Njira ya Cyanidation mu Gold Ore Processing

Introduction

The ndondomeko ya cyanidation in kukonza golide ali ndi gawo lofunikira komanso losasinthika m'makampani opanga golide padziko lonse lapansi. Golide, wokhala ndi mtengo wake wautali monga chitsulo chamtengo wapatali, wakhala akufunidwa ndi anthu kwa zaka zikwi zambiri. Kuchokera pakukhala chizindikiro cha chuma ndi mphamvu m'zitukuko zakale mpaka kugwiritsa ntchito kwake masiku ano muzodzikongoletsera, zamagetsi, ndi ndalama, kufunikira kwa golide kukukulirakulirabe.

Njira yopangira cyanidation yakhala mwala wapangodya wa kuchotsa golide kwa zaka zopitirira zana. Kufunika kwake kwagona pakutha kutulutsa golide kuchokera kumitundu yosiyanasiyana ya miyala. Asanakhazikitse njira yopangira cyanidation, njira zochotsera golide nthawi zambiri zinali zogwira ntchito kwambiri, zosagwira ntchito bwino, komanso zowononga chilengedwe. Mwachitsanzo, kuphatikiza, njira yakale yopezera golidi, inali kugwiritsa ntchito mercury kumanga ndi tinthu tagolide. Komabe, njirayi inali ndi zovuta zazikulu, kuphatikizapo kuopsa kwa mercury komanso kuchepa kwa kuchira kwa mitundu ina ya miyala.

Mosiyana ndi zimenezi, ntchito ya cyanidation inasintha kwambiri migodi ya golide. Pogwiritsa ntchito mankhwala a cyanide, amatha kusungunula tinthu tating'ono ta golide, ngakhale tinthu tating'onoting'ono ta golide tating'onoting'ono, timagwira ntchito bwino kwambiri. Izi zimathandiza makampani opanga migodi kuti atenge golide kuchokera ku miyala yomwe poyamba inkaonedwa kuti ndi yopanda ndalama kuti ipangidwe. M'malo mwake, gawo lalikulu la golide wopangidwa padziko lonse lapansi masiku ano, akuyerekeza kupitilira 80%, amadalira njira ya cyanidation mwanjira ina. Kaya ndi migodi yayikulu yotseguka ku South Africa, United States, kapena migodi ya pansi pa nthaka ku Australia ndi China, njira yopangira cyanidation ndiyo njira yopezera golide. Kugwiritsiridwa ntchito kwake kwakukulu ndi umboni wa mphamvu zake komanso mphamvu zachuma m'dziko lovuta komanso lopikisana la migodi ya golide.

Kodi Cyanidation Process ndi chiyani

Njira ya cyanidation, pachimake, ndi njira yochotsera mankhwala yomwe imagwiritsa ntchito mankhwala apadera a ayoni a cyanide. Pankhani ya kukonza golide, mfundo zake zoyambiraCIPle imakhazikika mozungulira momwe zimakhalira pakati pa ma cyanide ions (CN^- ) ndi golide waulere.

Golide m'chilengedwe nthawi zambiri amakhalapo mwaulere, ngakhale atakulungidwa mkati mwa mchere wina. Maminolo ophatikizidwa akatsegulidwa, golide amawululidwa ngati golide woyambira. Ma cyanide ions ali ndi mgwirizano wamphamvu wa golidi. Pamene golide-wokhala ndi miyala ya golide imapezeka ku cyanide - yomwe ili ndi yankho, ma ion a cyanide amapanga zovuta zokhazikika ndi maatomu a golide. Chemical reaction imatha kuyimiridwa ndi equation yotsatirayi:

4Au + 8NaCN+O_2 + 2H_2O = 4Na[Au(CN)_2]+4NaOH. Pochita izi, pansi pakuchita kwa okosijeni, maatomu agolide amaphatikizana ndi ma cyanide ayoni kupanga golide wosungunuka - cyanide complex, sodium dicyanoaurate (Na[Au(CN)_2]). Kusintha kumeneku kumapangitsa kuti golidi, yemwe poyamba anali muzitsulo zolimba, asungunuke muzitsulo, ndikuzilekanitsa ndi zigawo zina zomwe sizinali golide.

Kunena zowona, njira ya cyanidation simalowa m'magawo akale a mineral processing koma imatchedwa hydrometallurgy. Kukonza mchere kumaphatikizapo njira zolekanitsa thupi monga kuphwanya, kugaya, kuyandama, ndi kulekanitsa mphamvu yokoka kuti alekanitse mchere wamtengo wapatali ku mchere wa gangue. Mosiyana ndi izi, hydrometallurgy imagwiritsa ntchito ma chemical reaction kuti ichotse zitsulo mu ores awo mu njira yamadzi. Njira ya cyanidation, ndi kudalira kwake pamachitidwe amankhwala kuti asungunuke golide mu cyanide - yomwe ili ndi yankho, momveka bwino ndi gawo la hydrometallurgy. Gulu ili ndilofunika chifukwa limasiyanitsa njira ya cyanidation kuchokera kuzinthu zina zakuthupi - zotengera ore - kukonza njira ndikuwunikira mankhwala ake - machitidwe - oyendetsedwa ndi chilengedwe pochotsa golide.

Mitundu ya Njira za Cyanidation: CIP ndi CIL

Mkati mwa njira zopangira cyanidation pochotsa golide, njira zazikulu ziwiri zikuwonekera: njira ya Carbon - in - Pulp (CIP) ndi Carbon - in - Leach (CIL).

Njira ya CIP imadziwika ndi ntchito yotsatizana. Choyamba, golide - zokhala ndi zamkati zamtengo wapatali zimadutsa m'zigawo. Munthawi imeneyi, miyalayi imasakanizidwa ndi cyanide - yomwe ili ndi yankho. Pansi pamikhalidwe yoyenera ya kupezeka kwa okosijeni, pH, ndi kutentha, golide mu ore amapanga chosungunuka chosungunuka ndi ma ion cyanide, monga tafotokozera mumayendedwe oyambira a cyanidation. Pambuyo pa leaching process, activated carbon imalowetsedwa mu zamkati. The activated carbon ndiye adsorbes golide - cyanide complex kuchokera yankho. Kulekanitsa uku kwa masitepe a leaching ndi adsorption kumapangitsa kuti pakhale njira yowongolera komanso yowongoleredwa nthawi zina. Mwachitsanzo, m'migodi momwe miyala yamtengo wapatali imakhala yosasunthika komanso malo otsetsereka amatha kusamalidwa bwino, ndondomeko ya CIP ikhoza kupeza ndalama zambiri zobwezeretsa golide.

Kumbali inayi, njira ya CIL ikuyimira njira yophatikizira. Munjira ya CIL, kutulutsa golide kuchokera ku ore ndi kutengeka kwa golide - cyanide complex ndi activated carbon zimachitika nthawi imodzi. Izi zimatheka powonjezera carbon activated mwachindunji mu akasinja leaching. Ubwino wa ndondomeko ya CIL uli pakugwiritsa ntchito bwino zida ndi nthawi. Popeza leaching ndi adsorption zimaphatikizidwa, palibe chifukwa chowonjezera zida kapena nthawi yosinthira zamkati pakati pa magawo a leaching ndi adsorption. Izi zimachepetsa kuchuluka kwa malo opangira ntchitoyo ndipo zitha kubweretsa kupulumutsa ndalama potengera ndalama zonse zogulira komanso zowonongera zogwirira ntchito. Mwachitsanzo, m'ntchito zazikulu za migodi komwe kutulutsa kumakhala kofunikira kwambiri, njira ya CIL imatha kuthana ndi miyala yochulukirapo munthawi yaifupi, kukulitsa luso lopanga.

M'zaka zaposachedwa, njira ya CIL yakhala ikuvomerezedwa kwambiri ndi zomera za cyanidation padziko lonse lapansi. Kuthekera kwake kugwiritsa ntchito bwino zida zopangira kumapereka mwayi wopitilira njira ya CIP nthawi zambiri. Chikhalidwe chosalekeza cha ndondomeko ya CIL chimapangitsanso kuti pakhale ntchito yokhazikika, yosasinthasintha pang'ono mu khalidwe la mankhwala omaliza. Kuphatikiza apo, kuchepa kwa masitepe mu CIL kumatanthauza kuti pali mwayi wocheperako wolakwa kapena kutayika panthawi yosinthira zinthu pakati pa magawo osiyanasiyana a ndondomekoyi. Komabe, kusankha pakati pa CIP ndi CIL sikophweka nthawi zonse. Zimatengera zinthu zosiyanasiyana monga mtundu wa miyala, kukula kwa migodi, ndalama zogulira ndalama, komanso zofunikira pazachilengedwe komanso zowongolera. Migodi ina ingakondebe ndondomeko ya CIP chifukwa cha chikhalidwe chake chomveka bwino komanso chogawanika, chomwe chingakhale chosavuta kuyendetsa nthawi zina.

Zofunikira zazikulu mu Njira ya Cyanidation

Kugaya Fineness

Kufewetsa kugaya kumagwira ntchito yofunika kwambiri pakugwira ntchito kwa cyanidation. Popeza mphamvu ya cyanidation imadalira kuthekera kovumbulutsa golide wotsekedwa, kugaya mosamala ndikofunikira. Muzomera za carbon - in - pulp (CIP), kufunikira kogaya kuti ore alowe mu ntchito ya cyanidation ndizovuta kwambiri. Nthawi zambiri, kuchuluka kwa particles ndi kukula kwa -0.074mm kuyenera kufika 80 - 95%. Kwa migodi ina komwe golidi amafalitsidwa mu 浸染 - monga chitsanzo, ulusi wogaya umakhala wovuta kwambiri, ndi gawo la -0.037mm tinthu tating'ono timafunika kukhala pamwamba pa 95%.

Kuti apeze mphero yabwino yotere, ntchito yopera imodzi nthawi zambiri imakhala yosakwanira. Nthawi zambiri, awiri - siteji kapena atatu - siteji akupera ndi zofunika. Mwachitsanzo, mu mgodi waukulu wa golide ku Western Australia, miyalayi imakhala ndi magawo awiri. Gawo loyamba ntchito lalikulu - mphamvu mpira mphero kuchepetsa tinthu kukula kumlingo, ndiyeno mankhwala ndi zina pansi wachiwiri - siteji analimbikitsa mphero. Izi Mipikisano siteji akupera ndondomeko akhoza pang'onopang'ono kuchepetsa tinthu kukula kwa ore, kuonetsetsa kuti particles golide bwinobwino poyera ndipo angathe kuchita bwino ndi cyanide njira pa ndondomeko cyanidation. Ngati ulusi wogaya sunakwaniritsidwe, tinthu tating'ono ta golide sitingawonekere bwino, zomwe zimapangitsa kuti pakhale kusungunuka kosakwanira panthawi ya cyanidation komanso kuchepa kwakukulu kwa kubweza golide.

Kupewa Cyanide Hydrolysis

Mankhwala a cyanide omwe amagwiritsidwa ntchito kwambiri popanga cyanidation, monga potaziyamu cyanide (KCN), Sodium cyanide (NaCN), ndi calcium cyanide (Ca (CN)_2 ), onse ndi mchere wa maziko amphamvu ndi ofooka asidi. Mu njira yamadzimadzi, amakhala tcheru ku hydrolysis zimachitikira. Zotsatira za hydrolysis Sodium Cyanide akhoza kuimiridwa ndi equation:

NaCN + H_2O\kumanjaleftharpoons HCN+NaOH. Monga hydrogen cyanide (HCN) imakhala yosasunthika, njira iyi ya hydrolysis imayambitsa kuchepa kwa cyanide ions (CN ^-) mu zamkati, zomwe zimawononga cyanidation reaction.

Kuti athetse vutoli, njira yabwino kwambiri ndiyo kuonjezera kuchuluka kwa ayoni a hydroxide ( OH ^-), omwe ali ofanana ndi kuonjezera pH phindu la yankho. M'mafakitale, laimu (CaO ) ndizomwe zimagwiritsidwa ntchito kwambiri komanso zotsika mtengo zosinthira pH. Laimu akawonjezeredwa ku yankho, amachitira ndi madzi kupanga calcium hydroxide (Ca (OH)_2 ), yomwe imalekanitsa kumasula ayoni a hydroxide, motero amawonjezera pH mtengo. Kachitidwe ka mandimu ndi madzi ndi: , CaO + H_2O=Ca(OH)_2 & Ca(OH)_2\rightleftharpoons Ca^{2 + }+2OH^- .

Komabe, mukamagwiritsa ntchito laimu kuti musinthe pH mtengo, ndikofunikira kuzindikira kuti laimu alinso ndi flocculation effect. Kuonetsetsa kuti laimu amamwazikana mofanana ndipo amatha kugwira ntchito yake bwino, nthawi zambiri amawonjezeredwa panthawi yopera. Mu mgodi wa golidi ku South Africa, laimu amawonjezeredwa ku mphero yopera. Izi osati amalola laimu kuti mokwanira wothira ore slurry komanso amapezerapo mwayi amphamvu makina mukubwadamuka mu mpira mphero kuonetsetsa kuti laimu wogawana anagawira mu slurry, mogwira kuteteza hydrolysis wa cyanide ndi kukhalabe khola ndende ya ayoni cyanide mu wotsatira ndondomeko cyanidation. Nthawi zambiri, pamachitidwe a carbon - in - pulp, pH yamtengo wapakati pa 10 - 11 imapezeka kuti ikupereka zotsatira zabwino.

Kuwongolera Kukhazikika kwa Pulp

Kuchuluka kwa zamkati kumakhudza kwambiri kulumikizana kwa golide ndi cyanide komanso pakati pa golide - cyanide complex ndi activated carbon. Ngati zamkati ndende ndi okwera kwambiri, ndi particles zambiri precipitate pamwamba pa adamulowetsa mpweya, kulepheretsa ogwira adsorption wa golide - cyanide zovuta ndi adamulowetsa mpweya. Komano, ngati zamkati ndende ndi otsika kwambiri, particles amakonda kukhazikika mosavuta, ndi kusunga yoyenera pH mtengo ndi cyanide ndende, kuchuluka kwa reagents ayenera kuwonjezeredwa, amene kumawonjezera kupanga mtengo.

Kupyolera muzochita zopanga, zatsimikiziridwa kuti pakuchotsa golide - mu - zamkati, kuchuluka kwa zamkati kwa 40 - 45% ndi kuchuluka kwa cyanide kwa 300 - 500 ppm ndikoyenera. Mwachitsanzo, m'malo opangira golide ku Nevada, USA, kusunga kuchuluka kwa zamkati mkati mwamtunduwu kwapeza golide wokwera kwambiri. Komabe, poganizira kuti gawo lomaliza la ntchito yogaya magawo awiri mpaka atatu nthawi zambiri amakhala pansi pa 20%, asanalowe mu opaleshoni, zamkati zimafunika kukulitsa.

The thickening ntchito zambiri ikuchitika mu thickener. Mfundo ya thickener ndi kugwiritsa ntchito sedimentation zotsatira kulekanitsa olimba particles ndi madzi mu zamkati, potero kuwonjezera ndende ya zamkati. M'mafakitale amakono a golide, zokometsera zapamwamba zimagwiritsidwa ntchito nthawi zambiri. Izi thickeners okonzeka ndi patsogolo flocculation ndi sedimentation kulamulira machitidwe, amene angathe mwamsanga ndi mogwira kuonjezera zamkati ndende kwa mlingo wofunika kwa wotsatira cyanidation leaching ntchito, kuonetsetsa kupita patsogolo bwino kwa ndondomeko cyanidation ndi mkulu - dzuwa m'zigawo golide.

Cyanidation Leaching Mechanism

Aeration ndi Oxidant

Njira ya cyanidation ndi njira ya aerobic, ndipo izi zitha kuwonetsedwa momveka bwino kudzera mu equation yamankhwala. Chotsatira chachikulu cha kusungunuka kwa golide mu ndondomeko ya cyanidation ndi 4Au + 8NaCN + O_2 + 2H_2O = 4Na[Au(CN)_2] +4NaOH . Kuchokera ku equation iyi, zikuwonekeratu kuti mpweya (O_2 ) umagwira ntchito yofunika kwambiri pakuchitapo kanthu. Panthawi yopanga, kuyambitsa okosijeni kumatha kufulumizitsa kwambiri kuchuluka kwa leaching. Izi ndichifukwa choti okosijeni amatenga nawo gawo pakuchita kwa redox, faCILkutenthetsa makutidwe ndi okosijeni a golide ndi kusakanikirana kwake kotsatira ndi ayoni a cyanide. Mwachitsanzo, m'mafakitale ambiri opangira golide, mpweya woponderezedwa umalowetsedwa mu cyanide - yomwe ili ndi yankho. Mpweya womwe uli mumlengalenga umapereka malo ofunikira oxidizing kuti zomwe zikuchitika ziyende bwino.

Kuphatikiza pa aeration, kuwonjezera koyenera kwa ma oxidizing agents kumathanso kupititsa patsogolo njira ya leaching. Hydrogen peroxide (H_2O_2) ndi mankhwala omwe amagwiritsidwa ntchito kwambiri popanga cyanidation. hydrogen peroxide ikawonjezedwa, imatha kupereka mitundu yowonjezereka ya okosijeni, yomwe imatha kulimbikitsa kutulutsa kwa golide ndi kusungunuka kwa golide - wokhala ndi mchere. Zochita za hydrogen peroxide ndi golide pamaso pa cyanide zitha kuimiridwa ndi equation: 2Au+4NaCN+H_2O_2 = 2Na[Au(CN)_2]+2NaOH . Izi zikuwonetsa kuti hydrogen peroxide imatha kulowa m'malo mwa gawo lina la okosijeni pakuchita kwa cyanidation, ndipo munthawi zina, imatha kuyambitsa kuthamanga kwachangu.

Komabe, ndikofunikira kuzindikira kuti kuchuluka kwa okosijeni wambiri kumatha kukhala ndi zotsatirapo zoyipa. Pamene kuchuluka kwa okosijeni wothandizila kwambiri, kungayambitse makutidwe ndi okosijeni a ayoni cyanide. Mwachitsanzo, hydrogen peroxide imatha kuchitapo kanthu ndi ayoni a cyanide kupanga ayoni a cyanate (CNO ^-). Zomwe zidachitika ndi izi: CN^-+H_2O_2 = CNO^-+H_2O . Mapangidwe a ion cyanate amachepetsa kuchuluka kwa ayoni a cyanide mu yankho, lomwe ndi lofunikira pakuphatikiza ndi golide. Zotsatira zake, kutulutsa bwino kwa golide kumatha kuchepetsedwa, ndipo njira yonse yopangira ikhoza kusokonezedwa. Choncho, mlingo wa oxidizing agents uyenera kuyang'aniridwa mosamala kuti uwonetsetse kuti njira ya cyanidation ikugwira ntchito bwino.

Mlingo wa Reagent

Mwachidziwitso, momwe zimakhalira pakati pa golidi ndi cyanide zimakhala ndi ubale weniweni wa stoichiometric. Kuchokera ku mankhwala equation 4Au + 8NaCN + O_2 + 2H_2O = 4Na[Au(CN)_2]+4NaOH, tikhoza kuwerengera kuti 1 mole ya golide (Au) imafuna 2 moles ya cyanide ions (CN^-) kuti ikhale yovuta. Pankhani ya unyinji, pafupifupi 1 gramu ya golidi imafuna pafupifupi 0.5 magalamu a cyanide monga chochitira leaching. Kuwerengeraku kumapereka chidziwitso chofunikira cha kuchuluka kwa ma reagents ofunikira munjira ya cyanidation.

Komabe, pakupanga kwenikweni, zinthu zimakhala zovuta kwambiri chifukwa cha kupezeka kwa mchere wina mu golide wonyamula miyala. Maminolo monga siliva (Ag), mkuwa (Cu), lead (Pb), ndi zinc (Zn) amathanso kuchitapo kanthu ndi ayoni a cyanide. Mwachitsanzo, mkuwa ukhoza kupanga mitundu yosiyanasiyana yamkuwa - cyanide. Mmene mkuwa uli ndi cyanide ukhoza kufotokozedwa ngati Cu^{2 + }+4CN^-=[Cu(CN)_4]^{2 - } . Zochita zotsutsanazi zimadya kuchuluka kwa cyanide, ndikuwonjezera mlingo wofunikira.

Choncho, mu ntchito yothandiza, kutsimikiza kwa mlingo wa reagent sikungangotengera mawerengedwe ongoyerekeza. M'malo mwake, iyenera kusinthidwa molingana ndi mlingo womaliza wa leaching. Pamene ore katundu kusintha, mosalekeza kutsatira ndi kusintha kwa reagent mlingo ndi zofunika. Kawirikawiri, zimaonedwa kuti ndizomveka kuti mlingo weniweni wa cyanide ukhale 200 - 500 nthawi zambiri kuposa mtengo wowerengedwa. Kupatuka kosiyanasiyana kumeneku kumapangitsa kusiyanasiyana kwa kapangidwe ka miyala yamtengo wapatali komanso kusagwirizana pakati pa mchere wosiyanasiyana. Mwa kuyang'anitsitsa mlingo wa leaching ndi kusintha mlingo wa reagent moyenerera, ndondomeko yochotsa golide ikhoza kukwaniritsa bwino komanso phindu lachuma.

Multi-siteji Leaching ndi Leaching Time

Kuonetsetsa kukhazikika kwa ntchito yosalekeza ndikusunga ma ayoni okhazikika a cyanide mu yankho, ma multi-stage leaching amagwiritsidwa ntchito. M'magawo ambiri a leaching system, zamkati za ore zimadutsa motsatizana ndi matanki angapo a leaching. Thanki iliyonse imathandizira kusungunuka kwa golide mosalekeza komanso kukonza ndende ya cyanide - ion. Pamene zamkati zimayenda kuchokera ku thanki ina kupita kwina, golide - cyanide complex imapangidwa pang'onopang'ono ndipo ma ion aulere a cyanide amasinthidwa kuti atsimikizire kuti zomwe zikuchitika zikupitirizabe bwino. Njira yokhazikikayi imathandizira kuwongolera kusinthasintha kulikonse komwe kumachitika ndipo imapereka malo okhazikika a njira ya cyanidation. Mwachitsanzo, pakuchita migodi yayikulu ya golide ku Western Australia, njira ya magawo asanu imagwiritsidwa ntchito. Gawo loyamba limayamba kutulutsa golide, ndipo magawo otsatirawa amachotsa golide ndikusunga bwino kwa cyanide - ion, zomwe zimapangitsa kuti golide azikhala wokwera komanso wosasunthika.

Nthawi yotulutsa ndi chinthu chofunikira kwambiri pakuzindikira kuchuluka kwa tanki yotulutsa. Komabe, palibe njira yosavuta komanso yapadziko lonse yowerengera nthawi ya leaching. Chomera chilichonse cha carbon - in - pulp (CIP) kapena carbon - in - leach (CIL) chiyenera kudalira deta yoyesera kuti idziwe nthawi yoyenera yotulutsa. Izi ndichifukwa choti nthawi ya leaching imakhudzidwa ndi zinthu zingapo, kuphatikiza mtundu ndi kapangidwe ka miyala, kuchuluka kwa ma reagents, kutentha, komanso kuchuluka kwa chipwirikiti. Mwachitsanzo, mu fakitale yokonza golide ku South Africa, kuyezetsa kwakukulu kwa ma labotale - sikelo ndi sikelo - sikelo kunachitika fakitale isanamangidwe. Mayeserowa adakhudza kusiyanasiyana kwa nthawi yotulutsa ndikuwunika kuchuluka kwa golide pamikhalidwe yosiyanasiyana. Kutengera ndi zotsatira zoyeserera, nthawi yoyenera yotulutsa idatsimikiziridwa kukhala maola 24 pamtundu wa miyala yamtengo wapatali yomwe imakonzedwa pachomeracho.

Ngati chomera chimadalira mwachimbulimbuli pazomwe zidachitika popanda kuyezetsa bwino, chikhoza kukumana ndi kulephera kupanga. Mwachitsanzo, migodi yaing'ono ya golide m'dera lina idayesa kugwiritsa ntchito nthawi yochotsa mgodi woyandikana nawo ngati chiwongolero popanda kuganizira za kusiyana kwa zinthu zawo. Chotsatira chake, golide - leaching mlingo unali wochepa kwambiri kuposa momwe amayembekezera, ndipo mtengo wopangira unakula kwambiri chifukwa cha kuchepa kwachangu komanso kufunikira kowonjezera mowa wa reagent. Choncho, kutsimikiza kolondola kwa nthawi ya leaching kupyolera mu deta yoyesera ndikofunikira kuti ntchito yabwino ya cyanidation - based gold - extraction plant.

Ntchito za Post cyanidation

Pamene golidi - wokhala ndi activated carbon, wotchedwa carbon loaded, akafika pa golidi - adsorption level yoposa 3000g/t, amaonedwa kuti njira yonse ya carbon - in - pulp adsorption yatha. Komabe, kupezeka kwa zonyansa zambiri monga mkuwa ndi siliva mu ore kumatha kukhudza kwambiri mphamvu ya adsorption ya activated carbon. Zonyansazi zimatha kupikisana ndi golide wa malo otsatsa pa carbon activated, zomwe zimapangitsa kulephera kwa kalasi yodzaza - carbon kuti ifike pa zomwe zikuyembekezeka. Pamene carbon activated sichitha kutsatsa golide bwino, imatengedwa kuti ndi yodzaza.

Kwa saturated activated carbon, njira zingapo zingagwiritsidwe ntchito kupeza golide. Njira imodzi yodziwika bwino ndi desorption ndi electrolysis. Mu njira ya desorption, yankho lamankhwala limagwiritsidwa ntchito kuvula golide - cyanide complex kuchokera ku saturated activated carbon. Mwachitsanzo, mu njira ya kutentha kwambiri komanso kuthamanga kwapamwamba, mpweya wodzaza mpweya umayikidwa mu dongosolo la desorption ndi zinthu zinazake. Powonjezera ma anions omwe amatengeka mosavuta ndi kaboni, Au(CN)_2 ^- zovuta zimachotsedwa pamlengalenga. Njira yochitirayi imaphatikizapo kusinthana kwa golide - cyanide complex ndi ma anions owonjezera, zomwe zimapangitsa golide kutulutsidwa mu yankho. Pambuyo pa desorption, yankho, lomwe limadziwika kuti njira yapakati, imakhala ndi ayoni ambiri agolide.

Njira yothetsera mimba ndiye imapanga electrolysis. Mu cell electrolysis, mphamvu yamagetsi imagwiritsidwa ntchito. Ma ion golide mu yankho amakopeka ndi cathode, komwe amapeza ma electron ndipo amachepetsedwa kukhala golide wazitsulo. Njirayi ikhoza kuyimiridwa ndi equation: Au^+ + e^-\rightarrow Au . Golide amaunjikana pa cathode mu mawonekedwe a matope golide, amene angathe kukonzedwanso kupeza mkulu - chiyero golide.

M'madera omwe golide amapangidwa kwambiri, njira ina ndiyo kugulitsa carbon yodzaza. Izi zitha kukhala zosankha zopindulitsa chifukwa makampani ena apadera ali ndi zida zogwirira ntchito yowonjezereka ya kaboni yodzaza. Ali ndi ukatswiri ndi zida zochotsera golide kuchokera ku kaboni wodzaza, ndipo makampani opanga migodi atha kupeza ndalama pogulitsa kaboni wodzaza ku mabungwewa.

Njira ina yosavuta ndiyo kuyaka. Mpweya wonyamulidwa ukatenthedwa, zida za organic za carbon activated ndi oxidized ndi kuwotchedwa, pamene golide amakhalabe mu zotsalira mu mawonekedwe a golide aloyi, wotchedwa dore golide. Golide wa Dore nthawi zambiri amakhala ndi golide wambiri komanso zonyansa zina. Pambuyo pa kuyaka, golide wa dore amatha kuyengedwanso kudzera munjira monga kusungunula ndi kuyeretsa kuti apeze zinthu zagolide zoyera kwambiri zomwe zimakwaniritsa miyezo yogwiritsidwa ntchito pamalonda m'makampani opanga zodzikongoletsera, zamagetsi, ndi zogulitsa.

Ubwino ndi Kuipa kwa Njira ya Cyanidation

ubwino

1. Mtengo Wobwezeretsa Wapamwamba: Chimodzi mwazabwino kwambiri za njira ya cyanidation ndi kuchira kwake kwakukulu. Kwa golide wokhala ndi okosijeni - wokhala ndi quartz - vein ores, mukamagwiritsa ntchito njira ya carbon - in - pulp (CIP) kapena carbon - in - leach (CIL), chiwopsezo chonse chochira chimatha kufikira 93%. M'zinthu zina zokongoletsedwa bwino, chiwopsezo chochira chingakhale chokwera kwambiri. Kubwezeretsa kwakukulu kumeneku kumatanthauza kuti makampani opanga migodi akhoza kutulutsa gawo lalikulu la golide wopezeka mu miyalayi, kukulitsa phindu lachuma kuchokera ku ntchito ya migodi. Mwachitsanzo, mu mgodi waukulu wa golidi ku United States, poyang'anira mosamalitsa magawo azinthu monga kugaya fineness, ndende ya zamkati, ndi mlingo wa reagent, golide wobwezeretsa ndondomeko ya cyanidation wakhala akusungidwa mozungulira 95% kwa nthawi yaitali, yomwe ndi yokwera kwambiri kuposa njira zina zambiri zochotsera golide.

2. Kugwiritsa Ntchito Kwambiri: Njira ya cyanidation ndi yoyenera mitundu yosiyanasiyana ya golide - yokhala ndi miyala. Imatha kugwira bwino osati oxidized ores golide komanso ena sulfide - okhala ndi golide. Kaya golidiyo ali m'malo omasuka kapena atakulungidwa mkati mwa mchere wina, ndondomeko ya cyanidation nthawi zambiri imatha kusungunula golideyo mothandizidwa ndi chithandizo choyenera ndi ndondomeko yoyenera. Mwachitsanzo, m'migodi ina ku South America komwe miyalayi imakhala ndi mchere wosakaniza wa sulfide ndi oxidized golide, njira ya cyanidation yagwiritsidwa ntchito bwino. Pambuyo makutidwe ndi okosijeni bwino chisanadze mankhwala a mchere sulfide, ndondomeko cyanidation akhoza kukwaniritsa golide wokhutiritsa - m'zigawo zotsatira, kusonyeza kusinthasintha ake amphamvu ku mitundu yosiyanasiyana ya ore.

3. Ukadaulo Wokhwima: Ndi mbiri yazaka zopitilira zana, njira ya cyanidation yakhala ukadaulo wokhwima kwambiri pantchito yamigodi ya golide. Zida ndi njira zogwirira ntchito zimakhazikitsidwa bwino, ndipo pali zambiri zomwe zimasonkhanitsidwa ndi deta. Kukhwima uku kumatanthauza kuti ndondomekoyi ndi yosavuta kugwiritsa ntchito ndikuwongolera. Makampani amigodi akhoza kudalira miyezo ndi malangizo omwe alipo kale kuti apange, kumanga, ndi kugwiritsa ntchito zomera za cyanidation. Mwachitsanzo, kamangidwe ka matanki a cyanidation leaching, kusankha kwa carbon activated for adsorption, ndi kulamulira mlingo wa reagent onse ali ndi ndondomeko ndi njira zokhazikika. Zomera zaposachedwa za cyanidation zitha kuyamba mwachangu ndikufika pakupanga kokhazikika, kuchepetsa kuopsa kokhudzana ndi kutengera ukadaulo watsopano.

kuipa

1. Kuopsa kwa Cyanide: Chotsalira chodziwika bwino cha njira ya cyanidation ndi poizoni wa cyanide. Cyanide mankhwala, monga sodium cyanide ndi potaziyamu cyanide, ndi zinthu zapoizoni kwambiri. Ngakhale cyanide yaying'ono imatha kuwononga kwambiri thanzi la munthu komanso chilengedwe. Ngati cyanide - yomwe ili ndi mayankho itayikira panthawi ya migodi, imatha kuwononga nthaka, magwero a madzi, ndi mpweya. Mwachitsanzo, m'mbiri yakale ya ngozi zamigodi, kutayikira kwa cyanide - komwe kumakhala ndi madzi otayira kunayambitsa kufa kwa zamoyo zambiri zam'madzi m'mitsinje ndi nyanja zapafupi, komanso kuwopseza thanzi la anthu am'deralo. Kukoka mpweya, kuyamwa, kapena kukhudzana ndi khungu ndi cyanide kungayambitse zizindikiro zoopsa zakupha mwa anthu, monga chizungulire, nseru, kusanza, komanso zowopsa kwambiri, zimatha kupha. Chifukwa chake, chitetezo chokhazikika komanso chitetezo cha chilengedwe chimafunikira pakugwiritsa ntchito cyanide, zomwe zimawonjezera zovuta komanso mtengo wantchito yamigodi.

2. Zovuta komanso Zotsika mtengo - chithandizo: Ntchito zochizira pambuyo pa cyanidation ndizovuta kwambiri ndipo zimafunikira ndalama zambiri. Pambuyo golide - kukhala activated carbon kufika machulukitsidwe, njira monga desorption, electrolysis, kapena kuyaka amafunika kupeza golide woyera. Njira za desorption ndi electrolysis zimafuna zida zapadera ndi ma reagents amankhwala. Mwachitsanzo, mu njira yowonongeka, kutentha kwapamwamba ndi kupanikizika kwapamwamba kungakhale kofunikira, ndipo kugwiritsa ntchito mankhwala opangira mankhwala a desorption kumafunikanso kuyang'aniridwa mosamala kuti golide abwezeretsedwe ndi kubwezeretsanso ma reagents. Kuphatikiza apo, kukonza zotsalira za zinyalala ndi madzi otayira omwe amapangidwa panthawi yopangira chithandizo ndizovuta. Zotsalira za zinyalala zitha kukhalabe ndi kuchuluka kwa cyanide ndi zinthu zina zovulaza, ndipo madzi otayira ayenera kusamitsidwa kuti akwaniritse miyezo yokhazikika yotaya zachilengedwe, zomwe zimapangitsa kuti pakhale kukwera mtengo kwa njira yonse ya cyanidation.

3. Kumva Kuwonongeka kwa Ore: Njira ya cyanidation imakhudzidwa kwambiri ndi zonyansa zomwe zili mu miyalayi. Maminolo monga mkuwa, siliva, lead, ndi zinki amatha kuchitapo kanthu ndi cyanide, kudya ma reagents ambiri a cyanide. Izi osati kumawonjezera mtengo wa reagents komanso amachepetsa dzuwa la m'zigawo golide. Mwachitsanzo, pamene mkuwa uli wochuluka, mkuwa ukhoza kupanga mkuwa wolimba - cyanide complexes, kupikisana ndi golidi wa cyanide ions. Zotsatira zake, kuchuluka kwa cyanide komwe kumapezeka popanga golidi kumachepetsedwa, ndipo kutsika kwa golide kumatha kukhudzidwa kwambiri. Nthawi zina, njira zowonjezera zothandizira zisanachitike zingafunikire kuchotsa kapena kuchepetsa zotsatira za zonyansazi, zomwe zimawonjezera zovuta ndi mtengo wa migodi.

Kutsiliza

Pomaliza, njira ya cyanidation ndiukadaulo wofunikira kwambiri pantchito yamigodi ya golide. Kuchulukira kwake kuchira, kugwiritsa ntchito kwambiri, komanso ukadaulo wokhwima zapangitsa kuti ikhale njira yayikulu yochotsera golide padziko lonse lapansi. Zathandiza kutulutsa golide kuchokera kumitundu yosiyanasiyana ya ore, zomwe zathandizira kwambiri pakupanga golide wapadziko lonse lapansi.

Komabe, njira ya cyanidation ilibe zovuta zake. Kuopsa kwa cyanide kumawopseza kwambiri thanzi la anthu komanso chilengedwe. Njira zotetezeka komanso zoteteza zachilengedwe ziyenera kutsatiridwa kuti cyanide isatayike ndikuwonetsetsa kuti cyanide ili ndi madzi oyipa ndi zotsalira za zinyalala zoyenera. Kuphatikiza apo, zovuta komanso zotsika mtengo zopangira chithandizo, komanso kukhudzidwa kwazinthu zonyansa za ore, kumawonjezera zovuta komanso mtengo wopangira golide.

Kuyang'ana m'tsogolo, tsogolo la njira ya cyanidation pakukonza miyala ya golide liyenera kupangidwa ndi kupita patsogolo kwaukadaulo. Kupanga njira zochepetsera zachilengedwe komanso zogwira mtima za cyanidation, monga kugwiritsa ntchito m'malo mwa poizoni wa cyanide, ndi njira yodalirika. Ukadaulo wamagetsi ndi wanzeru nawonso utenga gawo lofunikira kwambiri. Ukadaulo uwu ukhoza kupititsa patsogolo kupanga bwino, kuchepetsa ngozi zobwera chifukwa cha zolakwika za anthu, ndikuwongolera kugwiritsa ntchito bwino zinthu. Mwachitsanzo, makina odzipangira okha amatha kuwongolera mlingo wa reagent, kuchuluka kwa zamkati, ndi magawo ena ofunikira, kuwonetsetsa kuti ntchito yokhazikika komanso yothandiza kwambiri.

Kuonjezera apo, kufufuza kwa matekinoloje atsopano okhudzana ndi cyanidation, monga bio - cyanidation kapena kuphatikiza kwa cyanidation ndi njira zina zomwe zikubwera, zingathe kupereka njira zatsopano zothetsera mavuto omwe alipo. Ndi luso lopitilira komanso kuwongolera, njira ya cyanidation imatha kukhalabe ndi ukadaulo wotsogola pakukonza miyala ya golide pomwe ikukhala yokhazikika komanso yosamalira zachilengedwe. Pamene kufunikira kwa golidi kumakhalabe kolimba m'mafakitale osiyanasiyana, kupititsa patsogolo ndi kukhathamiritsa kwa njira ya cyanidation kuyenera kukhala kofunikira pakutukuka kwanthawi yayitali kwa migodi ya golide.