Ukuqonda Ukulinganiswa koXinaniso loLwawo kwi-Polymerization Reactors
Ulwelo oluchanekileyo lokulinganisa uxinano lubalulekile kulawulo lwenkqubo yeekhemikhali kwi-reactors ze-polyethylene polymerization. Kwiinkqubo ze-polyethylene polymerization, uxinano lusebenza njengophawu oluthe ngqo lokwahlulwa kwe-polymer, ubukrelekrele, kunye nokusasazwa kobunzima be-molecular, nto leyo echaza iipropati ezibalulekileyo zezinto ezifana nokuqina, ukumelana nempembelelo, kunye nokukwazi ukuqhubekeka. Umzekelo, i-polyethylene ephantsi koxinano (LDPE) ifuna ulawulo oluqinileyo phezu kwamasebe amade, ngelixa i-polyethylene ephezulu yoxinano (HDPE) ibonakaliswa ngamasebe amancinci; zombini zixhomekeke ekuchanekeni kokufundwa koxinano lolwelo ukuze zikhokele iimeko zokusabela ekusebenzeni okujoliswe kuko.
Ngexesha le-polyethylene polymerization reaction, umlinganiselo wobuninzi bolwelo ngexesha langempela uvumela abaqhubi beenkqubo ukuba balungise ubushushu, uxinzelelo, kunye namazinga okutya kwe-monomer, bagcine iimeko ezifanelekileyo zokuphendula kunye nomgangatho wemveliso ohambelanayo. Ubuninzi buyiparameter ehamba phambili yokwahlula amanqanaba e-polyethylene (LDPE, HDPE, LLDPE) kunye nokuqinisekisa ukufana kwebhetshi kuyo yonke inkqubo yokuvelisa i-polyethylene. Ukulandelela ubuninzi obuthembekileyo ngeemitha zobuninzi ezikwi-inline ezifana nezo zenziwe yiLonnmeter akuxhasi nje kuphela ukuqinisekiswa komgangatho kodwa kunciphisa ukwahluka kwemveliso kwaye kuphucula isivuno.
Umzobo weMveliso yePolyethylene yoShishino
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Iziseko zePolyethylene Polymerization Reactors
Uyilo lweeReactor eziphambili zeMveliso yePolyethylene
Ii-reactors zebhedi ezinyibilikisiweyo (ii-FBR) zibalulekile kwinkqubo ye-polyethylene polymerization, ingakumbi kwimveliso ye-LLDPE kunye ne-HDPE yesigaba segesi. Ezi reactors zixhoma amasuntswana e-polymer kumsinga onyukayo wegesi, zenze ibhedi eguquguqukayo enokusasazwa kwamasuntswana afanayo. Ulawulo lobushushu olufanelekileyo luyinzuzo ebalaseleyo; ukusebenzisana okuqhubekayo phakathi kwezinto eziqinileyo kunye negesi kukhuthaza ukususwa ngokukhawuleza kobushushu bokusabela, kunciphisa umngcipheko weendawo ezishushu kunye ne-polymerization ebalekayo. Nangona kunjalo, kuvela imingeni yolawulo, ngakumbi ukuguquguquka kobushushu okwethutyana okunxulunyaniswa ne-catalyst dosing okanye utshintsho kumazinga okutya okupholileyo. Iinkqubo zolawulo ze-PID eziphambili zisetyenziselwa ukucinezela oku kuguquguquka kunye nokugcina uzinzo lokusebenza, zixhasa umgangatho we-polymer oqhubekayo kunye nokusebenza okukhuselekileyo kwe-reactor. Iimodeli zeBalance Population (PBM) ezidityaniswe ne-Computational Fluid Dynamics (CFD) zibonelela ngendlela ephucukileyo yokulinganisa kunye nokwenza ngcono i-particle dynamics kunye ne-hydrodynamics, ziququzelela ukwandiswa kunye nokulungiswa kweempawu zemveliso.
Ii-reactors zoxinzelelo oluphezulu zingumqolo we-LDPE synthesis, ezisebenza kwiingcinezelo ezidla ngokudlula ii-2000 bar. I-Radical polymerization kwezi meko ifuna ulawulo olugqithisileyo malunga nexesha lokuxutywa kunye nexesha lokuhlala. Ukuxuba okusebenzayo kuthintela ukwakheka kweendawo ezishushu zasekuhlaleni ezinokuphazamisa ukuhambelana kunye nokhuseleko lwemveliso. Ixesha lokuhlala lilawula ubude betyathanga le-polymer—amaxesha amafutshane athanda ubunzima obuphantsi beemolekyuli, ngelixa ukuhlala ixesha elide kuxhasa ubunzima beemolekyuli eziphezulu. Izifundo ezisebenzisa i-orthogonal collocation kunye neendlela ze-finite element zibonisa ukuba amazinga okutya okuqala kunye namaqondo obushushu ejakethi abalulekile ekwandiseni ukuguqulwa kwe-ethylene kunye nokuqinisekisa ukuba iithagethi ze-melt flow index ziyafezekiswa. Ukuxuba okubi kunokukhokelela ekusasazweni kobunzima beemolekyuli ngokungacwangciswanga kunye nokwanda kokungcola, okusongela ukhuseleko kunye nokufana kwemveliso.
IiMultizone Circulating Reactors (MZCRs) zibonisa indlela yokulawula i-polyethylene polymerization reaction. Ezi ziyila i-polymerization yahlulahlula kwiindawo ezininzi ezidibeneyo kunye nokuhamba okuhlengahlengiswayo, ubushushu, kunye nokungeniswa kwe-ethylene. Iindlela zokupholisa zangaphakathi—ingakumbi kwiindawo eziphakamisayo—zinciphisa kakhulu ukuguquguquka kobushushu, ziphucula ukufana kobushushu ukusuka ekujikeni ukuya kwi-8°C ukuya kwi-4°C. Le ndawo ilungiswe kakuhle yenza amazinga okuguqulwa kwe-ethylene aphucuke ngaphezu kwe-7%, kwaye ixhasa ulawulo oluqinileyo lokusasazwa kobunzima be-molecular. Iipropati zamasuntswana zihambelana ngakumbi ngenxa yokudibanisa isantya segesi kunye nokujikeleza okuqinileyo phakathi kweendawo. IiMZCR zikwabonelela ngamaqonga anokukhuliswa, okwenza kube lula ukutshintsha ukusuka kwimveliso yelabhoratri ukuya kwi-pilot nakwimizi-mveliso ngelixa kugcinwa ukuhambelana kwenkqubo kunye nemveliso.
Impembelelo yeeNguqu zeNkqubo
Ubushushu yiparameter ephambili echaphazela amazinga okusabela kwe-polyethylene polymerization, ubunzima be-molecular, kunye ne-crystallinity. Ubushushu obuphezulu buyandisa ukudluliselwa kwe-chain kunye ne-termination frequency, okukhokelela ekunciphiseni ubunzima be-molecular. Ubushushu obuphantsi bukhuthaza ukwakheka kwe-polymer chains ezinde kodwa bunokunciphisa amazinga okuguqulwa. I-Catalyst dosing inefuthe kumsebenzi kunye ne-polymer chain nucleation. Uxinzelelo oluphezulu lwe-catalyst lukhawulezisa i-polymerization kodwa lunokunciphisa okanye lwandise ukusasazwa kobunzima be-molecular, kuxhomekeke kwi-catalyst chemistry kunye noyilo lwe-reactor. I-Optimized dosing iqinisekisa iipropati ze-polymer ezinqwenelekayo ngaphandle kokufakwa okugqithisileyo okanye iziphene zesakhiwo.
Ukuxuba ngaphakathi kwe-polymerization reactor kuhambelana ngokuthe ngqo nokufana kwemveliso. Ukuxuba okungafanelekanga kungenisa utshintsho lwesithuba kuxinzelelo olukhulu kunye nobushushu, okubangela ukusasazwa kobunzima beemolekyuli ezibanzi okanye ezininzi. Izifundo ze-CFD ziqinisekisa ukuba iipatheni zokujikeleza ezilungisiweyo kunye nokulinganisela kwexesha lokuhlala zinokucinezela i-kinetic extremes engafunekiyo, zivelise i-polyethylene enokulungiswa okucwangcisiweyo kunye nokusebenza koomatshini. Kwiinkqubo ze-MZCR, iiparameter zone zokudibanisa zilawula ngakumbi ukuxuba kunye nobushushu, ziphucula ukuguqulwa kwe-ethylene ye-single-pass kunye nokunciphisa izinto ezingasebenziyo.
Unxibelelwano phakathi koyilo lwe-polymerization reactor kunye neempawu zemveliso luthe ngqo kwaye lunokulinganiswa. Ii-FBR zivelisa amanqanaba e-polyethylene afanelekileyo kwifilimu nakwi-rotational molding, zizuza kwi-small melt flow indices kunye nolawulo oluqinileyo lobunzima be-molecular. Ii-reactors zoxinzelelo oluphezulu ze-LDPE zibonelela ngezakhiwo ezahlukeneyo ze-chain ezikhethwayo kwizicelo ze-extrusion kunye ne-packaging. Uyilo lwe-Multizone lubonelela ngokuguquguquka ekujoliseni iiprofayili zobunzima be-molecular ezintsonkothileyo, zixhasa amanqanaba akhethekileyo. Iindlela zokulinganisa uxinano oluphambili, kubandakanya iimitha zoxinano oluphakathi ezivela kwi-Lonnmeter, zixhasa ulawulo lomgangatho wexesha langempela ngokuvumela ukujonga ngokuchanekileyo uxinano lwenkqubo kunye noxinano lwe-polymer, kubalulekile ukuqinisekisa ukuthotyelwa kweenkcukacha kuyo yonke inkqubo yemveliso ye-polyethylene.
Iindlela zokulinganisa ubuninzi bolwelo kwiindawo ze-Reactor
Imigaqo Ebangela Ukulinganiswa Koxinano
Uxinano luchazwa njengobunzima ngeyunithi yomthamo wento. Kwimeko yee-reactors ze-polyethylene polymerization, umlinganiselo woxinano ngexesha langempela ubalulekile, njengoko unxulumene ngokuthe ngqo ne-polymer crystallinity kunye neempawu zoomatshini, nto leyo echaphazela ulawulo lwenkqubo kunye nomgangatho wemveliso. Umzekelo, ukubeka esweni uxinano kuvumela iinjineli ukuba zibone utshintsho kwi-polymerization kinetics, enokubonisa utshintsho ekusebenzeni kwe-catalyst okanye amazinga okutya kwe-monomer.
Izinto zomzimba nezekhemikhali zichaphazela uxinano kwiindawo zeereactor. Ukunyuka kobushushu kubangela ukwanda kunye noxinano oluphantsi lolwelo, ngelixa uxinzelelo oluphezulu ludla ngokucinezela ulwelo kwaye lunyuse uxinano lwalo. Kwireactors zepolymerization, utshintsho lwesakhiwo (njengoxinano lwe-monomer, iigesi ezinyibilikisiweyo, izongezo, okanye iimveliso ezilandelanayo) zenza kube nzima ngakumbi ukulinganisa, okwenza kube yimfuneko ukuqwalasela zonke izinto eziguquguqukayo kwinkqubo yokubeka esweni uxinano oluchanekileyo. Kwiimpendulo ezahlukeneyo, ezifana ne-slurry okanye i-suspension polymerization, ukulayisha kwamasuntswana, i-agglomeration, kunye nokwakheka kwamaqamza kunokuchaphazela kakhulu ukufundwa koxinano olubonakalayo.
Iindlela Ezimiselweyo Zokulinganisa Uxinano Lolwelo
Iindlela zokulinganisa ngokuthe ngqo ziquka ii-hydrometer, ii-digital density meters, kunye nee-vibrating-tube sensors. Ii-Hydrometers zibonelela ngokusebenza okulula ngesandla kodwa azinazo iindlela zokuchaneka kunye nokuzisebenzela ezifunekayo kwiinkqubo ze-polymerization ezinoxinzelelo oluphezulu. Ii-digital density meters zibonelela ngokuchaneka okuphuculweyo kwaye zinokudibanisa imbuyekezo yobushushu, nto leyo ezenza zifaneleke ukulinganiswa kwelebhu kunye nolawulo oluqhelekileyo. Ii-vibrating-tube density meters, umnikelo oyintloko ovela kwiLonnmeter, zisebenza ngokulinganisa utshintsho lwe-oscillation frequency njengoko ulwelo luzalisa ityhubhu eyenziwe ngokuchanekileyo. Olu tshintsho luhambelana ngokuthe ngqo noxinano lolwelo, kunye neemodeli zokulinganisa ezibangela uxinzelelo kunye nokuxhomekeka kobushushu.
Iindlela eziphambili nezingathanga ngqo ziyathandwa xa kusetyenzwa i-reactor ezenzekelayo rhoqo. Ii-Ultrasonic sensors zisebenzisa amaza esandi asebenzisa i-high-frequency, zivumela ukulinganiswa koxinano ngexesha langempela nokuba kubushushu obuphezulu kunye noxinzelelo, kwaye zimelana nokungcoliswa kwiindawo zeekhemikhali. Ii-nuclear-based sensors zisebenzisa imigaqo yokufunxwa kwemisebe, efanelekileyo kwi-opaque process streams kunye nokufakwa kwe-reactor kwiqondo lobushushu eliphezulu, ngakumbi apho kukho khona i-gamma okanye i-neutron fields. Ii-microwave sensors zilinganisa utshintsho lwepropathi ye-dielectric ehambelana noxinano lolwelo, oluxabisekileyo kwi-solvent-rich okanye kwi-multiphase streams ezithile.
Iinkqubo zokulinganisa ezikwi-intanethi nezikwindawo enzima kwiimeko ezinzima kufuneka zimelane neemeko ezigqithisileyo zenkqubo—ezifana nee-loops ze-slurry ezixineneyo okanye ii-reactors ze-gas-phase kwinkqubo yokuvelisa i-polyethylene. Ii-densimeters ze-vibrating-tube zibonelela ngemilinganiselo emincinci yesampulu kunye nokusebenza okuqinileyo kubushushu obubanzi kunye noxinzelelo. Ngokwahlukileyo koko, ii-sensors ze-ultrasonic kunye nezenyukliya zigqwesile ekumelaneni nohlaselo lweekhemikhali, ukungcola, kunye nemitha, ngelixa zigcina ukuthembeka kwesignali. Ii-sensors zexesha langempela ezifakwe ngqo ngaphakathi kwee-reactor loops zivumela ukulungiswa kwenkqubo eguquguqukayo ukugcina iithagethi zoxinano olufanelekileyo, ukunciphisa imveliso engakhange ichazwe kwaye kunciphisa ukuxhomekeka kuhlalutyo lwelebhu oluqhubekayo.
Ukujongana nobunzima beenkqubo zeendaba
Izixhobo ze-reactor ezintsonkothileyo ezifana ne-slurry ezahlukeneyo, i-emulsions, okanye i-reaction suspensions zibangela ubunzima obukhulu ekulinganisweni koxinano lolwelo. Uxinzelelo lwezinto eziqinileyo, amaqamza egesi, kunye namaconsi e-emulsion zinokuphazamisa ukufundwa ngokutshintsha ukudluliselwa kobunzima okusebenzayo kunye ne-hydrodynamics. Uyilo lwe-probe kufuneka luvumelane nokuhlaliswa kwamasuntswana kunye neziphumo ze-local clustering, ezifuna ulawulo lokuhamba kolwelo ukunciphisa izinto zokulinganisa uxinano. Umzekelo, kwi-polyethylene polymerization reactors ezisebenzisa i-slurry-phase operation, ukusasazwa kobungakanani bamasuntswana kunye neegesi ezongezelelweyo ezingenayo i-inert zijongene nokuhambelana komlinganiselo woxinano.
Imbuyekezo echanekileyo yobushushu, uxinzelelo, kunye notshintsho lwesakhiwo ibalulekile. Iindlela ezininzi zokulinganisa uxinano lolwelo zidibanisa ii-sensors zobushushu kunye noxinzelelo, zisebenzisa iitafile zokulungisa izinto okanye ii-algorithms zekhompyutha ezenzekelayo zokulungiswa kwe-feed-forward ngexesha langempela. Iimitha zetyhubhu ezidlidlizayo zeLonnmeter zisebenzisa iimodeli zokulinganisa ukulinganisa iimpembelelo zokusingqongileyo kwi-sensor oscillation. Kwimidiya ye-multicomponent, ukufundwa koxinano kunokulungiswa kusetyenziswa imixube yesalathiso okanye iindlela zokulinganisa ezihambelana nolwakhiwo lwenkqubo olulindelekileyo. Imbuyekezo yokwahlulwa kwesigaba—njenge-emulsions yamanzi eoyile okanye ukumiswa kwepolymer—inokufuna iiprobe ezongezelelweyo okanye i-sensor fusion ukuze kwahlulwe iinxalenye ze-particle, igesi, kunye nolwelo.
Ukuhlanganiswa kweDatha yoXinzelelo loLwakhiwo ukuze kuphuculwe inkqubo yeReactor
Ukubaluleka kweDatha yeXesha langempela kwiPolimerization Visualized Through Control Strategies
Ukubeka iliso rhoqo kuxinano lomxube wempendulo kubalulekile kwinkqubo yokwenza i-polyethylene polymerization. Ukulinganiswa koxinano rhoqo kwenza ukuba i-reactor isebenze ngokukhuselekileyo ngokuvumela ukubonwa ngokukhawuleza kokuphambuka okunokubangela ukunyuka kobushushu obuyingozi okanye kubangele ukuveliswa kwe-polymer engaqhelekanga. Ukugcina uxinano lolwelo oluzinzileyo kuqinisekisa ukuba i-polyethylene ephumayo inobunzima obufanayo beemolekyuli kunye neempawu zoomatshini, ezibalulekileyo kuzo zombini iiklasi zeemveliso kunye neemveliso ezikhethekileyo.
Amaqhinga okulawula i-PID (Proportional-Integral-Derivative) asebenzisa impendulo yoxinano lwexesha langempela ukuze alungise iiparameter ze-reactor ngokuguquguqukayo. Xa izinzwa—ezifana neemitha zoxinano olungaphakathi kwiLonnmeter—zibonelela ngedatha yolwelo yokulinganisa uxinano oluqhubekayo, inkqubo yolawulo ihlaziya amazinga okutya kwe-ethylene, iidosi ze-catalyst, kunye neendawo zokubeka ubushushu ngoko nangoko. Olu tshintsho, oluqhutywa yimpendulo yoxinano, lulwa nokuphazamiseka kwaye luzinzise i-reactor ye-polymerization, nto leyo ekhokelela ekuthembekeni okuphezulu kwenkqubo kunye nokhuseleko lokusebenza.
Uhlalutyo lovakalelo lubonisa ukuba izinto eziguquguqukayo ezifana nokuhamba kwe-monomer kunye ne-catalyst, kunye nobushushu bokusabela, zichaphazela ngokuthe ngqo uzinzo lwe-polymerization reactor. Utshintsho oluncinci kumazinga okutya okanye uxinano lwe-catalyst lunokwanda, okubangela utshintsho loxinano, ukuba alujongwanga, lunokubangela iindawo ezishushu okanye ukuguqulwa okungenakulunga. Ukusetyenziswa kwedatha yexesha langempela kuvumela abalawuli be-PID ukuba balungise kwangaphambili iindawo ezibalulekileyo, bagcine ingqibelelo yenkqubo. Umzekelo, ulawulo lwe-PID oluhambelanayo, oluxhomekeke kwizibonakaliso zoxinano oluphilayo, lunokumelana ngokuchanekileyo notshintsho olukhawulezileyo lwe-feedstock compositional, luthintele iimpendulo ezibalekayo kwaye lugcine iipropati ze-polyethylene ezihambelanayo.
Ukudibanisa idatha yoxinano nomgangatho wemveliso kunye nokusebenza kakuhle kwenkqubo
Ukulinganisa uxinano lolwelo ngexesha langempela kubonelela ngengqiqo enokwenzeka malunga nokuguquguquka kwangaphakathi kwe-polymerization reactor kunye nomgangatho wokugqibela wemveliso. Iindlela zoxinano zivumela ukubonwa kokuguquguquka okunxulunyaniswa nokuxubana okubi, ukulahleka ngokuchanekileyo kobushushu, okanye ukuhla komsebenzi we-catalyst. Olu tshintsho lunokubonisa iindawo ezishushu ezikwindawo ethile—iindawo zokusabela okugqithisileyo—ezinokubangela iimpawu ze-polymer ezingafunekiyo kunye nomngcipheko owandisiweyo wokungcola.
Ngokudibanisa idatha yolwelo lokulinganisa uxinano ekusebenzeni kwe-reactor, abaqhubi banokuqhubeka nokulungisa amazinga okutya, ukunikezelwa kwe-catalyst, kunye neemeko zobushushu ukuze kuliwe nokuphambuka koxinano. Utshintsho olusekelwe kuxinano oluhamba phambili lunciphisa ukungcoliswa, kuba luthintela iimeko ezikhuthaza ukwakheka kwe-polymer okanye ii-oligomers eziwohlokileyo kwiindonga ze-reactor. Ulawulo oluphuculweyo loxinano luguqulela kwiinkqubo zokukhupha i-absorption ezisebenzayo ngakumbi ngaphakathi kwe-reactor, zixhasa iindlela ezingcono zokukhupha igesi kunye neendlela zokukhupha i-demur kwimveliso ye-polyethylene.
Imiboniso yedatha—njengeetshathi zendlela yoxinano—ziluncedo ekudibaniseni utshintsho olubonakalayo loxinano nohlengahlengiso lwenkqubo esezantsi. Cinga ngomzekelo olandelayo wetshathi yoxinano lwexesha langempela kwi-reactor ye-loop:
Njengoko kubonisiwe, ukufunyanwa ngexesha elifanelekileyo kokuncipha koxinano kuqalisa ukunyuka kwangoko komthamo we-catalyst kunye nokwehla okuncinci kobushushu, nto leyo eqinisekisa ukuba imveliso yenkqubo iyaqina. Isiphumo kukuncipha kokungcola, amazinga okuguqulwa kwe-monomer aphucukileyo, kunye nokuhambelana okuphezulu kwiziphumo zokusabela kwe-polyethylene polymerization.
Ngamafutshane, ukujonga uxinano lolwelo oluqhubekayo, olungaphakathi—olufezekiswe ngeendlela zokulinganisa uxinano lolwelo olufana nolo luyilwe yiLonnmeter—luqinisekisa indima yalo kuyilo kunye nokusebenza kwe-polymer reactor ephucukileyo, oluchaphazela ngokuthe ngqo inkqubo yemveliso ye-polyethylene ngokuxhasa ukulungiswa komgangatho wemveliso kunye nokuphuculwa kokusebenza kakuhle kwenkqubo.
Iinkqubo zokuFunxa ukuFunxa kwiMveliso yePolyethylene
Ukufunxa kunye nokukhupha i-dynamics zibalulekile kwinkqubo ye-polyethylene polymerization, elawula intshukumo kunye nokuguqulwa kweegesi ze-monomer njengoko zidibana neendawo ze-catalyst ngaphakathi kwe-polymerization reactor. Ngexesha le-polyethylene polymerization reaction, ii-monomer molecules zifunxwa kumphezulu we-catalyst. Oku kuthathelwa kuxhomekeke kwiipropati ze-molecular ze-monomer—ezifana nobunzima, i-polarity, kunye ne-volatility—kunye nendawo yeekhemikhali ngaphakathi kwe-reactor. Ukukhupha i-desorption, ngokuchaseneyo, yinkqubo apho ezi molecules zifunxwayo zisuswa kwaye zibuyele kwisigaba esikhulu. Isantya kunye nokusebenza kakuhle kwezi nkqubo kuchaphazela ngokuthe ngqo ukufumaneka kwe-monomer, ukukhula kwe-polymer, kunye nemveliso iyonke ye-reactor.
Amandla okufunxa alinganisa umqobo ekufuneka imolekyuli yemonomer iwusoyise ukuze iphume kumphezulu we-catalyst. Izifundo zeParameterization zibonisa ukuba la mandla axhomekeke kakhulu kwimo yemolekyuli yemonomer kunohlobo oluthile lomphezulu, nto leyo evumela iimodeli zokuqikelela ngokubanzi kwiinkqubo ezahlukeneyo ze-reactor. Ubomi bokufunxa, okanye ixesha eliqhelekileyo imolekyuli ehlala ifunxa, inovelwano kakhulu kubushushu ngaphakathi kwe-reactor. Amaqondo obushushu aphantsi andisa ubomi, anokunciphisa amazinga okusabela, ngelixa amaqondo obushushu aphezulu ekhuthaza ukujika ngokukhawuleza, okuchaphazela uxinano lwemveliso ye-polyethylene.
Ukuthathwa kwe-monomer kunye nokusebenzisana kwe-catalyst akulawulwa kuphela yi-kinetics ye-first-order. Uphando lwakutshanje lubonisa ukuba ukuziphatha kwe-desorption okuxhomekeke kwi-coverage kunokwenzeka, apho ukusebenzisana kwe-adsorbate-adsorbate kuqhuba i-non-linear kinetics, ingakumbi kwiindawo eziphezulu zokugubungela umphezulu. Umzekelo, njengoko umphezulu we-catalyst ugcwala, ukufunxa kokuqala kuqhubeka kancinci kwaye kuthe ngqo de ukufunxa komphezulu kwehle ngaphantsi komda obalulekileyo, apho ukufunxa ngokukhawuleza kukhawulezisa khona. Olu tshintsho kufuneka luqwalaselwe kuyilo kunye nokusebenza kwe-polymer reactor, njengoko luchaphazela ukusebenza kakuhle kokusetyenziswa kwe-monomer kunye nokungaguquguquki kwemveliso ye-polymer.
Ukudibanisa idatha yokufunxa kunye nokufunxa kunye neendlela zokulinganisa uxinano lwexesha langempela kubalulekile ekugcineni inkqubo yokuvelisa i-polyethylene ezinzileyo. Iimitha ezikwimigca ethe tyaba ezenziwe yiLonnmeter zibonelela ngempendulo eqhubekayo kuxinano lwesigaba solwelo, zibonisa utshintsho oluncinci kuxinano lwe-monomer kunye namazinga okukhula kwe-polymer. Njengoko ukufunxa kuzisa ii-monomers kwindawo yokusabela—kwaye ukufunxa kususa iimolekyuli ezichithiweyo okanye ezigqithisileyo—nakuphi na ukungalingani okanye utshintsho lwe-kinetic kuya kubonakala ngokuthe ngqo kufundo loxinano, okuvumela ukulungiswa okukhawulezayo kokusebenza. Umzekelo, ukuba ukufunxa kukhawulezisa ngokungalindelekanga, ukwehla koxinano olulinganisiweyo kunokubonisa ukusetyenziswa okungaphantsi kwee-monomers okanye ukucima i-catalyst, okukhokelela abaqhubi ukuba batshintshe amazinga okutya okanye iiprofayili zobushushu.
Umfanekiso 1 ongezantsi ubonisa ulwalamano phakathi kokufunxwa kwe-monomer kunye namazinga okufunxwa, ukugqunywa komphezulu, kunye noxinano oluvelayo lwe-liquid kwi-reactor eqhelekileyo ye-polyethylene polymerization, ngokusekelwe kwiimeko ezilinganisiweyo:
| Ubuninzi (g/cm³) | Ubungakanani beMonomer (%) | Izinga lokufunxa | Izinga lokufunxa |
|------------------|- ...|--------------------|
| 0.85 | 90 | Phezulu | Phantsi |
| 0.91 | 62 | Phakathi | Phakathi |
| 0.94 | 35 | Phantsi | Phezulu |
Ukuqonda ezi ntshukumo kunye nokudibanisa iindlela ezichanekileyo zokulinganisa uxinano lolwelo, ezifana nezo zifumaneka kwiLonnmeter, kuvumela ulawulo oluqinileyo kwinkqubo ye-polyethylene polymerization. Oku kuqinisekisa ukuhambelana kwemveliso, isivuno esiphezulu, kunye nokusetyenziswa kakuhle kwe-catalyst kuyo yonke imveliso eqhubekayo.
Iindlela ezilungileyo zokulinganisa uxinano oluchanekileyo kwiNkqubo yePolyethylene Polymerization
Ukulinganiswa koxinano oluqinileyo kubalulekile ekulawuleni ngokuchanekileyo impendulo ye-polyethylene polymerization. Ukulinganiswa koxinano lolwelo olungaphakathi kule ndawo.
Amaqhinga okuSampulu: Ukukhupha ulwelo oluMmeleyo okanye ukulinganisa ukuhamba kolwelo okuqhubekayo
Ukulinganiswa ngokuchanekileyo koxinano lolwelo kwiireactor zepolymerization kuxhomekeke kuyilo olusebenzayo lwesampulu. Iindlela zokukhupha ezimeleyo zisebenzisa imilomo ye-isokinetic ukuthintela ukuphambuka kwesampulu, kunye nezixhobo zenkqubo ezifana neevalvu zokwahlukanisa kunye nee-sampulu coolers ezigcina ukuthembeka kwesampulu ngexesha lokudluliselwa. Umngcipheko ophambili wokukhupha kukulahlekelwa ziinxalenye eziguquguqukayo okanye utshintsho kulwakhiwo lwepolymer ukuba isampulu ayicinywanga okanye ayipholiswanga ngokukhawuleza. Ukulinganiswa koxinano oluqhubekayo kusetyenziswa ii-inline Lonnmeter sensors kubonelela ngedatha yexesha langempela ebalulekileyo kwinkqubo yokuvelisa i-polyethylene; nangona kunjalo, le ndlela ifuna ukuphathwa kwemicimbi efana nokungcoliswa, ukwahlulwa kwesigaba, okanye amaqamza anokonakalisa ukuchaneka. Uyilo lokukhupha ulwelo oluqhubekayo lubonisa ukuphinda kusetyenziswe i-solvent ukuze kugcinwe iimeko ezizinzileyo, kunye nokuseta kwamanqanaba amaninzi kunye nokumelwa kwesampulu okuzenzakalelayo kunye nexesha lokuphendula. Ukukhethwa phakathi kweendlela ezihlukeneyo neziqhubekayo kuxhomekeke kubukhulu benkqubo kunye neemfuno zempendulo enamandla, kunye nempendulo eqhubekayo yexesha langempela edla ngokukhethwa kulawulo lwe-polymer reactor.
Impazamo yokunciphisa umlinganiselo: Iziphumo zeGradients zobushushu, ulwahlulo lwesigaba, kunye neMidiya yeViscosity ephezulu
Impazamo yokulinganisa kwi-density sensitization ivela ikakhulu kwi-gradients yobushushu, ukwahlulwa kwesigaba, kunye ne-viscosity ephezulu. Ii-gradients zobushushu ngaphakathi kwe-reactor, ingakumbi kwisikali, zibangela utshintsho lwendawo kwi-fluid density, nto leyo eyenza kube nzima ukuphendula kwe-sensor. Ukwahlulwa kwesigaba phakathi kwe-polymer-rich kunye ne-solvent-rich domains kukhokelela kwi-density heterogeneity—ii-sensors ezikufutshane ne-interfaces zinokubonelela ngedatha engachanekanga okanye engeyiyo emeleyo. I-viscosity ephezulu, eqhelekileyo kwi-polymerizing media, ithintela ukulingana kwe-thermal kunye ne-compositional, inyusa ukulibaziseka kunye nempazamo kwimpendulo ye-sensor. Ukunciphisa ezi ziphumo, uyilo lwe-reactor kufuneka lubeke phambili ukuxubana okufanayo kunye nokubekwa kwe-sensor yesicwangciso, ukuqinisekisa ukuba ii-sensors zikhuselekile okanye zahlulwe kwi-interfaces yesigaba sendawo. Izifundo ze-Empirical zigxininisa unxibelelwano phakathi kwe-thermal gradients ebekwe kunye nokusebenza kwe-sensor, ukufumana ukwanda kobukhulu beempazamo kwiindawo ze-reaction ezibonisa ukuxubana okubi okanye utshintsho olukhawulezayo lwesigaba. Imodeli yokuqikelela esebenzisa i-Cahn-Hilliard edibeneyo, i-Fourier heat transfer, kunye neendlela zokulinganisela uluntu ibonelela ngezicwangciso zokulindela nokulungisa i-inhomogeneities, ngaloo ndlela iphucula ukuthembeka kokulinganisa i-inline liquid density.
Ukuqinisekiswa ngeNdlela yokulinganisela abantu kunye neendlela zokubonisa i-CFD
Ukuqinisekiswa kokulinganiswa koxinano lolwelo kwi-reactors ze-polyethylene polymerization kwenziwa ngokuqhagamshela idatha ebonwe ngexesha langempela kwizibikezelo ezisekelwe kwimodeli. Iimodeli zebhalansi yabemi (ii-PBM) zilandelela ukukhula kunye nokusasazwa kwee-particles ze-polymer, zibala umahluko kumsebenzi we-catalyst, ubunzima be-molecular, kunye namazinga okutya. I-Computational fluid dynamics (i-CFD) ilinganisa i-reactor hydrodynamics, ukuxuba, kunye neeprofayili zobushushu, inika ulwazi kwiimeko ze-sensor ezilindelekileyo. Ukudibanisa ii-PBM kunye ne-CFD kubonelela ngoqikelelo oluphezulu lokusasazwa kwesigaba kunye notshintsho loxinano kuyo yonke i-reactor. Ezi modeli ziqinisekiswa ngokuthelekisa imveliso yazo ngokuchasene nokufundwa kwe-sensor yokwenyani-ingakumbi phantsi kweemeko zesikhashana okanye ezingezizo ezifanelekileyo. Izifundo zibonisa ukuba iiframeworks ze-CFD-PBM zinokuphinda utshintsho loxinano olulinganisiweyo, zixhasa ukuthembeka kokulinganisa kunye nokwenza ngcono uyilo lwe-reactor. Uhlalutyo lovakalelo, ukuthelekisa impendulo yemodeli kutshintsho kwiiparameter zokusebenza ezifana nobushushu okanye izinga lokuxuba, kuphucula ngakumbi ukuchaneka kunye nokukwazi ukuxilonga. Ngelixa isivumelwano semodeli siqinile phantsi kweemeko ezininzi, ukuphuculwa okuqhubekayo kuyimfuneko kwi-viscosity ephezulu okanye ukungafani, apho ukulinganisa ngokuthe ngqo kuhlala kungumngeni. Iitshati ezilinganisa impazamo yoxinano xa kuthelekiswa negradient yobushushu, ubunzima bokwahlulwa kwesigaba, kunye ne-viscosity zibonelela ngezikhokelo ezibonakalayo zendlela engcono yokusebenza kunye nokuqinisekiswa kwemodeli eqhubekayo.
Iingqwalasela zoLawulo oluPhambili kwi-Polymerization Reactors
Ukudibanisa imodeli yeComputational Fluid Dynamics (CFD) kunye nedatha yovavanyo kubalulekile ekuqhubeleni phambili ulawulo kwi-polymerization reactors, ingakumbi kwinkqubo ye-polyethylene polymerization. I-CFD ivumela ukulinganisa okuneenkcukacha kakhulu kokuhamba kolwelo, ukuxuba, ukusasazwa kobushushu, kunye nokusebenza kakuhle kokuxuba ngaphakathi kwe-polymerization reactor. Ezi zibikezelo ziqinisekiswa zizifundo zovavanyo, zihlala zine-model reactors ezisebenzisa imikhumbi ebonakalayo kunye nokulinganisa okusekwe kwi-tracer kokusasazwa kwexesha lokuhlala. Xa iiprofayili zoxinano olulinganisiweyo noluvavanyiweyo zihambelana, kuqinisekisa imodeli echanekileyo yeemeko zenkqubo yehlabathi lokwenyani, njengokusasazwa kwe-reactant efanayo kunye nolawulo lobushushu ngexesha le-polyethylene polymerization reaction. Ukubeka iliso kwinkqubo esekelwe kuxinano kunika ingxelo ethe ngqo kokubini ukuchaneka kwemodeli kunye nolawulo lokusebenza kwemihla ngemihla, okuvumela ukuchongwa kweendawo ezifileyo okanye ukuxuba okunganelanga ngaphambi kokuba kuchaphazele umgangatho wemveliso okanye ukhuseleko.
Ukuqinisekiswa kwe-CFD ngeemilinganiselo zovavanyo kubalulekile ekunciphiseni umngcipheko. Ukuxubana kakubi kwiireactors zepolymerization ezinoxinzelelo oluphezulu kunokubangela ubushushu obuphezulu (ii-hot spots), okunokubangela ukubola kwe-initiator engalawulwayo, ingakumbi xa kusetyenziswa iiperoxides. Ii-hot spots zihlala zibaleka ukubonwa kweprobe yobushushu obuqhelekileyo kodwa zibonakala ngotshintsho olukhawulezayo kuxinano lwendawo. Idatha yolwelo lokulinganisa uxinano lwexesha langempela, njengoko iveliswa zi-inline sensors ezifana nezo zivela kwiLonnmeter, inika ulwazi oluyi-granular malunga nokungafani kokuhamba kunye neendawo zokuguqula kuyo yonke i-reactor. Ukubeka iliso kuxinano lolwelo kwiindawo ezibalulekileyo kuvumela abaqhubi ukuba babone uhambo oluvela ngaphandle, baqalise izenzo zokulawula ngaphambi kokuba kwenzeke isiganeko sokubaleka kobushushu. Ukuthintela iimeko ezinjalo zokubaleka kuqinisekisa ukhuseleko kwaye kuqinisekisa ukusetyenziswa kakuhle kweperoxide, kunye nokunciphisa imveliso engaqhelekanga ngenxa yokunyuka kwesantya sepolymerization.
Enye into echaphazeleka kakhulu kukujonga uxinano kukulawula ukusasazwa kobunzima bemolekyuli (MWD). Ukuguquguquka kwe-MWD kuchaphazela zombini iimpawu zoomatshini kunye nokuqhubekeka kwe-polyethylene. Idatha yoxinano lwe-granular, yexesha langempela ivumela ukuqonda okungangqalanga, kodwa okukhawulezayo kweendlela ze-MWD. Amaqhinga olawulo asekelwe kwimodeli, axhomekeke kumaxabiso olwelo lokulinganisa uxinano kwi-intanethi, alungisa amazinga okutya okuqala kunye neeprofayili zokupholisa ngokuguquguqukayo ngokuphendula kutshintsho loxinano, ukunciphisa ukuguquguquka kwe-MWD kwi-batch kunye nokuqinisekisa iipropati ezichanekileyo ze-polyethylene. Izifundo zokulinganisa kunye nezifundo eziqinisekisiweyo ziqinisekisa ukuba ukugcina uxinano oluzinzileyo kuthintela ukuziphatha okungafunekiyo kwe-nucleation okanye i-crystallization, kuxhasa ukuveliswa kwamanqanaba e-polyethylene amathathu aneempawu ezijoliswe kuzo.
Ukuze kuphuculwe ukusebenza kakuhle kokuguqula, uyilo kunye nokusebenza kwe-reactor kufuneka kusebenzise ukuxubana okulungiselelweyo kunye nokupholisa kwangaphakathi, okukhokelwa yimilinganiselo yoxinano oluqhubekayo. Kwi-autoclave reactors zanamhlanje ezijikeleza i-multizone, uyilo oluqhutywa yi-CFD oluxhaswa yidatha yoxinano olungaphakathi lukhokela ukubekwa kwee-baffles zangaphakathi kunye nee-riser cooling coils. La manyathelo aqinisekisa ukuba i-phase enye, anciphisa amathuba okuba indawo eshushu, kwaye aphucule ukuguqulwa. Umzekelo, ukwazisa ukupholisa kwangaphakathi okukhokelwa yi-density mapping kukhokelele ekwandeni okuxeliweyo kwe-~7% kokuguqulwa kwe-ethylene ngexesha lenkqubo yokuvelisa i-polyethylene, kunye neeprofayili zobushushu ezifanayo. Ukulungiswa kwe-topology okusekwe kuxinano kukwazisa i-manifold geometry kunye nolungiselelo lwe-flow-channel, okukhokelela ekuphuculweni kokusetyenziswa kwe-reactant kunye nokufana kwemveliso okuphezulu.
Enyanisweni, ukulinganisa uxinano lolwelo kwiireactors zepolymerization akusisixhobo sokuqinisekisa inkqubo kuphela, kodwa sibalulekile kwimpendulo yexesha langempela kunye nolawulo lomngcipheko. Izinzwa eziphambili ezikwi-intanethi, ezifana ne-vibrating element kunye neentlobo zoxinzelelo oluhlukileyo ezivela kwiLonnmeter, zivumela ukulandelela uxinano oluqinileyo noluchanekileyo phantsi koxinzelelo oluphezulu kunye nobushushu, olufanelekileyo kwindawo ye-polyethylene polymerization. Ukuhlanganiswa kwazo kwiinkqubo zolawulo lwenkqubo ezenzekelayo kuxhasa ukulawulwa okuqinileyo kwe-kinetics yenkqubo yokufunxa ukufunxa, kunciphisa ukuphambuka kobunzima be-molecular, kwaye kuqinisekisa ukhuseleko lwereactor.
Ukusetyenziswa ngempumelelo kweCFD ngokubanzi, okuqinisekiswe ngedatha yokulinganisa uxinano ngexesha langempela kunye nelovavanyo, kuxhasa iindlela zanamhlanje kuyilo kunye nokusebenza kwe-polymer reactor. Ukusebenzisa ezi ndlela kuvumela abaqhubi ukuba bandise isivuno, banciphise umngcipheko, kwaye balawule ngokuqinileyo iimpawu zomgangatho ezibalulekileyo zempendulo ye-polyethylene polymerization.
FAQ
Ulinganisa njani uxinano lolwelo ngexesha lenkqubo ye-polyethylene polymerization?
Uxinano lolwelo kwinkqubo ye-polyethylene polymerization lulinganiswa kusetyenziswa ii-in-situ sensors ezifana ne-vibrating-tube densitometers okanye izixhobo ze-ultrasonic. Ezi zixhomekeke kutshintsho kwi-resonance frequency, i-impedance, okanye i-phase shifts njengoko ulwelo ludibana nomphezulu we-sensor. Ii-Ultrasonic sensors, ngokukodwa, zibonelela ngohlalutyo olukhawulezayo nolwexesha langempela kwaye zisebenza ngokufanelekileyo phantsi kweemeko ezinzima zoxinzelelo oluphezulu kunye nobushushu obuqhelekileyo kwii-reactors ze-polymerization. Ukulandelela ngexesha langempela kuvumela ukubonwa kotshintsho olukhawulezayo loxinano, olubalulekileyo ekuxhaseni ulawulo lwenkqubo oluzenzekelayo kunye nokugcina umgangatho wemveliso kulo lonke ukusabela. Uphuhliso lwakutshanje kwi-piezoelectric micromachined ultrasonic transducers luvumela i-miniaturization, ukuchaneka okuphezulu, kunye nokuhlanganiswa okuqinileyo kunye nokuseta kwemizi-mveliso ukuze kuhlolwe uxinano oluqhubekayo.
Idlala yiphi indima ukulinganisa uxinano lolwelo kwi-reactor ye-polymerization?
Ukulinganisa ngokuchanekileyo uxinano lolwelo kubalulekile ekusebenzeni kwe-reactor ye-polymerization. Ivumela abaqhubi ukuba bajonge uxinano lwe-reactant, babone ukwahlulwa kwesigaba, kwaye baphendule ngokuguquguqukayo kwiinguqu zenkqubo. Umzekelo, ukufundwa koxinano kuvumela uhlengahlengiso olukhawulezileyo kwi-catalyst dosage, amazinga okuxuba, okanye iiprofayili zobushushu—iiparameter ezichaphazela ngokuthe ngqo i-kinetics kunye nokukhetha kwe-polyethylene polymerization reaction. Ukukwazi ukubona utshintsho loxinano ngexesha langempela kunceda ukugcina usasazo olufunekayo lwe-molecular weight, amazinga okuguqulwa kwe-reaction, kunye nomgangatho we-polymer ohambelanayo.
Iyintoni inkqubo yokufunxa kwaye idibana njani nomlinganiselo woxinano?
Inkqubo yokufunxa ukufunxa kwi-polymerization reactors ibhekisa kwi-monomers ezinyibilika, okanye ezikhutshwayo, kwi-reaction medium. Xa ii-monomers okanye iigesi zifunxwa, uxinano lolwelo luyatshintsha, lubonisa ukwanda koxinano lwe-solute; xa kuphuntswa ukufunxa, uxinano luyancipha njengoko izinto ziphuma kwi-liquid phase. Ukubeka esweni olu tshintsho loxinano kubalulekile ekufumaneni iziganeko zokuthathwa okanye ukukhululwa kwaye kubonelela ngengqiqo ngenkqubela phambili ye-polymerization, imeko yokulingana kwesigaba, kunye nozinzo ngaphakathi kwi-reactor. Ukulandelela okunamandla koxinano ekuphenduleni ukufunxa kunye nokufunxa kwenza ukuba kuphuculwe imodeli yokudluliselwa kobuninzi kunye nokwandiswa okusebenzayo kwi-industrial reactors.
Kutheni ukulinganisa uxinano kubalulekile kwinkqubo yokwenza i-polyethylene polymerization?
Ukulinganiswa koxinano kubalulekile ukuqinisekisa ulawulo olufanelekileyo lwenkqubo kwi-polyethylene polymerization. Inika ingxelo ekhawulezileyo malunga nokwakheka kwangaphakathi kwe-reactor, ivumela ukulungiswa kakuhle kokusetyenziswa kwe-catalyst, umlinganiselo womxube, kunye neemeko zobushushu. Ezi zinto azichaphazeli kuphela ubunzima beemolekyuli kunye namazinga okuguqulwa kodwa zikhusela nakwiibhetshi ze-polymer ezingezizo ezicwangcisiweyo. Ukulinganiswa ngokuthe ngqo koxinano kuxhasa ukusebenza okukhuselekileyo, kwandisa ukusebenza kakuhle kwezixhobo, kwaye kuphucula ulawulo lwamandla, kuphucula ukufana kwemveliso yokugqibela kuyo yonke imijikelo yemveliso.
Uhlobo lwereactor luyichaphazela njani indlela yokulinganisa ulwelo loxinano?
Uyilo kunye nokusebenza kwee-reactors ze-polyethylene polymerization—ezifana nee-reactors zebhedi ezinyibilikisiweyo (ii-FBR) kunye nee-reactors zetyhubhu ezinoxinzelelo oluphezulu (ii-HPTR)—zimisela amaqhinga okulinganisa uxinano asetyenziswayo. Ii-FBR zizisa imingeni efana nokusasazwa kwee-particle ezahlukeneyo kunye nokuhamba kwegesi okuqinileyo kwizigaba ezininzi, ezifuna ii-sensors ezisombululwe ngokwendawo ezikwaziyo ukulandelela utshintsho olukhawulezayo loxinano. Izixhobo zokulinganisa (ezifana ne-CFD kunye ne-DEM) kunye neemitha zoxinano eziqinileyo ezilungiselelwe iimeko zezigaba ezininzi zibalulekile ekubekweni esweni ngokuchanekileyo. Ii-HPTR, ngokwahlukileyo, zifuna ii-sensors ezincinci, ezimelana noxinzelelo, kunye nempendulo ekhawulezayo ukuze zisebenze phantsi kweemeko ezixineneyo nezixineneyo. Ukukhethwa kunye nokubekwa kwee-sensor ezifanelekileyo kuqinisekisa ukuveliswa kwedatha okuthembekileyo, ukugcina uzinzo lwenkqubo kunye nokuxhasa ukwanda okusebenzayo kuzo zombini iintlobo zee-reactor.
Ixesha leposi: Disemba-16-2025
