Uhlobo lwe-chromium
I-Chromium, uphawu lwe-element Cr, inombolo ye-athomu 24, ubunzima be-athomu obuhambelanayo 51.996, buyinxalenye ye-transition metal element yeqela le-VIB le-periodic table yezinto zeekhemikhali. I-Chromium metal yi-body-centered cubic crystal, isilivere-mhlophe, i-density 7.1g/cm³, i-melting point 1860℃, i-billing point 2680℃, i-specific heat capacity kwi-25℃ 23.35J/(mol·K), i-vaporization heat 342.1kJ/mol, i-thermal conductivity 91.3 W/(m·K) (0-100°C), i-resistivity (20°C) 13.2uΩ·cm, eneempawu ezilungileyo ze-mechanical.
Kukho ii-valences ezintlanu ze-chromium: +2, +3, +4, +5 kunye ne-+6. Phantsi kweemeko zesenzo se-endogenous, i-chromium ngokubanzi yi-+3 valence. Ii-compounds ezine-+trivalent chromium zezona zizinzileyo. Ii-compounds ze-+sixvalent chromium, kuquka neetyuwa ze-chromium, zineempawu ezinamandla ze-oxidizing. I-ionic radii ye-Cr3+, AI3+ kunye ne-Fe3+ ziyafana, ngoko ke zinokuba noluhlu olubanzi lokufana. Ukongeza, izinto ezinokutshintshwa nge-chromium yi-manganese, i-magnesium, i-nickel, i-cobalt, i-zinc, njl.njl., ngoko ke i-chromium isasazwa kakhulu kwi-magnesium iron silicate minerals kunye nee-accessory minerals.
Isicelo
I-Chromium yenye yezona zinyithi zisetyenziswa kakhulu kushishino lwanamhlanje. Isetyenziswa kakhulu ekuveliseni intsimbi engagqwaliyo kunye neentsimbi ezahlukeneyo ze-alloy ngohlobo lwee-ferroalloys (ezifana ne-ferrochrome). I-Chromium ineempawu zokuba lukhuni, alugugi, alutshisi kwaye alunamhlwa. I-Chrome ore isetyenziswa kakhulu kwi-metallurgy, kwizixhobo ezichasayo, kushishino lweekhemikhali nakwimizi-mveliso ye-foundry.
Kwishishini lesinyithi, i-chromium ore isetyenziswa kakhulu ukunyibilikisa i-ferrochrome kunye ne-chromium yesinyithi. I-Chromium isetyenziswa njengesongezelelo sesinyithi ukuvelisa iintlobo ngeentlobo zeentsimbi ezikhethekileyo eziqinileyo, ezingagqwaliyo, ezingagugiyo, ezishushu kakhulu, nezimelana ne-oxidation, ezifana nentsimbi engagqwaliyo, intsimbi engagqwaliyo, intsimbi engagqwaliyo, intsimbi engagqwaliyo, intsimbi ethwala ibhola, intsimbi yentwasahlobo, intsimbi yesixhobo, njl. I-Chromium inokuphucula iipropati zoomatshini kunye nokumelana nokugqwala kwentsimbi. I-chromium yesinyithi isetyenziswa kakhulu ukunyibilikisa ii-alloys ezikhethekileyo ezine-cobalt, nickel, tungsten kunye nezinye izinto. I-Chrome plating kunye ne-chromizing zinokwenza intsimbi, ubhedu, i-aluminium kunye nezinye iintsimbi zenze umphezulu ongagqwaliyo, okhanyayo kwaye umhle.
Kwishishini lokuchasa, i-chromium ore sisixhobo esibalulekileyo sokuchasa esisetyenziselwa ukwenza izitena ze-chrome, izitena ze-chrome magnesia, ii-refractories eziphambili kunye nezinye izinto ezikhethekileyo zokuchasa (ikhonkrithi ye-chrome). Ii-refractories ezisekelwe kwi-chromium ziquka ikakhulu izitena ezine-chrome ore kunye ne-magnesia, i-sintered magnesia-chrome clinker, izitena ze-magnesia-chrome ezinyibilikisiweyo, ezinyibilikisiweyo, ezicoliweyo kakuhle kwaye ezibotshelelweyo ze-magnesia-chrome. Zisetyenziswa kakhulu kwii-oven oven, kwii-induction oven, njl. I-Metallurgical converter kunye ne-rotary furnace lining yeshishini lesamente, njl.
Kwishishini lezinto eziqanjwe ngomatshini, i-chromium ore ayizukusebenzisana nezinye izinto kwintsimbi enyibilikisiweyo ngexesha lenkqubo yokugalela, inomlinganiselo ophantsi wokwandisa ubushushu, ayingeni kwisinyithi, kwaye isebenza ngcono ekupholiseni kune-zircon. I-Chrome ore yezinto eziqanjwe ngomatshini ineemfuno ezingqongqo malunga nokwakheka kweekhemikhali kunye nokusasazwa kobukhulu beentwana.
Kwishishini leekhemikhali, ukusetyenziswa ngokuthe ngqo kwe-chromium kukuvelisa isisombululo se-sodium dichromate (Na2Cr2O7·H2O), uze emva koko ulungiselele ezinye iikhompawundi ze-chromium eziza kusetyenziswa kumashishini afana nee-pigments, amalaphu, i-electroplating, kunye nokwenza ulusu, kunye nee-catalysts.
Umgubo we-chromium ore ocoliweyo kakuhle yiarhente yendalo yokufaka imibala kwimveliso yeglasi, i-ceramics kunye neethayile ezicwebezelayo. Xa i-sodium dichromate isetyenziselwa ukutshabalalisa ulusu, iproteni (i-collagen) kunye nee-carbohydrates kwisikhumba sokuqala zidibana nezinto zeekhemikhali ukuze zenze i-complex ezinzileyo, eba sisiseko seemveliso zesikhumba. Kwishishini lempahla, i-sodium dichromate isetyenziswa njenge-mordant kwidayi yelaphu, enokuncamathisela ngempumelelo iimolekyuli zedayi kwiikhompawundi ze-organic; ingasetyenziswa njenge-oxidant ekwenzeni iidayi kunye nezinto eziphakathi.
Izimbiwa zeChromium
Kukho iintlobo ezingaphezu kwama-50 zeeminerali ezine-chromium ezifunyenwe kwindalo, kodwa uninzi lwazo lunomxholo ophantsi we-chromium kunye nokusasazwa okusasazekayo, okunexabiso eliphantsi lokusetyenziswa kwimizi-mveliso. Ezi minerali zine-chromium zeze-oxides, ii-chromates kunye nee-silicates, ukongeza kwii-hydroxides ezimbalwa, ii-iodates, ii-nitrides kunye nee-sulfides. Phakathi kwazo, iiminerali ze-chromium nitride kunye ne-chromium sulfide zifumaneka kuphela kwi-meteorites.
Njengentlobo yeminerali kwi-subfamily ye-chromium ore, i-chromite yeyona minerali ibalulekileyo ye-industrial ye-chromium. Ifomula yekhemikhali yethiyori yi-(MgFe)Cr2O4, apho umxholo we-Cr2O3 ubanga i-68%, kwaye i-FeO ibanga i-32%. Kwi-chemical composition yayo, i-trivalent cation ikakhulu yi-Cr3+, kwaye kuhlala kukho ii-isomorphic substitutions ze-Al3+, Fe3+ kunye ne-Mg2+, Fe2+. Kwi-chromite eveliswayo, inxalenye ye-Fe2+ idla ngokutshintshwa yi-Mg2+, kwaye i-Cr3+ ithathelwa indawo yi-Al3+ kunye ne-Fe3+ ukuya kumanqanaba ahlukeneyo. I-degree epheleleyo yokutshintshwa kwe-isomorphic phakathi kwezinto ezahlukeneyo ze-chromite ayihambelani. Ii-cations ezine-order coordination ikakhulu yi-magnesium kunye ne-iron, kunye nokutshintshwa okupheleleyo kwe-isomorphic phakathi kwe-magnesium-iron. Ngokwendlela yokwahlulahlula-hlula ezine, i-chromite inokwahlulwa ibe ngamaqela amane: i-magnesium chromite, i-iron-magnesium chromite, i-mafic-iron chromite kunye ne-iron-chromite. Ukongeza, i-chromite idla ngokuba nenani elincinci le-manganese, umxube ofanayo we-titanium, i-vanadium kunye ne-zinc. Ulwakhiwo lwe-chromite loluhlobo oluqhelekileyo lwe-spinel.
4. Umgangatho osemgangathweni we-chromium concentrate
Ngokweendlela ezahlukeneyo zokucubungula (ukwenziwa kweeminerali kunye ne-ore yendalo), i-chromium ore ye-metallurgy yahlulwe yaba ziintlobo ezimbini: i-concentrate (G) kunye ne-lump ore (K). Jonga itheyibhile engezantsi.
Iimfuno zomgangatho we-chromite ore kwi-metallurgy
Itekhnoloji yokuphucula i-ore yeChrome
1) Unyulo kwakhona
Okwangoku, ukwahlulwahlulwa kwamandla omhlaba kuthathe indawo ebalulekileyo ekuphuculeni i-chromium ore. Indlela yokwahlulwa kwamandla omhlaba, esebenzisa ukubekwa okukhululekileyo kwindawo enamanzi njengendlela esisiseko yokuziphatha, iseyeyona ndlela iphambili yokutyebisa i-chromium ore kwihlabathi liphela. Izixhobo zokwahlulwa kwamandla omhlaba yi-spiral chute kunye ne-centrifugal concentrator, kwaye uluhlu lobungakanani bezinto ezisetyenziswa ekucutshungulweni lubanzi kakhulu. Ngokubanzi, umahluko woxinano phakathi kweeminerali ze-chromium kunye neeminerali ze-gangue mkhulu kune-0.8g/cm3, kwaye ukwahlulwa kwamandla omhlaba kuyo nayiphi na i-particle size engaphezulu kwe-100um kunokwanelisa. Isiphumo. Amaqhuma amakhulu (100 ~ 0.5mm) ore ahlulwe okanye akhethwe kwangaphambili yi-heavy-medium beneficiation, eyindlela yokuzuza engabizi kakhulu.
2) Ukwahlulwa kwemagnethi
Ukwahlulwa kwemagnethi yindlela yokuzuza efezekisa ukwahlulwa kweeminerali kwindawo yemagnethi engalinganiyo ngokusekelwe kumahluko wemagnethi weeminerali kwi-ore. I-Chromite ineempawu zemagnethi ezibuthathaka kwaye inokwahlulwa ngabahluli bemagnethi abajikelezayo abaphezulu, abahluli bemagnethi abamanzi kunye nezinye izixhobo. Ii-coefficients ezithile zemagnethi ze-chromium minerals eziveliswa kwiindawo ezahlukeneyo ezivelisa i-chromium ore ehlabathini azifani kakhulu, kwaye zifana nee-coefficients ezithile zemagnethi ze-wolframite kunye ne-wolframite eziveliswa kwiindawo ezahlukeneyo.
Kukho iimeko ezimbini ekusebenziseni ukwahlukana kwemagnethi ukuze kufunyanwe i-chromium concentrate ephezulu: enye kukususa iiminerali ezinamandla zemagnethi (ikakhulu imagnethi) kwi-ore phantsi kwe-magnetic field ebuthathaka ukuze kwandiswe umlinganiselo we-ferrochrome, kwaye enye kukusebenzisa i-magnetic field enamandla. Ukwahlulwa kwe-gangue minerals kunye nokubuyiswa kwe-chromium ore (iiminerali zemagnethi ezibuthathaka).
3) Ukukhetha umbane
Ukwahlula ngombane yindlela yokwahlula i-chromium ore kunye ne-silicate gangue minerals ngokusebenzisa iipropati zombane zeeminerali, ezifana nomahluko kwi-conductivity kunye ne-dielectric constant.
4) Ukudada
Kwinkqubo yokwahlulwa komxhuzulane, i-chromite ore ecolekileyo (-100um) idla ngokulahlwa njengeentsalela, kodwa i-chromite yolu hlobo isenexabiso eliphezulu lokusetyenziswa, ngoko ke indlela yokutyibilika ingasetyenziselwa i-granular chromite ore entle ephantsi iyafunyanwa. Ukutyibilika kwe-chromium ore ene-20% ~40% Cr2O3 kwiintsalela kunye ne-serpentine, olivine, rutile kunye ne-calcium magnesium carbonate minerals njengeentsalela ze-gangue. I-ore iyacolwa kakuhle ukuya kwi-200μm, iglasi yamanzi, i-phosphate, i-metaphosphate, i-fluorosilicate, njl.njl. zisetyenziselwa ukusasaza nokuthintela intsalela, kwaye i-unsaturated fatty acid isetyenziswa njengesiqokeleli. Ukusasazeka kunye nokucinezelwa kwentsalela ye-gangue kubaluleke kakhulu kwinkqubo yokutyibilika. Ii-ion zesinyithi ezifana ne-iron kunye ne-lead zinokuvuselela i-chromite. Xa ixabiso le-pH ye-slurry lingaphantsi kwe-6, i-chromite ayizukudada kakhulu. Ngamafutshane, ukusetyenziswa kwe-reagent ye-flotation kukhulu, umgangatho we-concentrate awuzinzanga, kwaye izinga lokubuyisela liphantsi. I-Ca2+ kunye ne-Mg2+ ezinyibilikiswe kwiiminerali ze-gangue zinciphisa ukukhetha kwenkqubo ye-flotation.
5) Ukuphucula imveliso yeekhemikhali
Indlela yekhemikhali kukuphatha ngokuthe ngqo i-chromite ore ethile engenakwahlulwa ngendlela ebonakalayo okanye ixabiso lendlela ebonakalayo liphezulu. Umlinganiselo we-Cr/Fe we-concentrate eveliswa yindlela yekhemikhali uphezulu kunendlela eqhelekileyo ebonakalayo. Iindlela zekhemikhali ziquka: ukucocwa okukhethwayo, ukunciphisa i-oxidation, ukwahlulwahlulwa kokunyibilika, ukucocwa kwe-sulfuric acid kunye ne-chromic acid, ukunciphisa kunye nokucocwa kwe-sulfuric acid, njl. Ukudibanisa iindlela ze-physical-chemical kunye nonyango oluthe ngqo lwe-chromium ore ngeendlela zekhemikhali yenye yezona ndlela ziphambili zokuphucula i-chromite namhlanje. Iindlela zekhemikhali zinokukhupha i-chromium ngqo kwi-ore kwaye zivelise i-chromium carbide kunye ne-chromium oxide.
Ixesha lokuthumela: Epreli-30-2021