Kupititsa patsogolo Mitengo ya Golide ndi Silver Leaching mu Njira ya Oxygen-Rich Cyanidation ndi Ammonia

Introduction

Kuchotsa golide ndi siliva ku ores ndi njira yovuta komanso yofunika kwambiri pamakampani amigodi. Cyanidation yakhala njira yayikulu kwambiri pazifukwa izi. Komabe, kuyesayesa kosalekeza kukuchitika pofuna kukhathamiritsa ndondomekoyi kuti zitsulo zamtengo wapatali ziwonjezeke komanso kuti ziwonjezeke bwino. Njira imodzi yotere yomwe yawonetsa lonjezo ndikugwiritsa ntchito ammonia mu njira ya oxygen yochuluka ya cyanidation. Nkhaniyi ikufotokoza momwe ammonia angathandizire kwambiri pakukweza mitengo ya golide ndi siliva.

Zoyambira za Cyanidation

Cyanidation imachokera pa mfundo yakuti njira zofooka za sodium kapena potaziyamu cyanide kukhala ndi makonda osungunuka pa tinthu tating'ono ta golide ndi siliva kuposa zida zina zomwe zimapezeka mu golide. Pochita izi, malo atsopano a golidi akakhala ndi cyanide mu njira yamadzi yokhala ndi okosijeni waulere, zimachitika kuti amapanga golide wa cyanide pamodzi ndi hydroxide.

Ndondomekoyi imafuna kulamulira mosamala zinthu zingapo. Mwachitsanzo, mphamvu ya cyanide solution ndiyofunika kwambiri. Nthawi zambiri, njira yothetsera mphamvu yokwana paundi imodzi ya cyanide (KCN yofanana) ndi tani imodzi ya madzi (madzi) imagwiritsidwa ntchito, chifukwa izi zapezeka kuti ndi zamphamvu mokwanira pamabwalo ambiri owongoka a cyanide. Ntchito yoyesera yawonetsa kuti mphamvu iyi imapereka mphamvu yotha kusungunuka. Kuphatikiza apo, yankho lofooka silimakhudzidwa kwambiri ndi ma cyanicides (minerals omwe amatha kukhala ndi zotsatirapo zoyipa pamachitidwe a cyanidation), komanso kuopsa kwapoyizoni wautsi wopangidwa ndi nthunzi nyengo yotentha kumachepetsedwa.

Kutentha kumathandizanso kwambiri. M'madera ozizira, mayankho amatenthedwa mpaka pafupifupi 70 ° F kuti asungunuke bwino. Pamwamba pa kutenthaku, kutayika kwa cyanide mwa kuwonongeka kumakhala nkhawa yaikulu. Mwachidziwitso, golide amasungunuka mofulumira kwambiri mu yankho pa kutentha kwa 138 ° F.

Udindo wa Ammonia mu Oxygen - Rich Cyanidation Process

Kuvuta ndi Metal Ions

Ammonia amatha kupanga zinthu zovuta ndi ma ion achitsulo osiyanasiyana omwe amapezeka mu ore. Pankhani yochotsa golidi ndi siliva, imatha kuyanjana ndi ayoni amkuwa, omwe amapezeka m'miyala yambiri yagolide. Mkuwa umatha kudya cyanide ndikusokoneza kutulutsa golide ndi siliva. Mwa kupanga copper - ammonia complexes, ammonia amachepetsa mpikisano wa cyanide ions, kupanga cyanide yochuluka kuti iwonongeke golide ndi siliva. Zotsatira zake, kukhalapo kwa ammonia kumathandizira kukhalabe ndi ayoni aulere a cyanide mu yankho, lomwe limapindulitsa pakutulutsa golide ndi siliva.

Chikoka pa Electrochemical Environment

Ammonia imatha kusinthanso chilengedwe cha electrochemical ya leaching system. Zitha kukhudza kuthekera kwa redox yankho, lomwe limakhudzanso makutidwe ndi okosijeni ndi kusungunuka kwa golide ndi siliva. M'malo okhala ndi okosijeni, kupezeka kwa ammonia kumatha kupangitsa kuti mamolekyu okosijeni ayambike. Kupititsa patsogolo kwa okosijeni kumeneku kumalimbikitsa kutulutsa kwa golide ndi siliva kumagulu awo a cyanide. Mwachitsanzo, pankhani ya golidi, njira yochitira zinthu imatha kusinthidwa m'njira yomwe imathandizira kupanga golide wa cyanide mogwira mtima.

Kukweza kwa Mineral Surface Properties

Ammonia amatha kuyanjana ndi pamwamba pa mchere womwe uli mu ore. Mchere wina womwe ndi wovuta kutsika mwachindunji ukhoza kusinthidwa ndi ammonia pamwamba pake. Kusintha kumeneku kungapangitse kuti pamwamba pakhale ma ion a cyanide, motero kumapangitsa kuti leaching ikhale yabwino. Mwachitsanzo, mchere wina wokhala ndi siliva ukhoza kukhala ndi zokutira pamwamba zomwe zimalepheretsa ma ion cyanide. Ammonia amatha kuchitapo kanthu ndi zokutira izi kapena adsorb pamtunda wa mchere, kusintha kuchuluka kwake komanso kusinthika kwamankhwala, ndikulola kuti ayoni a cyanide achite bwino ndi siliva mkati mwa mchere.

Maphunziro a Nkhani ndi Magwiritsidwe Othandiza

Mu ntchito zothandiza pa golidi - siliva mgodi, ntchito mbali - akupera - pamene - leaching ndi mpweya - wolemera cyanidation ndondomeko anali pamodzi ndi Kuwonjezera ammonia. Pokhapokha kuti njira yopangira yoyambirira sinasinthe, kuwonjezera kuchuluka kwa ammonia mu gawo loyamba - kugaya kunachitika. Zotsatira zake zinali zodabwitsa. Poyerekeza ndi zinthu popanda kuwonjezera ammonia, golide cyanidation leaching mlingo wawonjezeka ndi 0.47%, siliva leaching mlingo wawonjezeka ndi 5.33%, ndi mkuwa leaching mlingo unatsika ndi 6.50%. Izi sizinangowonjezera kuchira kwa zitsulo zamtengo wapatali komanso zidachepetsanso kusungunuka kwa mkuwa, womwe nthawi zambiri umakhala wosafunika - chifukwa mkuwa umatha kudya cyanide ndikusokoneza njira zobwezeretsa zitsulo.

Mu kafukufuku wina pa mtundu wina wa golide - ore siliva, kuwonjezera kwa ammonia mu mpweya - wolemera cyanidation ndondomeko inachititsa kwambiri kusintha kinetics leaching. Nthawi yofunikira kuti ifike pamlingo wapamwamba wa golidi ndi siliva leaching idachepetsedwa. Izi sizinangowonjezera kupititsa patsogolo kwa ndondomeko ya leaching komanso kupulumutsa mphamvu ndi chuma m'kupita kwanthawi.

Kukhathamiritsa ndi Kuganizira

Ngakhale ammonia amawonetsa kuthekera kwakukulu pakukweza mitengo ya golide ndi siliva munjira ya okosijeni - wolemera wa cyanidation, pali zinthu zingapo zomwe ziyenera kukonzedwa. Kuchulukitsa kwa ammonia ndikofunikira. Ammonia wochepa kwambiri sangakhale ndi chiwopsezo chachikulu pazovuta, chilengedwe cha electrochemical, kapena kusintha kwa mineral surface. Kumbali inayi, kuchuluka kwa ammonia kumatha kubweretsa kuchulukitsitsa kwamitengo, zovuta zachilengedwe zomwe zingachitike, ndipo zitha kusokoneza kuchuluka kwamankhwala amtundu wa leaching system.

Phindu la pH la yankho la leaching liyeneranso kuyang'aniridwa mosamala. Ammonia ndi maziko ofooka, ndipo kuwonjezera kwake kungakhudze pH ya yankho. Popeza njira ya cyanidation imakhudzidwa ndi pH, kukhalabe ndi pH yoyenera (nthawi zambiri kuzungulira 10 - 11) ndikofunikira kuti ma cyanide ion agwire bwino ntchito komanso momwe ma kinetics amachitira.

Komanso, ngakhale ammonia ndi reagents ena ntchito ndondomeko, monga laimu (omwe nthawi zambiri anawonjezera kusintha pH ndi kuteteza mapangidwe hydrogen cyanide mpweya), ayenera kuganizira. Kuwonetsetsa kuti zochita zonse za mankhwala mu leaching system zimagwira ntchito mogwirizana ndikofunikira kuti pakhale kuchuluka kwa golide ndi siliva.

Kutsiliza

Kugwiritsiridwa ntchito kwa ammonia mu njira ya okosijeni - yochuluka ya cyanidation imapereka njira yotheka komanso yothandiza yopititsira patsogolo mitengo ya golide ndi siliva. Kupyolera mu kusakaniza ndi ayoni zitsulo, kusinthidwa kwa chilengedwe cha electrochemical, ndi kusintha kwa mineral surface properties, ammonia amatha kusintha kwambiri kutulutsa kwachitsulo chamtengo wapatali. Komabe, kukhathamiritsa mosamalitsa magawo monga ndende ya ammonia, kuwongolera pH, komanso kuyanjana ndi ma reagents ena ndikofunikira kuti muzindikire bwino phindu la njirayi. Pamene makampani a migodi akupitiriza kufunafuna njira zowonjezereka komanso zokhazikika zopezera zitsulo zamtengo wapatali, ntchito ya ammonia muzochita za cyanidation ikuyenera kulandira chidwi kwambiri ndi kufufuza kwina.