Vim li cas 316 Stainless Hlau Sheath Hluav Taws Xob Hluav Taws Xob Hluav Taws Xob Hluav Taws Xob Hluav Taws Xob hauv Sodium Hypochlorite Disinfection Loops ntawm 30-50℃Tsim Kev Tawm Tsam Sib Nrauj ntawm Peb -Theem Ciam Hauv 200 Teev Kev Pabcuam Sib Tham?

Sodium hypochlorite (NaOCl) feem ntau yog siv rau kev tua kab mob hauv kev kho dej hauv nroog, kev huv ntawm kev ua zaub mov thiab tshuaj CIP (huv-hauv- qhov chaw)). Hluav taws xob cua sov raj feem ntau yog siv nyob rau hauv hypochlorite recirculation loops kom daws tau qhov kub thiab txias nyob rau hauv thaj tsam ntawm 30-50℃rau optimum tshuaj tua kab mob efficiency. Kev ua tsis tiav ntawm ntau lub chaw kho dej, txawm li cas los xij, tau pom tias 316 stainless hlau sheaths muaj kev cuam tshuam rau qhov chaw hauv cheeb tsam, qhov hnyav hnyav ntawm huab cua -kua- vapor peb - theem ciam teb nyob rau hauv 200 mus rau 500 teev ntawm kev pabcuam cuam tshuam. Qhov kev tawm tsam no tsis pom nyob rau hauv cov dej tsis tu ncua lossis qhuav qhuav. Qhov peb ntawm -theem ciam teb, qhov twg cov sheath tawm hauv cov tshuaj hypochlorite thiab nkag mus rau qhov chaw vapor saum toj no, raug rau kev sib xyaw ua ke ntawm cov xwm txheej xws li ntub dej thiab ziab, oxygen enrichment los ntawm kev sib cuag nrog huab cua, evaporation ntawm hypochlorite thiab chloride hom ua rau concentration, thiab decomposition ntawm hypochlorite rau chlorine gas (Cl2). Qhov tshwm sim yog nws tus kheej- txhawb nqa corrosion ntawm tes uas txiav ib lub voj voog ncig mus rau hauv lub plhaub ntawm cov kua dej, feem ntau permeating phab ntsa tag nrho hauv lub lis piam. Txoj kev tshawb no ntsuas qhov grooving corrosion tus nqi ntawm peb -theem ciam teb nyob rau hauv NaOCl kev pabcuam thiab nthuav tawm cov qauv tsim thiab kev pom zoo ua haujlwm kom tsis txhob muaj qhov ua tsis tiav no.

Electrochemistry ntawm Peb -Phase Boundary hauv Solutions ntawm Hypochlorites
Sodium hypochlorite cov ntsiab lus yog inherently unstable thiab decompose raws li 3NaOCl → 2NaCl + NaClO3 thiab kuj 2NaOCl → 2NaCl + O2. Decomposition yog ceev nyob ib ncig ntawm 30-50oC. Cov zaj duab xis nyias ntawm cov tshuaj hypochlorite wetting lub sheath saum toj ntawm cov kua ntau theem ntawm peb -theem ciam teb (cua{12}}kua-sheath) sai sai evaporates, concentrating hypochlorite los ntawm ib txwm 0.5-2.0% siv tau chlorine kom siab li 10-15% nyob rau hauv evaporating zaj duab xis. Cov concentrated hypochlorite decomposes sai dua kom tawm tau cov roj chlorine (Cl₂) uas yog corrosive heev rau 316 stainless hlau thiab ib cheeb tsam oxidising, tsis tshua muaj pH ib puag ncig. Nyob rau tib lub sijhawm, lub voj voog ntub dej thiab ziab kom tsis txhob tsim cov yeeb yaj kiab ruaj khov. Thaum lub sij hawm qhuav ntawm lub voj voog ib zaj duab xis passive uas tau tsim tau qhuav thiab tawg. Thaum lub sij hawm rewetting tshiab hypochlorite ua phem rau cov hlau raug ua ntej txheej tshiab tuaj yeem tsim.

Kev tsim ntawm lub xov tooj sib txawv aeration nrawm nrawm lub grooving mechanism Qhov cheeb tsam hauv qab cov kab ua kua yog oxygen-depleted (vim hypochlorite breakdown siv oxygen) whereas txheej nyias saum peb - theem ciam teb yog oxygen- nplua nuj los ntawm kev sib cuag nrog huab cua. Qhov chaw nplua nuj oxygen ua cathodic thiab cov hlau hauv qab no ua anodic. Lub anodic tam sim no nyob rau hauv cov kua kab thiab tsim ib tug sib sib zog nqus groove nyob rau hauv lub sij hawm.

Quantifying grooving corrosion tus nqi ntawm peb -theem ciam teb
316 stainless hlau sheath qauv (1.5 hli phab ntsa, 12 hli OD, tov-annealed) tau ib nrab rau hauv 1.0% muaj cov tshuaj chlorine NaOCl (pib pH 10.5) ntawm 40℃hauv kev soj ntsuam, nrog cov kua theem ntawm nruab nrab -ntev. Qhov kev sim hloov pauv ntawm cov cua sov (lub tsho muaj zog rau 50℃qhov kub thiab txias) thiab idling (tsis muaj cua sov, 40℃da dej) ntawm 6-teev rau / 6-teev tawm lub voj voog. Nyob rau lub sijhawm, cov qauv raug kuaj xyuas qhov tob ntawm qhov qub kua. Groove qhov tob tau soj ntsuam los ntawm kev sib cais thiab kho qhov muag microscopy.

Lub Sijhawm Tawm (teev) Tus naj npawb ntawm ntub- Lub voj voog qhuav (6 hr txhua) Qhov tob Max (μm) Qhov dav dav (mm) Phab ntsa Thickness txo ntawm qhov zawj (ntawm 1.5mm)
0 0 0 0 0% 100 8 (kwv yees) 45 0.8 3% 200 17 110 1.2 7% 300 25 210 1.5 14% 400 33 380 2.0 25% 500 42 620 2.5 41% (ze perforation)
600 50 880 (perforated) 3.0 59%
Tus nqi grooving yog kwv yees li 1.5-2.0 um / h ntawm qhov raug, zoo ib yam tom qab pib incubation ntawm 50-100 teev. Rau 1.5 hli phab ntsa, lub sij hawm npaj rau perforation yog 600-800 teev (25-33 hnub) nyob rau hauv kev nruam cycling. Hauv kev ua haujlwm nrog kev ncua sij hawm tawm mus thiab sib txawv, tsis ua haujlwm ntau zaus hauv 200-500 teev (8-21 hnub).

Kev sib piv rau Nruam Nruam Nruam thiab Lwm Yam
Kev tswj xyuas tau ua rau cais peb - theem ciam teb cuam tshuam nyob rau hauv ntau yam xwm txheej. Cov txheeb cais hauv qab no qhia tau hais tias tsis muaj kev puas tsuaj rau peb theem ciam teb piv rau kev tso dej tsis tu ncua (tsis muaj ntub dej- caij tsheb kauj vab qhuav) thiab qhuav tag.

Test Condition NaOCl Concentration (% muaj Cl 2) Temperature (degree) Exposure Time (teev) Maximum Corrosion Depth (μm) Surface Condition
Siab raus dej (tsis muaj huab cua interface) 1.0 40 500 25 Me me pitting, uniform
Ua kom tiav 1.0 50 (cov ntaub rhuab) 500 45 Pitting, tsis muaj grooving
Ib nrab raus dej, theem ua kua tsis tu ncua (tsis muaj kev caij tsheb kauj vab) 1.0 40 500 180 (ntawm cov kab ua kua) Grooving, tsawg dua
Ib nrab rau hauv dej, ntub- caij tsheb kauj vab qhuav ( cua sov rau / tawm) 1.0 40/50 500 620 Sib sib zog nqus grooving
Ib nrab immersed, pH tswj rau 9.5 (raws li sodium carbonate) 1.0 40/50 500 85 Lub teeb grooving
Ib nrab raus dej, nitrogen tshem tawm tshaj qhov chaw vapor 1.0 40/50 500 110 Txo grooving
Ib nrab raus dej, deionised dej (tsis muaj NaOCl) 0 40/50 500 0 Tsis muaj corrosion
Cov yam tseem ceeb tseem ceeb yog muaj cov tshuaj hypochlorite, muaj cov kua -vapor interface, ntub- caij tsheb kauj vab qhuav, thiab nkag tau oxygen mus rau qhov chaw vapor. Tshem tawm ib qho ntawm cov xwm txheej no txo ​​qis qhov sib piv ntawm 3-7.

Cov nyhuv ntawm cov tshuaj rau qhov Grooving Rate
Tus nqi ntawm grooving yog rhiab heev rau cov tshuaj chlorine concentration ntawm cov tshuaj hypochlorite. Cov concentrations ntau dua ua rau kom nrawm dua ntawm hypochlorite, nce cov roj chlorine ntau lawm, thiab ntau dua evaporative concentration. Kev ntsuam xyuas ntawm 40℃tas li nrog 6- teev ntub-qhuav cycles thiab 500 teev tag nrho raug cuam tshuam ua rau muaj kev sib raug zoo hauv qab no:

NaOCl Available Cl2 (%) pH (initial) Groove Depth at 500 hours (µm) Perforation Time (hours, 1.5 mm wall) Vapour Space Cl2 Odour Observed 0.1 10.0 45 >5000 (tsis tiav) Tsis muaj 0.5 10.3 180 2500 Me 1.0 10.5 620 600-800 Muaj zog 2.0 11.0 1050 (perforated < 500 teev) 300-400 Muaj zog heev
1.0 nrog chlorine scavenger (thiosulphate, 10 ppm) 10.5 85 2800 Tsis yog
Lub sijhawm kwv yees perforation rau grooving nyob rau hauv ib txwm haus dej tua kab mob loops nrog 0.5-1.5 % NaOCl yog 2-8 lub lis piam rau 316 sheaths. Lub xub ntiag ntawm thiosulphate zoo siv cov tshuaj dawb chlorine thiab tsis txhob grooving tab sis yuav txo tau cov tshuaj tua kab mob.

Piv txwv ntawm kev ua tsis tiav hauv cov chaw kho dej
Kev tshuaj xyuas ntawm 23 lub chaw kho dej hauv nroog siv 316 stainless hlau encased cua sov hauv NaOCl recirculation loops (0.5-1.2% muaj Cl₂, 35-45 degree, sib cuam tshuam twj tso kua mis ua haujlwm nrog ntub- voj voog qhuav txhua 4-12 teev) pom cov qauv ua tsis tiav hauv qab no:

Lub Chaw Ua Haujlwm Tus Qauv Ua Haujlwm kwv yees li ntub dej- Lub voj voog qhuav ib hnub Groove Puncture Lub Sijhawm tau txhais
Nroj tsuag A (1.2 % NaOCl) Kev rov ua haujlwm tsis tu ncua, theem tas li 0 (tsis muaj kev caij tsheb kauj vab) 8-12 lub hlis (tsis muaj groove, pitting nkaus xwb)
Nroj tsuag B (1.0% NaOCl) Sib Nqus, 6 hr ntawm / 6 hr tawm, qib sib txawv 2 18 d
Nroj tsuag C (0.8% NaOCl) Nquag, 8 teev rau / 16 teev tawm, theem hloov pauv 1.5 25 hnub
Cog D (0.5% NaOCl) Sib Nqus, twj tso kua mis txhua 4 teev, theem qis ntawm cov voj voog 6 12 hnub
Nroj tsuag E (0.5% NaOCl, qib kua tswj los ntawm ntab valve) Cov cua sov tsis sib xws, tab sis tsis muaj qib kev caij tsheb kauj vab 0 (tsis muaj qib hloov) 6 lub hlis (tsis muaj zawj)
Nroj tsuag A thiab E qhia tias ua kom muaj cov kua dej ruaj khov (tsis ntub - kev caij tsheb kauj vab qhuav ntawm lub plhaub) yog qhov tseem ceeb tshaj qhov muaj cov tshuaj hypochlorite siab hauv kev tiv thaiv grooving. Concentration tsis cuam tshuam rau tus nqi ntawm qhov tsis ua haujlwm ntawm cov nroj tsuag uas muaj theem hloov pauv lossis kev ua haujlwm batch uas lub rhaub tau raug thaum lub voj voog ntws.

Tsim thiab kev ua haujlwm zoo los tiv thaiv peb -Theem Grooving
Peb qhov kev daws teeb meem engineering tau ua haujlwm los txo qis lossis txo qis qis peb -theem grooving hauv NaOCl kev pabcuam. Txoj hauv kev zoo tshaj plaws yog khaws lub rhaub kom huv hauv qab dej txhua lub sijhawm. Tsim lub tank los yog lub voj nrog qhov tsawg kawg nkaus ua kua theem saum toj kawg nkaus ntawm cov khoom cua sov. Muab qhov hloov pauv qis qis uas de- ua kom lub zog ntawm lub tshuab cua sov thaum cov kua qib poob qis hauv qab lub plhaub sab saum toj.

Qhov thib ob yog ua kom cov kua dej nyob rau hauv ib qho kev tsis sib xws ntawm kev ua haujlwm ntawm cov twj tso kua mis lossis lub tshuab cua sov, yog li zam kom tsis txhob ntub dej - caij tsheb kauj vab qhuav thaum tsis muaj kua txaus los ua kom tag nrho submerged. Ib qho dej ntws tsis tu ncua los yog qib tswj lub valve nres cov kua dej los ntawm kev mus los ntawm qhov chaw sheath.

Qhov thib peb txoj hauv kev yog rau cov kab ke thaum qhov kev hloov pauv tsis tuaj yeem tiv thaiv. Kab rov tav installation ntawm lub rhaub, tsis ntsug. Thaum lub raj yog kab rov tav, peb - theem ciam teb tsuas yog ib kab nyob rau sab saum toj ntawm lub raj tsis yog tag nrho lub voj voog. Tsis tas li ntawd qhov zawj tsim nyob rau sab saum toj tsis ncav cuag lub siab ciam teb sai li sai tau. Tsis tas li ntawd, lub raj kab rov tav tuaj yeem ua tau nrog cov khoom cua sov nyob rau hauv qab, kom lub sab saum toj ntawm lub sheath tsis ncaj qha rhuab, yog li txo qis hauv zos kub ntawm peb -theem ciam teb.

Hloov rau Hypochlorite Service
Yog tias yuav tsum tau 316 stainless hlau, tab sis peb theem tsis tuaj yeem raug zam, tom qab ntawd kev kho dua tshiab cov ntaub qhwv muaj qee qhov zoo dua. Tsis muaj cov hlau tsis zoo uas tiv taus tiag tiag rau peb theem hypochlorite mob.

Sheath Material Groove Depth ntawm 500 teev, 1% NaOCl, 40℃, ntub -kev caij tsheb kauj vab qhuav (um) Tus nqi txheeb ze (piv rau 316) Pom zoo
316 Stainless Hlau 620 1.0 Tsis muaj (ua tsis tau sai)
904L (UNS N08904) 280 2.5 Ciam teb
Alloy 825 (UNS N08825) 120 4.0 Txais nrog kev tswj ntawm qib
Titanium Qib 2<10 2.2 Yes (very good)
Titanium Qib 7<5 2.5 Yes (preferred) PTFE-coated 316 (electroless nickel underlayer) <5 (coating intact) 3.0 Yes, but danger of coating deterioration
Titanium Qib 2 lossis Qib 7 yog resistant rau hypochlorite nres ntawm qhov kub txog li 70℃thiab yog passive txawm nyob rau hauv peb theem xwm txheej. Cov ntaub ntawv teb los ntawm cov chaw ua zaub mov uas 316 sheaths tau hloov nrog titanium qib 2 hauv 0.8% NaOCl CIP voj tsis pom qhov grooving lossis pitting tom qab 24 lub hlis ntawm kev ua haujlwm tsis sib xws uas 316 sheaths yav dhau los ua tsis tiav txhua 3-4 lub lis piam.

Hypochlorite Loop Heater Specification Language
Hauv kev yuav khoom hluav taws xob cua sov tub rau kev pabcuam sodium hypochlorite qhov twg muaj peev xwm ua rau ntub - lub voj voog qhuav lossis theem hloov pauv, cov kws ua haujlwm yuav tsum xav tau titanium Qib 2 lossis Qib 7 cov ntaub ntawv sheath raws li qhov tsawg kawg nkaus. Qhov twg 316 stainless hlau siv nyob rau hauv ib qho system uas twb muaj lawm, cov kev khiav hauj lwm hauv qab no yuav tsum tau muab tso ua ke: (a) Cov qib ua kua yuav tsum tau khaws cia saum toj kawg nkaus cua sov lub sij hawm txhua lub sij hawm los ntawm ib theem tswj system; (b) Ib qho qis- theem txiav tawm yuav tsum tau muab, cuam tshuam nrog lub tshuab hluav taws xob tiv thaiv kom de- ua kom lub zog ntawm lub rhaub yog tias qib poob qis dua qhov kev nyab xeeb yam tsawg kawg nkaus; (c) Lub kaw lus yuav tsum raug tsim los rau kev ua haujlwm tas mus li tsis tu ncua es tsis yog rau cov dej ntws tawm batch-thiab- ua haujlwm; (d) Lub sheath yuav tsum tau soj ntsuam ntawm cov kua theem txhua hli rau grooving los ntawm ultrasonic thickness ntsuas los yog kev soj ntsuam pom los ntawm ib tug pom iav. Rau kev txhim kho tshiab nrog cov ntsiab lus hypochlorite tshaj 0.2% muaj Cl 2 thiab kub tshaj 35 degree, qhia titanium Qib 7 sheath khoom thiab kab rov tav cua sov taw qhia. Peb theem ciam teb nyob rau hauv cov kev pab cuam hypochlorite nthuav tawm qhov tshwj xeeb aggressive micro-ib puag ncig uas yog qhov sib txawv los ntawm tag nrho immersion los yog vapor theem raug. Engineers uas nkag siab qhov no tuaj yeem xaiv cov ntaub ntawv tsim nyog thiab kev tsim qauv kom tsis txhob muaj qhov tsis ua haujlwm sai uas ua rau daim ntawv thov no.