Njira Zoyeretsera Zitsulo Zamtengo Wapatali monga Golide ndi Siliva
Kuyenga zitsulo zamtengo wapatali monga golide (Au) ndi siliva (Ag) ndi njira yofunika kwambiri yowonjezera chiyero cha zitsulo kuchokera ku miyala, zinthu zosungunuka, kapena zinthu zobwezerezedwanso (monga zodzikongoletsera zakale, zinyalala zamagetsi, ndi zinyalala zamafakitale). Chifukwa cha kufunika kwawo pazachuma komanso kugwiritsidwa ntchito kwambiri mu zodzikongoletsera, zamagetsi, mankhwala, ndi ndalama, miyezo yoyera golide ndi siliva nthawi zambiri imafunika kukhala yokwera kwambiri, mwachitsanzo, 99,9% (3N) kapena 99,99% (4N). Kuti tikwaniritse izi, njira zosiyanasiyana zoyengera zimagwiritsidwa ntchito, kusankhidwa kutengera mtundu wa zinthu zopangira, kuchuluka kwa zodetsa, kukula kwa kupanga, ndalama, ndi chitetezo ndi zinthu zachilengedwe.
1. Magawo Onse Oyeretsera: Kuchokera ku Concentrate mpaka ku Pure Metal
Kawirikawiri, kuyenga golide ndi siliva kumafuna magawo angapo. Choyamba ndi kukonzekera zinthu: kuphwanya, kupukuta, kulekanitsa zinthu (monga mphamvu yokoka kapena kuyandama), ndi kuumitsa. Kenako zinthuzo zimakonzedwa kudzera mu kuchotsa (kuchotsa kapena kusungunula) kuti zichotse chitsulo chamtengo wapatali kuchokera pamwala kapena pa alloy matrix. Pambuyo pake, kuyenga kumachitika kuti zichotse zonyansa zilizonse zotsala mpaka kalasi yomwe mukufuna ifike.
Kuyenga golide ndi siliva kungachitike kudzera mu pyrometallurgy (kutentha/kusungunula), hydrometallurgy (mankhwala ozikidwa pa yankho), kapena electrometallurgy (electrolysis). Mwachizolowezi, mafakitale nthawi zambiri amaphatikiza njira zingapo zogwirira ntchito bwino komanso zinthu zapamwamba.
2. Kuyeretsa pogwiritsa ntchito Pyrometallurgy (Kusungunula ndi Kugawa)
a) Kulekanitsa kusungunula ndi kusungunula zinyalala (Kusungunula)
Mu miyala ina kapena zinthu zina zokhuthala, zitsulo zamtengo wapatali zimasungunuka mwa kuzisungunula ndi madzi. Cholinga chake ndikupanga chitsulo chamadzimadzi kapena chosalimba chomwe chimanyamula golide/siliva, pomwe zinthu zodetsedwa zimasamutsidwira ku slag. Gawoli limakhala ngati "kuchuluka koyamba," koma nthawi zambiri silipanga chitsulo choyera kwambiri.
b) Chikho cholekanitsa siliva/golide ndi lead
Njira yakale yomwe imagwiritsidwabe ntchito kwambiri ndi cupellation, yomwe imaphatikizapo kutentha alloy ya lead (Pb) yokhala ndi chitsulo chamtengo wapatali pansi pa mikhalidwe yopangira okosijeni. Lead imasungunuka kukhala PbO2 (litharge) ndipo imalowa muzinthu zokhala ndi mabowo (cupel), pomwe golide ndi siliva wamtengo wapatali kwambiri zimasiyidwa. Njirayi ndi yothandiza pa zitsanzo zina ndipo imagwiritsidwanso ntchito poyesa, koma kugwiritsidwa ntchito kwake pamlingo wamakono wamakampani kumachepetsedwa ndi mavuto a utsi ndi kufunikira kowongolera njira.
c) Kugawa: Kulekanitsa Golide ndi Siliva
Ngati golide ndi siliva zilipo ngati aloyi (monga mu zamagetsi kapena zodzikongoletsera), njira yolekanitsira imafunika kuti ipatule ziwirizi. Mwachikhalidwe, kulekanitsa kumaphatikizapo kusungunula siliva ndi asidi winawake, zomwe zimapangitsa kuti golide asasungunuke. Kuchokera pamenepo, silivayo imatha kubwerezedwanso, ndipo golideyo amakonzedwanso kuti akhale woyera.
Pyrometallurgy ndi yolimba posamalira zinthu zambiri komanso zovuta, koma kugwiritsa ntchito mphamvu ndi kasamalidwe ka mpweya woipa ndizovuta kwambiri.
3. Kuyeretsa pogwiritsa ntchito Hydrometallurgy (Kusungunuka Kosankha ndi Kugwa kwa Mvula)
Hydrometallurgy imagwiritsa ntchito njira zamagetsi posungunula golide/siliva kenako n’kuilekanitsa ndi zinthu zodetsedwa. Ubwino wake ndi monga kusankha bwino zinthu komanso kugwiritsa ntchito zinthu zosiyanasiyana zopangira, kuphatikizapo zinthu zobwezerezedwanso.
a) Kusakaniza kwa Golide (Kusakaniza)
Njira imodzi yodziwika bwino yochotsera golide ndi cyanidation, momwe golide amasungunuka mu cyanide solution pamaso pa mpweya, ndikupanga solvent complex. Golide akangolowa mu solution, kuchira kumachitika kudzera mu:
– Kulowetsedwa kwa mpweya wopangidwa ndi activated carbon (CIP/CIL): golide amamangiriridwa ku kaboni, kenako amatulutsidwa (lution) ndikusungunuka.
– Kuchuluka kwa zinki (Merrill–Crowe): golide amachotsedwa mu yankho pogwiritsa ntchito zinki, yoyenera kupangidwa ndi mayankho omveka bwino okhala ndi golide winawake.
Pambuyo pochira, golide nthawi zambiri amafunika kuyengedwa kwambiri (mwachitsanzo, pomusungunula mu mipiringidzo ya dore, kenako nkuiyeretsa ndi electro-chemical).
Chofunika kudziwa: kugwiritsa ntchito cyanide kumayendetsedwa bwino chifukwa cha poizoni wake, kotero malo amakono amagwiritsa ntchito njira zotsekedwa, kuchotsa zinyalala m'thupi, komanso kuyang'anira bwino chilengedwe.
b) Kusungunuka kwa Siliva: Nitrate ndi Thiosulfate
Siliva imapanga mchere/zovuta zosungunuka mosavuta. Mu njira zina, siliva imatha kusungunuka ngati siliva nitrate m'malo enaake, kenako nkubwezeretsedwanso ndi mvula (monga AgCl) kapena kuchepetsedwa kukhala chitsulo. Njira zina zimaphatikizapo machitidwe ovuta monga thiosulfate pansi pa mikhalidwe yolamulidwa. Kusankha reagent kumakhudzidwa ndi mtundu wa zinthu ndi zodetsa zomwe zilipo.
c) Kusankha Mvula ndi Kuyeretsa Mayankho
Chitsulo chikasungunuka, yankho nthawi zambiri limakhala ndi zinthu zosafunika (mkuwa, chitsulo, zinki, nikeli). Njira zomwe zimagwiritsidwa ntchito ndi izi:
- Kusintha kwa pH kuti kupangitse kuti ma hydroxide ayambe kuipitsidwa.
- Kuwonjezera zinthu zoyambitsa mabakiteriya kuti apange mankhwala enaake osasungunuka.
- Kusinthana kwa ma ion kuti agwire zinthu zachitsulo mosankha.
- Kutulutsa zosungunulira m'mapulojekiti ena a mafakitale.
Kupambana kwa hydrometallurgy kuli mu kulamulira kwa chemistry ya yankho: pH, redox potential, kutentha, ndi kuchuluka kwa reagent.
4. Kuyeretsa Ma Electro: Miyezo Yapamwamba Yoyera
Kuti apeze chiyero chapamwamba kwambiri, mafakitale amagwiritsa ntchito kwambiri kuyeretsa kwa electrolytic. Mfundo yaikulu ndi yakuti: zitsulo zosayera zimagwiritsidwa ntchito ngati ma anode, omwe amasungunuka panthawi ya electrolysis. Zitsulo zoyera zimakhazikika pa cathode, pomwe zonyansa zina zimatsala kapena zimalowa mu matope.
a) Njira ya Wohlwill ya Golide
Wohlwell ndi njira yoyeretsera golide yomwe imatha kupanga golide woyera kwambiri (mpaka 99,99%). Dori ya golide (golide wosalala) imagwiritsidwa ntchito ngati anode, ndipo golide woyera umatuluka pa cathode. Zonyansa monga siliva nthawi zambiri zimapanga precipitate yosasungunuka ndipo zimasonkhanitsidwa ngati anode slime, yomwe imakonzedwa kuti ibwezeretse zitsulo zina zamtengo wapatali (kuphatikiza siliva ndi platinamu).
Ubwino wa njirayi ndi khalidwe lapamwamba kwambiri la mankhwala, koma imafuna kulamulira bwino ma electrolyte ndi zomangamanga.
b) Njira ya Moebius ya Siliva
Pa siliva, njira yodziwika bwino yoyeretsera electro ndi njira ya Moebius. Siliva ya anode imasungunuka ndikugwa ngati makhiristo asiliva enieni pa cathode. Zonyansa monga golide sizisungunuka ndipo zimasonkhanitsidwa ngati matope a anode, zomwe zimapangitsa kuti zigwiritsidwe ntchito padera. Njirayi ndi yothandiza ndipo imagwiritsidwa ntchito kwambiri m'mafakitale oyeretsera siliva.
Kukonzanso magetsi kumapambana popanga "bullion grade" kapena "zitsulo zabwino," koma kumafuna magetsi, kuwongolera yankho, ndi kusamalira matope a anode okhala ndi zitsulo zamtengo wapatali komanso zonyansa zoopsa.
5. Kuyeretsa pogwiritsa ntchito zipangizo zobwezerezedwanso (Kukumba Migodi m'mizinda)
Pamene zinyalala zamagetsi zikuchulukirachulukira, kuyeretsedwa kwa golide ndi siliva kuchokera ku "migodi ya m'mizinda" kukukulirakulira. Ma circuit board (PCBs), zolumikizira, ndi zinthu zina zimakhala ndi golide/siliva wochepa koma wofunika kwambiri. Njirayi nthawi zambiri imaphatikizapo:
1. Kukonza makina: kusanja, kuphwanya, kulekanitsa mphamvu yamagetsi ya maginito/eddy.
2. Kuchotsa zinthu mosankha: choyamba kusungunula chitsulo choyambira (monga mkuwa), kenako kuchotsa golide/siliva.
3. Kuyeretsa kwina: kuyeretsa kosankha kapena kuyeretsa kwamagetsi.
Mavuto akuluakulu obwezeretsanso zinthu ndi kuuma kwa zipangizo (mapulasitiki, ma resin, zinthu zoletsa moto zopangidwa ndi brominated) komanso kuthekera kopanga zinyalala zoopsa. Chifukwa chake, njira zamakono zobwezeretsanso zinthu zimagogomezera machitidwe otsekedwa, kusefa, ndi kukonza zinyalala mosamala.
6. Kuwongolera Ubwino: Kuyesa Zomwe Zili M'kati ndi Chitsimikizo
Zinthu zopangidwa ndi golide ndi siliva weniweni nthawi zambiri zimatsimikiziridwa ndi njira zowunikira monga:
- Kuyesa moto (kuti mudziwe bwino kuchuluka kwa golide/siliva).
– XRF (X-ray fluorescence) kuti mufufuze mwachangu kapangidwe kake.
- ICP-OES/ICP-MS kuti iwonetse molondola kwambiri pamlingo wochepa wa kuipitsidwa.
Kuphatikiza apo, bullion pamsika wogulitsa ndalama nthawi zambiri imafuna satifiketi, masitampu a fakitale (mint/refinery), manambala a seri, ndi miyezo ina yoyera.
7. Chitetezo ndi Zachilengedwe
Kuyeretsa zitsulo zamtengo wapatali kumaika makampaniwo pangozi ya mankhwala owononga komanso oopsa, komanso kutulutsa mpweya woipa. Njira zabwino ndi izi:
- Makina opumira mpweya ndi chotsukira mpweya.
- Kuchiza madzi otayira ndi kuchotsa poizoni m'thupi.
- Kugwiritsa ntchito PPE ndi njira zadzidzidzi.
- Kuwunika zachilengedwe ndi kutsatira malamulo.
Njira zamakono zimalimbikitsanso zinthu zoteteza chilengedwe, kugwiritsa ntchito mphamvu moyenera, komanso kubwezeretsa mankhwala kuchokera mu ndondomekoyi.
Mapeto
Njira zoyeretsera golide ndi siliva zimaphatikizapo kuphatikiza kwa pyrometallurgy, hydrometallurgy, ndi electrometallurgy, ndipo electrorefining ndi yofunika kwambiri kuti munthu akhale woyera kwambiri. Kusankha njira kumadalira zinthu zomwe zimachokera—kaya ndi miyala, zinthu zosungunuka, kapena zinyalala zobwezerezedwanso—komanso zolinga zoyera ndi zogwiritsira ntchito bwino ndalama. Munthawi yamakono yamakampani, kuyeretsera sikumangofuna zitsulo zamtengo wapatali zapamwamba komanso chitetezo, kutsatira malamulo, komanso udindo wa chilengedwe. Ndi kupita patsogolo kwaukadaulo, njira zoyeretsera zikupitilizabe kupita ku machitidwe osankha bwino, osawononga mphamvu, komanso okhazikika popanda kuwononga mtundu wa golide ndi siliva wopangidwa.
