Te Tukanga me te Hangarau Tukatuka Nikara
He konganuku rautaki te nikara, ā, kei te piki haere te hiranga o tana mahi i roto i ngā ahumahi hou. Haunga te whakamahinga hei hanga i te maitai kore waikura, he wāhanga matua anō hoki te nikara i roto i te whanaketanga o ngā pākahiko waka hiko, ngā koranu motuhake mō te ahumahi rererangi, tae atu ki te whakakikorua hiko. I te pikinga ake o te tono o te ao, kei te tere haere te whanaketanga o ngā tukanga me ngā hangarau tukatuka nikara ki te whakaputa hua me ngā taumata motuhake, te whai huatanga teitei, me te pānga taiao e whakahaeretia ana. Ka matapakihia e tēnei tuhinga ngā wāhanga whānui me ngā hangarau matua i roto i te tukatuka nikara, mai i te keri ki te whakamahine.
Ngā momo o te Nikara: Laterite me te Sulfide
I te nuinga o te wā, e rua ngā momo matua o te nikara: te nikara laterite me te nikara sulfide. Ka hangaia te nikara laterite mai i te huarere o ngā toka ultramafic i ngā rohe werawera, ā, ka kitea i te nuinga o te wā tata ki te mata. He maha ngā wā kei roto i te laterite te nikara i roto i ngā kohuke pēnei i te limonite me te saprolite. I taua wā, ka hangaia te nikara sulfide mā roto i ngā tukanga magmatic, ā, kei roto i te nikara he nikara i roto i ngā kohuke sulfide pēnei i te pentlandite. Ko ngā rerekētanga o ēnei āhuatanga kohuke te mea nui hei whakatau i te tikanga tukatuka e whakamahia ana.
He māmā ake te whakanikoniko i ngā konganuku whanariki mā roto i ngā tukanga whakamānu, engari he uaua ake ngā konganuku laterite nā te mea ka marara te nikara i roto i te hanganga o ngā kohuke waikura/waihāora, nō reira he maha ka tukatukahia mā te pyrometallurgical (whakarewa) me te hydrometallurgical pēhanga teitei rānei.
Ngā Wāhanga Tīmatanga: Te Keri me te Whakarite i te Ore
Ka tīmata te tukanga tukatuka nikara mā te keri, mā te whakamahi i ngā tikanga keri tuwhera, keri whenua rānei, i runga i te hohonu me te momo o te putunga. I muri i te keri, ka haria te konganuku ki tētahi whare tukatuka hei mahi i ngā mahi whakarite, arā, ko ēnei:
1. Te kuru: Te whakaiti i te rahi o te konganuku kia māmā ake ai te whakahaere me te tukatuka.
2. Huri: Ka whakaputa i ngā rahi matūriki angiangi hei whakanui ake i te tukunga o ngā kohuke whai hua.
3. Te tātari me te whakarōpūtanga: Te wehewehe i ngā rahi matūriki kia rite ki ngā hiahia o te tukanga e whai ake nei.
4. Te Whakamaroke: Ina koa mō te konganuku laterite he nui te wai, he mea nui te whakamaroke i mua i te tukanga pyrometallurgical.
He nui te pānga o te wāhanga whakarite ki te whai huatanga o ngā tukanga e whai ake nei. Ko te rahi o te matūriki, te nui o te makuku, me te ōritetanga o te konganuku ka whakatau i te whakamahinga pūngao me te tere whakaora o te nikara.
Hangarau Tukatuka Kohatu Nikara
Mō ngā konganuku nikara whanariki, ko te huarahi tukatuka tino noa ko te whakakotahitanga o te kukū kohuke me te whakarewa.
1. Te Whakarewatanga (Te Whakarewatanga Huka)
Ko te whakapūmau he tukanga wehewehe i ngā kohuke i runga i ngā āhuatanga o te mata. Ka konatunatua te konganuku kua mira ki te wai, ki ngā matū matū, me te hau. I te nuinga o te wā ka nui ake te ātete o ngā kohuke whanariki ki te wai i muri i te tāpiri i tētahi kaikohi, nō reira ka piri ki ngā mirumiru hau ka ara ake hei pahuka. Ka whakahokia mai tēnei pahuka hei matū kukū nui-nikara, ko ngā toenga rauemi ka waiho hei paru.
Ko te painga o te whakapūngā ko tōna kaha ki te whakanui ake i te nui o te nikara i mua i te urunga ki te wāhanga whakarewa, ā, mā reira ka whakaitihia te kawenga pūngao i te tukanga e whai ake nei.
2. Te Whakarewa me te Hurihanga
Kātahi ka rewa te nikara kukū i roto i te oumu hei whakaputa i te nikara matte—he wāhanga wai whanariki kei roto ko te nikara, te parahi, me te rino. Ko te mahi e whai ake nei ko te huri hei whakakōkī i te rino me te whanariki, kia nui ake ai te nikara i roto i te matte. Ka taea te tukatuka anō i te hua whakamutunga hei nikara parakore, hei hua takawaenga rānei pērā i te nikara whanariki mō ngā pākahiko.
3. Te Whakamahinga Matatau
Ka taea te whakamahine mā te hikohiko, mā te waiwhakarewa rānei. I ētahi whare, ka whakarewahia te matte, ka wehea hoki mā te whakamahi i te whakarewa whiriwhiri, te tango whakarewa, me ngā tikanga whakapūmau hei whakaputa i tētahi hua kounga teitei.
Hangarau Tukatuka Kohatu Nikara Laterite
He wāhanga nui o ngā rahui nikara o te ao te kohuke laterite, inā koa i ngā rohe pārūrū. He uaua ake te tukatuka i a rātou, ā, e rua ngā huarahi matua e whakamahia ana: te pyrometallurgy me te hydrometallurgy.
1. Pyrometallurgy: RKEF mō te Ferronickel, te NPI rānei
Ko tētahi o ngā hangarau tino rongonui mō te laterite ko te Rotary Kiln Electric Furnace (RKEF). He maha ngā wā ka whakamahia tēnei tukanga hei hanga ferronickel, Nickel Pig Iron rānei (NPI), he rauemi mata mō te umanga kowiri tira.
Kei roto i ngā wāhanga:
– Te whakamaroke me te whakapūkara i roto i te oumu hurihuri: Ka whakaiti i te nui o te makuku me te tango i ngā mea pupuhi. Ka whakamahanahia te konganuku i te wā e konatunatua ana ki te whakaiti (te nuinga o te waro) me te rerenga motuhake.
– Te whakarewa i roto i te oumu hiko: Ka rewahia te konganuku kua whakawerahia i ngā pāmahana teitei hei wehe i te konganuku (te ranunga rino-nikara) mai i te para.
– Te whakamahine hua: Ka makahia, ka tukatukahia rānei te konganuku rewa hei hua e ai ki ngā whakaritenga.
Ko ngā painga o te RKEF ko tōna pumau hangarau me te pai o te hua mō te maitai kore waikura. Heoi, he nui te pūngao e hiahiatia ana mō tēnei tukanga, ā, he pai ake mō ngā konganuku saprolite he nui te ihirangi nikara.
2. Te Whakarewa Wai: HPAL mō te Waikawa Waikawa Whakaranu (MHP)
Mō te konganuku limonite—he iti ake te kounga engari he nui—ko te hangarau hydrometallurgical te mea e pai ana, inā koa ko te HPAL (High Pressure Acid Leach).
I roto i te HPAL, ka konatunatua te konganuku ki te waikawa (ko te waikawa whanariki te tikanga) ka tukatukahia i roto i te autoclave i te pāmahana me te pēhanga teitei. Ka rewa te nikara me te konutai i roto i te otinga, kātahi ka wehea mai i te toenga totoka. Kātahi ka taea te whakapūpū i te nikara me te konutai hei hua takawaenga pēnei i:
– MHP (Whakaurunga Waikawa Whakaranu): Whakaurunga waikawa whakaranu nikara-kopara.
– MSP (Whakaurunga Pūkawa Whakaranu): Whakaurunga pūkawa whakakawa.
Kātahi ka taea te whakamahine anō i te hua MHP, MSP rānei hei nikara whanariki me te konutai whanariki mō ngā rauemi pākahiko.
Ko te painga o HPAL he taea te tukatuka i te konganuku iti te kounga me te whakaputa hua e tika ana mō te mekameka tuku pākahiko. Ko ētahi o ngā wero ko te hiahia mō ngā rauemi taputapu ātete-waikura, te whakahaere toenga, te uaua o te mahi, me te whakamahinga o ngā matū.
3. Te Whakarewa i te Āhuarangi me ngā Tukanga Rerekē
Haunga te HPAL, kei reira anō te tangohanga mai i te hau i ngā pēhanga iti iho, he puhoi ake te tere whakarewa engari he māmā ake. Kei te whanake haere hoki ngā rangahau mō te whakamahinga o te tangohanga koiora (te whakamahi i ngā moroiti) me ngā tukanga pyrometallurgical me te hydrometallurgical hei whakapai ake i te ōhanga.
Ngā Hua Waenga me ngā Hua Whakamutunga: Mai i te NPI ki te Nickel Sulfate
Ehara i te mea he nikara parakore tonu ngā hua tukatuka nikara. I runga anō i ngā hiahia o te ahumahi, ka uru pea ki ngā hua tukatuka:
– NPI me te ferronickel: Ko te tikanga mō te maitai kore waikura.
– Nikara mā: He hua takawaenga mai i te kaihanga whakarewa ka taea te whakapai ake.
– MHP/MSP: Hua takawaenga mō te whakamahine nikara-kopara, inā koa mō ngā pākahiko.
– Te nikara whanariki (NiSO₄): He rauemi mata nui mō ngā katote pākahiko.
– Nikara konganuku parakore: Mō ngā koranu motuhake me ētahi atu whakamahinga hangarau.
Ko te kōwhiringa o te ara tukatuka ka whakatauhia e te momo konganuku, te wātea o te pūngao, te utu o ngā matū hohe, te hanganga, ngā ture taiao, me ngā hua ūnga.
Ngā Āhuatanga Taiao me te Whai Huatanga Pūngao
He wero taiao kei roto i te tukatuka nikara e hiahia ana kia whakahaerea nuitia, tae atu ki ngā tukunga hau mai i te pyrometallurgy, te nui o te whakapaunga pūngao, te whakamahinga o ngā waikawa i roto i te hydrometallurgy, me te whakahaere i ngā paru me te para. Ko te whāinga o te hangarau hou he whakapai ake i te whai huatanga o te pūngao, te whakamahi i te wera para, te rongoā i te wai e rere ana, me te whakau i ngā toenga mō te haumaru mō te wā roa.
I ētahi whenua, mā te whakatinanatanga o ngā paerewa taiao ka akiaki i ngā ahumahi ki te whakamahi i ngā pūtake pūngao ma, ki te whakaiti i ngā tukunga waro, me te whakarite kia nui ake te kawenga mō te keri me te whakaora whenua.
Te Katinga
He nui te pānga o te momo o te oro e tukatukahia ana me te hua whakamutunga e hiahiatia ana ki te tukatuka me te hangarau o te nikara. Ko ngā oro whanariki ka tukatukahia mā te whakapūmau me te whakarewa hei whakaputa nikara matte, ā, hei whakamutunga, he nikara parakore, he hua matū rānei. I taua wā, he maha ngā wā ka tukatukahia ngā oro laterite mā te RKEF (Refined Iron Oxide Processing) hei whakaputa ferronickel/NPI, HPAL rānei hei whakaputa MHP/MSP, e tika ana mō ngā tono pākahiko. I te pikinga ake o te hiahia mō te nikara mō te whakawhiti pūngao, ko te auahatanga i roto i te hangarau tukatuka me ngā mahi pumau kua whakapaitia ko ngā mea matua hei āwhina i te umanga nikara kia tupu me te whakaiti i tōna pānga ki te taiao.
