Ukuqonda Imishini Yokuhlanza Embonini Yamakhemikhali
Ukucwilisa kungenye yezindlela ezibaluleke kakhulu zokusebenza kweyunithi embonini yamakhemikhali. Kusukela ekuhlanzweni kwe-solvent elabhorethri kuya ekuhlukanisweni kwezingxenyana ze-petroleum esikalini sokuhlanza, ukucwilisa kwakha umgogodla wezinqubo eziningi zokukhiqiza. Imishini yokucwilisa—kungakhathaliseki ukuthi amayunithi alula noma amakholomu amakhulu okucwilisa—ihlukanisa izingxube ngokusekelwe ekungafani kokuguquguquka (ukukhululeka kokuhwamuka) kwezingxenye zazo. Lesi sihloko sixoxa ngemiqondo eyisisekelo, izingxenye eziyinhloko, izinhlobo zokucwilisa, imingcele yokusebenza, kanye nezinselele nezici zokuphepha zokusebenza kohlelo lokucwilisa.
Izimiso Eziyisisekelo Zokuhluza
Empeleni, ukucwiliswa kusebenzisa iqiniso lokuthi into ngayinye inephuzu lokubila elihlukile kanye nomfutho womusi. Uma ingxube ishiswa, izingxenye ezishintshashintshayo zizoya esigabeni somusi. Lomusi ube usupholiswa ku-condenser uze ubuyele kuketshezi (distillate). Okwamanje, uketshezi olusele esitsheni sokushisa noma phansi kwekholomu luvame ukuba nezingxenye eziningi ezinamaphuzu aphezulu okubila.
Kodwa-ke, kubalulekile ukuqonda ukuthi ukucwilisa akukhona nje "ukushisa nokupholisa." Ngengxube ethile, kukhona ukulingana komswakama-uketshezi (VLE), okunquma ukwakheka komhwamuko noketshezi ekushiseni nasekucindezelweni okunikeziwe. Kukholomu yokucwilisa, izinqubo zokuhwamuka kanye nokufiphala zenzeka ngokuphindaphindiwe ezigabeni ezahlukene, okuholela ekuhlukanisweni okubukhali kakhulu kunasekucwilisweni okukodwa.
Izingxenye Eziyinhloko Zomshini/Iyunithi Yokucwilisa
Embonini, “umshini wokucwilisa” uvame ukubhekisela ephaketheni lemishini esebenza njengohlelo. Izingxenye zayo eziyinhloko zifaka:
1. I-Reboiler (isifudumezi sekholomu engezansi)
I-reboiler inikeza ukushisa ukuze kushiswe uketshezi olungaphansi kwekholomu. Umhwamuko ophumelayo ukhuphukela phezulu kwekholomu futhi usebenze njenge-"injini" yokuhlukanisa. Izinhlobo ezivamile zama-reboiler zifaka phakathi ama-kettle reboiler, ama-thermosiphon reboiler, kanye nama-forced circulation reboiler.
2. Ikholomu yokuhluza
Ikholomu iyithuluzi eliyinhloko lokuhlukanisa. Iqukethe idivayisi yokuxhumana yomhwamuko noketshezi ngesimo sethreyi (isihlungi/ipuleti) noma ukupakisha. Umgomo ukudala indawo enkulu yokuxhumana ukuze umhwamuko noketshezi kufinyelele kancane kancane ekubaleni.
3. Ithreyi noma Ukupakisha
– Amathreyi (isib. amathreyi esihlungo, amathreyi evalvu, izivalo zamabhamuza) afanelekela ububanzi bokusebenza futhi kulula ukuwaqapha, kodwa ngokuvamile anokwehla okukhulu kwengcindezi.
– Ukupakisha (okungahleliwe noma okuhlelekile) kuvame ukukhethwa ukuze kusetshenziswe i-vacuum distillation noma izinhlelo ezizwela ukwehla kwengcindezi, ngoba ukwehla kwengcindezi kuphansi.
4. I-Condenser
I-condenser ipholisa umusi kusukela phezulu kwekholomu uye kuketshezi. Kungaba i-condenser ephelele (efingqa wonke umusi) noma i-condenser engaphelele (ekhiqiza ingxube ye-vapor-liquid).
5. I-Reflux drum kanye nesistimu ye-reflux
I-distillate evela ku-condenser iyaqoqwa, bese kuthi enye yayo ibuye ibuyele phezulu kwekholomu njenge-reflux. I-Reflux ibalulekile ngoba ithuthukisa ubumsulwa bomkhiqizo ophezulu ngokugeza umhwamuko okhuphukayo ngoketshezi oluhlayo.
6. Amaphampu, amapayipi, izilawuli zezinsimbi
Izinhlelo zokuhluza zithembele ekulawuleni izinga lokugeleza, izinga lokushisa, ingcindezi, kanye nezinga loketshezi. Ukulawula okuzinzile kunquma ikhwalithi yomkhiqizo kanye nokusebenza kahle kwamandla.
Izinhlobo ze-Distillation embonini yamakhemikhali
Kwakhiwa izinhlobo ezahlukene zokuhluzwa ukuze kubhekwe izici ezahlukene zezingxube:
1. Ukuhluzwa okulula
Ngokuvamile uma kukhulunywa ngomehluko omkhulu wamaphuzu okubila noma ukuhlukaniswa okuqinile. Ngokuvamile uma kukhulunywa ngezinga elincane.
2. Ukuhluzwa kwezingxenye
Ukusebenzisa amakholomu anezigaba eziningi zokuhlukanisa. Lolu uhlobo oluvame kakhulu embonini, isibonelo, ukuhlukaniswa kwe-benzene-toluene noma ukuhlukaniswa kwe-hydrocarbon.
3. Ukuhluzwa kwe-vacuum
Ukwehlisa ingcindezi yokusebenza ukuze wehlise iphuzu lokubila kufaneleka kuma-compounds anamaphuzu aphezulu okubila noma lawo abola kalula emazingeni okushisa aphezulu. Izibonelo: izingxenyana ze-petroleum ezisindayo, ukucwenga ama-monomer athile.
4. Ukuhluzwa ngomusi
Umhwamuko wamanzi ufakwa ukuze kusizwe ukuhwamuka kwezingxenye eziphilayo emazingeni okushisa aphansi. Usetshenziswa kabanzi emafutheni abalulekile kanye nakwezinye izinqubo zokubuyisa izinyibilikisi.
5. Ukuhluzwa kwe-Azeotropic / extractive
Ngezingxube ezakha i-azeotropes (ukwakheka komhwamuko kulingana nokwakheka koketshezi), ukucwiliswa okuvamile kunzima ukufeza ubumsulwa obuphezulu. Isixazululo: ukwengeza i-entrainer (i-azeotrope) noma i-solvent ekhethiwe (ekhipha) ukushintsha ukuguquguquka okuhlobene. Isibonelo esivamile: ukuhlanzwa kwe-ethanol kusuka engxubeni yamanzi ne-ethanol.
Amapharamitha Okusebenza Abalulekile
Ukuze umshini wokuhluza usebenze kahle, opharetha kanye nonjiniyela bagxila kumapharamitha amaningana:
– Ukucindezela kwekholomu: Kuthinta iphuzu lokubila kanye ne-VLE. Ukucindezela okuphezulu kwandisa izinga lokushisa lokusebenza; ukucindezela okuphansi kusiza ama-compounds azwela ukushisa.
– Isilinganiso se-Reflux: Uma i-reflux iphezulu, ngokuvamile ubumsulwa buyanda, kodwa ukusetshenziswa kwamandla nakho kuyanda.
– Izinga lokubilisa/umsebenzi wokubuyisela kabusha: Kunquma inani lomusi okhuphukayo; okuphansi kakhulu kuholela ekuhlukaniseni okubi, okuphezulu kakhulu kungabangela izikhukhula.
– Inani lezigaba ezisekelwe kumbono kanye nokusebenza kahle kwethileyi/ukupakisha: Umqondo wezigaba ezisekelwe kumbono usiza ukuklama. Ukusebenza kahle kwangempela kuthonywa yi-hydrodynamics kanye nezakhiwo zomzimba zengxube.
– Izimo zokudla (izinga lokushisa, isigaba, ukwakheka, izinga): Izimo zokudla zithinta iphrofayili yokushisa kanye nomthwalo wekholomu. Ama-heater noma ama-flash drum avame ukusetshenziswa ukulungisa ukudla.
Izinkinga Ezivamile Zokuhlinzwa
Ekusebenzeni kwangempela, amakholomu okuhluza angabhekana nezinkinga ezilandelayo:
– Ukukhukhula: Ukugeleza komusi kuphezulu kakhulu kangangokuthi uketshezi luba nobunzima bokwehla; okubangela ukwehla kwengcindezi, okunciphisa ikhwalithi yomkhiqizo.
– Ukukhala/ukulahla: Umusi uphansi kakhulu kangangokuthi uketshezi lungena ngethreyi; ukuthintana komswakama nomhwamuko kuyawohloka.
– Ukugqwala: Igwebu landisa ukugeleza (ukunyakaza koketshezi phezulu), kunciphisa ubumsulwa.
– Ukufakwa: Amaconsi amanzi athwalwa ngumhwamuko aya phezulu; angangcolisa i-distillate.
– Ukungcola/isikali: Amadiphozithi anciphisa ukudluliselwa kokushisa ku-reboiler/condenser futhi avale ukupakisha/ithreyi.
Ukubhekana nalezi zinkinga ngokuvamile kuhilela ukulungisa umsebenzi we-reboiler, i-reflux, ingcindezi, noma ukulungiswa njalo (ukuhlanza nokuhlolwa kwangaphakathi).
Ukusebenza Kahle Kwamandla Nokuhlanganiswa Kokushisa
Ukucwilisa kwaziwa njengenqubo edinga amandla amaningi ngenxa yenani elikhulu lokushisa kanye nokujiya okudingekayo. Imboni yanamuhla ifuna ukwandisa ukusebenza kahle ngokuthi:
– Ukuhlanganiswa kokushisa: Ukusebenzisa ukushisa okuvela kwezinye izindlela zokucubungula ukuze kufudunyezwe ukudla.
– Ukuhluzwa kwepompo yokushisa enemiphumela eminingi kanye ne-heat pump: Ukusebenzisa ukucindezela komphunga noma ukulawulwa kwengcindezi "ukuphinda usebenzise" ukushisa kokufinyela.
– Ukuthuthukisa ukulawula: Ukulawula Inqubo Ethuthukisiwe (i-APC) kusiza ukugcina imisebenzi iseduze nephuzu elihle ngaphandle kokwehlisa ikhwalithi.
Le mizamo yokusebenza kahle ibalulekile, ngoba izindleko zamandla zivame ukuba yingxenye eyinhloko yezindleko zokusebenza kweyunithi yokuhluza.
Izici Zokuphepha Nezemvelo
Imishini yokuhlanza isebenza ngaphansi kwamazinga okushisa aphezulu kanye nokucindezela, futhi ivame ukuphatha izinto ezivuthayo, ezinobuthi, noma ezigqwalisayo. Ngakho-ke, ukuphepha kumele kube yinto eza kuqala:
– Ukuvikelwa kwengcindezi: I-valve yokusiza kanye nohlelo lokuvutha ukuze kuvinjelwe ukucindezeleka ngokweqile.
– Ukulawula ukuvuza: Ukuvala amaphampu, ama-flange, kanye nezinhlelo zokuthola igesi.
– Izinto zokwakha: Ukukhethwa kwezinto ezingagqwali (isb. insimbi engagqwali, ama-alloy akhethekile) ngokwezakhiwo zamakhemikhali.
– Ukukhishwa kwegesi kanye nemfucuza: Ukulawulwa kwe-VOC (ama-volatile organic compounds), ukwelashwa kwe-condensate, kanye nokuvimbela ukukhishwa kwezinto eziyingozi.
Ukuhambisana nezindinganiso (isib. i-API/ASME) kanye nokusetshenziswa kwe-HAZOP kanye nezinqubo zokusebenza eziqinile kusiza kakhulu ukuvimbela izehlakalo.
I-Penutup
Ukuqonda imishini yokuhluza embonini yamakhemikhali kusho ukuqonda ukusebenzisana phakathi kwe-thermodynamics, ukudluliselwa kwesisindo, ukudluliselwa kokushisa, ukwakheka kwemishini, kanye namasu okulawula. Ukuhluza kungaphezu nje kwedivayisi yokuhlukanisa, kodwa kunalokho uhlelo oluhlanganisiwe olunquma ikhwalithi yomkhiqizo, ukusetshenziswa kwamandla, kanye nokuphepha kwenqubo. Ngokukhetha indlela efanele yokuhluza, ukwakheka kwekholomu efanele, kanye nokusebenza okulawulwayo nokusebenza kahle, imboni ingakhiqiza imikhiqizo yamakhemikhali emsulwa kakhulu ngokonga nangokuphepha.
Uma ufisa, ngingaguqula lesi sihloko sibe sezobuchwepheshe kakhulu (ngezibonelo zokubala isilinganiso se-reflux, izigaba zethiyori, noma i-McCabe–Thiele) noma sithandwe kakhulu ngumfundi ojwayelekile.
