Hauv kev lag luam tshuaj thiab fluorine-txog kev lag luam,electromagnetic flowmetersyog dav siv rau cov xov xwm conductive vim lawv cov neeg siab thiab tsis tshua muaj siab poob. Txawm li cas los xij, thaum cuam tshuam nrog fluorine- muaj cov xov xwm, tshwj xeeb tshaj yog cov kab ke uas muaj cov tshuaj fluoride ions (F⁻) lossis hydrofluoric acid (HF), kev xaiv cov khoom siv hluav taws xob tsis zoo tuaj yeem ua rau corrosion sai, teeb liab tsis ruaj khov, lossis txawm tias muaj kev puas tsuaj loj.
Tsis zoo li cov ntawv thov ib txwm siv, fluorine chemistry qhia txog cov tshuaj tiv thaiv electrochemical thiab cov khoom sib tw sib tw. Yog li ntawd, qhov sib txawv ntawm F⁻ systems thiab HF systems, nrog rau cov txheej txheem xaiv cov khoom siv, yog qhov tseem ceeb los xyuas kom meej ntev - lub sij hawm ntseeg tau thiab ntsuas qhov tseeb.
Engineering Selection Decision Guide Guide
1. F⁻ System (Tsis pub dawb HF)
|
F⁻ Concentration |
Qhov kub thiab txias |
Khoom siv pom zoo |
Lub neej vam meej* |
|
<100 ppm |
<80°C |
316L |
2-3 xyoos |
|
100-500 ppm |
<100°C |
C-276 |
3-5 xyoos |
|
500-5000 ppm |
<120°C |
Gr.2 Titanium |
2-4 xyoos |
|
500-5000 ppm |
<120°C |
WC (Ni binder) |
4-6 xyoo |
|
>5000 ppm |
<150°C |
WC (Ni binder) |
3-5 xyoos |
|
>5000 ppm |
>150 degree |
Pt-Ir lossis Ceramic |
5–8 xyoo |
* Cia siab rau lub neej raws li cov txheej txheem tshuaj lom neeg; cuam tshuam loj heev los ntawm pH, ntws nrawm, thiab impurities
** Oxidizing condition guarantee yuav tsum tau
2. HF System (muaj Hydrofluoric Acid)
|
HF Concentration |
Kub |
Khoom siv pom zoo |
Cov ntaub ntawv txwv |
Yuav tsum tau foob |
|
<1% |
<60°C |
Hastelloy B |
C-276, 316L |
Txheem FKM |
|
1–5% |
<80°C |
Hastelloy B |
C-276, Titanium |
FFKM |
|
5–20% |
<100°C |
Pt-Ir |
Tantalum, Titanium, 316L, C-276 |
PTFE foob foob |
|
>20% or>100 degree |
Ib qho |
Ceramic electrode los yog cais ntsuas |
Tag nrho cov khoom siv hlau- |
Dual foob + kev saib xyuas dej |
Qhov tseem ceeb Distinction:Hastelloy B (Ni-Mo based, resists txo acids) vs. Hastelloy C (Ni-Cr-Mo based, resists oxidizing acids). HF yog ib puag ncig uas tsis yog -oxidizing acid (feem ntau txo cov mob). Kev siv C-276 tsis tu ncua yog qhov ua rau tsis ua haujlwm ntawm qhov chaw.
Cov xwm txheej xaiv tsis raug
Case 1: C-276 Siv rau 10% HF Cov dej khib nyiab
Qhov tshwm sim:Electrode perforation tom qab 45 hnub, nruab nrab to
Ua rau:Mistook HF system rau F⁻ system; tsis meej pem thaj tsam ntawm Hastelloy B/C
Qhov tshwm sim:3-hnub kev tsim khoom nres, poob ntawm kwv yees li . 120,000 CNY
Case 2: Tantalum Electrode Siv rau 15% HF hauv Kev Lag Luam Photovoltaic
Qhov tshwm sim:Pitting hnyav ntawm electrode nto tom qab 30 hnub, teeb liab drift ntawm 8%
Ua rau:Tso siab rau cov ntaub ntawv tsis tu ncua uas "tantalum resists tag nrho cov acids muaj zog"; ignored HF complexation
Qhov tshwm sim:Batch scrapping vim cov txheej txheem 失控, poob ntawm approx . 250,000 CNY
Case 3: WC siv rau High Fluorine + High Precision Metering
Qhov tshwm sim:Flow indication deviation ntawm 12% tom qab 60 hnub, tsis muaj tswb tshwm sim
Ua rau:Tsom tsuas yog rau cov neeg kho tshuab corrosion kuj; ignored tej zaum drift los ntawm binder theem dissolution
Qhov tshwm sim:Raw khoom overconsumption vim metering yuam kev, poob ib hlis approx . 80,000 CNY
Common Lessons:Kev ua tsis tiav hauv fluorine- muaj cov xwm txheej feem ntau tsis yog "cov khoom siv tsis zoo txaus," tab sis tsis yog qhov nruab nrab tus cwj pwm tsis raug lossis tsis saib xyuas cov khoom ciam teb rau qhov tsis yog -oxidizing acid ib puag ncig (feem ntau txo cov xwm txheej).
Cov ntsiab lus
Electrode xaiv rau fluorine- muaj cov xwm txheej nyob rau ntawm qhov sib txawv ntawm F⁻ thiab HF chemical ib puag ncig (suav nrog kev txiav txim siab pH) thiab nkag siab tias cov khoom tsis ua haujlwm suav nrog tsis yog "corrosion perforation" nkaus xwb tab sis tseem zais cov txheej txheem xws li electrochemical muaj peev xwm drift thiab crevice corrosion.
Cov ntsiab cai tseem ceeb ntawm kev txiav txim siab:
- Rau cov xwm txheej HF,Tsis txhob sivC-276, tantalum, lossis titanium. Ua ntej Hastelloy B (tsis muaj concentration) lossis Pt-Ir (siab concentration).
- Rau WC electrodes, tsim kom muaj peev xwm saib xyuas cov txheej txheem ntau dua li tsuas yog tso siab rau kev tshuaj xyuas qhov muag.
- For high-temperature HF (>100°C) or ultra-high concentration (>20%), xav txog ceramic electrodes lossis tsis yog -kev ntsuas kev ntsuas.
- Seal materials must match the HF concentration; FPM/Viton fails rapidly in >20% HF.
Hauv tiag - ntiaj teb daim ntawv thov, kev ntseeg tau ntawmelectromagnetic flowmetersnyob rau hauv fluorine- muaj ib puag ncig yog txiav txim siab tsis yog los ntawm kev xaiv cov khoom, tab sis los ntawm kev nkag siab zoo ntawm cov txheej txheem, cov yam ntxwv ntawm cov tshuaj, thiab ntev - lub sij hawm ua haujlwm txaus ntshai.
Lub tswv yim xaiv ua tiav tau dhau mus dhau ntawm cov ntaub ntawv - nws yuav tsum muaj kev sib koom ua ke nruab nrab ntawm kev txheeb xyuas, txwv cov khoom siv, thiab kev saib xyuas cov txheej txheem rau hauv lub hauv paus kev txiav txim siab. Los ntawm kev ua li ntawd, engineers tuaj yeem tiv thaiv kev ua tsis tiav ntxov ntxov, zam qhov kev ntsuas zais zais, thiab txo cov nqi ntawm lub neej.
Rau cov haujlwm uas cuam tshuam nrog cov xov xwm fluorine aggressive lossis cov teeb meem kev ntsuas rov tshwm sim, thaum ntxov -thev naus laus zis thev naus laus zis thiab kev txhawb nqa kev xaiv tau raug pom zoo kom ua kom cov txheej txheem kev nyab xeeb thiab kev ntsuas kev ncaj ncees.
Kev pom zoo:Tsim kom muaj peb - qhov kev xaiv qhov kev xav ntawm [Medium – Material – Monitoring] kom tsis txhob cia siab rau cov ntaub ntawv tiv thaiv corrosion nkaus xwb.
Yog tias koj tab tom ntsib cov electrode tsis tu ncua, teeb liab drift, lossis muaj kev xaiv nyuaj rau cov xwm txheej hnyav ntawm -site, thov muab cov kev ntsuas nruab nrab (concentration/temperature/pH/oxidants/solid content), thiab peb tuaj yeem pab xaiv cov kev daws teeb meem.
