Mitundu yanji ya njerwa zapamwamba za alumina amagwiritsidwa ntchito kwambiri m’mafakitale?

Njerwa yapamwamba ya aluminiyamu imatanthawuza chinthu chopangidwa ndi sintered chomwe chili ndi zoposa 348% Al2O aluminosilicate kapena alumina wangwiro. Nthawi zambiri, njerwa zapamwamba za alumina zimakhala ndi zosakwana 80% Al2O3, ndipo zomwe zili ndi zoposa 80% Al2O3 zimatchedwa njerwa za corundum. Poyerekeza ndi njerwa zadongo, njerwa zapamwamba za aluminiyamu zili ndi maubwino apamwamba a refractoriness komanso kutentha kwakukulu kofewa pansi pa katundu. Pogwiritsa ntchito ng’anjo za mafakitale, njerwa zodziwika bwino za alumina zimagwera m’magulu asanu otsatirawa.

(1) Njerwa za aluminiyamu wamba

Mchere waukulu wa njerwa ndi mullite, corundum ndi galasi gawo. Monga zomwe zili mu Al2O3 muzinthu zowonjezera, mullite ndi corundum zimawonjezeka, gawo la galasi lidzachepa moyenerera, ndipo kukana komanso kutentha kwakukulu kwa mankhwalawa kudzawonjezeka moyenerera. Njerwa zodziwika bwino za aluminiyamu zimakhala ndi zinthu zambiri zotsutsana ndi moto kuposa zinthu zadongo, ndipo ndizinthu zomwe zimakhala ndi zotsatira zabwino zogwiritsira ntchito komanso ntchito zambiri. Amagwiritsidwa ntchito kwambiri m’mawotchi osiyanasiyana otentha. Poyerekeza ndi zinthu zadongo, moyo wautumiki wa ng’anjo ukhoza kuwongolera.

(2) Njerwa yofewa kwambiri ya aluminiyamu

Poyerekeza ndi njerwa wamba mkulu aluminiyamu, mkulu-katundu zofewa mkulu-alumina njerwa ndi osiyana mu gawo masanjidwewo ndi binder gawo: gawo la matrix limawonjezedwa ndi kuyika kwa miyala itatu, ndipo kapangidwe kake pambuyo kuwombera kuli pafupi ndi kapangidwe kawongopeka. mullite, yomwe imayambitsidwa momveka Gwiritsani ntchito zipangizo za aluminiyamu, monga ufa wa corundum, ufa wapamwamba wa aluminium corundum, etc.; sankhani dongo lapamwamba kwambiri ngati cholumikizira, ndipo gwiritsani ntchito zinthu zosiyanasiyana zadongo zomangirira kapena mullite zomangira zopangira kutengera mitundu. Kupyolera mu njira yomwe ili pamwambayi, kutentha kofewetsa katundu wa njerwa zapamwamba za aluminiyamu kumatha kuonjezedwa pafupifupi 50 mpaka 70°C.

(3) Njerwa yotsika kwambiri ya aluminiyamu

Limbikitsani kukana kwa njerwa zapamwamba za alumina potengera zomwe zimatchedwa kusalinganika. Ndiko kuti, molingana ndi kutentha kwa ng’anjo yogwiritsira ntchito, onjezerani miyala itatu yamchere, aluminiyamu, ndi zina zotero ku masanjidwewo kuti apange masanjidwewo pafupi kapena mullite kwathunthu, chifukwa kuchulukitsa kwa matrix kudzawonjezera mullite. zomwe zili muzinthuzo , Chepetsani gawo la galasi, ndipo mawonekedwe abwino kwambiri amakina ndi matenthedwe a mullite amathandizira kupititsa patsogolo kutentha kwakukulu kwa zinthuzo. Pofuna kupanga matrix kukhala mullite, kuwongolera Al2O3 / SiO2 ndiye chinsinsi. Njerwa zotsika kwambiri za aluminiyamu zimagwiritsidwa ntchito kwambiri m’ng’anjo zoyaka moto, ng’anjo zophulika ndi ng’anjo zina zotentha.

(4) Phosphate yomanga njerwa zazitali za alumina

Njerwa za aluminiyamu zomangika ndi phosphate zimapangidwa ndi aluminiyamu wapamwamba kwambiri kapena kalasi yoyamba yapamwamba kwambiri ya alumina bauxite clinker monga zopangira zazikulu, yankho la phosphate kapena aluminium phosphate solution monga chomangira, pambuyo poumba atolankhani owuma, kutentha kutentha pa 400 ~ 600 ℃ Zopangidwa ndi mankhwala opangidwa ndi mankhwala ophatikizika. Ndi njerwa yosawotchedwa. Pofuna kupewa kuchepa kwakukulu kwa mankhwalawa pakagwiritsidwa ntchito, nthawi zambiri ndikofunikira kuyambitsa zopangira zowonjezera kutentha, monga kyanite, silika, ndi zina zotere. Poyerekeza ndi njerwa za ceramic zomangika ndi aluminiyamu zazitali, magwiridwe ake odana ndi kuvula ndi abwinoko, koma kutentha kwake kofewetsa ndikotsika, ndipo kukana kwake kwa dzimbiri ndikocheperako. Choncho, kagawo kakang’ono ka corundum, mullite, ndi zina zotero, ziyenera kuwonjezeredwa kuti kulimbikitsa matrix. Njerwa za phosphate zomangika kwambiri za aluminiyamu zimagwiritsidwa ntchito kwambiri mu uvuni wa simenti, padenga lang’anjo yamagetsi ndi mbali zina zamoto.

(5) Njerwa zazing’ono zowonjezera aluminiyamu

Njerwayi imapangidwa makamaka ndi aluminiyamu yapamwamba kwambiri monga zopangira zazikulu, zowonjezeredwa ndi miyala itatu yokhazikika, ndipo imapangidwa molingana ndi njira yopangira njerwa zapamwamba za alumina. Pofuna kukulitsa bwino njerwa zapamwamba za alumina panthawi yogwiritsira ntchito, chinsinsi ndikusankha kuyika kwa miyala itatu ndi kukula kwake, ndikuwongolera kutentha kwamoto, kotero kuti gawo la miyala yosankhidwa ya miyala itatu ndi mullite ndi zina mwa zitatuzo. – miyala yamchere imakhalabe. Miyala yotsala ya miyala itatu imapangidwanso mulliteized (yoyambirira kapena yachiwiri mulliteized) pakagwiritsidwa ntchito, limodzi ndi kukulitsa kwa voliyumu. Miyala yamiyala itatu yosankhidwa makamaka ndi zinthu zophatikizika. Chifukwa kutentha kwapang’onopang’ono kwa miyala itatu yamwala ndi yosiyana, kufalikira komwe kumachitika chifukwa cha mullite petrochemical kumakhalanso kosiyana. Pogwiritsa ntchito izi, njerwa zapamwamba za aluminiyamu zimakhala ndi kukula kofananira chifukwa cha kutentha kosiyanasiyana. Kufinya kwa njerwa kumapangitsa kuti thupi likhale lolimba kwambiri, potero kumathandizira kukana kwa njerwa kuti zilowerere.