Chikhalidwe cha chromium
Chromium, chizindikiro cha Cr, nambala ya atomiki 24, misa ya atomiki 51.996, ndi gawo la chitsulo chosinthira cha gulu VIB patebulo la periodic la zinthu zamankhwala.Chromium zitsulo ndi thupi likulu kiyubiki kristalo, siliva woyera, osalimba 7.1g/cm³, kusungunuka mfundo 1860 ℃, kuwira mfundo 2680 ℃, enieni kutentha mphamvu pa 25 ℃ 23.35J/(mol · K), kutentha kwa vaporization 342.1kJ J / 342.1kJ mol, matenthedwe matenthedwe 91.3 W/(m·K) (0-100°C), resistivity (20°C) 13.2uΩ·cm, okhala ndi makina abwino.
Pali ma valences asanu a chromium: +2, +3, +4, +5 ndi +6.Pansi pa zochitika zamkati, chromium nthawi zambiri imakhala +3 valence.Mankhwala okhala ndi + trivalent chromium ndiwokhazikika kwambiri.+ Mitundu isanu ndi umodzi ya chromium, kuphatikiza mchere wa chromium, imakhala ndi ma oxidizing amphamvu.Radiyo ya ionic ya Cr3 +, AI3 + ndi Fe3 + ndi yofanana, kotero iwo akhoza kukhala ndi zofanana zambiri.Kuphatikiza apo, zinthu zomwe zitha kusinthidwa ndi chromium ndi manganese, magnesium, nickel, cobalt, zinki, ndi zina zambiri, kotero chromium imagawidwa kwambiri mu mchere wa magnesium iron silicate ndi mchere wowonjezera.
Kugwiritsa ntchito
Chromium ndi imodzi mwazitsulo zomwe zimagwiritsidwa ntchito kwambiri m'makampani amakono.Amagwiritsidwa ntchito makamaka popanga zitsulo zosapanga dzimbiri ndi zitsulo zosiyanasiyana za alloy mu mawonekedwe a ferroalloys (monga ferrochrome).Chromium ili ndi mawonekedwe olimba, osavala, osatentha komanso osachita dzimbiri.Chrome ore imagwiritsidwa ntchito kwambiri muzitsulo, zida zokanira, mafakitale amafuta ndi mafakitale oyambira.
M'makampani opanga zitsulo, miyala ya chromium imagwiritsidwa ntchito makamaka kusungunula ferrochrome ndi zitsulo chromium.Chromium imagwiritsidwa ntchito ngati chowonjezera chachitsulo kuti ipange mitundu yambiri yamphamvu kwambiri, yosagwira dzimbiri, yosamva kuvala, kutentha kwambiri, komanso zitsulo zapadera zolimbana ndi okosijeni, monga chitsulo chosapanga dzimbiri, chitsulo chosapanga asidi, chitsulo chosagwira kutentha, mpira kubala zitsulo, masika zitsulo, chida zitsulo, etc. Chromium akhoza kumapangitsanso katundu makina ndi kuvala kukana zitsulo.Chromium yachitsulo imagwiritsidwa ntchito makamaka kusungunula ma aloyi apadera okhala ndi cobalt, faifi tambala, tungsten ndi zinthu zina.Chrome plating ndi chromizing zimatha kupanga chitsulo, mkuwa, aluminiyamu ndi zitsulo zina kupanga malo osagwirizana ndi dzimbiri, omwe ndi owala komanso okongola.
M'makampani opondereza, miyala ya chromium ndi chinthu chofunikira chokanira chomwe chimagwiritsidwa ntchito popanga njerwa za chrome, njerwa za chrome magnesia, zotsukira zapamwamba ndi zida zina zapadera zokanira (chrome konkriti).Zipangizo zopangira chromium zimaphatikizanso njerwa zokhala ndi chrome ore ndi magnesia, sintered magnesia-chrome clinker, njerwa zosungunuka za magnesia-chrome, chitsulo chosungunula, pansi bwino kenako ndi njerwa za magnesia-chrome.Amagwiritsidwa ntchito kwambiri m'ng'anjo zamoto zotseguka, ng'anjo zolowera, ndi zina zambiri.
M'makampani opangira zinthu, miyala ya chromium sichingagwirizane ndi zinthu zina muzitsulo zosungunuka panthawi yothira, imakhala ndi mphamvu yowonjezera yowonjezera kutentha, imagonjetsedwa ndi chitsulo, ndipo imakhala ndi ntchito yabwino yozizira kuposa zircon.Chrome ore for foundry imakhala ndi zofunikira pakupanga mankhwala komanso kugawa kwa tinthu.
M'makampani opanga mankhwala, kugwiritsa ntchito chromium mwachindunji ndi kupanga sodium dichromate (Na2Cr2O7·H2O) yankho, ndikukonzekera mankhwala ena a chromium kuti agwiritsidwe ntchito m'mafakitale monga inki, nsalu, electroplating, ndi kupanga zikopa, komanso zopangira zopangira. .
Ufa wa chromium ore wopangidwa bwino ndi wopangira utoto wachilengedwe popanga magalasi, zoumba ndi matailosi owala.Pamene sodium dichromate imagwiritsidwa ntchito kuwononga chikopa, mapuloteni (collagen) ndi chakudya cham'madzi mu chikopa choyambirira amachitira zinthu ndi mankhwala kuti apange cholimba chokhazikika, chomwe chimakhala maziko a zinthu zachikopa.M'makampani opanga nsalu, sodium dichromate imagwiritsidwa ntchito ngati mordant mu utoto wa nsalu, womwe umatha kumangirira mamolekyu a utoto kuzinthu zachilengedwe;itha kugwiritsidwanso ntchito ngati okosijeni popanga utoto ndi zapakati.
Chromium mchere
Pali mitundu yopitilira 50 ya mchere wokhala ndi chromium yomwe yapezedwa m'chilengedwe, koma ambiri amakhala ndi chromium yotsika komanso kugawa kwamwazi, komwe kumakhala ndi phindu lotsika pamafakitale.Michere iyi yokhala ndi chromium ndi ya oxides, chromates ndi silicates, kuphatikiza ma hydroxides ochepa, ma iodates, nitrides ndi sulfides.Pakati pawo, mchere wa chromium nitride ndi chromium sulfide amapezeka mu meteorites okha.
Monga mtundu wa mchere wamtundu wa chromium ore subfamily, chromite ndiye mchere wofunikira wamafakitale wa chromium.Theoretical Chemical formula ndi (MgFe)Cr2O4, momwe Cr2O3 imapanga 68%, ndipo FeO imawerengera 32%.M'mapangidwe ake a mankhwala, trivalent cation makamaka Cr3 +, ndipo nthawi zambiri pali Al3+, Fe3+ ndi Mg2+, Fe2+ isomorphic m'malo.Mu chromite yeniyeni yopangidwa, gawo la Fe2 + nthawi zambiri limasinthidwa ndi Mg2 +, ndipo Cr3 + imasinthidwa ndi Al3 + ndi Fe3 + ku madigiri osiyanasiyana.Mlingo wathunthu wa kusintha kwa isomorphic pakati pa zigawo zosiyanasiyana za chromite sizofanana.Ma cations owongolera anayi amakhala makamaka magnesiamu ndi chitsulo, komanso m'malo mwa isomorphic pakati pa magnesium-iron.Malinga ndi njira ya magawo anayi, chromite ikhoza kugawidwa m'magulu anayi: magnesium chromite, iron-magnesium chromite, mafic-iron chromite ndi iron-chromite.Kuphatikiza apo, chromite nthawi zambiri imakhala ndi manganese pang'ono, A homogeneous osakaniza a titaniyamu, vanadium ndi zinki.Mapangidwe a chromite ndi amtundu wa spinel wamba.
4. Muyezo wabwino wa chromium concentrate
Malinga ndi njira zosiyanasiyana zopangira (mineralization ndi ore zachilengedwe), miyala ya chromium ya zitsulo imagawidwa m'mitundu iwiri: concentrate (G) ndi phala ore (K).Onani tebulo ili m'munsimu.
Zofunikira zamtundu wa chromite ore pazitsulo
Tekinoloje ya Chrome ore Beneficiation
1) Kusankhidwanso
Pakadali pano, kulekanitsa mphamvu yokoka kuli ndi gawo lofunikira pakupindula kwa chromium ore.Njira yolekanitsa mphamvu yokoka, yomwe imagwiritsa ntchito kusanjika kotayirira m'malo amadzi monga momwe zimakhalira, ikadali njira yayikulu yolemeretsa miyala ya chromium padziko lonse lapansi.The mphamvu yokoka kulekana zida ndi chute ozungulira ndi concentrator centrifugal, ndi processing tinthu kukula osiyanasiyana ndi lonse.Kawirikawiri, kusiyana kwa kachulukidwe pakati pa mchere wa chromium ndi mchere wa gangue ndi waukulu kuposa 0.8g/cm3, ndipo kulekanitsa mphamvu yokoka ya kukula kwa tinthu kakang'ono kuposa 100um kungakhale kogwira mtima.zotsatira za.Mitsempha yolimba (100 ~ 0.5mm) ore imasanjidwa kapena kusankhidwatu ndi heavy-medium beneficiation, yomwe ndi njira yopezera ndalama zambiri.
2) Kupatukana kwa maginito
Kupatukana kwa maginito ndi njira yopindulitsa yomwe imazindikira kulekanitsa kwa mchere mu gawo la maginito lomwe silinafanane potengera kusiyana kwa maginito kwa mchere mu ore.Chromite ali ndi mphamvu maginito ofooka ndipo akhoza kulekanitsidwa ndi ofukula mphete mkulu gradient maginito olekanitsa, chonyowa mbale maginito olekanitsa ndi zipangizo zina.Ma coefficients enieni a maginito a mchere wa chromium omwe amapangidwa m'malo osiyanasiyana opangira chromium ore padziko lapansi siwosiyana kwambiri, ndipo ndi ofanana ndi maginito amphamvu a wolframite ndi wolframite opangidwa m'madera osiyanasiyana.
Pali zinthu ziwiri pakugwiritsa ntchito kupatukana kwa maginito kuti mupeze chromium yapamwamba kwambiri: imodzi ndiyo kuchotsa mchere wamphamvu wa maginito (makamaka magnetite) mu ore pansi pa mphamvu ya maginito yofooka kuti muwonjezere chiŵerengero cha ferrochrome, ndipo ina ndiyo kugwiritsa ntchito mphamvu maginito.Kupatukana kwa mchere wa gangue ndikubwezeretsanso kwa chromium ore (yofooka maginito mchere).
3) Kusankhidwa kwa magetsi
Kulekanitsa magetsi ndi njira yolekanitsira chromium ore ndi silicate gangue minerals pogwiritsa ntchito mphamvu zamagetsi za mchere, monga kusiyana kwa conductivity ndi dielectric constant.
4) Kuyandama
M'kati mwa kulekanitsa mphamvu yokoka, miyala yamtengo wapatali (-100um) ya chromite nthawi zambiri imatayidwa ngati michira, koma chromite ya kukula uku imakhalabe ndi mtengo wapamwamba wogwiritsira ntchito, kotero njira yoyandama ingagwiritsidwe ntchito pamtengo wotsika wa Granular chromite ore. wachira.Kuyandama kwa chromium ore ndi 20% ~ 40% Cr2O3 mu michira ndi serpentine, olivine, rutile ndi calcium magnesium carbonate mchere ngati mchere wa gangue.Miyalayo imadulidwa bwino mpaka 200μm, galasi lamadzi, phosphate, metaphosphate, fluorosilicate, ndi zina zotero zimagwiritsidwa ntchito kufalitsa ndi kuletsa matope, ndipo unsaturated mafuta acid amagwiritsidwa ntchito ngati osonkhanitsa.Kubalalitsidwa ndi kuponderezedwa kwa gangue sludge ndikofunikira kwambiri pakuyandama.Maioni achitsulo monga chitsulo ndi lead amatha kuyambitsa chromite.Pamene pH mtengo wa slurry uli pansi pa 6, chromite sichidzayandama.Mwachidule, kumwa kwa reagent flotation ndi kwakukulu, kalasi yowonongeka ndi yosakhazikika, ndipo kuchira kumakhala kochepa.Ca2+ ndi Mg2+ osungunuka kuchokera ku mchere wa gangue amachepetsa kusankha kwa njira yoyandama.
5) Chemical Beneficiation
Njira yama Chemical ndikuchiza mwachindunji miyala ina ya chromite yomwe singasiyanitsidwe ndi njira yakuthupi kapena mtengo wanjira yakuthupi ndiwokwera kwambiri.Chiyerekezo cha Cr/Fe cha concentrate chopangidwa ndi njira yamankhwala ndichokwera kuposa cha njira wamba.Njira zama mankhwala ndi monga: kusankha leaching, kuchepetsa makutidwe ndi okosijeni, kusungunuka kulekanitsa, sulfuric acid ndi chromic acid leaching, kuchepetsa ndi sulfuric acid leaching, etc. mayendedwe pakupindula kwa chromite masiku ano.Njira zama mankhwala zimatha kutulutsa chromium mwachindunji mu ore ndikupanga chromium carbide ndi chromium oxide.
Nthawi yotumiza: Apr-30-2021