Inkqubo yeCyanide Gold Extraction yaManzi amdaka

Okwangoku, i i-cyanide indlela yokutsalwa kwegolide yenye yeenkqubo eziphambili zokunyibilikisa igolide eTshayina. Isebenzisa isisombululo se-cyanide ukukhupha igolide kwi-ores, enezinga eliphezulu lokubuyisela, ukuguquguquka okunamandla kwiipropati ze-ore, kunye nokukwazi ukuvelisa igolide kwindawo. Ukususela ekusetyenzisweni kokuqala kwesisombululo se-cyanide ukukhupha igolide kwi-ores ngo-1887. le ndlela isetyenziswe ngokubanzi kude kube ngoku. Nangona kunjalo, ukutsalwa kwegolide yecyanide kuvelisa inani elikhulu lezinto eziyityhefu neziyingozi, ezibeka isoyikiso esikhulu kwindawo engqongileyo nakubantu. Ngoko ke, ukuze kuncitshiswe umonakalo, kuyimfuneko ukufunda iindlela zonyango lwe-cyanide yegolide yokukhutshwa kwamanzi amdaka. Inani elikhulu labaphandi baye bashwankathela iindlela zonyango, imigaqo yeekhemikhali, kunye neendlela zophuhliso ze-cyanide - eziqulethe amanzi angcolileyo, kodwa uninzi lwazo luxoxa kuphela indlela enye okanye ezimbini. Ke ngoko, eli nqaku lenza uhlalutyo oluneenkcukacha lweendlela ezahlukeneyo zonyango lwe-cyanide yegolide yokutsalwa kwamanzi amdaka asetyenziswayo ngoku kwishishini, lithelekisa iingenelo, izinto ezingeloncedo, kunye neemeko zesicelo sendlela nganye, enokubaluleka okukhokelayo kwizicelo ezifanayo kwimveliso yokwenyani.

I. Imithombo kunye neeNgozi zeCyanide Gold Extraction Amanzi amdaka

Umgaqo ophambili wokutsalwa kwegolide yecyanide kukuba kwindawo ene-aerobic, sodium cyanide iphendula negolide ukuze yenze iicomplex zegolide, ezithi emva koko zinyibilike. Emva koko, igolide ingakhutshwa ngokuyikhulisa ngokusebenzisa i-activated ICarbon ukufunxwa okanye ukufuduswa yi-zinc powder evela kwi-gold cyanide. Kwangaxeshanye, ezinye izinyithi ezinzima ezifana nesilivere, ubhedu, kunye ne-zinc nazo zenza ii-complexes kwaye zinyibilike.

The iicyanides isetyenziswe kwi-reaction kunye ne-complexes eveliswayo yonke into eyityhefu kunye neyingozi. I-sodium cyanide ilula ukwenza i-hydrolyze kwaye i-Class 1 into enetyhefu kakhulu, enedosi ebulalayo ye-0.10g. Nini IiCyanides Ukuvuza emanzini, kuyingozi kakhulu kwizinto eziphilayo ezisemanzini, kwaye kuya kubangela isoyikiso esikhulu ebantwini nakwimeko engqongileyo. Ke ngoko, ukunyangwa kwamanzi amdaka e-cyanide gold extraction kubaluleke kakhulu.

II. IiNdlela eziPhambili zoNyango lweCyanide Gold Ukutsalwa kwamanzi amdaka

Indlela ye-Alkaline yeChlorination

Indlela yealkaline chlorination okwangoku yenye yezona ndlela zixhaphakileyo zokunyanga icyanide - equlathe amanzi amdaka aphuma kwicyanide gold extraction. Ikakhulu isebenzisa iklorini-esekelwe kwi-oxidants ukwenza i-cyanides kumanzi amdaka phantsi kweemeko zealkaline, iguqulelwe kwizinto ezingenayo ityhefu. Inkqubo yokuqhawula i-cyanide ye-alkaline chlorination yohlulwe ibe ngamanqanaba amabini:

Inqanaba lokuqala kukwenza i-cyanide ibe yicyanide, ebizwa ngokuba “yinqanaba le-oxidation elingaphelelanga”. I-CN⁻ isabela nge-OCl⁻ ukwenza i-CNCl kuqala, kwaye emva koko i-hydrolyzes ukuya kwi-CNO⁻. Kufuneka kuqatshelwe ukuba i-CNCl iguquguquka kakhulu kwaye inetyhefu phantsi kweemeko ze-acidic. Ngoko ke, ngexesha lokusebenza, ixabiso le-pH kufuneka lilawulwe ngokungqongqo ukuba libe kwi-alkaline state.

Inqanaba lesibini kukuqhubela phambili i-oxidize i-cyanate kwi-carbon dioxide kunye ne-nitrogen, ebizwa ngokuba yi-"complete oxidation stage". Ngexesha le-cyanide - inkqubo yokuqhawula, ixabiso le-pH linempembelelo enkulu kwi-oxidation reaction. Ixabiso le-pH yenqanaba lokuqala le-oxidation kufuneka ilawulwe kwi-10 - 11. kwaye ixesha lokuphendula liyi-10 - 15 imizuzu. Ixabiso le-pH yenqanaba lesibini le-oxidation kufuneka ilawulwe kwi-6.5 - 7.0. kwaye ixesha lokuphendula li-10 - 15 imizuzu.

Umgodi othile usebenzisa indlela ye-alkaline chlorination ukunyanga i-supernatant ye-cyanide slurry yomsila (ngomxholo we-cyanide we-200mg/L) kunye namanzi aphumayo asuka kwi-sedimentation tank (ngomxholo we-cyanide we-5mg / L). Ixabiso le-pH lilawulwa kwi-10 - 11. kunye ne-bleaching powder yongezwa kwinqanaba le-35 - 40 amaxesha omxholo we-cyanide wokuxuba kunye nokuvuselela. Emva kwe-sedimentation kwi-thickener, umxholo we-cyanide uwonke unokuncitshiswa ukuya kwi-0.1mg/L.

Indlela ye-alkaline chlorination yeyona ndlela ixhaphakileyo yokunyanga icyanide - equlathe amanzi amdaka, kwaye umgubo webleaching yeyona isetyenziswa kakhulu iklorine - based oxidant. Le ndlela ifanelekile ukunyanga i-cyanide gold extraction amanzi amdaka ngoxinzelelo oluphezulu okanye oluphantsi. Iyakwazi nokususa i-thiocyanate kunye ne-cyanide - equkethe ii-complexes (ngaphandle kwe-ferrocyanide complexes). I-medicament ifumaneka ngokubanzi, intsalela yenkunkuma eyenziweyo kulula ukuyicoca, kwaye umsebenzi ulula. Nangona kunjalo, indawo yokusebenza inzima xa usebenzisa umgubo webleach ukunyanga amanzi amdaka. Ngoku amanye amashishini asebenzisa ulwelo lwebleaching okanye ichlorine dioxide endaweni yoko, nto leyo ephucula indawo yokusebenza ukusa kumlinganiselo othile. Kodwa iigesi ezinetyhefu ziveliswa ngexesha lenkqubo yokusabela, kwaye inokonakala okukhulu kwizixhobo. Iindleko zonyango kunye neendleko zokulondolozwa ziphezulu kakhulu.

Indlela yokuHlanganisa iTyuwa yeFrerous

Indlela yokuxutywa kwetyuwa ye-ferrous yindlela yonyango yokukhutshwa kwamanzi amdaka e-cyanide ethe yavela kwiminyaka yakutshanje. Ngokulawula ukusabela kwexabiso le-pH kwi-7 - 8. ii-ion ze-ferrous zisabela nge-cyanide yasimahla kunye nezinye iikhompleksi zecyanide kumanzi amdaka e-cyanide egolide ukwenza imvula.

Iimvavanyo zibonise ukuba ngokubanzi, ukongeza kuphela i-ferrous sulfate ukunyanga amanzi amdaka e-cyanide yegolide ayinakwenza amanzi amdaka ahlangabezane nemigangatho yokukhupha. Ke ngoko, i-oxidant ngokubanzi kufuneka yongezwe kumanzi amdaka acociweyo ukuze kususwe ubunzulu be-cyanide. Ngethuba nje iimeko zilawulwa kakuhle, i-oxidant inokongezwa ngokuthe ngqo kunyango ngaphandle kokwahlula i-precipitate, kunye nomgangatho wokukhutshwa nawo unokufezekiswa. Oku kunokubaluleka okulungileyo xa kuthelekiswa nendlela yemveli yokwahlukana kuqala kwaye emva koko unyango.

Isinyibiliki esithile segolide sisebenzisa indlela yesodium sulfide - ferrous sulfate ukunyanga icyanide - ulwelo olungekho mgangathweni. Impembelelo inomxholo we-cyanide we-2500mg/L. Emva kokonyango, i-effluent inomxholo we-cyanide ongaphantsi kwe-20mg / L, kunye nesantya sokususwa kwe-99.2%, ebonisa iziphumo eziphawulekayo. Ubunzulu obulandelayo - unyango lusebenzisa i-sodium metabisulfite - indlela yomoya yokunciphisa i-cyanide iyonke ibe ngaphantsi kwe-0.4mg/L.

Indlela yokuxutywa kwetyuwa ye-ferrous yindlela yonyango esandula kuvela, ikakhulu esetyenziselwa ukunyanga i-cyanide ephezulu - equlethe amanzi amdaka. Inkqubo yayo ilula, i-investment yexesha elilodwa incinci, kulula ukuyisebenzisa, i-medicament (ingakumbi i-sulfate ye-ferrous) ifumaneka ngokubanzi, ayibizi, kwaye kulula ukuyisebenzisa. Nangona kunjalo, ngenxa yokuba isisombululo se-ferrous sulfate sineasidi, xa sixutywe namanzi amdaka e-cyanide yegolide, indawo yasekuhlaleni iba neasidi, kwaye kukho ithuba lokuvelisa igesi ye-hydrogen cyanide. Ngaphezu koko, ayikwazi ukususa i-thiocyanate, kwaye amanzi amdaka acociweyo asafuna unyango olunzulu ukuhlangabezana nemigangatho yokukhupha.

I-Sodium Metabisulfite - Indlela yoMoya

I-sodium metabisulfite - indlela yomoya iphuhliswa kwi-sulphur dioxide - indlela yomoya. Ngokukodwa isebenzisa impembelelo ye-synergistic ye-sodium metabisulfite kunye nomoya kwi-cyanides kumanzi amdaka ngaphakathi koluhlu oluthile lwe-pH, kunye nefuthe le-catalytic ye-ion zethusi, i-oxidize i-CN⁻ kwi-CNO⁻.

Ukuba umxholo we-cyanide kwi-cyanide - equlethe amanzi amdaka aphezulu, unyango lwangaphambili lunokwenziwa kuqala ukunciphisa ugxininiso olupheleleyo lwe-cyanide ukuya ngaphantsi kwe-100mg/L. Emva koko, i-metabisulfite ye-sodium kunye ne-sulfate yobhedu yongezwa, umoya owaneleyo uyaziswa, kwaye ixabiso le-pH lilawulwa (ngokuqhelekileyo lilawulwa kwi-7 - 8), ukuze i-cyanide ifakwe kwi-cyanate, ethi ke i-hydrolyzed ukwenza i-bicarbonate ion kunye ne-ammonia.

I-sodium metabisulfite-indlela yomoya ifanelekile ukunyanga amanzi amdaka e-cyanide yegolide ephantsi. Idosi yeyeza lincinci, amandla okusebenza aphantsi, kodwa utyalo-mali lwangaphambili lukhulu kakhulu, kwaye izixhobo ezinje ngee blowers kufuneka zongezwe. Iimfuno zezalathi zenkqubo zingqongqo, kwaye ukulawula ixabiso le-pH kubaluleke kakhulu. I-Copper sulfate nayo kufuneka yongezwe njenge-catalyst. Ixesha lokuphendula lide. Ukuba unyango alufanelekanga, inani elikhulu le-ammonium ions liya kuveliswa, kwaye i-slag eyenziweyo ayilula ukuyicoca. Kukho isixa esincinci segesi ye-ammonia eveliswe kwisiza, kwaye ayinasiphumo ekususeni i-thiocyanides.

Indlela ye-Hydrogen Peroxide

Indlela ye-hydrogen peroxide oxidation kukwenza i-cyanides ibe yi-CNO⁻ phantsi kobushushu obuqhelekileyo, i-alkaline (pH = 10 - 11) iimeko, kunye ne-Cu²⁺ njenge-catalyst, kwaye emva koko i-hydrolyzes ibe zizinto ezingenayo ityhefu. I-cyanides eyinkimbinkimbi (i-complexes ye-Cu, i-Zn, i-Pb, i-Ni, i-Cd) nayo iyahlukana ngenxa yokutshatyalaliswa kwe-cyanides kuzo. Iiyoni zeFerrocyanide kunye nezinye iiyoni zentsimbi enzima zenza iityuwa ezintsonkothileyo zeferrocyanide kwaye ziyasuswa. Ekugqibeleni, i-cyanide epheleleyo yoxinaniso kumanzi amdaka acociweyo inokuncitshiswa ibe ngaphantsi kwe-0.5mg/L.

Le ndlela ifanelekile ukunyanga i-cyanide ephantsi-equlethe amanzi amdaka. Isixhobo sonyango lwe-hydrogen peroxide silula kwaye kulula ukufikelela kulawulo oluzenzekelayo. Nangona kunjalo, i-cyanate eyenziwayo kufuneka ihlale ixesha elithile ukuze ibole ibe yi-CO₂ kunye ne-NH₃. Ukungalungi kukuba ukusebenzisa ubhedu njenge-catalyst kunokubangela ubhedu kumanzi akhutshiweyo ukuba lugqithise umgangatho, ixabiso lempahla eluhlaza liphezulu kakhulu, i-thiocyanides ayikwazi ukufakwa i-oxidized, kunye ne-ammonium ion zenziwa. Enyanisweni, amanzi amdaka asenayo ityhefu ethile. Ngaphezu koko, ekubeni i-hydrogen peroxide iyi-oxidant, inomhlwa omkhulu, kwaye kukho ubunzima kunye nobungozi bokuthuthwa kunye nokusetyenziswa.

Indlela ye-Acidification

Xa usebenzisa indlela ye-acidification ukunyanga i-cyanide - ulwelo olubi, indlela yokusabela kwayo inzima kakhulu, ngokukodwa iquka iinkqubo ezintathu: inkqubo ye-asidi ye-cyanide - equlethe amanzi amdaka, inkqubo yokuhluthwa kunye nokufunxa kwegesi yeHCN, kunye nenkqubo yokungathathi hlangothi kolwelo oluhlutshiweyo.

(1) I-Acidification reaction: I-cyanide - ulwelo olubi luhlanjululwa kwaye lucocwe ngeasidi. I-cyanides eyinkimbinkimbi kwi-liquid ehluphekileyo iya kwenza i-precipitates e-insoluble njenge-CuCN, i-CuSCN, kunye ne-Zn₂Fe (CN)₆ kwaye isuswe, kwaye ngexesha elifanayo, i-hydrogen cyanide yenziwe.

(2) Ukuguquguquka nokusabela kokufunxa: Ulwelo olungekho mgangathweni lufudunyezwa ngaphambili ukuya kutsho malunga ne-30℃ phambi kokwenziwa kweasidi. Kuba indawo yokubila ye-HCN iyi-26.5℃ kuphela, iyaguquguquka kakhulu. Ngoko ke, inqaba epakishweyo isetyenziswa njengobunzima - izixhobo zokudlulisa uqhagamshelwano phakathi kwegesi - ulwelo ezimbini - isigaba kwindlela ye-acidification, elula ukufezekisa ukuhluthwa kunye nokufunxa kwe-HCN.

(3) I-neutralization reaction: Ikalika okanye ialkali yolwelo isetyenziselwa ukwenza i-asidi ihluthwe. Iimolekyuli ze-HCN eziseleyo kwisisombululo ziya kuguqulwa zibe yifom ye-CN⁻. Indlela yokwenza iasidi ingachacha Isodium cyanide ukusuka kwicyanide - equlathe amanzi amdaka kwaye iqonde ukubuyiswa kobutyebi. Nangona kunjalo, ineemfuno eziphezulu zokutywinwa kwezixhobo, utyalo-mali lwangaphambili oluthe kratya, lufuna izakhono zokusebenza kwinqanaba eliphezulu, kwaye ukugcinwa kwezixhobo kunzima. Kukho neengozi ezithile zokhuseleko. Amanzi amdaka awenziwe emva kokubuyiselwa asafuna unyango olunzulu ukuhlangabezana nemigangatho yokukhupha.

Indlela ye-Electrolysis

Indlela ye-electrolysis isebenzisa i-electrochemical redox reactions ukutshabalalisa iicyanides kumanzi amdaka. Ngexesha le-ion electrolysis, i-cyanides ilahlekelwa yi-electron kwi-anode kwaye i-oxidized kwi-cyanate, i-carbonate, i-nitrogen, okanye i-ammonium. I-Cyanate iphinda ifakwe kwi-CO₂ kunye ne-H₂O. Iimpendulo eziphambili zezi:

CN⁻ + 2OH⁻ - 2e → CNO⁻ + H₂O (24)

2CN⁻ + 4OH⁻ - 6e → 2CO₂ + N₂ + 2H₂O (25)

Iimvavanyo ze-Electrolysis zisebenzisa i-ceramic eyenziwe ngokwayo - esekelwe kwi-lead dioxide electrode rod kunye ne-stainless-steel cathode plate ibonakalise ukuba ngokusebenzisa indlela ye-electrolysis yokuphatha i-cyanide - equlethe amanzi amdaka, emva kweeyure ze-2 ze-electrolysis, i-concentration ye-CN⁻ inokwehliswa ukusuka kwi-385mg / L ukuya kwi-58mg / L, kunye ne-Cu²/L ukusuka kwi-450mg ye-concentration ye-48mg / L. Ukongeza, i-Hunan Zhongnan Gold Smelter isebenzisa indlela ye-electrochemical ukunyanga amanzi amdaka e-cyanide yegolide, enokunciphisa i-cyanide iyonke ukusuka kwi-4g/L ukuya kwi-0.8g/L. Umahluko ukusuka ngasentla kukuba zombini i-anode kunye ne-cathode plate zenziwe ngamacwecwe ensimbi. Ngethuba lenkqubo yokusebenza, kungekhona nje kuphela amandla ombane asetyenzisiweyo, kodwa kunye neeplate zentsimbi ziyadliwa.

Indlela ye-electrolysis isetyenziswa ikakhulu ukunyanga i-cyanide ephezulu-equlethe amanzi amdaka. Isixhobo sithatha indawo encinci, inkqubo ilula kwaye kulula ukuyilawula, kodwa idla umthamo omkhulu wamandla ombane, kwaye iindleko zokusebenza ziphezulu kunendlela ye-alkaline chlorination. Izinga lokususa i-cyanide liyi-avareji, kwaye ayinayo impembelelo ekususeni i-cyanide complexes.

Okwangoku, phakathi kweendlela zonyango lwe-cyanide yegolide yokutsalwa kwamanzi amdaka, indlela ye-alkaline chlorination, indlela ye-asidi, kunye ne-sodium metabisulfite - indlela yomoya isetyenziswa ngokubanzi. Indlela ye-electrolysis kunye ne-ferrous salt complexation yeendlela ezisanda kuvela eziye zasetyenziswa ngempumelelo kunyango lwamashishini. Indlela yehydrogen peroxide oxidation ikakhulu yindlela yonyango olungxamisekileyo. Kukho ezinye iindlela ezininzi zonyango lokunyanga i-cyanide yegolide yokukhutshwa kwamanzi amdaka, njengendlela yokucoca yendalo, indlela yebhayoloji, indlela yokwahlula inwebu, i-ion - indlela yokutshintshiselana, njl.