Ọdịdị nke chromium
Chromium, akara mmewere Cr, atomiki nọmba 24, ikwu atomic mass 51.996, bụ nke ngbanwe metal element nke otu VIB nke tebụl kemikal nke oge. Chromium metal bụ ahu-gbadoro anya cubic crystal, ọlaọcha-ọcha, njupụta 7.1g / cm³, agbaze ebe 1860 ℃, esi 2680 ℃, kpọmkwem okpomọkụ ike na 25 ℃ 23.35J / (mol·K), okpomọkụ nke vaporization 342.1kJ / mol, thermal conductivity 91.3 W / (m·K) (0-100 ° C), resistivity (20 ° C) 13.2uΩ · cm, na ezi n'ibu Njirimara.
Enwere valence ise nke chromium: +2, +3, +4, +5 na +6. N'okpuru ọnọdụ nke endogenous edinam, chromium bụ n'ozuzu +3 valence. Ngwakọta nwere + trivalent chromium bụ ihe kwụsiri ike. + Ngwakọta chromium isii, gụnyere nnu chromium, nwere ihe ndị na-eme ka ọ na-ekpo ọkụ. Ionic radii nke Cr3 +, AI3 + na Fe3 + yiri ya, n'ihi ya, ha nwere ike inwe ụdị dị iche iche. Na mgbakwunye, ihe ndị nwere ike dochie ya na chromium bụ manganese, magnesium, nickel, cobalt, zinc, wdg, ya mere a na-ekesa chromium na magnesium iron silicate mineral na ngwa ngwa.
Ngwa
Chromium bụ otu n'ime ọla ndị a na-ejikarị eme ihe na ụlọ ọrụ ọgbara ọhụrụ. A na-eji ya eme ihe na mmepụta nke igwe anaghị agba nchara na ụdị alloy dị iche iche n'ụdị ferroalloys (dị ka ferrochrome). Chromium nwere njiri mara nke siri ike, nke na-agaghị eyi akwa, na-eguzogide okpomọkụ yana nbibi. A na-eji ọla chrome eme ihe n'ọtụtụ ebe na metallurgy, ihe mgbagha, ụlọ ọrụ kemịkalụ na ụlọ ọrụ nrụpụta.
N'ime ụlọ ọrụ ọla, a na-ejikarị chromium ore agbaze ferrochrome na chromium dara. A na-eji Chromium dị ka ihe mgbakwunye nchara na-emepụta ụdị dị iche iche nke ike dị elu, nke na-eguzogide corrosion, na-eguzogide ọgwụ, okpomọkụ dị elu, na oxidation na-eguzogide ígwè pụrụ iche, dị ka igwe anaghị agba nchara, ígwè na-eguzogide acid, ígwè na-eguzogide okpomọkụ. bọọlụ agba ígwè, mmiri ígwè, ngwá ọrụ ígwè, wdg Chromium ike welie n'ibu Njirimara na-eyi iguzogide ígwè. A na-ejikarị chromium metal na-agbaze alloys pụrụ iche na cobalt, nickel, tungsten na ihe ndị ọzọ. Chrome plating na chromizing nwere ike ime ka ígwè, ọla kọpa, aluminum na ọla ndị ọzọ na-etolite a corrosion-eguzogide elu, nke na-egbuke egbuke ma mara mma.
N'ime ụlọ ọrụ refractory, chromium ore bụ ihe dị mkpa na-eme ka a na-eme brik chrome, brik chrome magnesia, ihe ndị na-emepụta ihe dị elu na ihe ndị ọzọ pụrụ iche na-emepụta ihe (chrome concrete). Ihe mgbakwasa chromium na-agụnyekarị brik nwere chrome ore na magnesia, magnesia-chrome clinker siri ike, brik magnẹsia-chrome a wụrụ awụ, nke a wụrụ awụ, ala nke ọma wee jikọta brik magnesia-chrome. A na-eji ha n'ọtụtụ ebe na ọkụ ọkụ na-emeghe, ọkụ induction, wdg. Metallurgical converter na rotary oven lining nke ciment ụlọ ọrụ, wdg.
N'ime ụlọ ọrụ ebe a na-emepụta ihe, chromium ore agaghị emekọrịta ihe na ihe ndị ọzọ na nchara a wụrụ awụ n'oge a na-agbapụta mmiri, nwere ọnụọgụ mgbasawanye ọkụ dị ala, na-eguzogide ntinye ígwè, ma nwee ọrụ oyi ka mma karịa zircon. Ore chrome maka ebe a na-emepụta ihe nwere ihe siri ike chọrọ na ihe mejupụtara kemịkalụ yana nkesa nha nha.
N'ime ụlọ ọrụ kemịkalụ, ihe kacha eji chromium eme ihe bụ imepụta ngwọta sodium dichromate (Na2Cr2O7·H2O), wee kwadebe ogige chromium ndị ọzọ maka iji ya na ụlọ ọrụ dịka pigmenti, textiles, electroplating, na imepụta akpụkpọ anụ, yana ihe na-akpali akpali. .
Ngwunye chromium ore ala nke ọma bụ ihe na-eme agba agba na mmepụta nke iko, ceramik na taịlị glazed. Mgbe a na-eji sodium dichromate emebie akpụkpọ anụ, protein (collagen) na carbohydrates dị na akpụkpọ anụ mbụ na-emeghachi omume na ihe ndị na-emepụta ihe na-emepụta ihe siri ike, nke na-aghọ ihe ndabere nke ngwaahịa akpụkpọ anụ. N'ime ụlọ ọrụ textile, a na-eji sodium dichromate mee ihe dị ka onye na-agba chaa chaa na ịcha akwa ákwà, nke nwere ike ijikọta ụmụ irighiri ihe nke ọma na ogige organic; Enwere ike iji ya mee ihe dị ka oxidant na-emepụta ihe eji esiji ákwà na etiti.
Chromium ịnweta
Enwere ihe karịrị ụdị mineral 50 nwere chromium nke achọpụtara na okike, mana ọtụtụ n'ime ha nwere ọdịnaya chromium dị ala na nkesa gbasasịrị, nke nwere ọnụ ahịa ụlọ ọrụ dị ala. Ihe ndị a nwere chromium nwere oxides, chromates na silicates, na mgbakwunye na hydroxides ole na ole, iodates, nitrides na sulfides. N'ime ha, chromium nitride na chromium sulfide mineral dị naanị na meteorites.
Dị ka ụdị ịnweta n'ime ezinụlọ chromium ore, chromite bụ naanị ihe dị mkpa nke ụlọ ọrụ mmepụta ihe nke chromium. Usoro kemịkalụ usoro iwu bụ (MgFe) Cr2O4, nke ọdịnaya Cr2O3 bụ 68%, yana FeO na-enweta 32%. N'ihe mejupụtara kemịkalụ ya, trivalent cation bụ Cr3+, na-enwekarị Al3+, Fe3+ na Mg2+, Fe2+ isomorphic nnọchi. Na chromite emepụtara n'ezie, Mg2+ na-edochi akụkụ nke Fe2+, na Cr3+ na-anọchi anya Al3+ na Fe3+ ruo ogo dị iche iche. Ogo zuru oke nke nnọchi isomorphic n'etiti akụkụ dị iche iche nke chromite anaghị agbanwe agbanwe. Usoro nhazi usoro anọ bụ magnesium na ígwè, yana ngbanwe isomorphic zuru oke n'etiti magnesium-iron. Dị ka usoro nkewa anọ si dị, chromite nwere ike kewaa n'ime akụkụ anọ: magnesium chromite, iron-magnesium chromite, mafic-iron chromite na iron-chromite. Na mgbakwunye, chromite na-enwekarị obere manganese, ngwakọta nke titanium, vanadium na zinc. Ọdịdị nke chromite bụ nke ụdị spinel nkịtị.
4. Ogo ọkọlọtọ nke chromium concentrate
Dị ka usoro nhazi dị iche iche (mineralization na eke ore), chromium ore maka metallurgy na-ekewa n'ime ụzọ abụọ: itinye uche (G) na akpụ ore (K). Lee okpokoro n'okpuru.
Ọdịmma chọrọ maka ọla chromite maka ọla
Teknụzụ uru Chrome ore
1) Nhọpụta ọzọ
Ka ọ dị ugbu a, ike ndọda nọ n'ọnọdụ dị mkpa na uru nke chromium ore. Usoro nkewa nke ike ndọda, nke na-eji akwa oyi akwa n'ime mmiri mmiri dị ka omume bụ isi, ka bụ usoro bụ isi maka ime ka chromium ore na-abawanye n'ụwa nile. The ike ndọda nkewa ngwá bụ a gburugburu chute na a centrifugal concentrator, na nhazi urughuru size nso bụ dịtụ obosara. N'ozuzu, njupụta dị iche n'etiti chromium mineral na gangue mineral dị ukwuu karịa 0.8g/cm3, na ike ndọda nke ihe ọ bụla urughuru size karịrị 100um nwere ike na-eju afọ. nsonaazụ nke. A na-ahazi ma ọ bụ buru ụzọ họpụta lumps (100 ~ 0.5mm) ore site n'erite uru dị arọ, nke bụ usoro ịba uru dị ukwuu.
2) nkewa magnetik
Nkewa magnetik bụ usoro uru nke na-achọpụta nkewa nke mineral na oghere magnetik na-abụghị nke na-adabere na ọdịiche magnetik nke mineral na ore. Chromite nwere ihe ndọta na-adịghị ike yana enwere ike ikewa ya site na mgbanaka vetikal high gradient magnetik separators, mgbochi mmiri efere magnetik na akụrụngwa ndị ọzọ. Ọnụ ọgụgụ nke ike ndọta kpọmkwem nke mineral chromium emepụtara na mpaghara chromium dị iche iche na-emepụta n'ụwa adịghị iche, ma yie kpọmkwem ọnụọgụ ihe ike ndọta nke wolframite na wolframite emepụtara na mpaghara dị iche iche.
Enwere ọnọdụ abụọ n'iji nkewa magnetik nweta ọkwa chromium dị elu: otu bụ iwepu ike magnetik mineral (karịsịa magnetite) na ore n'okpuru ebe ndọta na-adịghị ike iji mee ka ọnụọgụ nke ferrochrome dịkwuo elu, nke ọzọ bụ iji a. ike ndọta. Nkewa nke mineral gangue na mgbake nke chromium ore (mineral magnetik na-adịghị ike).
3) Nhọrọ eletrik
Nkewa eletrik bụ usoro nkewapụ chromium ore na silicate gangue mineral site na iji ihe ọkụ eletrik nke mineral, dị ka ọdịiche dị na conductivity na dielectric mgbe niile.
4) Flutation
Na usoro nke ike ndọda, ezi-grained (-100um) chromite ore na-atụfukarị dị ka ọdụ, ma chromite nke a size ka nwere nnukwu itinye n'ọrụ uru, n'ihi ya, a pụrụ iji usoro flotation maka obere ọkwa Granular chromite ore. agbakeela. Flotation nke chromium ore na 20% ~ 40% Cr2O3 na ọdụ na serpentine, olivine, rutile na calcium magnesium carbonate mineral dị ka gangue mineral. A na-eji mmanụ aṅụ nke ọma ruo 200μm, iko mmiri, phosphate, metaphosphate, fluorosilicate, wdg na-eji achụsasị na igbochi sludge, na unsaturated fatty acid na-eji dị ka onye nchịkọta. Mgbasa na nkwụsị nke sludge gangue dị ezigbo mkpa na usoro flotation. ion metal dị ka ígwè na lead nwere ike ime ka chromite rụọ ọrụ. Mgbe uru pH nke slurry dị n'okpuru 6, chromite agaghị esi n'elu mmiri. Na nkenke, flotation reagent oriri bụ nnukwu, na itinye uche ọkwa bụ ejighị n'aka, na mgbake ọnụego bụ ala. Ca2 + na Mg2+ gbazere site na mineral gangue na-ebelata nhọrọ nke usoro flotation.
5) uru kemịkalụ
Usoro kemịkalụ bụ ịgwọ ụfọdụ ore chromite nke enweghị ike ikewa ya site na usoro anụ ahụ ma ọ bụ ọnụ ahịa anụ ahụ dị oke elu. Oke Cr/F nke itinye uche na usoro kemịkalụ dị elu karịa nke usoro anụ ahụ nkịtị. Usoro kemịkalụ gụnyere: ịhọrọ leaching, mbelata oxidation, nkewa agbaze, sulfuric acid na chromic acid leaching, mbelata na sulfuric acid leaching, wdg. Nchikota nke usoro anụ ahụ-kemịkalụ na ọgwụgwọ kpọmkwem nke chromium ore site na usoro kemịkal bụ otu n'ime isi ihe. usoro na uru chromite taa. Ụzọ kemịkalụ nwere ike wepụ chromium ozugbo na ore wee mepụta chromium carbide na chromium oxide.
Oge nzipu: Eprel-30-2021