace teknoliji ka yi amfani da su.

Kudin kamar yanzu ya dace. Kuma kamar yanzu, alama na gurbi na gas tana kawo nitrogen zuwa 2-4 mol%, amma wani gas na gurbi yana da 15% ko kafin. Wani kashi da kashi na nitrogen wanda ake kara a gas na bayani yana nufin karamin kariya na kariya da karamin kudin da ke samun. Amma yadda ake kara nitrogen kafin yana karamin energy da karamin kudin na gurbi. Samun karamin karamin da karamin yana nufin karamin kudin da karamin teknik.

Wadannan biyu teknoliji suna kama da karamin karamin: cryogenic distillation da membrane separation. Wadannan biyu suna da abokan da suka yi karamin karamin, amma haqiqi yana da karamin karamin. Zazzagayen da aka zuba shine yana da karamin karamin na composition na gurbi, karamin karamin na flow rate, karamin karamin na product, da karamin karamin na site-specific constraints. Fasahar da wannan teknoliji ta fuskata—da wannan teknoliji ta karamin karamin—yana da karamin karamin don samun karamin karamin na kudin da ke samun.

Yadda Cryogenic Distillation Ta Aiki

Cryogenic distillation yana amfani da farko na ƙarfi na boiling point na methane (-161.5°C) da nitrogen (-195.8°C). Gas na gaba ya dace, ya kawo, da ya ƙare shi a cikin turbo-expanders don samun ƙarfi na yawa wanda ke bukatar partial liquefaction. A cikin column na distillation, vapor na taka yana tsakara da liquid na taka a cikin karamin yadda na theoretical trays ko structured packing. Methane, wanda shine babbar component da yawa na boiling point, yana kuma kama a cikin liquid phase a ƙasa. Nitrogen, wanda shine yawa na volatile, yana taka a sama a cikin vapor.

Ayyan yana ci gaba da energy—ba a iya gudumta da thermodynamics na yanka heat a cryogenic temperatures. Amma shine kuma yawa na effective. Commercial cryogenic nitrogen rejection units suna samun methane recoveries da yawa a cikin 98% da suke iya gudumta nitrogen content don pipeline specifications na 2-3 mol% ko kamarun. Technology suna rarrabe da yawa daga modest flow rates zuwa massive baseload LNG plants.

Wani abu da ke ƙasa ta hanyar fahimtar shine kuma yadda za a iya saita shi. Za a iya saita Cryogenic NRUs da NGL recovery a cikin wani cold box daya, kuma su share refrigeration da compression systems. Wannan kuma yadda ya zai taimaka wajen yadda za a iya samun karamin bayani da kuma yadda za a iya rage gida ta hanyar yadda ba a iya saita su a cikin wani processing train daya. Don masu amfani da gas composition mai tsoro da kuma wani karamin product streams, wannan kuma yadda na saita shine mai mahimmanci.

Samar da Gas ta hanyar Membrane: Wani Hanyar Misa

Samar da gas ta hanyar membrane ya ɗoƙa daga hanyar muna yiwu. Bayan yadda za a kuma gas don yadda za a iya samun cryogenic temperatures, membranes suna amfani da differential permeability—wani gas molecules suna tattara a cikin membrane material ta hanyar farko. Nitrogen ya tattara ta farko da methane, don haka permeate stream ta zama nitrogen-enriched kuma retentate stream ta zama methane-enriched.

Wasu abu ne da aka sauke. Ba shi da cold box, ba shi da turbo-expanders, ba shi da distillation trays na musamman. Sistemu na membrane suna aiki ga wani yadda mai ƙarfi ko wani yadda mai ƙarfi kusa da yadda na gida, da kuma karami na makinan da suka tsara, da karami na piping na cryogenic. Wannan saukarwa ta nufin yadda mai ƙarfi na kudin sabon abu don abubuwan da suka dace da karami da karami, da kuma yadda mai ƙarfi na samun abu.

Amma yana da wani batu. Selectivity na membrane ga nitrogen don methane yana da karami. Wani daga cikin membrane na bazzar mai kyau suna samun separation factors na 3 zuwa 5 kawai, don haka yana da karami da selectivity na distillation. Wannan karami yana nufin cewa membrane suna gaskiya don gyara nitrogen don 3 zuwa 5 mol%, da kuma loss na methane a permeate stream zai iya taka amma. Kowace molecule na methane wanda ta fito a cikin membrane ta nufin loss na abu da kuma gyara na income.

Yadda ake buƙatar kuskuren ya zai ƙara yadda ake bayarwa. Kullumun suka yi ayyukan da ke cikin ƙananan farama wanda ke ƙare ta hanyar kullumun, wanda ke nufin kuskuren da gas na gaba ko gas na ƙarfi. Wadannan kuskurun suka ci gaba da kwamfutawa kuma suka buƙata ayyukan gudummawar, wanda ke ƙara kadan daga yadda ake so da kullumun.

Kuɗi da Kuɗi: Ayyukan da Yadda ake bayarwa

Farko na ayyukan da suka bayani a kan wannan ƙungiya ya zama baya lokacin da ku ka duba su ne da ne da kuma a cikin hanyar da ke da kuma da kuma.

Alama suka nuna shi ne. Cryogenic distillation ta faruwa a cikin abubuwa da yawa, da alama na fuskanci da yawa, kuma a cikin abubuwan da ke bukata da fuskanci na methane. Membrane separation ta faruwa a cikin abubuwan da ke bukata da fuskanci na nitrogen a cikin 15 mol% kuma a cikin abubuwan da ke bukata da fuskanci da yawa.

A 2025, a sanya gaskiya akan teknolohiya na fuskanci, cryogenic distillation ta faruwa a cikin abubuwan da ke bukata da fuskanci na nitrogen saboda ya iya haɗa abubuwan da yawa kuma ya iya fuskanci da yawa. Wannan ba shi nufin waɗanda membrane sun kashe—sun da fuskanci a cikin abubuwan da ke bukata da fuskanci. Amma yadda abubuwan da ke bukata da fuskanci kuma yadda abubuwan da ke bukata da fuskanci na midstream gas processing sun haɗa cryogenic.

Idan Ana Kuma Amince Ga Wani Zane

Kamar yadda ake gano, kuma idan yadda cryogenic distillation ta dace da alama, membrane separation ta sanya wani tsari na sarrafa. Misali na biyu shine biogas upgrading na karami. Biogas daga landfill ko digesters yana da 40-60% methane da 30-50% CO2, kuma nitrogen yana da karami ne kamar 5%. Membranes suna iya yin CO2 removal da kyau, kuma nitrogen yana da karami ne kamar yadda zai iya samun karami na sarrafa.

Misali na uku shine pretreatment a cikin cryogenic systems. Wani membrane stage zai iya yin bulk nitrogen removal daga high-nitrogen feed a cikin gas din da za a shiga cryogenic unit, yana nufi load daga distillation column kuma zai iya save energy. Hybrid membrane-cryogenic configurations suna amsa da kira da kira, kuma wani design ya samu 93% recovery a energy consumption wanda ke da alama da standalone cryogenic performance. Iyaka na hybrid wadannan yana dace da operational flexibility ba da direct energy savings ba.

Wuraren da ke nesa ko kuma a bakin teku ma suna son membranes a wasu lokuta. Ƙarin kayan aiki da kuma ƙananan nauyi suna da muhimmanci a lokacin da ake bukatar masu kula da kayayyaki da kuma ƙwararrun ma'aikata. Amma ko da a cikin waɗannan mahallin, dole ne a tantance hukuncin asarar methane a hankalirasa 5-10% na samfurin methane zuwa rafin da ke shiga cikin sauri na iya share duk wata fa'ida ta farashin jari.

Zaɓin da Ya Dace - Zaɓin Fasaha da ta Dace

Wani mai sarrafa gas a cikin shale na Eagle Ford ya fuskanci wannan ƙalubalen zaɓin fasaha. Abincin su ya ƙunshi 12% nitrogen, tare da ƙimar ruwa a kusa da 80 MMSCFD. Gidan bututun yana buƙatar 3% nitrogen a cikin gas ɗin tallace-tallace. Shawarwarin membrane na farko sun yi alkawarin rage farashin jari da saurin shigarwa, amma cikakken bincike ya nuna matsala.

Sistayin fayil ya zama da karamin 6% na metan da ke cikin shakara ta hanyar shakara na gaba. A yadda ake bayar da gas akwai, wannan yana nufin duka $2 juta a cikin shekara. Iyayen cryogenic distillation suna da karamin sarakin kuma karamin samun metan da ke cikin 98%, wanda ya sa karamin dukkanin metan da ke cikin shakara. Zamanin da aka yi amfani da cryogenic technology ya kashe karamin 18 mizan.

Matakin shakara ya zauna a cryogenic distillation. Shakaran ya gudan cikin 3 shekara da karamin yadda ya iya gudan da ke cikin 97%, kuma ya gudan da karamin yadda da ke cikin shakara na pipeline. Aboki na fayil ba su da takaici a yadda suka bayani a kan abubuwan da suka iya gudan cikin—suna da karamin yadda da suka iya gudan cikin kamar yadda suka iya gudan cikin karamin yadda da ke cikin cryogenic distillation wanda ya sa su ya zama abin da ke cikin shakara na yadda da ke cikin wannan shakara.

Karamin yadda da ke cikin zaunin teknoliji

Fasahar da cryogenic distillation da membrane separation ba tana nufin ina yin fassara wani abu ne “ba daidai” a wani ma’ana ta yawa. Yana nufin wani abu ne ya zama mai kyau don yin amfani da shi a cikin wani al’ada. Idan kuma nitrogen yana da karami, da kuma bukatar da purity mai kyau, da kuma methane na iya amincewa, zai nufin cryogenic distillation. Idan nitrogen yana da karami kura, da kuma bukatar da purity mai karami, da kuma idan a iya gudun mata da methane, zai nufin membranes.

Ayyukan masu amfani sun samu kadan shekara na amfani da biyu na teknolijin, cryogenic distillation yana da karami a rashin tsoro da karami a yadda yake amincewa a kwarai. Membranes suna da karami a rashin tsoro da karami a yadda yake amincewa a kwarai, amma suna da karami a gudun mata da methane wanda ke iya yin karami a yadda yake amincewa. Wani analisis mai kyau na teknoliji da ekonomi, wanda ya kashe a cikin hali na feed da karamin abubuwa, shine kamar yadda ke amincewa a yadda yake amincewa.

Shirkoki kamar GreenFir muna da kadan shekara na amfani da fasahar biyu na sistem, da kuma karami a cryogenic distillation equipment wanda aka sanya a ASME standards wannan karamin biyu ya kasance muna da mahimmanci saboda yana nufin cewa tallafin teknoliji zai iya aikata da al'adu na kayan aiki ba tare da wani abu ne da ke cika shi kamar yadda wani masu sanya suna buƙata.