Uhlobo lwe-chromium
I-Chromium, uphawu lwe-element Cr, inombolo ye-athomu engu-24, isisindo se-athomu esingu-51.996, singese-transition metal element yeqembu le-VIB lethebula le-periodic lezinto zamakhemikhali. I-Chromium metal iyi-cubic crystal egxile emzimbeni, emhlophe njengesiliva, i-density engu-7.1g/cm³, iphuzu lokuncibilika lingu-1860℃, iphuzu lokubila lingu-2680℃, umthamo wokushisa othize ku-25℃ 23.35J/(mol·K), ukushisa komoya okungu-342.1kJ/mol, ukuqhuba ukushisa okungu-91.3 W/(m·K) (0-100°C), ukumelana (20°C) 13.2uΩ·cm, enezakhiwo ezinhle zemishini.
Kunezinhlobo ezinhlanu zama-valence e-chromium: +2, +3, +4, +5 kanye no-+6. Ngaphansi kwezimo zesenzo se-endogenous, i-chromium ngokuvamile iyi-+3 valence. Ama-compound ane-+trivalent chromium yiwona azinzile kakhulu. Ama-compound e-chromium +sixvalent, kufaka phakathi usawoti we-chromium, anezakhiwo eziqinile ze-oxidizing. I-ionic radii ye-Cr3+, AI3+ kanye ne-Fe3+ iyafana, ngakho-ke ingaba nokufana okubanzi. Ngaphezu kwalokho, izakhi ezingashintshwa nge-chromium yi-manganese, i-magnesium, i-nickel, i-cobalt, i-zinc, njll., ngakho-ke i-chromium isatshalaliswa kabanzi kumaminerali e-magnesium iron silicate kanye namaminerali angeziwe.
Isicelo
I-Chromium ingenye yezinsimbi ezisetshenziswa kakhulu embonini yanamuhla. Isetshenziswa kakhulu ekukhiqizweni kwensimbi engagqwali kanye nezinsimbi ezahlukahlukene ze-alloy ngesimo se-ferroalloys (njenge-ferrochrome). I-Chromium inezici zokuqina, ukumelana nokuguguleka, ukumelana nokushisa kanye nokugqwala. I-Chrome ore isetshenziswa kabanzi ezimbonini zensimbi, izinto eziphikisayo, imboni yamakhemikhali kanye nezimboni ze-foundry.
Embonini yezinsimbi, i-chromium ore isetshenziswa kakhulu ukuncibilikisa i-ferrochrome kanye ne-chromium yensimbi. I-Chromium isetshenziswa njengesithasiselo sensimbi ukukhiqiza izinhlobo ezahlukene zezinsimbi ezikhethekile eziqinile, ezingagqwali, ezingagugi, ezishisa kakhulu, nezimelana ne-oxidation, njengensimbi engagqwali, insimbi engagqwali, insimbi engagqwali, insimbi engagqwali, insimbi engagqwali, insimbi ethwala ibhola, insimbi yasentwasahlobo, insimbi yamathuluzi, njll. I-Chromium ingathuthukisa izakhiwo zemishini kanye nokumelana nokugugika kwensimbi. I-chromium yensimbi isetshenziswa kakhulu ukuncibilikisa ama-alloy akhethekile ane-cobalt, nickel, tungsten nezinye izinto. Ukufakwa kwe-chrome kanye ne-chromizing kungenza insimbi, ithusi, i-aluminium kanye nezinye izinsimbi zakhe indawo engagqwali, ekhanya futhi enhle.
Embonini yokungaguquguquki, i-chromium ore iyinto ebalulekile yokungaguquki esetshenziselwa ukwenza izitini ze-chrome, izitini ze-chrome magnesia, izinto zokungaguquki ezithuthukisiwe kanye nezinye izinto ezikhethekile zokungaguquki (ukhonkolo we-chrome). Izinto zokungaguquki ezisekelwe ku-chromium zifaka kakhulu izitini ezine-chrome ore kanye ne-magnesia, i-sintered magnesia-chrome clinker, izitini ze-magnesia-chrome ezincibilikisiwe, ezincibilikisiwe, ezigayiwe kahle bese zihlanganiswa. Zisetshenziswa kabanzi ezitsheni ezivulekile, ezitsheni zokungenisa, njll. I-Metallurgical converter kanye ne-rotary furnace lining yemboni yesamente, njll.
Embonini ye-foundry, i-chromium ore ngeke ihlangane nezinye izakhi zensimbi encibilikisiwe ngesikhathi senqubo yokuthulula, ine-coefficient yokukhulisa ukushisa ephansi, imelana nokungena kwensimbi, futhi isebenza kangcono ekupholiseni kune-zircon. I-Chrome ore ye-foundry inezidingo eziqinile zokwakheka kwamakhemikhali kanye nokusatshalaliswa kosayizi wezinhlayiya.
Embonini yamakhemikhali, ukusetshenziswa okuqondile kakhulu kwe-chromium ukukhiqiza isixazululo se-sodium dichromate (Na2Cr2O7·H2O), bese kulungiswa amanye ama-compound e-chromium ukuze asetshenziswe ezimbonini ezifana nama-pigment, izindwangu, i-electroplating, kanye nokwenza isikhumba, kanye nama-catalysts.
Impuphu ye-chromium ore egayiwe kahle iyisithako semvelo sokufaka umbala ekukhiqizweni kwengilazi, izinto zobumba kanye namathayili acwebezelayo. Lapho i-sodium dichromate isetshenziswa ukubhubhisa isikhumba, iphrotheni (i-collagen) kanye nama-carbohydrate esikhumbeni sokuqala asabela nezinto zamakhemikhali ukuze akhe inhlanganisela ezinzile, eba yisisekelo semikhiqizo yesikhumba. Embonini yezindwangu, i-sodium dichromate isetshenziswa njengesithako ekudayini indwangu, esinganamathisela ngempumelelo ama-molecule edayi kumakhemikhali e-organic; ingasetshenziswa futhi njenge-oxidant ekwenziweni kwamadayi kanye nezinto ezisetshenziswayo.
Amaminerali e-Chromium
Kunezinhlobo ezingaphezu kuka-50 zamaminerali aqukethe i-chromium atholakale emvelweni, kodwa iningi lawo linokuqukethwe okuphansi kwe-chromium kanye nokusatshalaliswa okusakazekile, okusetshenziswa kakhulu ezimbonini. Lawa maminerali aqukethe i-chromium angokwama-oxide, ama-chromate nama-silicates, ngaphezu kwama-hydroxide ambalwa, ama-iodate, ama-nitride nama-sulfide. Phakathi kwawo, amaminerali e-chromium nitride kanye ne-chromium sulfide atholakala kuphela kuma-meteorites.
Njengohlobo lwamaminerali emndenini we-chromium ore, i-chromite iyona kuphela iminerali ebalulekile yezimboni ye-chromium. Ifomula yamakhemikhali yethiyori yi-(MgFe)Cr2O4, lapho okuqukethwe yi-Cr2O3 kubala u-68%, kanti i-FeO ibala u-32%. Ekwakhekeni kwayo kwamakhemikhali, i-cation ye-trivalent ikakhulukazi yi-Cr3+, futhi kuvame ukuba ne-Al3+, Fe3+ kanye ne-Mg2+, Fe2+ isomorphic substitutions. Ku-chromite ekhiqizwayo yangempela, ingxenye ye-Fe2+ ivame ukushintshwa yi-Mg2+, kanti i-Cr3+ ishintshwa yi-Al3+ kanye ne-Fe3+ ngamazinga ahlukahlukene. Izinga eliphelele lokushintshaniswa kwe-isomorphic phakathi kwezingxenye ezahlukene ze-chromite alihambisani. Ama-cation okuxhumanisa ama-oda amane ikakhulukazi yi-magnesium kanye ne-iron, kanye nokushintshaniswa okuphelele kwe-isomorphic phakathi kwe-magnesium-iron. Ngokwendlela yokuhlukanisa okune, i-chromite ingahlukaniswa ngamaqembu amancane amane: i-magnesium chromite, i-iron-magnesium chromite, i-mafic-iron chromite kanye ne-iron-chromite. Ngaphezu kwalokho, i-chromite ivame ukuqukethe inani elincane le-manganese, ingxube efanayo ye-titanium, i-vanadium ne-zinc. Isakhiwo se-chromite singohlobo olujwayelekile lwe-spinel.
4. Izinga elijwayelekile le-chromium concentrate
Ngokwezindlela ezahlukene zokucubungula (ukumbiwa phansi kanye ne-ore yemvelo), i-chromium ore ye-metallurgy ihlukaniswe izinhlobo ezimbili: i-concentrate (G) kanye ne-lump ore (K). Bheka ithebula elingezansi.
Izidingo zekhwalithi ze-chromite ore ye-metallurgy
Ubuchwepheshe bokuhlomula nge-ore ye-Chrome
1) Ukukhethwa kabusha
Njengamanje, ukuhlukaniswa kwamandla adonsela phansi kunesikhundla esibalulekile ekuzuzeni i-chromium ore. Indlela yokuhlukaniswa kwamandla adonsela phansi, esebenzisa ukwakheka okuxekethile endaweni enamanzi njengendlela eyisisekelo yokuziphatha, iseyindlela eyinhloko yokucebisa i-chromium ore emhlabeni wonke. Imishini yokuhlukaniswa kwamandla adonsela phansi iyi-spiral chute kanye ne-centrifugal concentrator, futhi ububanzi bosayizi wezinhlayiya zokucubungula bubanzi kakhulu. Ngokuvamile, umehluko wobuningi phakathi kwamaminerali e-chromium kanye namaminerali e-gangue mkhulu kuno-0.8g/cm3, futhi ukuhlukaniswa kwamandla adonsela phansi kwanoma yiluphi usayizi wezinhlayiya olungaphezu kuka-100um kungaba okwanelisayo. Umphumela. Ama-coarse butter (100 ~ 0.5mm) ore ahlungwa noma akhethwe kusengaphambili ngokuhlomula okunamandla okuphakathi, okuyindlela yokonga kakhulu yokuhlomula.
2) Ukuhlukaniswa kwamagnetic
Ukuhlukaniswa kwamagnetic kuyindlela yokuzuza ehlukanisa amaminerali ensimini yamagnetic engalingani ngokusekelwe ekwehlukeni kwamagnetic kwamaminerali ku-ore. I-Chromite inezakhiwo zamagnetic ezibuthakathaka futhi ingahlukaniswa ngabahlukanisi bamagnetic abaphezulu be-gradient abama-vertical ring, abahlukanisi bamagnetic be-wet plate kanye neminye imishini. Ama-coefficients athile okuzwela amandla kagesi amaminerali e-chromium akhiqizwa ezindaweni ezahlukahlukene ezikhiqiza i-chromium ore emhlabeni awahlukile kakhulu, futhi afana nama-coefficients athile okuzwela amandla kagesi e-wolframite kanye ne-wolframite akhiqizwa ezindaweni ezahlukene.
Kunezimo ezimbili lapho kusetshenziswa ukuhlukaniswa kwamagnetic ukuthola i-chromium concentrate yezinga eliphezulu: esinye ukususa amaminerali anamandla amagnetic (ikakhulukazi i-magnetite) ku-ore ngaphansi kwensimu yamagnetic ebuthakathaka ukuze kwandiswe isilinganiso se-ferrochrome, kanti esinye ukusebenzisa insimu yamagnetic enamandla. Ukuhlukaniswa kwamaminerali e-gangue kanye nokubuyiselwa kwe-chromium ore (amaminerali anamandla amagnetic).
3) Ukukhetha kukagesi
Ukuhlukaniswa kukagesi kuyindlela yokuhlukanisa amaminerali e-chromium ore kanye ne-silicate gangue ngokusebenzisa izakhiwo zikagesi zamaminerali, njengomehluko ekuqhutshweni kwamandla kagesi kanye nokungaguquguquki kwe-dielectric.
4) Ukuntanta
Enkambisweni yokuhlukaniswa kwamandla adonsela phansi, i-chromite ore enezinhlayiya ezincane (-100um) ivame ukulahlwa njenge-tailings, kodwa i-chromite yalolu sayizi isenenani eliphezulu lokusetshenziswa, ngakho-ke indlela ye-flotation ingasetshenziswa ku-low-grade fine chromite ore Granular iyatholwa. Ukuntanta kwe-chromium ore enamaminerali angu-20% ~40% Cr2O3 kuma-tailings kanye namaminerali e-serpentine, olivine, rutile kanye ne-calcium magnesium carbonate njengamaminerali e-gangue. I-ore igaywa kahle ibe ngu-200μm, ingilazi yamanzi, i-phosphate, i-metaphosphate, i-fluorosilicate, njll. isetshenziselwa ukusabalalisa nokuvimbela i-sludge, kanti i-unsaturated fatty acid isetshenziswa njengeqoqo. Ukusabalala nokucindezela i-gangue sludge kubaluleke kakhulu enkambisweni ye-flotation. Ama-ion ensimbi njengensimbi kanye ne-lead angasebenza i-chromite. Uma inani le-pH le-slurry lingaphansi kuka-6, i-chromite ngeke intante. Ngamafuphi, ukusetshenziswa kwe-reagent ye-flotation kukhulu, izinga lokugxila alizinzile, futhi izinga lokululama liphansi. I-Ca2+ ne-Mg2+ ezincibilikisiwe kumaminerali e-gangue zinciphisa ukukhetha kwenqubo ye-flotation.
5) Ukuzuza ngamakhemikhali
Indlela yamakhemikhali iwukwelapha ngqo i-chromite ore ethile engenakuhlukaniswa ngendlela ebonakalayo noma izindleko zendlela ebonakalayo ziphakeme kakhulu. Isilinganiso se-Cr/Fe sokugxila okukhiqizwa ngendlela yamakhemikhali siphakeme kunesendlela evamile ebonakalayo. Izindlela zamakhemikhali zifaka: ukuhlanzwa okukhethiwe, ukunciphisa i-oxidation, ukuhlukaniswa kokuncibilika, ukuhlanzwa kwe-sulfuric acid kanye ne-chromic acid, ukunciphisa kanye nokuhlanzwa kwe-sulfuric acid, njll. Ukuhlanganiswa kwezindlela zamakhemikhali kanye nokwelashwa okuqondile kwe-chromium ore ngezindlela zamakhemikhali kungenye yezindlela eziyinhloko zokuzuza i-chromite namuhla. Izindlela zamakhemikhali zingakhipha i-chromium ngqo ku-ore futhi zikhiqize i-chromium carbide kanye ne-chromium oxide.
Isikhathi sokuthunyelwe: Ephreli-30-2021