Tsarin Leaching na Cyanide a cikin Haƙar ma'adinan Zinare: Cikakkun tsari daga Rushewa zuwa farfadowa

Gabatarwa

Hako zinare daga ma'adanai ya kasance abin sha'awa sosai tsawon ƙarni. Daga cikin hanyoyi daban-daban da ake da su, haƙo Cyanide ya fito a matsayin ɗaya daga cikin dabarun da aka fi amfani da su a masana'antar haƙo zinare ta kasuwanci . Wannan tsari yana ba da damar wargaza zinare cikin inganci daga kayan da ake amfani da su, wanda hakan zai ba da damar dawo da ƙarfe mai daraja cikin tsari mai ƙarfi. Wannan labarin zai zurfafa cikin cikakken tsarin haƙo cyanide a cikin haƙo zinare, tun daga farkon wargaza zinare a cikin maganin cyanide zuwa ƙarshe wargaza ƙarfe.

Rushewar Zinariya a cikin Maganin Cyanide

Maganganun Sinadarai Sun Shiga

Rushewar zinari a cikin maganin cyanide ya dogara ne akan rikitattun halayen halayen sinadarai. Za a iya wakilta ra'ayin gaba ɗaya ta hanyar ma'auni mai zuwa:

4Au + 8NaCN + O₂ + 2H₂O → 4Na[Au(CN)₂] + 4NaOH

A cikin wannan amsawar, zinare (Au) yana amsawa da Sodium cyanide (NaCN) a gaban iskar oxygen (O₂) da ruwa (H₂O) don samar da sodium dicyanoaurate (Na[Au(CN)₂]) da sodium hydroxide (NaOH). Matsayin iskar oxygen a cikin wannan amsawar yana da mahimmanci domin yana aiki a matsayin mai samar da iskar oxygen, yana sauƙaƙa narkewar zinare.

Sharuɗɗa don Mafi kyawun Rushewa

Don ingantaccen narkar da gwal, yanayi da yawa na buƙatar kulawa da hankali. Ƙaddamar da cyanide a cikin maganin shine mahimmancin mahimmanci. Yawanci, ana amfani da taro na 0.05 - 0.1% NaCN a cikin aikin leaching. Matsakaicin mafi girma zai iya haifar da ƙara yawan amfani da cyanide ba tare da karuwa mai yawa a cikin narkar da zinariya ba, yayin da ƙananan ƙaddamarwa zai iya haifar da jinkirin jinkirin da rashin cikawa.

Hakanan pH na maganin yana taka muhimmiyar rawa. Tsarin leaching ya fi tasiri a cikin matsakaicin matsakaici na alkaline, tare da kewayon pH na 9.5 - 11. A wannan pH, ions cyanide suna cikin nau'in da ba a raba su ba (HCN), wanda ya fi mayar da hankali ga zinariya. Ana samun daidaita pH ta hanyar ƙara lemun tsami (CaO) zuwa maganin leaching.

Zazzabi wani muhimmin ma'auni ne. Ko da yake amsawar na iya faruwa a yanayin zafi, ɗan ƙaramin zafin jiki na kusan 25 - 35 ° C na iya haɓaka ƙimar narkar da gwal. Duk da haka, ƙara yawan zafin jiki zai iya haifar da lalacewa na cyanide, rage tasirinsa.

Pre-maganin Ores

Murkushewa da Nika

Kafin a fara aikin cire sinadarin cyanide daga ƙasa, ana buƙatar a yi wa ma'adinan da ke ɗauke da zinare magani. Mataki na farko a wannan aikin kafin a fara shi ne a murƙushe su da niƙa su . Ana niƙa ma'adinan don rage girmansu sannan a niƙa su zuwa ƙananan ƙwayoyin cuta. Wannan yana ƙara girman saman ma'adinan, wanda ke ba da damar yin hulɗa mai inganci tsakanin ƙwayoyin zinare da maganin cyanide yayin aikin cire sinadarin.

Ana sarrafa matakin niƙa a hankali. Nika fiye da kima na iya haifar da samuwar slimes masu kyau, wanda zai iya haifar da matsala yayin matakan rabuwa mai ƙarfi na gaba. A gefe guda, niƙawar ƙasa na iya haifar da rashin isassun filaye na barbashi na gwal, wanda zai haifar da rashin cikawa.

Roasting da Bio-oxidation

A wasu lokuta, ma'adinan gwal na iya ƙunsar ma'adinan da ba su da ƙarfi waɗanda ke hana rushewar zinariya ta hanyar cyanide kai tsaye. Don irin wannan ma'adinai, ana iya buƙatar ƙarin hanyoyin magani kafin magani kamar gasasshen ko bio-oxidation.

Gasasshen ya ƙunshi dumama ma'adinan a gaban iska don oxidize da ma'adanai masu jujjuyawa, kamar sulfides. Wannan tsari na oxidation yana rushe ma'adanai, yana sakin gwal ɗin gwal kuma yana sa su zama mafi sauƙi ga maganin cyanide.

Bio-oxidation, a daya bangaren, yana amfani da microorganisms don oxidize da refractory ma'adanai. Wannan madadin gasasshen muhalli ne da ya fi dacewa da muhalli yayin da yake aiki a ƙananan yanayin zafi kuma yana haifar da ƙarancin hayaki mai cutarwa. An zaɓi ƙananan ƙwayoyin cuta, yawanci ƙwayoyin cuta ko fungi, bisa ga ikon su na yin oxidize takamaiman ma'adinan da ke cikin ma'adinai.

Tsarin Leaching

Rushewar Tankin Leaching

Leaching na tanki yana daya daga cikin hanyoyin da aka saba amfani da shi don leaching cyanide. A cikin wannan tsari, an haɗa tama da aka riga aka yi da ita tare da maganin cyanide a cikin manyan tankuna masu motsawa. Tankuna suna sanye take da masu tayar da hankali waɗanda ke tabbatar da haɗakar tama da mafita sosai, suna haɓaka hulɗar tsakanin gwanayen gwal da ion cyanide.

Lokacin leaching na iya bambanta dangane da yanayin ma'adinai da yanayin aiki. Gabaɗaya, tsarin leaching na iya ɗaukar ko'ina daga sa'o'i da yawa zuwa kwanaki da yawa. A wannan lokacin, ana ɗaukar samfuran leach ɗin lokaci-lokaci kuma ana bincika su don lura da ci gaban narkar da gwal.

Heap Leaching

Leaching leaching wata hanya ce da ake amfani da ita sosai, musamman ga ma'adinan zinare marasa daraja. A cikin wannan tsari, ana tattara ma'adinan da aka niƙa a cikin manyan tudu a kan layin da ba zai iya jurewa ba. Ana fesa maganin cyanide a saman tudun a bar shi ya ratsa ta cikin takin. Yayin da maganin ya ratsa cikin tudun, yana narkar da barbashi na gwal, kuma ana tattara maganin ciki da aka samu a kasan tsibin.

Tarin tsiya hanya ce mafi araha idan aka kwatanta da takin da aka yi da Stirred domin yana buƙatar ƙarancin jari a kayan aiki. Duk da haka, tsari ne mai jinkiri kuma ya fi dacewa da ma'adanai masu ƙarancin adadin zinare.

Rabuwar Ruwa Mai ƙarfi

tacewa

Bayan an gama aikin leaching, mataki na gaba shine raba ragowar datti ( wutsiya) daga maganin ciki, wanda ya ƙunshi narkar da gwal. Tace yana daya daga cikin hanyoyin da aka fi amfani da su don rabuwa da ruwa mai kauri. A cikin wannan tsari, slurry (cakuda mai ƙarfi da ruwa) ana wucewa ta hanyar matattarar tacewa, kamar zane mai tacewa ko matsi mai tacewa. Ana riƙe da ƙaƙƙarfan ɓangarorin akan matsakaicin tacewa, yayin da ruwa (maganin ciki) ya wuce kuma ana tattara shi.

Zaɓin matsakaicin tacewa ya dogara da yanayin ƙaƙƙarfan barbashi da yanayin aiki. Misali, a cikin yanayin da ƙaƙƙarfan ɓangarorin sun yi kyau sosai, ana iya buƙatar kyalle mai laushi mai kyau.

Bacin rai

Decantation wata hanya ce da za a iya amfani da ita don rarrabuwar ruwa mai ƙarfi, musamman lokacin da ƙaƙƙarfan barbashi suna da girma da sauƙi. A cikin wannan tsari, ana barin slurry ya tsaya a cikin tanki na wani lokaci. Daskararrun barbashi suna sauka zuwa kasan tanki saboda nauyi, sannan a cire tsaftataccen ruwa (maganin ciki) a hankali.

Decantation hanya ce mai sauƙi kuma mafi ƙarancin ƙarfi - hanya mai ƙarfi idan aka kwatanta da tacewa. Duk da haka, maiyuwa ba zai yi tasiri sosai ba a cikin rarrabuwar ƙaƙƙarfan ƙaƙƙarfan barbashi.

Farfadowar Zinariya daga Maganin Ciki

Kunnawa Carbon Adsorption

Ɗaya daga cikin hanyoyin da aka fi amfani da su wajen dawo da zinare daga maganin da ke cikin ciki shine activated carbon adsorption . A cikin wannan tsari, ana ƙara activated carbon a cikin maganin da ke cikin ciki. Haɗin zinare - cyanide yana da ƙarfi sosai ga saman carbon da aka kunna, kuma sakamakon haka, zinare yana shaƙa a kan ƙwayoyin carbon.

Ana raba barbashi na carbon daga maganin, yawanci ta hanyar nunawa ko tacewa. Kabon da aka ɗora wa zinari ana ƙara sarrafa shi don lalata gwal ɗin. Ana yin wannan yawanci ta hanyar ƙaddamar da carbon zuwa babban maganin tururi mai zafi ko ta amfani da wakili na lalata sinadarai.

Zinc Hazo

Zinc hazo, kuma aka sani da tsarin Merrill - Crowe, wata hanya ce don dawo da gwal. A cikin wannan tsari, ana ƙara ƙurar zinc zuwa maganin ciki. Zinc ya fi ƙarfin lantarki fiye da zinariya, kuma a sakamakon haka, yana kawar da zinariya daga zinariya - cyanide complex. Ana iya wakilta martanin da ma'auni mai zuwa:

2Na[Au(CN)₂] + Zn → 2Au + Na₂[Zn(CN)₄]

Zinare da aka haɗe, tare da kowane zinc da ba a yi ba, yana samar da sludge mai ƙarfi. Ana raba wannan sludge daga maganin, kuma an ƙara tace zinare don samun samfur mai tsabta.

Tace Zinariya

Murmushi

Da zarar an samo zinare daga maganin ciki, yawanci yana buƙatar a tace shi don cire duk sauran ƙazanta. Yin narkewa yana ɗaya daga cikin hanyoyin da aka fi sani don tace zinare. A cikin wannan tsari, kayan da ke dauke da zinari suna mai zafi zuwa babban zafin jiki a gaban motsi, irin su borax. Juyin yana taimakawa wajen rage wurin narkar da gwal ɗin kuma yana mai da martani tare da ƙazanta, yana samar da shingen da za a iya raba shi da narkakken gwal.

Ana zuba zinariyar da aka narkar da ita a cikin gyare-gyare don samar da ingots. Ana iya ƙara sarrafa waɗannan ingots ko sayar da su azaman samfurin da ya ƙare.

Electrolytic Refining

Electrolytic tace hanya ce ta ci gaba don tace zinare. A cikin wannan tsari, an sanya zinari - mai ɗauke da anode a cikin tantanin halitta na electrolytic tare da cathode na zinariya mai tsabta. Electrolyte yawanci bayani ne na chloride na gwal ko wasu gishirin zinariya. Lokacin da wutar lantarki ta wuce ta cikin tantanin halitta, zinare daga anode ya narke a cikin electrolyte sannan ya ajiye a kan cathode.

Abubuwan da suka fi ƙarfin lantarki fiye da zinariya suna narkewa a cikin electrolyte amma ba sa ajiya a kan cathode, yayin da ƙazantattun da ba su da ƙarfin lantarki fiye da zinariya sun kasance a matsayin sludge a kasan tantanin halitta. Wannan yana haifar da babban samfurin zinariya mai tsabta.

La'akari da Muhalli

Gudanar da Cyanide

Cyanide abu ne mai guba sosai, kuma ingantaccen sarrafa cyanide a cikin aikin hakar gwal yana da matuƙar mahimmanci. Amfani da cyanide a cikin hakar gwal yana da ƙayyadaddun ƙayyadaddun tsari a ƙasashe da yawa don rage tasirinsa ga muhalli da lafiyar ɗan adam.

Ɗaya daga cikin mahimman abubuwan sarrafa cyanide shine rigakafin zubar da cyanide. Ana buƙatar ayyukan hakar ma'adinai don samun ingantaccen tsarin tsare-tsare don hana cyanide - mai ɗauke da mafita daga zubewa cikin yanayi. Bugu da ƙari, maganin cyanide - wanda ke dauke da ruwan sha yana da mahimmanci. Akwai hanyoyi da yawa da ake da su don magance cyanide - mai ɗauke da ruwa mai datti, irin su oxidation na sinadarai, jiyya na halitta, da musayar ion.

Zubar da wutsiya

Daskararrun ragowar ( wutsiya) da aka samar bayan aikin dawo da gwal shima yana buƙatar a zubar da shi yadda ya kamata. Wutsiyar wutsiya na iya ƙunsar adadin cyanide da sauran ƙarfe masu nauyi, waɗanda za su iya haifar da barazana ga muhalli idan ba a sarrafa su daidai ba.

Hanya ɗaya ta gama gari don zubar da wutsiya ita ce adana su a madatsun wutsiya. An tsara waɗannan madatsun ruwa don ɗaukar wutsiya da kuma hana fitar da gurɓataccen abu a cikin muhalli. A wasu lokuta, ana iya sake sarrafa wutsiya don dawo da duk wasu ma'adanai masu mahimmanci ko don rage tasirin muhalli.

Kammalawa

Tsarin leaching na cyanide a cikin hakar gwal wani tsari ne mai rikitarwa kuma mai yawa-mataki wanda ya haɗa da narkar da zinare a cikin maganin cyanide, pre-maganin ores, leaching, m - rabuwar ruwa, dawo da gwal, tacewa, da sarrafa muhalli. Kowane mataki a cikin wannan tsari ana sarrafa shi a hankali don tabbatar da ingantaccen hakowa da dawo da gwal yayin da rage tasirin muhalli. Duk da ƙalubalen da ke tattare da amfani da cyanide, tsarin ya kasance hanya mai mahimmanci kuma ana amfani da ita sosai a cikin masana'antar hakar gwal na kasuwanci saboda yawan inganci da ƙananan farashi. Koyaya, ana ci gaba da gudanar da bincike da haɓakawa don haɓaka wasu hanyoyin da suka fi dacewa da muhalli da dorewa.