Dab tsi yog qhov Fouling Risks ntawm Tsawg Flow Velocities hauv PTFE Exchanger thiab Lawv Yuav Tswj Li Cas?

Yog tias tus nqi ntws tau txo qis rau kev nkag mus, qhov kev poob siab yuav qis, tab sis nws tseem yuav tso cai rau cov ntaub ntawv tshem tawm los kho thiab biofilms kom loj hlob ntawm PTFE raj qhov chaw. Lub PTFE exchanger uas yog hydraulically txaus yuav dhau los ua fouling - cov kab ke yooj yim yog tias qhov nrawm qis dhau rau tus kheej - ntxuav cov dej ntws.

Fouling Mechanisms nyob rau hauv Low Flow Conditions
Lub fouling mechanisms muaj ntau yam sib txawv nyob rau hauv ib tug tsawg khiav ceev fouling PTFE exchanger tshaj nyob rau hauv ib txwm ua hauj lwm tej yam kev mob. Thaum lub nrawm ntawm lub raj sab yog txo qis hauv qab ib ncig ntawm 0.5 m / s lub zog ntawm cov dej ntws tsis txaus los ua kom cov khoom raug tshem tawm.

Nyob rau lub sijhawm no, cov khoom siv tau pib los ntawm lub ntiajteb txawj nqus. Kev ntsuas nrawm yog txiav txim siab los ntawm qhov loj me, qhov ntom ntom thiab cov kua viscosity. Cov khoom hnyav dua lossis loj dua yuav nyob hauv qhov chaw tsis muaj zog xws li cov raj hauv qab lossis thaj chaw nyob ruaj khov.

Kev loj hlob ntawm microbial kuj tuaj yeem tshwm sim yog tias cov khoom noj muaj nyob hauv cov txheej txheem dej. Thaum kawg, cov kab mob yuav cling rau ntawm qhov chaw thiab tsim biofilms. Cov biofilms no tsim cov txheej txheej insulating uas txo cov kev ua haujlwm ntawm cov cua sov hloov mus thiab cuam tshuam cov hydraulic tsis kam.

PTFE muaj qhov tsis tshua muaj zog saum npoo thiab ib txwm muaj qhov adhesion tsawg dua li cov xim hlau. Txawm li cas los xij, PTFE tsis tiv thaiv fouling nyob rau hauv rooj plaub thaum hydrodynamic rog tsis txaus los tiv thaiv deposition.

Qhov cuam tshuam net yog ib qho kev ua haujlwm tsis zoo ntawm thermal poob thiab qeeb qeeb hauv kev poob siab vim qhov thaiv ntawm qhov chaw sab hauv.

Tus kheej-kev coj tus cwj pwm huv thiab ntws- tus nqi pib
Flow velocity yog tus yam ntxwv tseem ceeb uas tswj hwm qhov txaus ntshai ntawm fouling hauv cov khoom siv hluav taws xob. Saum tus nqi tseem ceeb shear rog ntawm phab ntsa inhibit particle deposition thiab tshem tawm cov txheej thaum ntxov fouling tsis tu ncua.

Qhov kev ntxuav tus kheej no poob qis dua li 0.5 m / s. Qhov chaw pib no feem ntau coj los ua qhov kev txwv qis dua rau kev ua haujlwm tau zoo hauv kev xa dej huv. Hauv cov kua dej slurry lossis cov kua dej me me, qhov siab tshaj qhov tsawg tshaj plaws, feem ntau tshaj li ntawm 1.0 m / s yuav tsum tau tswj kev ncua thiab tsis txhob muaj sedimentation.

Fouling yog lub sij hawm- ywj siab thiab thim rov qab siab dua cov kev txwv no, thiab lub sij hawm- nyob ntawm thiab nyuaj rau thim rov qab hauv qab no.

Cov teebmeem ntawm Low Velocity Fouling
Cov teebmeem ntawm fouling ntawm cov dej ntws qis muaj xws li:

Insulating deposits txo cov tshav kub hloov coefficient

Cov dej ntws me me txhais tau tias kev poob siab dua

Kev faib tawm tsis sib xws hauv cov khoom siv raj

Accelerated corrosion los yog microbial induced deterioration nyob rau hauv tsis muaj zog systems

Cov teebmeem no yog cumulative, ua rau txo qis hauv kev ua haujlwm ntawm cov exchangers thiab nce qhov zaus ntawm kev saib xyuas.

Kev tsim thiab kev ua haujlwm txo qis kev xaiv
Tsawg khiav ceev kev tswj hwm ntawm fouling PTFE exchanger muaj kev sib xyaw ntawm hydraulic tsim, tshuaj tswj thiab kev tswj xyuas tsim.

Khaws Tsawg Tshaj Tawm
Ib lub hom phiaj tseem ceeb ntawm kev tsim qauv yog tswj kom muaj qhov nrawm nrawm ntawm lub raj sab kom muab tus kheej - ntxuav tes. Ib txoj cai zoo ntawm tus ntiv tes xoo yog:

Minimum tube side velocity >=0.5 m/sec (kua kua)

Tsim kev tshaj tawm nyiam tshaj lossis sib npaug li 1.0 m / s rau kev txhim kho tus kheej - ntxuav

Kev ua haujlwm ntev - lub sijhawm ua haujlwm hauv qab cov theem no yuav tsum zam rau hauv kev tsim qauv.

Optimization ntawm Tube Diameter
Qhov kev tshaj tawm rau ib qho kev txaus txaus yog cuam tshuam ncaj qha los ntawm txoj kab uas hla ntawm lub raj. Rau ib tug muab volumetric txaus, me me raj diameters ua rau siab dua velocities, nce phab ntsa shear rog thiab txo cov fouling peev xwm.

Txoj kev tsim no feem ntau ua tiav zoo dua li kev nthuav dav lub raj loj vim qhov no yuav ua rau qis qis dua thiab ua rau muaj kev pheej hmoo ntawm kev tso tawm.

Recirculation thiab Flow Control
Yog tias qhov qis qis qis yuav tsum tau ua los ntawm cov txheej txheem txwv, cov voj voog rov qab tuaj yeem ntxiv. Los ntawm kev nce hauv kev ncig hauv lub sijhawm thaum tswj cov khoom qis qis, kev tshaj tawm txaus tuaj yeem khaws cia hauv cov raj xa dej.

Qhov no feem ntau yog ua haujlwm hauv cov tshuaj rhiab heev thiab cov txheej txheem biochemical uas tsis tshua muaj kev khiav tawm tag nrho.

Tswj Tshuaj Fouling
Biological thiab scaling fouling feem ntau yog tswj los ntawm kev kho tshuaj. Cov no yog:

Biocides rau kev tswj kev loj hlob ntawm microbial

Anti-scalants los tiv thaiv cov pob zeb hauv av

Kev tu ib ntus hauv qhov chaw (CIP) cov txheej txheem

Kev tswj tshuaj lom neeg yog qhov teeb meem tseem ceeb hauv ntau daim ntawv thov kev lag luam, txawm tias qhov tsis zoo ntawm PTFE.

Cleanability Tsim
Cov exchangers yuav tsum tau tsim kom yooj yim mechanical los yog tshuaj ntxuav. Qhov no yog rau:

Ncaj raj tsim qhov twg los tau

Kev tshuaj xyuas thiab tshem tawm cov headers uas siv tau

Compatibility nrog CIP systems.

Maintainability tsim los txo downtime thiab txo lub sij hawm ntev fouling tsub zuj zuj.

Txoj Cai Kev Cai Tsim Qauv - ntawm -Phumb
Engineering cov tswv yim qhia kom txo qis fouling txaus ntshai yog:

Txhawm rau kom zoo rau tus kheej - tu tus cwj pwm yuav tsum muaj qhov tsawg kawg nkaus lub raj sab nrawm ntawm kwv yees li . 1.0 m / s.

Qhov chaw pib no muab cov npoo kev nyab xeeb uas txo qis rhiab heev rau qhov chaw thau khoom, biofilm tsim, thiab ntws maldistribution.

Xaus
Cov xwm txheej qis qis yog qhov teeb meem loj fouling rau PTFE cov khoom siv hluav taws xob vim yog qhov teeb meem ntawm qhov teeb meem thiab biofilm kev loj hlob thaum tshaj tawm qis dua qhov tseem ceeb. PTFE nto txo ​​adhesion tendencies tab sis tsis tuaj yeem them rau qhov tsis txaus hydrodynamic shear.

Kev txo qis tuaj yeem ua tau zoo yog tias kev txiav txim siab tsim qauv raug coj los siv xws li kev tswj xyuas nrawm, kev ua kom zoo ntawm cov raj, kev kho tshuaj lom neeg thiab kev tswj xyuas kev npaj. Kev tswj zoo tshaj plaws rau kev pheej hmoo fouling yog engineering tsim, tsis yog qhov tsis yog -stick zoo ntawm cov khoom.

Thaum kawg ntawm lub hnub, qhov zoo tshaj plaws tshav kub exchanger systems yog cov tsim los kom tsis txhob fouling nyob rau hauv thawj qhov chaw nyob rau hauv cov kev npaj ua hauj lwm tej yam kev mob es tsis yog cov nyob rau tom qab - fouling kev ntsuas.