Efflorescence nyob rau hauv industrial kilns (tshwj xeeb tshaj yog fluidized txaj boilers, khib nyiab incinerators, cement kilns, thiab lwm yam) yog ib qho kev phom sij zoo. Nws tshwm sim raws li dawb los yog greyish -dawb hmoov deposits nyob rau saum npoo, qee zaum nrog sandblasting, pulverization, thiab tev. Qhov no tsis tsuas yog cuam tshuam rau cov tsos ntawm cov castable tab sis kuj txo nws cov hnav tsis kam, thermal shock resistance, thiab corrosion resistance, shortening nws cov kev pab cuam lub neej thiab txawm ua rau muaj kev ruaj ntseg teeb meem xws li kiln cua to thiab localized overheating. Ntau tus kws kho mob, thaum ntsib efflorescence, yooj yim poob rau hauv qhov kev xav tsis zoo ntawm "tsuas yog kho qhov chaw tsis hais txog lub hauv paus ua rau," ua rau rov tshwm sim efflorescence. Niaj hnub no, peb yuav piav qhia meej txog cov laj thawj tseem ceeb ntawm efflorescence hauvrefractory castables, cov txheej txheem kev txheeb xyuas sai, thiab siv ncaj qha rau kev tiv thaiv thiab kho kev ntsuas los pab koj kom tsis txhob muaj kev saib xyuas thiab kev siv pitfalls.
Lub ntsiab ntawm efflorescence nyob rau hauv cov khoom refractory castables yog tshwm sim los ntawm kev sib xyaw ua ke ntawm alkali hlau ions, ya raws, thiab kev tsiv teb tsaws. Ntawm cov xwm txheej no, lub hauv paus ntawm alkali hlau ions yog qhov ua rau sab hauv, thaum ya raws thiab kev tsiv teb tsaws yog sab nraud; tag nrho peb yog qhov tseem ceeb. Tshwj xeeb:
I. Internal Cause: Alkali Hlau Ions muaj nyob rau hauv Castable Refractories
Qhov no yog qhov laj thawj tseem ceeb rau alkali reversion. Alkali hlau ions feem ntau yog los ntawm peb yam, uas tseem yog qhov yooj yim tshaj plaws saib xyuas:
1. Taw qhia los ntawm Raw Materials: Yog hais tias cov aggregates (xws li siab - alumina aggregates, corundum aggregates) thiab hmoov (xws li silica fume, alumina hmoov) nyob rau hauv cov castable refractories tsis huv txaus, lawv yuav muaj me me ntawm alkali hlau impurities (O, xws li silica fume, alumina hmoov). thiab cov ntsiab lus ntawm alkali hlau nyob rau hauv cov binders siv tej zaum yuav tshaj tus qauv (cov specification yuav tsum tau kom cov Na₂O + K₂O cov ntsiab lus nyob rau hauv lub binder yuav tsawg dua los yog sib npaug rau 0.6%).
2. Qhia los ntawm Additives: Qee cov tshuaj additives ntxiv rau castable refractories, xws li dej-txo cov neeg ua hauj lwm, retarders, thiab accelerators, yog alkaline formulations. Yog tias qhov kev xaiv tsis tsim nyog lossis tus nqi ntxiv yog ntau dhau, nws yuav ua rau cov ntsiab lus ntawm alkali hlau ion nyob rau hauv lub system.
3. Taw qhia los ntawm Kev Sib Tw Dej: Cov kais dej los yog cov dej muaj dej siv thaum lub sij hawm sib xyaw ntawm cov castables, yog alkaline (pH> 8.5) lossis muaj cov ntsev alkali hlau soluble, yuav qhia ncaj qha alkali ions rau hauv castable.
II. Sab nraud Factor 1: Cov dej noo ntau dhau + Cov av noo ntau dhau hauv qhov chaw kho kom zoo
Moisture ua raws li "carrier" rau kev tsiv teb tsaws ntawm alkali hlau ions. Yog tsis muaj dej noo, alkali ions tsis tuaj yeem txav los ntawm sab hauv ntawm lub castable mus rau saum npoo, thiab alkali rov qab tsis tuaj yeem tshwm sim.
1. Cov dej ntau dhau thaum sib tov: Thaum lub sij hawm tsim kho, txhawm rau txhawm rau txhawm rau txhawm rau thiab kev co, cov dej ntau dhau yog ntxiv rau qhov muag tsis pom kev, ua rau cov dej dawb ntau dhau hauv cov castable. Cov dej dawb no dissolves cov alkali hlau ions sab hauv, tsim cov tshuaj alkaline.
2. Humid Curing Ib puag ncig: Thaum lub sij hawm kho cov theem ntawm cov castable, yog tias cov av noo nyob ib puag ncig siab dhau (kwv yees cov av noo> 85%), qhov cua tsis zoo, lossis nws raug ncaj qha los nag lossis daus, cov av noo noo evaporates maj mam, thiab cov tshuaj alkaline sab hauv yuav txuas ntxiv mus rau saum npoo. Tom qab cov dej evaporates, alkali ions yuav precipitate rau saum npoo.
3. Tom qab Moisture Intrusion: Nyob rau hauv thawj theem ntawm kiln ua hauj lwm, yog hais tias lub kiln lub cev tsis zoo kaw, sab nraud los nag thiab condensate tuaj yeem nkag mus rau hauv cov castable, reactivating alkali ions thiab ua rau rov qab alkali.
III. Sab nraud Factor 2: Txuas Pores hauv Castable
Qhov sib txuas pores hauv refractory castables yog cov "channels" los ntawm cov kev daws teeb meem alkaline tsiv los ntawm sab hauv mus rau saum npoo. Qhov pores ntau dua thiab zoo dua qhov kev sib txuas, qhov hnyav dua qhov alkali rov tshwm sim.
1. Kev tsim kho tsis zoo: Kev sib cog lus tsis txaus thiab kev kho tsis txaus ua rau xoob xoob thiab micro- tawg hauv cov castable, tsim kev sib txuas "channels";
2. Improper Material Proportioning: Unreasonable aggregate and powder gradation, or insufficient binder, result in low density and excessively high porosity in the castable (the specification requires a castable porosity<=20%).
Kev Tiv Thaiv Kev Ntsuas rau Efflorescence + Txoj Kev Kho Kom Zoo Rau Cov Efflorescence Lub hauv paus ntsiab lus ntawm kev tuav cov efflorescence yog: kev tiv thaiv ua ntej, kho qhov thib ob - tswj qhov chaw ntawm alkali ions, txo cov dej noo, thiab txo cov porosity ua ntej tuaj yeem tiv thaiv efflorescence los ntawm cov hauv paus hniav; Yog tias efflorescence tau tshwm sim lawm, kev sib xyaw ua ke ntawm "nto tu + sab hauv" yuav tsum tau saws raws li qhov hnyav los tiv thaiv qhov teeb meem tsis zoo.
I. Kev Tiv Thaiv
1. nruj me ntsis tswj qhov zoo ntawm raw khoom:
1) Xaiv qis-alkali raw cov ntaub ntawv: Ua ntej siv cov siab- purity aggregates (Al₂O₃ Ntau dua lossis sib npaug li 85%) thiab qis-alkali binders (xws liqis -alkali phosphate cement, low-alkali silica fume), xav kom Na₂O + K₂O cov ntsiab lus hauv cov ntaub ntawv raw tsawg dua lossis sib npaug li 0.6%;
2) Kev tshuaj ntsuam ntxiv: Xaiv cov dej nruab nrab lossis tsis muaj zog acidic - txo cov neeg ua haujlwm thiab cov retarders, tsis txhob siv cov tshuaj alkaline ntxiv, thiab tswj cov nyiaj ntxiv raws li cov chaw tsim khoom cov lus qhia (feem ntau tsis pub tshaj 0.5%);
3) Tswj cov dej sib xyaw: Siv cov dej nruab nrab (pH tus nqi 7-8.5), tsis txhob siv cov dej khib nyiab alkaline lossis dej ntsev rau kev sib xyaw.
2. Txhim kho kev tsim kho thiab kho cov txheej txheem:
1) Kev Tswj Xyuas Dej Ntxiv: Ntxiv dej raws li qhov sib xyaw ua ke muab los ntawm cov chaw tsim khoom castable. Qhov muag tsis pom kev ntxiv dej yog txwv tsis pub. High- dej ua haujlwm tau zoo- txo cov neeg ua haujlwm tuaj yeem ntxiv los txhim kho cov dej ntws ntawm cov castable, hloov qhov xav tau dej ntxiv.
2) Xyuas kom Compaction: Siv lub immersion vibrator kom compact refractory castable kom txog rau thaum lub nto yog du thiab tsis muaj huab cua npuas. Tsis txhob nyob rau hauv - kev co thiab dhau - kev vibration kom txo cov porosity sab hauv.
3) Standardize lub Curing Ib puag ncig:
Tswj qhov kub ntawm qhov kub ntawm 15-25℃thiab qhov txheeb ze humidity ntawm 60% -80%. Khaws qhov cua kom zoo thiab tsis txhob ntub, nyob ib puag ncig. Lub sijhawm kho yuav tsum tsis pub tsawg tshaj 72 teev. Nyob rau hauv cov huab cua kub, dej yuav tsum tau txau kom tswj tau cov dej noo, tab sis cov dej yuav tsum tau zam.
II. Txoj kev kho mob rau Existing Efflorescence
1. Lub paj me me
(tsuas yog me me ntawm cov hmoov dawb ntawm qhov chaw, tsis muaj xuab zeb lossis hmoov av)
1) Kev Tu Nto: Ua tib zoo ntxuav cov hmoov dawb los ntawm qhov chaw nrog txhuam kom qhuav thiab cov cua compressed (tsis txhob yaug nrog dej kom tsis txhob nqa cov dej noo rov qab rau sab hauv);
2) Cov dej noo- pov thawj Sealing: Tom qab ntxuav, siv ib txheej ntawm qis-alkali sealant (xws li silane sealant), thov sib npaug los tsim cov txheej tiv thaiv kom tsis txhob ya raws;
3) Environmental Control: Txhim kho qhov cua nyob ib puag ncig ntawm lub qhov cub, tsis txhob muaj qhov chaw ntub dej, thiab tiv thaiv cov dej nag los ntawm kev ntxuav ncaj qha rau saum npoo ntawm cov castable.
2. Nruab nrab efflorescence
1) Kev tu lub ntsej muag: Maj mam tshem cov xuab zeb thiab xoob ntawm qhov chaw uas siv lub scraper thiab lub kaum sab xis grinder (tsis txhob ua kom cov qauv ntom ntom), tom qab ntawd ntxuav nrog cua compressed;
2) Kev kho deg: Kho qhov chaw tshem tawm nrog qis -alkali refractory castables, compact nws, thiab tom qab ntawd kho raws li qhov tshwj xeeb (kho lub sij hawm tsis pub tsawg tshaj 48 teev);
3) Kev sib khi thiab kev tiv thaiv: Tom qab kho, siv ob lub tsho uas tsis tshua muaj -alkali sealant los txhim kho qhov dej tsis zoo thiab alkali{2}} cov khoom tiv thaiv.
3. Kev mob hnyav heev
1) Kev tshem tawm kom tiav: Tshem tawm tag nrho cov efflorescent hnyav thiab cov txheej txheem xoob kom txog rau thaum txheej txheej tuab, tawv tawv raug nthuav tawm. Ntxuav qhov chaw ntawm cov plua plav thiab cov khib nyiab.
2) Recasting: Siv qis-alkali, siab- ntom ntom castable, sib tov, ncuav, thiab vibrate raws li cov lus qhia los xyuas kom meej compaction.
3) Txhim kho Curing: Tom qab nchuav, ua raws li cov txheej txheem kho (kub 15-}25 degree, av noo 60%-80%, lub sijhawm kho tsis tsawg dua 72 teev). Thaum kho, tsis txhob cuam tshuam thiab ya raws . 4) Kev Tiv Thaiv Kev Kho Mob Tom Qab: Tom qab kho, siv cov tshuaj nplaum qis-alkali. Nyob rau tib lub sijhawm, tshawb xyuas lub qhov cub tawg thiab kho cov dej ntws los tiv thaiv kev nkag mus rau yav tom ntej.
Efflorescence nyob rau hauv refractory castables yuav zoo li "qhov teeb meem me," tab sis nws yog qhov tshwm sim ntawm kev sib koom tes tsis raug hauv ntau theem, suav nrog cov khoom siv raw, kev tsim kho, thiab kho. Yuav kom daws tau qhov teeb meem ntawm efflorescence tag nrho, qhov tseem ceeb yog qhov tseem ceeb ntawm kev tiv thaiv los ntawm kev tswj hwm nruj ntawm cov khoom siv raw thiab cov qauv kev tsim kho thiab kev saib xyuas. Yog tias efflorescence twb tshwm sim lawm, kev kho mob yuav tsum tau kho kom haum rau qhov hnyav ntawm qhov teeb meem kom tsis txhob tsuas yog hais txog cov tsos mob. Rau kev lag luam kilns, qhov ruaj khov ntawm refractories castables ncaj qha cuam tshuam rau lub qhov cub ua haujlwm kev nyab xeeb thiab kev pabcuam lub neej. Kev zam lub efflorescence ntxiab yog qhov tseem ceeb heev kom txo tau cov nqi tu thiab ua kom lub qhov cub ua haujlwm ntev.
