Feem ntau siv ntau yam ntawm cov khoom siv refractory

Ntawm cov khoom siv zoo tib yam thiab tshwj xeeb refractory, cov khoom siv feem ntau muaj xws li cov hauv qab no:
1. acidic
Silica cib thiab av nplaum cib yog siv ntau dua. Silica cib yog cov khoom siv silicon uas muaj ntau dua 93 feem pua ​​​​SiO2, thiab cov khoom siv raw siv yog silica, khib nyiab silica cib, thiab lwm yam. Silica bricks muaj zog tiv taus acidic slag yaig, tab sis muaj kev cuam tshuam rau alkaline slag yaig. Nws load softening kub yog siab heev, uas yog ze rau nws refractoriness. Tom qab rov calcination, lub ntim tsis ntsws, los yog txawm me ntsis expands, tab sis nws thermal shock kuj tsis zoo. Silica cib feem ntau yog siv rau hauv cov khoom siv thermal xws li coke ncu, iav melting furnaces, thiab acid steelmaking furnaces. Av nplaum cib muaj 30 feem pua ​​​​rau 46 feem pua ​​alumina. Nws siv cov av nplaum refractory ua cov khoom siv tseem ceeb. Nws muaj refractoriness ntawm 1580 txog 1770 degree thiab zoo thermal shock kuj. Nws yog cov khoom siv tsis muaj zog acidic refractory thiab muaj corrosion kuj rau acidic slag. Nws yog ib hom khoom siv refractory nrog cov khoom ntim ntau tshaj plaws.
2. Neutral
Lub ntsiab siv lead ua theem nyob rau hauv high-alumina cov khoom yog mullite thiab corundum. Cov ntsiab lus ntawm corundum nce nrog nce ntawm alumina cov ntsiab lus. Corundum cov khoom uas muaj ntau dua 95 feem pua ​​​​alumina yog cov khoom siv hluav taws xob zoo nrog kev siv dav. Chrome bricks feem ntau yog ua los ntawm chrome ore, thiab lub ntsiab siv lead ua theem yog chromite. Nws muaj qhov zoo corrosion kuj rau steel slag, tab sis tsis zoo thermal poob siab kuj thiab tsis tshua muaj deformation kub nyob rau hauv high kub load. Chrome-magnesia bricks ua los ntawm chrome ore thiab magnesia nyob rau hauv sib txawv proportions muaj zoo thermal poob siab kuj thiab yog tsuas yog siv raws li yooj yim qhib hearth rauv ru tsev cib.
Cov khoom siv carbonaceous yog lwm yam khoom siv nruab nrab refractory. Raws li cov khoom muaj pes tsawg leeg ntawm cov khoom siv raw thiab cov ntxhia hauv cov khoom, lawv tau muab faib ua peb pawg: carbon bricks, graphite khoom thiab cov khoom siv silicon carbide. Cov pa roj carbon cib yog ua los ntawm qib siab roj av coke, tar thiab pitch yog ntxiv raws li cov ntaub ntawv, thiab raug rho tawm haujlwm ntawm 1300 degree yam tsis muaj cua. Graphite khoom (tshwj tsis yog ntuj graphite) yog ua los ntawm cov ntaub ntawv carbonaceous los ntawm kev kho graphitization ntawm 2500-2800 degree hauv lub cub hluav taws xob. Cov khoom siv silicon carbide yog ua los ntawm silicon carbide thiab raug rho tawm haujlwm ntawm 1350-1400 degree nrog binders xws li av nplaum thiab silicon oxide. Silicon carbide ntxiv rau silicon hmoov kuj tuaj yeem ua rau cov khoom siv silicon nitride-silicon carbide nyob rau hauv cov cua nitrogen hauv lub cub hluav taws xob. Carbonaceous khoom muaj tsawg coefficient ntawm thermal expansion, siab thermal conductivity, zoo thermal poob siab kuj thiab siab zog ntawm kub. Nws tsis soften txawm tias tom qab siv mus sij hawm ntev ntawm qhov kub thiab txias, tsis corroded los ntawm tej acid thiab alkali, muaj ntsev zoo, thiab tsis wetted los ntawm hlau thiab slag. Nws yog lub teeb hauv qhov hnyav thiab yog cov khoom siv high-temperature resistant. Qhov tsis zoo yog tias nws yooj yim rau oxidize ntawm qhov kub thiab txias thiab yuav tsum tsis txhob siv rau hauv qhov chaw oxidizing. Carbonaceous khoom yog dav siv nyob rau hauv ob sab phlu ntawm high-temperature furnaces (kub hauv qab, hearth, qis ib feem ntawm lub cub tawg lub cev, thiab lwm yam), thiab hauv ob sab phlu ntawm non-ferrous hlau melting furnaces. Cov khoom siv graphite tuaj yeem siv los ua cov ntaub qhwv rau cov tshuaj tiv thaiv tank thiab petrochemical autoclaves. Silicon carbide thiab graphite cov khoom kuj tseem tuaj yeem ua rau hauv cov khoom siv rau melting tooj liab, kub thiab lub teeb alloys.
3. Alkaline
Sawv cev los ntawm cov khoom siv magnesium. Nws muaj ntau tshaj 80 feem pua ​​​​rau 85 feem pua ​​​​ntawm magnesium oxide, nrog periclase ua lub ntsiab siv lead ua theem. Cov ntaub ntawv tseem ceeb rau kev tsim cov pob zeb magnesia yog magnesite, seawater magnesia (uas tau los ntawm calcination ntawm magnesium hydroxide muab rho tawm los ntawm dej hiav txwv) thiab lwm yam. Zoo tiv thaiv alkaline slag thiab hlau slag. Lub melting point ntawm ntshiab magnesia yog siab li 2800 degree, yog li lub refractoriness ntawm magnesia cib yog siab tshaj cov av nplaum cib thiab silica cib. Txij li thaum nruab nrab -1950s, vim yog kev txais yuav cov pa oxygen-blowing converter steelmaking thiab siv cov txheej txheem qhib hearth rauv lub ru tsev, kev tsim cov khoom siv refractory tau maj mam nce ntxiv, thaum tsim cov av nplaum cib thiab silica cib muaj. txo. Basic refractories yog siv nyob rau hauv qhib hearth furnaces, oxygen-blown converters, hluav taws xob furnaces, non-ferrous hlau smelting thiab ib co high-temperature thermal khoom.