Bauxite iyinsimbi eyinhloko ye-aluminium futhi iyingxenye ebalulekile ekukhiqizeni imikhiqizo ehlukahlukene ye-aluminium. Le ndatshana ihlola lokho i-bauxite esetshenziselwa ukukwenza futhi ichaza inqubo yokukhipha i-aluminium ku-bauxite.
I-Bauxite ikakhulu isetshenziswa ukukhiqiza i-aluminium, okuwinsimbi ehluke-hluke esebenziswa kwez الصناعات ezahlukene. Nansi eminye yemikhiqizo eyinhloko kanye nezicelo ezitholakala ku-bauxite:
– Ukwakha: Kusetshenziselwa izinto zokwakha, njengezikhala zamafasitela, ukuphahla, nezimbobo.
– Ukuthutha: Kubalulekile ekwenzeni izimoto, izindiza, nezikebhe ngenxa yokukhanyiswa kwayo nokumelana nokugqwala.
– UkuPakisha: Kusetshenziswa ekukhiqizeni kwemaphakheji, ifoyili, nezinye izinto zokupakisha.
– Ezokuthenga: zitholakala kuzinto zikagesi, amadivayisi, nezimpahla zok cooks.
– I-refractories: Zisetshenziswa ezinhlelweni ezishisayo, njengezikhukhula nezikhukhula.
– Iseramikhi: Kubalulekile ekukhiqizeni imikhiqizo ye-seramikhi, kuhlanganise namathayela nemishini yokugeza.
– Imboni Yemikhiqizo Yamakhemikhali: Isetshenziswa ekucubunguleni amanzi nasekuphuculeni ezinqubweni ezahlukahlukene zamakhemikhali.
– Abaphuli: I-Bauxite isetshenziswa ekukhiqizeni abaphuli bokugaya nokuhlanganisa.
– Isamende: Isebenza njengengxenye ekwenzeni izinhlobo ezithile zezimende.
Ukukhipha i-aluminium ku-bauxite kuhilela izinyathelo eziningi, zonke eziyinqala ekutholeni i-aluminium ehlanzekile. Le nqubo ikakhulukazi ihlukaniswe ngezinyathelo ezimbili ezinkulu: Inqubo ye-Bayer kanye ne-Inqubo ye-Hall-Héroult.
Inqubo yeBayer iyindlela eyinhloko yokuhlanza ibauxite ukuze kukhiqizwe i-alumina (aluminium oxide), eyosetshenziswa ukukhiqiza insimbi ye-aluminium. Izinyathelo ezihilelekile zimi kanje:
– I-Bauxite iyacindezelwa futhi ibhujiswa ibe uthuli olunqamulelayo ukuze kwandiswe indawo yokukhanya ohlelweni lokukhipha.
- Ibhokisi eliphasayo lixutshwe nesixazululo esishisayo se-sodium hydroxide (NaOH), esixazulula okuqukethwe kwe-alumina, kushiya izinto ezingafaneleki emuva.
– Uxube lukhulelwa ukuba luhlale, bese kuhlukaniswa isixazululo esicacile esiqukethe i-alumina eyakhelwe ngaphakathi kusuka kuzinsalela ezingakhethiwe.
– Isisombululo se-alumina siyapholishwa futhi sihlanganyelwe namasongo e-aluminium hydroxide, okubangela ukuthi i-alumina iphume emsolution.
– I-alumina efakwe iyashiswa emathumeni okushisa ukuze kukhishwe amanzi, okuletha i-alumina engamanzi.
Inqubo ye-Hall-Héroult isetshenziselwa ukuguqula i-alumina ibe insimbi ye-aluminium ngokusebenzisa ukunciphisa kwe-electrolytic. Izinyathelo ziyi:
– I-Alumina iyaxutshwa ku-cryolite efudumele futhi ibekwa emsebenzini we-elektrolysis kwicell ye-reduction. Ijeneretha kagesi idlula esixazululweni, ibangela ama-ion e-aluminium ukuba athuthele kwi-cathode, lapho yehliswa khona ibe yinsimbi ye-aluminium.
– I-aluminium ephumelelayo iqoqwa ezansi kweseli futhi ikhishwe ngezikhathi.
– I-aluminium ekhishwe ibhujiswe ibe yizinkanyezi noma ezinye izimo ukuze iqhubele phambili kakhulu nokukhiqiza.
Bauxite idlala indima ebalulekile ekukhiqizeni i-aluminium, isebenza njengethuluzi eliyinhloko le-alumina. Inqubo yokukhipha, ehlanganisa izindlela ze-Bayer ne-Hall-Héroult, ibalulekile ekukhiqizeni insimbi ye-aluminium esetshenziswayo emikhakheni ehlukene. Ukuqonda lezi zinqubo kugcizelela ukubaluleka kwe-bauxite ekukhiqizeni kwanamuhla nasezinhlelweni zayo ezivamile.
