Fahimtar rawar sodium cyanide a cikin aikin leken asirin gwal

A cikin hadaddun duniya na Zinariya hakar ma'adinai, fitar da wannan ƙarfe mai daraja daga ma'adinan sa wani tsari ne da ke cike da madaidaicin kimiyya da fasahar kere-kere. Ɗayan sinadari da ya yi fice a cikin wannan tsari shine Sodium cyanide, wani fili wanda ya kasance mai mahimmanci ga masana'antar hakar gwal fiye da karni. Wannan labarin ya zurfafa cikin rawar da sodium Cyanide a cikin hakar gwal, musamman a cikin aikin leaching, bincika halayen sinadarai, aikace-aikacensa, da matakan da aka ɗauka don tabbatar da aminci da dorewar amfani.

Sinadarin Reactivity na Sodium Cyanide tare da Zinariya

sodium cyanide (NaCN) fari ne, kauri mai kauri wanda yake narkewa sosai a cikin ruwa. A cikin mahallin hakar zinare, mafi mahimmancin dukiyarsa shine ikon amsawa da zinare a gaban iskar oxygen don samar da hadadden gwal mai narkewa. Wannan dauki shine tushen Tsarin Cyanidation, wanda ita ce hanya mafi rinjaye don hakar zinare tun daga shekarun 1890.

Ma'auni na sinadarai don amsawa tsakanin zinariya, sodium cyanide, oxygen, da ruwa sune kamar haka:

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

A cikin wannan halayen, zinari yana da oxidized kuma yana samar da hadaddun tare da ions cyanide. Oxygen yana aiki a matsayin wakili na oxidizing, yana sauƙaƙe narkar da zinariya. Sakamakon hadaddun, sodium aurocyanide (Na[Au(CN)₂]), yana narkewa cikin ruwa, yana barin gwal ɗin ya rabu da matrix na tama.

Babban solubility na sodium cyanide a cikin ruwa yana da mahimmanci don tasiri a cikin tsarin leaching. Yana ba da damar saurin yaɗuwar ion cyanide ta cikin ma'adinai, yana haɓaka lamba tsakanin reagent da barbashi na gwal. Wannan, bi da bi, yana haɓaka ƙimar amsawa kuma yana haɓaka haɓakar haɓakar zinare gaba ɗaya.

Aikace-aikace a cikin Tsarukan Leaching na Zinare daban-daban

Heap Leaching

Leaching heap wata hanya ce da ake amfani da ita sosai don sarrafa ma'adinan zinare marasa daraja. A cikin wannan tsari, ana murƙushe ma'adinan kuma an jera shi cikin manyan tudu a kan layin da ba zai iya jurewa ba. Maganin dilute sodium cyanide, yawanci a cikin kewayon 0.01% zuwa 0.05%, ana fesa shi akan tulin. Maganin cyanide ya ratsa ta cikin ma'adinan, yana amsawa tare da zinariya kuma ya narkar da shi. Maganin ciki, wanda ke dauke da narkar da zinari, ana tattara shi a kasan tudun kuma a kara sarrafa shi don dawo da gwal.

Leaching heap hanya ce mai tsada don magance manyan juzu'in tama mai ƙarancin ƙima. Yin amfani da sodium cyanide a cikin wannan tsari yana ba da damar fitar da zinari daga ma'adanai waɗanda ba za a iya sarrafa su ba. Koyaya, yana buƙatar kulawa da hankali don hana gurɓataccen muhalli, saboda maganin cyanide na iya yuwuwa shiga cikin ƙasa da ruwa da ke kewaye idan ba a ƙunshe da kyau ba.

Carbon-in-Leach (CIL) da Tsarin Carbon-in-Pulp (CIP).

Ana amfani da hanyoyin CIL da CIP don sarrafa ma'aunin zinare mafi girma ko ma'aunin gwal. A cikin waɗannan matakai, ma'adinan yana fara ƙasa sannan kuma a haɗe shi da maganin sodium cyanide a cikin jerin tankuna masu tayar da hankali. Zinariya ta narke a cikin maganin cyanide, yana samar da hadadden gwal mai narkewa.

A cikin tsarin CIL, ana ƙara carbon da aka kunna kai tsaye zuwa tankunan leach. The carbon adsorbs hadaddun zinariya, yadda ya kamata raba zinariya daga bayani. Ana cire carbon ɗin da aka ɗora daga cikin tankunan kuma a ƙara sarrafa shi don dawo da gwal. A cikin tsarin CIP, an fara raba slurry na leached daga maganin, sa'an nan kuma an wuce maganin ta cikin jerin ginshiƙan carbon, inda aka sanya zinare a kan carbon.

Duk hanyoyin CIL da CIP suna ba da ƙimar dawo da gwal mai girma kuma suna da inganci dangane da amfani da reagent. Yin amfani da sodium cyanide a cikin waɗannan matakai yana ba da damar zaɓin narkar da zinariya, rage yawan hakar wasu karafa da ke cikin ma'adinai.

Abubuwan Da Ke Taimakawa Ingantacciyar Sodium Cyanide a Leaching

Ingancin sodium cyanide a cikin Zinariya leaching Abubuwa da yawa sun rinjayi tsarin:

1. Halayen Ore: Nau'i da abun da ke ciki na ma'adinai suna taka muhimmiyar rawa wajen aikin leaching. Ores tare da babban abun ciki na zinari da ingantaccen ma'adinai, irin su waɗanda ke da ƙarancin abun ciki na sulfide, suna haifar da ƙimar dawo da zinariya mafi girma. Bugu da ƙari, girman barbashi na tama yana rinjayar wurin da ake samu don amsawa. Ƙwaƙwalwar ƙasa mai kyau gabaɗaya tana haifar da ingantaccen leaching.

2. Cyanide Concentration: Matsayin sodium cyanide a cikin maganin leaching shine ma'auni mai mahimmanci. Babban taro na cyanide zai iya ƙara yawan rushewar gwal, amma kuma yana ƙara farashin reagent da yuwuwar haɗarin muhalli. Ƙaddamar da ƙaddamarwar cyanide yana da mahimmanci don daidaita daidaitattun hakar zinare da la'akari da tattalin arziki da muhalli.

3. Samun Oxygen: Kamar yadda ake buƙatar iskar oxygen don oxidation na zinariya, samuwarta a cikin tsarin leaching yana da mahimmanci. isassun iskar iska ko ƙara abubuwan da ke haifar da iskar oxygen na iya haɓaka aikin leaching. A wasu lokuta, ana iya amfani da madadin oxidants kamar hydrogen peroxide ko ozone don inganta haɓakar halayen.

4. pH na Magani: pH na maganin leaching yana rinjayar kwanciyar hankali na ions cyanide da solubility na hadaddun zinariya. Dan kadan alkaline pH, yawanci a cikin kewayon 10 zuwa 11. shine mafi kyau ga tsarin cyanidation. Daidaita pH zai iya taimakawa hana hydrolysis na cyanide kuma tabbatar da ingantaccen rushewar gwal.

La'akarin Muhalli da Tsaro

Sodium cyanide abu ne mai guba sosai, kuma amfani da shi wajen hakar gwal yana buƙatar tsauraran matakan muhalli da aminci don kasancewa:

Tasirin Muhalli

Babban damuwa na muhalli da ke hade da amfani da sodium cyanide a cikin hakar zinari shine yuwuwar sakin cyanide a cikin yanayi. Cyanide zai iya zama mai guba ga rayuwar ruwa, tsirrai, da dabbobi idan ya shiga cikin ruwa ko ƙasa. Don rage wannan haɗari, ayyukan hakar ma'adinai suna amfani da nau'o'in tsarin kula da muhalli, ciki har da yin amfani da madatsun ruwan wutsiya masu layi don ƙunsar mafita mai ɗaukar cyanide, maganin zubar da ruwa don rage matakan cyanide, da aiwatar da shirye-shiryen sa ido don gano duk wani abu mai yuwuwa ko zubar da ruwa.

Matakan Tsaro ga Ma'aikata

Ma'aikatan da ke aikin hakar gwal, musamman masu sarrafa sodium cyanide, suna cikin haɗarin kamuwa da wannan sinadari mai guba. Don tabbatar da amincin su, kamfanonin hakar ma'adinai suna aiwatar da tsauraran ka'idojin aminci. Waɗannan sun haɗa da ba wa ma’aikata kayan kariya na sirri, kamar safar hannu, tabarau, da na’urar numfashi, da horar da su kan yadda ya dace da sarrafa sinadarin sodium cyanide. Bugu da ƙari, ana yin tsarin tsaro don hana zubewar haɗari da kuma ba da amsa da sauri a cikin lamarin gaggawa.

Tsarin tsari

Amfani da sodium cyanide a cikin hakar gwal yana ƙarƙashin tsauraran tsarin kulawa a yawancin ƙasashe. Dokoki suna kula da samarwa, sufuri, adanawa, da amfani da sodium cyanide, da kuma sarrafa sharar da ke kunshe da cyanide. Ana buƙatar kamfanonin hakar ma'adinai su bi waɗannan ka'idoji don tabbatar da aminci da dorewar aiki na ma'adinan su.

Madadin Sodium Cyanide

A cikin 'yan shekarun nan, an sami karuwar sha'awar haɓaka wasu hanyoyin da za a bi don hakar zinare waɗanda ba su dogara ga amfani da sodium cyanide ba. Wasu hanyoyin da za a iya bi sun haɗa da:

Thiosulfate Leaching

Leaching Thiosulfate tsari ne da ke amfani da ion thiosulfate, kamar sodium thiosulfate, don narkar da gwal. Wannan hanya tana ba da fa'idodi da yawa akan cyanidation, gami da ƙarancin guba, saurin leaching rates, da ikon sarrafa ma'adinai waɗanda ke da wahalar bi da cyanide. Koyaya, leaching na thiosulfate shima yana da ƙalubalensa, kamar buƙatar kulawa da hankali game da yanayin leaching da ƙarin farashi na reagent.

Bioleaching

Bioleaching wani tsari ne na nazarin halittu wanda ke amfani da ƙananan ƙwayoyin cuta don cire zinariya daga tama. Wannan hanyar tana da alaƙa da muhalli kuma ana iya amfani da ita don magance ƙarancin ƙima. Koyaya, bioleaching tsari ne mai ɗan jinkiri, kuma aikace-aikacen sa a halin yanzu yana iyakance ga wasu nau'ikan ma'adinai.

Sauran Fasaha masu tasowa

Har ila yau, akwai wasu fasahohin da suka kunno kai, kamar yin amfani da ruwa na ionic da ruwa mai mahimmanci, waɗanda ke nuna alƙawarin fitar da gwal. Waɗannan fasahohin har yanzu suna cikin matakin gwaji, amma suna da yuwuwar bayar da ingantattun hanyoyin da za su dace da muhalli ga hanyoyin cyanidation na gargajiya.

Kammalawa

Sodium cyanide ya taka muhimmiyar rawa a masana'antar hakar gwal fiye da karni, wanda ke ba da damar hako zinari mai inganci daga ma'adanin sa. Ƙarfinsa na samar da gidaje masu narkewa tare da zinariya a gaban iskar oxygen ya sa ya zama mai tasiri sosai a cikin tsarin leaching. Duk da haka, yin amfani da sodium cyanide kuma yana zuwa tare da ƙalubalen muhalli da aminci, wanda ya haifar da ci gaba da tsauraran ka'idoji da kuma neman hanyoyin da za a iya cire zinariya.

Yayin da masana'antar hakar gwal ke ci gaba da haɓakawa, da alama za mu ga ƙarin fifiko kan haɓakawa da ɗaukar sabbin fasahohi masu dorewa da muhalli. Duk da haka, don nan gaba mai yiwuwa, sodium cyanide zai iya kasancewa wani muhimmin sashi na tsarin hakar zinare, duk da cewa tare da ƙarin bincike da aiwatar da ingantattun matakan muhalli da aminci.