Mokhoa oa ho hlahisa polyethylene ke eng
Mokhoa oa tlhahiso ea polyethylene o ka aroloa ka:
- Mokhoa o phahameng oa khatello, mokhoa o phahameng oa khatello o sebelisoa ho hlahisa polyethylene e tlaase.
- Khatello e bohareng
- Mokhoa o tlase oa khatello. Mabapi le mokhoa o fokolang oa khatello, ho na le mokhoa oa slurry, mokhoa oa tharollo le mokhoa oa khase ea khase.
Mokhoa oa khatello e phahameng o sebelisoa ho hlahisa polyethylene e tlaase. Mokhoa ona o ile oa hlahisoa esale pele. Polyethylene e hlahisoang ke mokhoa ona e na le hoo e ka bang 2/3 ea kakaretso ea polyethylene, empa ka tsoelo-pele ea theknoloji ea tlhahiso le li-catalysts, sekhahla sa eona sa ho hōla se bile ka morao haholo ka mor'a mokhoa o tlaase oa khatello.
Mabapi le mokhoa o fokolang oa khatello, ho na le mokhoa oa slurry, mokhoa oa tharollo le mokhoa oa khase ea khase. Mokhoa oa slurry o sebelisoa haholo-holo ho hlahisa polyethylene e phahameng, ha mokhoa oa tharollo le mokhoa oa khase o ke keng oa hlahisa polyethylene e phahameng, empa hape o hlahisa polyethylene ea mahareng le e tlaase ka ho eketsa li-comonomers, tse tsejoang hape e le linear low density polyethylene. vinyl. Mekhoa e fapaneng ea khatello e tlase e ntse e tsoela pele ka potlako.
Mokhoa oa Khatello e Phahameng
Mokhoa oa ho etsa polymerizing ethylene ho polyethylene e tlase-tlase ho sebelisa oksijene kapa peroxide joalo ka moqali. Ethylene e kena ka har'a mochine ka mor'a khatello ea bobeli, 'me e entsoe ka polymerized ka polyethylene tlas'a khatello ea 100-300 MPa, mocheso oa 200-300 ° C le ketso ea initiator. Polyethylene ka mokhoa oa polasetiki e fetisoa le pelletized ka mor'a ho eketsa lisebelisoa tsa polasetiki.
Li-reactors tsa polymerization tse sebelisoang ke li-tubular reactors (tse bolelele ba li-tube ho fihla ho 2000 m) le li-reactors tsa tanka. Sekhahla sa phetoho ea palo e le 'ngoe ea ts'ebetso ea tubular ke 20% ho 34%,' me matla a selemo le selemo a tlhahiso ea mohala o le mong ke 100 kt. Sekhahla sa phetoho ea pase e le 'ngoe ea mokhoa oa kettle ke 20% ho isa ho 25%, mme matla a tlhahiso ea selemo le selemo a 180 kt.
Mokhoa o Tlase oa Khatello
Ena ke mokhoa o mong oa tlhahiso ea polyethylene , e na le mefuta e meraro: mokhoa oa slurry, mokhoa oa tharollo le mokhoa oa khase ea khase. Ntle le mokhoa oa tharollo, khatello ea polymerization e ka tlase ho 2 MPa. Lefutsoral mehato e kenyeletsa ho lokisa catalyst, ethylene polymerization, karohano ea polymer le granulation.
①Mokhoa oa seretse:
Polyethylene e hlahisoang e ne e sa qhibilihe ka har'a mokelikeli 'me e ne e le ka sebōpeho sa slurry. Maemo a slurry polymerization a bonolo ebile a sebetsa habonolo. Alkyl aluminium e atisa ho sebelisoa e le activator, 'me hydrogen e sebelisoa e le molecular weight regulator,' me tanka ea tanka e atisa ho sebelisoa. Polymer slurry e tsoang tanka ea polymerization e fetisetsoa ka tanka ea flash, karohano ea mokelikeli oa khase ho ea ho se omisang phofo, ebe o granulated. Ts'ebetso ea tlhahiso e boetse e kenyelletsa mehato e kang ho hlaphoheloa ha solvent le ho hloekisa solvent. Li-kettle tse fapaneng tsa polymerization li ka kopanngoa ka letoto kapa ka parallel ho fumana lihlahisoa tse nang le liphaello tse fapaneng tsa boima ba limolek'hule.
②Mokhoa oa tharollo:
Polymerization e etsoa ka solvent, empa ka bobeli ethylene le polyethylene li qhibiliha ka har'a solvent, 'me tsamaiso ea karabelo ke tharollo e ts'oanang. Thempereichara ea karabelo (≥140℃) le khatello (4～5MPa) li holimo. E khetholloa ka nako e khutšoanyane ea polymerization, matla a phahameng a tlhahiso, 'me e ka hlahisa polyethylene e nang le likhahla tse phahameng, tse bohareng le tse tlaase,' me e ka laola hantle thepa ea sehlahisoa; leha ho le joalo, polymer e fumanoeng ka mokhoa oa tharollo e na le boima bo tlase ba limolek'hule, kabo e tšesaane ea boima ba limolek'hule, le thepa e tiileng. Litaba li tlase.
③Mokhoa oa khase:
Ethylene e entsoe ka polymerized sebakeng sa gaseous, generalka ho sebedisa seeactor se nang le metsi. Ho na le mefuta e 'meli ea li-catalysts: letoto la chromium le letoto la titanium, tse kenyelletsoang ka bongata betheng ho tloha tanka ea polokelo,' me ho potoloha ka lebelo la ethylene ho sebelisoa ho boloka metsi a bethe le ho felisa mocheso oa polymerization. Polyethylene e hlahisoang e ntšoa ho tloha tlase ho setsi sa motlakase. Khatello ea mochine oa motlakase e ka ba 2 MPa, 'me mocheso ke 85-100 °C.
Mokhoa oa khase-mohato ke mokhoa oa bohlokoa ka ho fetisisa bakeng sa tlhahiso ea polyethylene e tlaase e tlaase. Mokhoa oa khase ea khase o felisa mokhoa oa ho hlaphoheloa ha solvent le ho omisa polymer, mme o boloka 15% ea matsete le 10% ea litšenyehelo tsa ts'ebetso ha e bapisoa le mokhoa oa tharollo. Ke 30% ea matsete a mokhoa oa khale oa khatello e phahameng le 1/6 ea tefo ea ts'ebetso. Kahoo e tsoetse pele ka potlako. Leha ho le joalo, mokhoa oa mohato oa khase o hloka ho ntlafatsoa ho ea pele ho latela boleng ba sehlahisoa le mefuta e fapaneng.
Mokhoa oa Khatello e Bohareng
Ho sebelisa chromium-based catalyst e tšehetsoeng ka gel ea silica, ka loop reactor, ethylene e entsoe ka polymer ka tlas'a khatello e mahareng ho hlahisa polyethylene e phahameng haholo.
Mokhoa oa ho hlahisa polyethylene ke eng