Membrane ea RO E Finyella Joang 99.9% Ho Hana Letsoai?
Reverse osmosis membrane (RO membrane) e sebetsa ka molao-motheo oa ho hanyetsa ts'ebetso ea tlhaho ea osmotic. Mona ke tlhahlobo e tebileng ea mokhoa oa eona oa ho sebetsa:
Papiso ea 'mele ea Natural Osmosis le Reverse Osmosis
Natural Osmosis Phenomenon ke ha ho na le phapang ea mahloriso mahlakoreng ka bobeli a lera le semipermeable (joalo ka metsi a hloekileng le metsi a letsoai), limolek'hule tsa metsi li tla phalla ka boithatelo ho tloha lehlakoreng le tlase la mahloriso ho ea lehlakoreng le phahameng la mahloriso ho fihlela likhakanyo tsa mahlakore ka bobeli li leka-lekane. Nakong ena, khatello e hlahisoang ke phapang ea bophahamo ba bokaholimo ba metsi ke khatello ea osmotic.
Khatello ea osmotic π ea tharollo e hlapollang ke: π = iCRT (moo ke leng palo ea li-ion tse hlahisoang ke electrolysis ea limolek'hule tsa solute; C ke molar concentration ea solute; R ke molar gas constant; T ke mocheso o felletseng.)
Ka mohlala, khatello ea osmotic ea metsi a leoatle e ka holimo ho 28 bar, e hlokang khatello e kholo ea ho khutlisa ho phalla ha metsi.
"High-Pressure Counter-Flow" ea Reverse Osmosis e sebelisa khatello lehlakoreng la letsoai (> khatello ea osmotic) e qobella limolek'hule tsa metsi hore li phalle ka morao, 'me li fihlele ho falla ho tloha "metsi a letsoai → metsi a hloekileng."
Nakong ea reverse osmosis, sekhahla sa osmotic sa solvent, ke hore, matla a phallo ea metsi N, ke: N=Kh(Δp)－Δπ) (moo Kh e leng hydraulic permeability coefficient, e ntseng e eketseha hanyenyane ka mocheso; Δp ke phapang ea khatello e tsitsitseng ho pholletsa le lera; Δπ ke phapang ea khatello ea osmotic ho pholletsa le lera).
Mothating ona: Lehlakoreng la metsi a hloekileng: Ho bokella limolek'hule tsa metsi tse fetang (ho phunyeletsa), Ka lehlakoreng la metsi a teteaneng: Ho boloka letsoai, litšepe tse boima, le litšila tse ling (concentrate).
Bonepa bo Feteletseng ba Sebopeho sa Membrane
Sebopeho sa sandwich:
Sekhahla sa tšehetso: Lesela le sa lohiloeng (botenya ≈ 120 μm) - "foreimi ea tšepe" e mamellang khatello e phahameng.
Porous layer: Polysulfone material (pore size 0.01-0.1 μm) - "mohala oa pele oa tšireletso" o thibelang seretse, lehlabathe le mafome.
Lera le sebetsang: Filimi ea Polyamide (botenya ≈ 200 nm) - "moahloli oa 'nete oa limolek'hule," ka boholo ba pore ea 0.1-1 nm feela (≈ habeli boholo ba limolek'hule tsa metsi).
Lintlha tsa papiso:
Virus bophara (0.02-0.3 μm) > Membrane pore boholo makhetlo a 3000.
Boholo ba baktheria (0.5-5 μm) > Membrane pore boholo makhetlo a 5000.
Theory ea mohlala ea khale
- Tharollo-Diffusion Model
Core Assumption: Lera ke sebopeho sa homogeneous ntle le li-pores, 'me solute le solvent li fetisetsoa ka ho qhibiliha ka har'a lisebelisoa le ho hasana.
Mokhoa oa phetisetso:
Dissolution: Limolek'hule tsa metsi le solutes li adsorb holim'a lera ebe li qhibiliha ka har'a lera;
Phapang: Tlas'a matla a ho khanna a lik'hemik'hale tse ka bang teng (phapang ea khatello), limolek'hule tsa metsi li hasana ka har'a lera;
Desorption: E lokolloa e le metsi a hloekileng ka lehlakoreng le leng la lera.
Polelo ea lipalo: Phallo ea metsi Jw = A(ΔP − Dp), moo A e leng "membrane permeability coefficient", DP ke khatello e sebelisoang, le Dp ke phapang ea khatello ea osmotic.
- Mohlala o khethehileng oa Adsorption-Capillary Flow Model
Maikutlo a mantlha: Sebaka sa membrane se na le liteishene tsa nanoscale, tseo ka ho khetheha li ratang limolek'hule tsa metsi ho etsa monolayer ea "metsi a tlamiloeng," ha li-solutes li lelekoa.
Mokhoa oa ho fetisa:
Selectional adsorption: Lera la bokaholimo le khetha limolek'hule tsa metsi ka libonto tsa haedrojene (mohlala, carbonyl oxygen in cellulose acetate);
Lipalangoang tsa kanale: Tlas'a khatello e matla, metsi a tlamiloeng a feta likanaleng ka "hydrogen bond jumping," ha li-solutes li bolokoa ka lebaka la ho qheleloa ka thoko ho boholo.
Tshebetso:
Sekhahla sa ho hana letsoai: 98% -99.9% (TDS
Sekhahla sa ho tlosa tšepe e boima:> 99.9% (loto, arsenic, joalo-joalo).
Lintlha tse ka sehloohong tse susumetsang
Khatello ea Ts'ebetso
E tlameha ho ba > tharollo ea khatello ea osmotic, hangata 60-80 bar bakeng sa lisebelisoa tsa indasteri (desalination), le 2-4 bar bakeng sa tšebeliso ea lelapa.
Mocheso: 5-45 ℃ (mocheso o phahameng o baka deformation ea pore ea membrane)
Sebaka sa pH: 4-11 (polyamide membrane), 5-6 (cellulose acetate membrane).
Mofuta oa litšila
Inorganic scaling (mohlala, CaCO₃): E hloka ho hloekisoa ha citric acid ho pH=2
Tšilafalo ea baeloji (mohlala, lifilimi tsa baktheria): E phekoloa ka sanitizer ea DBNPA.
Maemo a Kopo le Khetho ea Mofuta oa Membrane
Ho ntša letsoai metsing a leoatle Polyamide composite membrane (TFC) Ho hanyetsa khatello e phahameng (＞60 bar), 99% sekhahla sa desalination
Ho hloekisoa ha metsi ka tlung ea Spiral composite membrane Ts'ebetso ea khatello e tlase (2-4 bar), ho boloka matla 30%.
Metsi a hloekileng a indasteri (li-chips tsa elektronike) Ultra-low pressure composite membrane Sehlahisoa sa ho hanyetsa metsi 18 MΩ·cm.