Taw qhia
Ceramic daim nyias nyias tau dhau los ua cov cuab yeej nyiam rau kev kho dej thiab dej khib nyiab ua tsaug rau lawv cov khoom siv dag zog, tshuaj tiv thaiv, thermal stability, thiab lub neej ua haujlwm ntev piv rau cov khoom siv polymeric. Tab sis zoo ib yam li cov txheej txheem membrane, ceramics raug kev txom nyem los ntawm qhov teeb meem tsis tu ncua: fouling, tshwj xeeb tshaj yog los ntawm yaj thiab macromolecular organic teeb meem xws li humic acids, proteins, thiab natural organic teeb meem (NOM). Fouling txo permeate flux, nce nqi zog, thiab ua rau lub neej luv luv.
Ib txoj hauv kev zoo tshaj plaws los tawm hauv xyoo tas los no yog kev sib koom ua ke cov khoom siv ceramic nrog nanobubble (thiab micro-nanobubble, MNB) generators. Qhov kev sib xyaw no yog siv ob qho tib si los tiv thaiv fouling thaum lub sij hawm pom thiab ntxuav cov membranes uas twb fouled - thiab nyob rau hauv ib co configurations, mus active degrade organic pollutants nyob rau hauv feedwater nws tus kheej.
Nanobubbles yog dab tsi?
Nanobubbles yog cov npuas roj roughly 100-200 nanometers mus rau ob peb micrometers inch - deb me dua li cov npuas uas ua los ntawm cov pa aeration. Vim lawv qhov loj me, lawv coj txawv txawv ntawm cov npuas zoo tib yam:
- Lawv tsis sawv sai sai thiab pop.Nanobubbles muaj nyob ze - nruab nrab buoyancy thiab tuaj yeem nyob twj ywm hauv dej rau hnub lossis lub lis piam es tsis yog vib nas this.
- Lawv nqa tus nqi tsis zoo, uas pab lawv adsorb rau thiab cuam tshuam nrog cov organic foulants thiab cov khoom raug tshem tawm hauv dej.
- Thaum lawv vau, lawv tsim muaj zog shear hauv zos thiab, qee zaum, cov pa oxygen reactive (ROS)xws li hydroxyl radicals (•OH), uas tuaj yeem pab rhuav tshem cov organic molecules.
- Lawv ua rau kom muaj roj ntau ntau ntxiv - mus rau - ua kua dej hloov pauv tau zoo, uas tseem ceeb heev thaum cov roj koom nrog yog cov muaj zog oxidant zoo li ozone.
Nanobubble generators feem ntau tsim cov npuas no siv ib qho ntawm ob peb lub tswv yim: siab -shear rotational/venturi li, pressurized dissolved- roj tso tawm (zoo ib yam li yaj huab cua flotation), los yog ultrasonic cavitation. Cov pa uas siv tau tuaj yeem yog huab cua / oxygen, lossis - rau kev kho mob hnyav dua - ozone.
Vim li cas thiaj muab Nanobubbles nrog Ceramic Membranes?
1. Tiv thaiv fouling thaum lub sij hawm lim
Micro thiab nanobubbles tau ua kom pom qhov ua tau zoo tshaj plaws hauv kev tiv thaiv fouling thiab pab cov membrane tu thoob plaws ntau hom kev pom, thiab hauv crossflow filtration, kev siv cov npuas no rov qab los ntawm ceramic membrane flux mus rau 80% tom qab rov qab ntxuav.Cov npuas feem ntau yog nkag mus rau hauv cov kwj dej los yog siv thaum lub sij hawm rov qab ntxuav, qhov chaw uas lawv pab txhawm rau txhawm rau daim nyias nyias thiab cuam tshuam cov ncuav mog qab zib txheej ntawm cov organic foulants ua ntej nws sib sau ua ke.
2. Cov Tshuaj Kho Kom Zoo-hauv-Qhov Chaw (CIP) Ntxuav nrog Ozone
Tej zaum daim ntawv thov kev tshawb fawb tshaj plaws yog kev sib txuas ntawm ozone nrog nanobubble tiam rau CIP tu ntawm ceramics fouled los ntawm yaj thiab macromolecular organics.Ozone micro-nano-bubble technology tuaj yeem txo cov qauv ntawm foulant txheej ntawm daim nyias nyias, txo cov adhesion ntawm foulants, thiab hydroxyl radicals tsim los ntawm catalysis los ntawm alumina nyob rau hauv lub ceramic membrane tuaj yeem ua tiav kev ntxuav ntawm cov kab mob sib sib zog nqus.Cov nanobubbles muab lub zog shear xav tau rau lub cev tshem tawm cov foulant txheej, thaum tib lub sijhawm ua tiav ntau dua ozone huab hwm coj hloov pauv tau zoo dua li cov pa npuas diffusion - txhais tau tias tsawg dua cov pa roj ozone yog nkim thiab ntau dua ntawm nws ua tau nrog cov foulant.
Ib qho kev tshawb fawb ntsig txog tsimib qho tshiab ozone-nanobubble generator system los ntxuav lub fouled ceramic membrane feem ntau siv hauv kev lag luam dyeing, thiab pom tias cov yam ntxwv ntawm daim nyias nyias tau hloov pauv loj, nrog txo qhov roughness thiab foulant tsub zuj zuj raws li tau lees paub los ntawm atomic force microscopy, scanning electron microscopy, X-ros fluorpyive{2}Fourier-hloov infrared (FTIR) spectroscopy ntawm cov seem foulant pom cov yam ntxwv ntawm cov organic kos npe - hydrogen- pawg sib koom ua ke thiab cov pa roj carbon monoxide unsaturated-carbon bonds - zoo ib yam nrog cov ozone nanobubbles es rhuav tshem cov organic foulant molecules yooj yim dua li lawv.
3. Cua / Oxygen Nanobubbles raws li tus nqi qis dua -Cov nqi hloov pauv
Tsis yog txhua daim ntawv thov yuav tsum tau ozone.Ghadimkhani et al. pom tau tias muaj kev vam meej unclogging ntawm ceramic membrane pores siv cua nanobubbles nyob rau hauv ob qho tib si pilot - thiab lub rooj ntev zaum -scale kev tshawb nrhiav, rov qab permeate flux rau nws cov thawj qhov tseem ceeb.Hauv ib qho kev sim,humic acid tag nrho txhaws lub ceramic membrane li ntawm 6 teev, txo cov flux zero, tab sis thaum lub fouled membrane tau noj nrog nanobubble dej, thawj flux tau rov qab nyob rau hauv 2 teev - ib tug tshwm sim los ntawm kev puas tsuaj ntawm cov organic teeb meem los ntawm dawb radicals generated raws li cov huab cua nanobubbles.Qhov no qhia tau hais tias txawm tias tsis muaj oxidant muaj zog zoo li ozone, lub cev qhuav dej ntawm nanobubbles tuaj yeem tsim kom muaj cov kab mob hauv zos txaus los pab degrade adsorbed organics.
Cov huab cua nanobubbles yog qhov txaus nyiam vim lawv zam lub peev thiab kev nyab xeeb ntawm cov nqi ntawm - qhov chaw ozone tsim, ua rau lawv muaj kev xaiv yooj yim dua rau cov nroj tsuag kho me me lossis kev lag luam xws li kev siv mis nyuj, qhov twg nanobubbles kuj tau pom los txhim kho flux thiab txo lub sij hawm pom.
4. Pretreatment rau downstream Membrane txheej txheem
Ceramic daim nyias nyias kuj tseem raug siv los ua pretreatment kauj ruam ua ntej ntawm cov tawv nqaij nruj zoo li nanofiltration (NF), thiab nanobubble/ozone- cov kev pab cuam tuaj yeem txhim kho qhov kev kho ua ntej ua haujlwm zoo npaum li cas. Hauv ib txoj kev tshawb fawb txog kev haus dej- dej- cog cov dej pov tseg,hybrid ceramic membrane-nanofiltration txheej txheem ua tiav qhov nruab nrab tshem tawm ntawm 95.60% rau yaj cov organic carbon, 98.55% rau UV254 (ib lub npe rau cov organic cov ntsiab lus), 34.50% rau conductivity, thiab 50.71% rau calcium - kev txhim kho ntawm 4.70%, 1.3% thiab 1.40% kev txhim kho. dhau standalone nanofiltration. Ceramic membrane pretreatment kuj txo cov irreversible fouling ntawm downstream NF membrane nyob rau hauv ib tug ntau yam ntawm cov pa phem concentrations, thiab scanning electron microscopy tau lees tias qhov pretreatment alleviated fouling ntawm NF membrane nto.
Cais, ozone-raws li qhov dej ntws tawm tau raug tshawb nrhiav los ua ib txoj hauv kev los txo qhov kev xav tau ntawm cov pa microfiltration / ultrafiltration pretreatment ua ntej ntawm ceramic nanofiltration membranes. Cov pa ua ntej siv ntau- media filtration, microfiltration, lossis ultrafiltration ua ntej nanofiltration ntxiv cov nqi tseem ceeb, lub cev hneev taw, thiab cov txheej txheem tsis yooj yim, yog li hloov qhov pom-raws li pretreatment nrog ozone-raws li txheej txheem yog ib txoj hauv kev zoo los txo nqi thiab hneev taw, tshwj xeeb tshaj yog nyob rau hauv ur chaw nres nkoj.
5. Direct Organic Pollutant Degradation
Tshaj li kev tu daim nyias nyias, micro-nanobubble systems tau kawm ntau ntxiv raws li kev oxidation siab heev- thev naus laus zis nyob ib sab hauv lawv txoj cai.Hauv ib txoj kev tshawb fawb txog kev kho dej khib nyiab, sib txuas lub tshuab hluav taws xob hydrodynamic cavitation nrog cov txheej txheem oxidation ntxiv tau tsa tag nrho cov organic carbon tshem tawm ua haujlwm rau 40.01% tshaj 90 feeb, piv rau tsuas yog 14.61% siv lub cavitation generator ib leeg.Qhov no qhia tau hais tias nanobubble / cavitation systems feem ntau ua tau zoo tshaj plaws raws li ib feem ntawm cov txheej txheem hybrid.
Yuav Ua Li Cas Ib Qhov Txheej Txheem Ua Haujlwm
Ib qho kev sib xyaw ua ke nanobubble-ceramic membrane feem ntau suav nrog:
- Gas muab- ambient cua, oxygen, los yog ozone tsim nyob rau hauv -site.
- Nanobubble generator- ib lub venturi, shear{1}}pump, los yog pressurized- dissolution unit uas txhaj cov roj rau hauv dej li nanobubbles.
- Kev sib cuag / tshuaj tiv thaiv theem- nanobubble- cov dej uas muaj nplua nuj yog noj tsis tu ncua rau hauv cov kwj dej membrane, los yog siv nyob rau hauv lub sij hawm rov qab los / CIP cycles.
- Ceramic membrane module- feem ntau yog alumina, zirconia, lossis titania-raws li tubular lossis tiaj tus-cov ntaub ntawv, ua haujlwm hauv crossflow lossis tuag- kawg hom.
- Saib xyuas- flux thiab transmembrane siab tau taug qab los txiav txim siab thaum twg nanobubble - pab tu lub voj voog yog xav tau.
Qhov zoo ntawm kev sib xyaw ua ke
- Higher flux rov qabtom qab ntxuav, feem ntau tsis muaj tshuaj tua kab mob hnyav.
- Txo kev siv tshuaj lom neeg- tshwj xeeb tshaj yog muaj txiaj ntsig qhov twg ozone nanobubbles hloov lossis txo kev siv cov kua qaub/caustic tu tshuaj.
- Zoo dua huab hwm coj hloov ntawm oxidants, yog li tsawg ozone los yog huab cua yuav tsum tau ua kom tiav cov nyhuv tu tib yam.
- Extended membrane lifespanvim yog softer, kev tu zoo dua piv rau cov tshuaj lom neeg los yog kev tu tshuab.
- Muaj peev xwm ua kom txo tau cov hneev taw pretreatmentThaum siv ua ntej ntawm cov tawv nqaij nruj zoo li NF lossis RO.
Kev txwv thiab qhib cov lus nug
Txawm hais tias tau txais txiaj ntsig zoo, cov kws tshawb fawb tau sau tseg qee qhov sib txawv:
Kev cuam tshuam ntawm npuas loj thiab qhov siab ntawm kev tswj fouling tseem tsis tau nkag siab tag nrho, thiab kev ua haujlwm tsis zoo tuaj yeem yog qhov system - thiab foulant - tshwj xeeb.
Ozone nanobubble systems yuav tsum tau ua tib zoo xyuas cov khoom siv sib xws, tawm -kev tswj hwm roj, thiab kev tswj hwm kev nyab xeeb uas muab ozone toxicity.
Cov txiaj ntsig tshaj tawm feem ntau yog los ntawm lub rooj zaum - lossis tus tsav- ntsuas ntsuas; loj- nplai, ntev- cov ntaub ntawv ua haujlwm lub sijhawm tseem txwv.
Kev ua tau zoo nyob ntawm qhov xwm txheej ntawm cov organic foulant (piv txwv li, humic acids vs. proteins vs. hluavtaws dyes), yog li cov txiaj ntsig tsis tas yuav nthuav dav thoob plaws kev siv.
Xaus
Kev sib koom ua ke ntawm nanobubble generators nrog ceramics sawv cev yog ib qho ntawm cov kev ua tau zoo tshaj plaws hauv kev tswj fouling rau dej thiab dej khib nyiab. Txawm hais tias siv rau kev tiv thaiv fouling thaum pom, ozone- txhim kho CIP tu, lossis ua ntej kho ua ntej nanofiltration, thev naus laus zis siv lub zog tshwj xeeb ntawm nanobubbles - ntev stability, siab nto reactivity, thiab cov roj hloov pauv tau zoo - kom txo tau kev siv tshuaj lom neeg, kev pab cuam lub neej ntev. Raws li cov txheej txheem hauv qab no dhau los ua tus cwj pwm zoo, qhov kev sib xyaw ua ke no zoo li yuav pom kev siv dav dav hauv kev kho dej haus, kev kho dej khib nyiab, thiab kev siv dej rov siv dua.