Ndi mphamvu zapadera zakuthupi ndi zamakemikolo, kaolin ndi chuma chofunikira kwambiri cha mchere wosakhala wachitsulo mu zinthu zadothi, kupanga mapepala, rabala, mapulasitiki, zinthu zoyeretsera, kuyeretsa mafuta ndi madera ena aukadaulo wamakono wa mafakitale, ulimi ndi chitetezo cha dziko. Kuyera kwa kaolin ndi chizindikiro chofunikira cha kufunika kwake.
Zinthu zomwe zimakhudza kuyera kwa kaolin
Kaolin ndi mtundu wa dongo losalala kapena mwala wa dongo wopangidwa makamaka ndi mchere wa kaolinite. Fomula yake ya kristalo ndi 2SiO2 · Al2O3 · 2H2O. Michere yochepa yopanda dongo ndi quartz, feldspar, mchere wachitsulo, titaniyamu, aluminiyamu hydroxide ndi ma oxide, zinthu zachilengedwe, ndi zina zotero.
Kapangidwe ka kristalo ka kaolin
Malinga ndi momwe zinthu zilili komanso mtundu wa zinthu zosafunika mu kaolin, zinthu zosafunika zomwe zimayambitsa kuchepa kwa kuyera kwa kaolin zitha kugawidwa m'magulu atatu: organic carbon; Zinthu za pigment, monga Fe, Ti, V, Cr, Cu, Mn, ndi zina zotero; Michere yakuda, monga biotite, chlorite, ndi zina zotero. Kawirikawiri, kuchuluka kwa V, Cr, Cu, Mn ndi zinthu zina mu kaolin ndi kochepa, komwe sikukhudza kuyera kwenikweni. Kapangidwe ka mchere ndi kuchuluka kwa chitsulo ndi titaniyamu ndi zinthu zazikulu zomwe zimakhudza kuyera kwa kaolin. Kukhalapo kwawo sikungokhudza kuyera kwachilengedwe kwa kaolin, komanso kumakhudza kuyera kwake kokhala ndi calcium. Makamaka, kukhalapo kwa iron oxide kumakhudza mtundu wa dongo ndipo kumachepetsa kuwala kwake ndi kukana moto. Ndipo ngakhale kuchuluka kwa oxide, hydroxide ndi hydrated oxide ya iron oxide ndi 0.4%, ndikokwanira kupatsa dongo utoto wofiira kukhala wachikasu. Ma iron oxides ndi ma hydroxide awa akhoza kukhala hematite (wofiira), maghemite (wofiira-bulauni), goethite (wachikasu wofiirira), limonite (lalanje), hydrated iron oxide (wofiira wofiirira), ndi zina zotero. Tinganene kuti kuchotsa zinyalala zachitsulo mu kaolin kumachita gawo lofunika kwambiri pakugwiritsa ntchito bwino kaolin.
Mkhalidwe wa chinthu chachitsulo
Kupezeka kwa chitsulo mu kaolin ndiye chinthu chachikulu chomwe chimatsimikizira njira yochotsera chitsulo. Kafukufuku wambiri amakhulupirira kuti chitsulo chopangidwa ndi kristalo mu mawonekedwe a tinthu tating'onoting'ono timasakanikirana mu kaolin, pomwe chitsulo chopanda mawonekedwe chimakutidwa pamwamba pa tinthu tating'onoting'ono ta kaolin. Pakadali pano, kupezeka kwa chitsulo mu kaolin kumagawidwa m'mitundu iwiri kunyumba ndi kunja: imodzi ili mu kaolinite ndi mchere wowonjezera (monga mica, titanium dioxide ndi illite), yomwe imatchedwa structural iron; inayo ili mu mawonekedwe a mchere wodziyimira pawokha wachitsulo, wotchedwa free iron (kuphatikiza chitsulo chapamwamba, chitsulo chopangidwa ndi kristalo chopyapyala ndi chitsulo chopanda mawonekedwe).
Chitsulo chomwe chimachotsedwa pochotsa chitsulo ndi kuyeretsa kaolin ndi chitsulo chaulere, makamaka kuphatikiza magnetite, hematite, limonite, siderite, pyrite, ilmenite, jarosite ndi mchere wina; Chitsulo chambiri chilipo mu mawonekedwe a colloidal limonite yofalikira kwambiri, ndipo pang'ono mu mawonekedwe a goethite yozungulira, ya acicular komanso yosasinthasintha ndi hematite.
Njira yochotsera chitsulo ndi kuyeretsa kaolin
Kulekanitsa madzi
Njirayi imagwiritsidwa ntchito makamaka pochotsa mchere woipa monga quartz, feldspar ndi mica, ndi zinthu zonyansa monga miyala, komanso mchere wina wachitsulo ndi titaniyamu. Michere yoipa yokhala ndi kuchuluka kofanana ndi kaolin singachotsedwe, ndipo kuyera bwino sikuonekera bwino, komwe ndikoyenera kuyeretsa ndi kuyeretsa miyala ya kaolin yapamwamba kwambiri.
Kulekanitsa maginito
Zonyansa za mchere wachitsulo mu kaolin nthawi zambiri zimakhala zamaginito ofooka. Pakadali pano, njira yolekanitsira maginito amphamvu kwambiri imagwiritsidwa ntchito kwambiri, kapena mchere wofooka wa maginito umasinthidwa kukhala magnesium oxide wamphamvu wa maginito akamawotchedwa, kenako nkuchotsedwa ndi njira yachizolowezi yolekanitsira maginito.
Cholekanitsa maginito cha mphete yopingasa yokhala ndi maginito okwera kwambiri
Cholekanitsa maginito cha gradient cha slurry yamagetsi
Cholekanitsa maginito chotsika kutentha kwambiri
Njira yoyandama
Njira yodulira yagwiritsidwa ntchito pochiza kaolin kuchokera ku zinthu zoyambira ndi zachiwiri. Mu njira yodulira, tinthu ta kaolinite ndi mica timalekanitsidwa, ndipo zinthu zoyeretsedwazo zimakhala zinthu zingapo zoyenera zopangira mafakitale. Kulekanitsa kaolinite ndi feldspar mwa kusankha kudulira nthawi zambiri kumachitika mu slurry yokhala ndi pH yolamulidwa.
Njira yochepetsera
Njira yochepetsera ndikugwiritsa ntchito chochepetsera kuti muchepetse zinyalala zachitsulo (monga hematite ndi limonite) mu trivalent state ya kaolin kupita ku soluble bivalent iron iron ions, zomwe zimachotsedwa posefa ndi kutsuka. Kuchotsa zinyalala za Fe3+ kuchokera ku kaolin yamafakitale nthawi zambiri kumachitika pophatikiza ukadaulo wa physical (magnetic separation, selective flocculation) ndi mankhwala a mankhwala pansi pa acidity kapena reduction conditions.
Sodium hydrosulfite (Na2S2O4), yomwe imadziwikanso kuti sodium hydrosulfite, ndi yothandiza kuchepetsa ndi kutulutsa chitsulo kuchokera ku kaolin, ndipo pakadali pano imagwiritsidwa ntchito m'makampani a kaolin. Komabe, njira iyi iyenera kuchitika pansi pa acidity yamphamvu (pH<3), zomwe zimapangitsa kuti ndalama zogwirira ntchito zikhale zokwera komanso kuwononga chilengedwe. Kuphatikiza apo, mphamvu za mankhwala a sodium hydrosulfite sizokhazikika, zimafuna malo apadera komanso okwera mtengo osungira ndi mayendedwe.
Thiourea dioxide: (NH2) 2CSO2, TD) ndi mankhwala amphamvu ochepetsa mphamvu ya zinthu, omwe ali ndi ubwino wochepetsa mphamvu ya zinthu, kusamala chilengedwe, kuchepa kwa kuwonongeka kwa zinthu, chitetezo komanso mtengo wotsika wa kupanga zinthu. Fe3+ yosasungunuka mu kaolin imatha kuchepetsedwa kukhala Fe2+ kudzera mu TD yosungunuka.
Pambuyo pake, kuyera kwa kaolin kumatha kuwonjezeka pambuyo posefa ndi kutsuka. TD imakhala yokhazikika kwambiri kutentha kwa chipinda komanso m'malo osalowerera. Mphamvu yochepetsera ya TD imatha kupezeka pokhapokha ngati pali alkalinity yamphamvu (pH>10) kapena kutentha (T>70 ° C), zomwe zimapangitsa kuti ntchito ikhale yovuta komanso yokwera mtengo.
Njira yothira okosijeni
Chithandizo cha okosijeni chimaphatikizapo kugwiritsa ntchito ozone, hydrogen peroxide, potaziyamu permanganate ndi sodium hypochlorite kuti muchotse mpweya wothira kuti muyeretse bwino. Kaolin yomwe ili mkati mwa malo ozama pansi pa katundu wokhuthala ndi imvi, ndipo chitsulo chomwe chili mu kaolin chili mu mkhalidwe wochepetsera. Gwiritsani ntchito zinthu zolimbikitsa okosijeni monga ozone kapena sodium hypochlorite kuti muwonjeze FeS2 yosasungunuka mu pyrite kukhala Fe2+, kenako muzimutsuka kuti muchotse Fe2+ mu dongosolo.
Njira yochotsera asidi
Njira yochotsera asidi ndikusintha zinyalala zosasungunuka zachitsulo mu kaolin kukhala zinthu zosungunuka mu njira za acidic (hydrochloric acid, sulfuric acid, oxalic acid, ndi zina zotero), motero kuzindikira kulekana ndi kaolin. Poyerekeza ndi ma organic acid ena, oxalic acid imaonedwa kuti ndi yodalirika kwambiri chifukwa cha mphamvu yake ya asidi, mphamvu yabwino yolumikizirana komanso mphamvu yochepetsera kwambiri. Ndi oxalic acid, chitsulo chosungunuka chimatha kuchotsedwa mu njira yochotsera madzi mu mawonekedwe a ferrous oxalate, ndipo chikhoza kukonzedwanso kuti chipange hematite yoyera kudzera mu calcination. Oxalic acid ingapezeke motchipa kuchokera ku njira zina zamafakitale, ndipo panthawi yopanga ceramic, oxalate iliyonse yotsala muzinthu zomwe zakonzedwa idzasungunuka kukhala carbon dioxide. Ofufuza ambiri aphunzira zotsatira za kusungunuka kwa iron oxide ndi oxalic acid.
Njira yowerengera kutentha kwambiri
Kupaka calcination ndi njira yopangira zinthu zapadera za kaolin. Malinga ndi kutentha kwa mankhwala, mitundu iwiri yosiyanasiyana ya kaolin yokhala ndi calcium imapangidwa. Kupaka calcination pa kutentha kwa 650-700 ℃ kumachotsa gulu la hydroxyl, ndipo nthunzi yamadzi yomwe imatuluka imawonjezera kusinthasintha ndi kutseguka kwa kaolin, komwe ndi khalidwe labwino kwambiri la kugwiritsa ntchito pepala lopaka. Kuphatikiza apo, potenthetsa kaolin pa 1000-1050 ℃, sikuti kungowonjezera kusinthasintha, komanso kupeza kuyera kwa 92-95%.
Kuchuluka kwa chlorine
Chitsulo ndi titaniyamu zinachotsedwa mu mchere wa dongo, makamaka kaolin pogwiritsa ntchito chlorination, ndipo zotsatira zabwino zinapezeka. Pakutentha kwambiri (700 ℃ - 1000 ℃), kaolinite yasinthidwa kukhala dehydroxylation kuti ipange metakaolinite, ndipo pa kutentha kwakukulu, magawo a spinel ndi mullite amapangidwa. Kusintha kumeneku kumawonjezera hydrophobicity, kuuma ndi kukula kwa tinthu tating'onoting'ono kudzera mu sintering. Michere yomwe imakonzedwa motere ingagwiritsidwe ntchito m'mafakitale ambiri, monga mapepala, PVC, rabara, mapulasitiki, zomatira, kupukuta ndi mankhwala otsukira mano. Hydrophobicity yapamwamba imapangitsa mcherewu kukhala wogwirizana kwambiri ndi machitidwe achilengedwe.
Njira ya microbiological
Ukadaulo woyeretsa ma microbial wa mchere ndi nkhani yatsopano yokonza mchere, kuphatikizapo ukadaulo wochotsa ma microbial ndi ukadaulo wochotsa ma microbial. Ukadaulo wochotsa ma microbial wa mchere ndi ukadaulo wochotsa womwe umagwiritsa ntchito kuyanjana kwakukulu pakati pa tizilombo ndi mchere kuti uwononge kristalo lattice ya mchere ndikusungunula zinthu zothandiza. Oxidized pyrite ndi sulfide ores zina zomwe zili mu kaolin zimatha kuyeretsedwa ndi ukadaulo wochotsa ma microbial. Tizilombo toyambitsa matenda tomwe timagwiritsidwa ntchito kwambiri ndi Thiobacillus ferroxidans ndi mabakiteriya ochepetsa Fe. Njira ya microbiological ili ndi mtengo wotsika komanso kuipitsa chilengedwe kochepa, zomwe sizikhudza mawonekedwe ndi kapangidwe ka kaolin. Ndi njira yatsopano yoyeretsa ndi kuyeretsa yokhala ndi chiyembekezo chakukula kwa mchere wa kaolin.
Chidule
Kuchotsa chitsulo ndi kuyeretsa kaolin kuyenera kusankha njira yabwino kwambiri malinga ndi mitundu yosiyanasiyana ya zinthu komanso zolinga zosiyanasiyana zogwiritsira ntchito, kukonza magwiridwe antchito a mchere wa kaolin, ndikupangitsa kuti ikhale yogwiritsidwa ntchito bwino komanso yopindulitsa kwambiri. Chitukuko chamtsogolo chiyenera kukhala kuphatikiza makhalidwe a njira zamakemikolo, njira zakuthupi ndi njira zama microbiological mwachilengedwe, kuti apereke mawonekedwe athunthu ku zabwino zake ndikuletsa zoyipa ndi zofooka zake, kuti akwaniritse bwino kuyeretsa. Nthawi yomweyo, ndikofunikiranso kuphunzira njira yatsopano yochotsera zodetsa zosiyanasiyana ndikuwongolera njira yochotsera chitsulo ndi kuyeretsa kaolin kupita ku malo obiriwira, ogwira ntchito bwino komanso otsika mpweya.
Nthawi yotumizira: Mar-02-2023