Ọdịdị nke chromium
Chromium, ihe nnọchianya nke ihe Cr, nọmba atọm 24, oke atọm dị n'otu 51.996, bụ nke ihe mgbanwe ígwè nke otu VIB nke tebụl oge nke ihe kemịkalụ. Chromium metal bụ kristal cubic nke dị n'etiti ahụ, ọcha-ọlaọcha, njupụta 7.1g/cm³, ebe agbaze 1860℃, ebe esi mmiri 2680℃, ikike okpomọkụ kpọmkwem na 25℃ 23.35J/(mol·K), okpomọkụ nke vaporization 342.1kJ/mol, ike okpomọkụ 91.3 W/(m·K) (0-100°C), ike iguzogide (20°C) 13.2uΩ·cm, nwere ezigbo ihe eji arụ ọrụ.
E nwere valensi ise nke chromium: +2, +3, +4, +5 na +6. N'okpuru ọnọdụ nke ihe na-eme n'ime ahụ, chromium na-abụkarị +3 valence. Ngwakọta nwere +trivalent chromium bụ ndị kacha sie ike. +Sixvalent chromium compounds, gụnyere nnu chromium, nwere ike ime ka oxidation sie ike. Radii ionic nke Cr3+, AI3+ na Fe3+ yiri ibe ha, yabụ ha nwere ike inwe ọtụtụ myirịta. Na mgbakwunye, ihe ndị enwere ike iji chromium dochie bụ manganese, magnesium, nickel, cobalt, zinc, wdg, yabụ chromium na-ekesa nke ukwuu na magnesium iron silicate minerals na ihe mgbakwunye minerals.
Ngwa
Chromium bụ otu n'ime ọla ndị a na-ejikarị eme ihe n'oge a. A na-ejikarị ya eme ihe n'ịmepụta ígwè anaghị agba nchara na ọtụtụ ígwè alloy dị iche iche n'ụdị ferroalloys (dịka ferrochrome). Chromium nwere njirimara nke siri ike, na-eguzogide iyi, na-eguzogide okpomọkụ na-eguzogide nchara. A na-ejikarị chrome ore eme ihe n'ọtụtụ ebe n'ịmepụta ígwè, ihe ndị na-anaghị eguzogide mmiri, ụlọ ọrụ kemịkalụ na ụlọ ọrụ mmepụta ihe.
N'ụlọ ọrụ ígwè, a na-ejikarị chromium ore agbaze ferrochrome na metal chromium. A na-eji chromium eme ihe dị ka ihe mgbakwunye ígwè iji mepụta ọtụtụ ígwè pụrụ iche dị ike, nke na-eguzogide nchara, nke na-eguzogide iyi, nke na-eguzogide okpomọkụ, na nke na-eguzogide oxidation, dị ka ígwè anaghị agba nchara, ígwè na-eguzogide acid, ígwè na-eguzogide okpomọkụ, ígwè na-agba bọọlụ, ígwè spring, ígwè ngwaọrụ, wdg. Chromium nwere ike ime ka ihe ndị dị n'ime igwe dịkwuo mma ma gbochie iyi nke ígwè. A na-ejikarị chromium metal agbaze alloys pụrụ iche na cobalt, nickel, tungsten na ihe ndị ọzọ. Mkpuchi chrome na chromizing nwere ike ime ka ígwè, ọla kọpa, aluminom na ọla ndị ọzọ mepụta elu na-eguzogide nchara, nke na-egbuke egbuke ma mara mma.
N'ụlọ ọrụ mmepụta ihe na-adịghị mma, chromium ore bụ ihe dị mkpa na-adịghị mma nke e ji eme brik chrome, brik chrome magnesia, ihe ndị na-adịghị mma nke ukwuu na ihe ndị ọzọ pụrụ iche na-adịghị mma (chrome concrete). Ihe ndị na-adịghị mma nke dabere na chrome gụnyere brik nwere chrome ore na magnesia, sintered magnesia-chrome clinker, brik melted magnesia-chrome brik, gbazere agbaze, a gwerie ya nke ọma ma tinyezie ya na brik magnesia-chrome. A na-ejikarị ha eme ihe n'ọkụ ọkụ mepere emepe, ọkụ induction, wdg. Ihe ntụgharị ígwè na ihe mkpuchi ọkụ rotary nke ụlọ ọrụ simenti, wdg.
N'ụlọ ọrụ mmepụta ihe, chromium ore agaghị ejikọta ya na ihe ndị ọzọ dị na ígwè agbaze agbaze n'oge a na-awụsa ya, ọ nwere obere mmụba okpomọkụ, ọ naghị eguzogide ịbanye na ígwè, ma nwee arụmọrụ oyi karịa zircon. Chrome ore maka nrụpụta ihe nwere ihe achọrọ siri ike na nhazi kemịkalụ na nkesa nha ihe.
N'ime ụlọ ọrụ kemịkalụ, ojiji chromium kacha mma bụ imepụta sodium dichromate (Na2Cr2O7·H2O), wee kwadebe ngwakọta chromium ndị ọzọ maka ojiji na ụlọ ọrụ dịka agba, ákwà, electroplating, na imepụta akpụkpọ anụ, yana ihe ndị na-akpali akpali.
Ntụ ntụ chromium nke a gwepịara nke ọma bụ ihe na-eme ka agba agba dịrị n'imepụta iko, seramiiki na taịlị glazed. Mgbe ejiri sodium dichromate mebie akpụkpọ anụ, protein (collagen) na carbohydrates dị na akpụkpọ anụ mbụ na-emeghachi omume na ihe kemịkalụ iji mepụta ihe siri ike, nke na-aghọ ntọala nke ngwaahịa akpụkpọ anụ. N'ụlọ ọrụ ákwà, a na-eji sodium dichromate eme ihe dị ka ihe na-eme ka ákwà dị nro, nke nwere ike itinye molekul agba na ihe ndị sitere n'okike; a pụkwara iji ya dị ka ihe na-eme ka ọ dị ọcha n'imepụta agba na ihe ndị dị n'etiti.
Chromium mineral
E nwere ihe karịrị ụdị mineral iri ise nwere chromium nke a chọpụtara n'okike, mana ọtụtụ n'ime ha nwere obere ọdịnaya chromium na nkesa gbasaara agbasa, nke nwere obere uru ojiji ụlọ ọrụ mmepụta ihe. Maịna ndị a nwere chromium bụ nke oxides, chromates na silicates, na mgbakwunye na ole na ole hydroxides, iodates, nitrides na sulfides. N'ime ha, a na-ahụ naanị mineral chromium nitride na chromium sulfide na meteorites.
Dịka ụdị mineral dị na ezinụlọ chromium, chromite bụ naanị mineral ụlọ ọrụ mmepụta ihe dị mkpa nke chromium. Usoro kemịkalụ nke echiche bụ (MgFe)Cr2O4, ebe ọdịnaya Cr2O3 dị 68%, FeO na-abụkwa 32%. N'ime ihe mejupụtara kemịkalụ ya, cation trivalent bụ Cr3+ karịsịa, enwerekwa mgbanwe isomorphic Al3+, Fe3+ na Mg2+, Fe2+. N'ime chromite emepụtara n'ezie, a na-ejikarị Mg2+ dochie akụkụ nke Fe2+, a na-ejikwa Al3+ na Fe3+ dochie Cr3+ ruo ogo dị iche iche. Ogo zuru oke nke mgbanwe isomorphic n'etiti ihe dị iche iche nke chromite anaghị agbanwe agbanwe. Cations nhazi usoro anọ bụ isi magnesium na iron, yana mgbanwe isomorphic zuru oke n'etiti magnesium-iron. Dịka usoro nkewa anọ si dị, enwere ike kewaa chromite n'ime obere otu anọ: magnesium chromite, iron-magnesium chromite, mafic-iron chromite na iron-chromite. Tinyere nke ahụ, chromite na-enwekarị obere manganese, ngwakọta yiri nke titanium, vanadium na zinc. Ọdịdị nke chromite bụ nke ụdị spinel nkịtị.
4. Ụkpụrụ ịdị mma nke mkpokọta chromium
Dịka usoro nhazi dị iche iche si dị (ịmepụta mineral na eke ore), a na-ekewa chromium ore maka metallurgy n'ụdị abụọ: concentrate (G) na lump ore (K). Lee tebụl dị n'okpuru.
Ihe achọrọ maka mma maka chromite ore maka ọrụ igwe
Teknụzụ maka imepụta ihe dị na chrome
1) Nhọpụta ọzọ
Ugbu a, nkewa ndọda nwere ọnọdụ dị mkpa n'ịba uru nke chromium ore. Usoro nkewa ndọda, nke na-eji akwa dị larịị n'ime mmiri dị ka omume bụ isi, ka bụ ụzọ bụ isi maka ime ka chromium ore baa ọgaranya n'ụwa niile. Ngwa nkewa ndọda bụ ihe na-agbagharị agbagharị na ihe na-eme ka centrifugal sie ike, oke nha mkpụrụ ndụ ihe nketa nhazi dịkwa obosara. N'ozuzu, ọdịiche njupụta dị n'etiti mineral chromium na mineral gangue karịrị 0.8g/cm3, nkewa ndọda nke nha mkpụrụ ndụ ihe nketa ọ bụla karịrị 100um nwere ike ịba uru. Nsonaazụ nke. A na-ahazi ma ọ bụ họrọ 100 ~ 0.5mm ore site na oke mmụba dị arọ, nke bụ usoro mmụba dị ọnụ ala.
2) Nkewa magnetik
Nkewa magnetik bụ ụzọ iji kewaa mineral n'ime ihe na-abụghị otu ụdị magnetik dabere na ọdịiche magnetik nke mineral dị na mineral ndị dị na mineral ndị ahụ. Chromite nwere ihe ndọta na-adịghị ike ma enwere ike kewaa ya site na mgbanaka kwụ ọtọ nke ihe ndọta na-agbanwe agbanwe, ihe ndọta na-ekewapụ efere mmiri na akụrụngwa ndị ọzọ. Ihe ndọta magnetik kpọmkwem nke mineral chromium emepụtara n'ọtụtụ ebe na-emepụta chromium ore n'ụwa adịghị iche nke ukwuu, ha yikwara ihe ndọta magnetik kpọmkwem nke wolframite na wolframite emepụtara n'ọtụtụ mpaghara.
E nwere ọnọdụ abụọ n'iji nkewa magnetik iji nweta chromium concentrate dị elu: otu bụ iwepụ mineral magnetik siri ike (karịsịa magnetite) n'ime ore ahụ n'okpuru ebe magnetik na-adịghị ike iji mee ka oke ferrochrome dịkwuo elu, nke ọzọ bụ iji ebe magnetik siri ike. Nkewa nke mineral gangue na mgbake nke chromium ore (mineral magnetik na-adịghị ike).
3) Nhọrọ eletriki
Nkewa eletriki bụ ụzọ isi kewaa mineral chromium ore na silicate gangue site na iji ihe eletriki nke mineral, dịka ọdịiche dị na conductivity na dielectric constant.
4) N'elu mmiri
N'usoro nkewa ike ndọda, a na-atụfukarị chromite dị nro (-100um) dị ka ọdụdụ, mana chromite nke nha a ka nwere uru ojiji dị elu, yabụ enwere ike iji usoro flotation mee ihe maka obere ọkwa dị mma nke Granular chromite ore. A na-enweta flotation nke chromium ore nwere 20% ~40% Cr2O3 na ọdụdụ na serpentine, olivine, rutile na calcium magnesium carbonate minerals dị ka gangue minerals. A na-agweri chromium ahụ nke ọma ruo 200μm, a na-eji iko mmiri, phosphate, metaphosphate, fluorosilicate, wdg iji gbasaa ma gbochie sludge, a na-ejikwa acid fatty acid na-enweghị afọ ojuju dị ka onye na-anakọta ihe. Mgbasa na mgbochi nke gangue sludge dị oke mkpa na usoro flotation. ion ígwè dị ka ígwè na lead nwere ike ime ka chromite rụọ ọrụ. Mgbe uru pH nke slurry dị n'okpuru 6, chromite agaghị efe efe. Na nkenke, oriri reagent flotation buru ibu, ọkwa concentration adịghị akwụsi ike, ọnụego mgbake dịkwa ala. Ca2+ na Mg2+ nke a gwakọtara site na mineral gangue na-ebelata nhọrọ nke usoro flotation.
5) Uru kemịkalụ
Usoro kemịkalụ bụ ịgwọ ụfọdụ chromite ore nke a na-apụghị ikewapụ site na usoro anụ ahụ ma ọ bụ ọnụ ahịa usoro anụ ahụ dị elu. Oke Cr/Fe nke concentrate nke usoro kemịkalụ mepụtara dị elu karịa nke usoro anụ ahụ nkịtị. Usoro kemịkalụ gụnyere: nhọrọ leaching, mbelata oxidation, nkewa agbaze, sulfuric acid na chromic acid leaching, mbelata na sulfuric acid leaching, wdg. Njikọta nke usoro anụ ahụ-kemikal na ọgwụgwọ kpọmkwem nke chromium ore site na usoro kemịkalụ bụ otu n'ime usoro bụ isi na chromite beneficiation taa. Usoro kemịkalụ nwere ike iwepụ chromium ozugbo na ore ahụ ma mepụta chromium carbide na chromium oxide.
Oge ozi: Eprel-30-2021