Cov txheej txheem chlorination rau kho Cyanide Kub Sludge

Introduction

Hauv kev lag luam rho kub, cov av nplaum kub cyanide yog ib yam khoom uas tsim tawm thaum lub sijhawm ua cyanidation. Cov av nplaum no tsis yog tsuas muaj cov hlau muaj nqis xws li kub thiab nyiaj xwb tab sis kuj muaj cov tshuaj lom xws li cyanide . Kev kho cov av nplaum kub cyanide yog qhov tseem ceeb rau kev rov qab tau cov peev txheej thiab kev tiv thaiv ib puag ncig. Cov txheej txheem chlorination tau tshwm sim ua ib txoj hauv kev zoo rau kev kho cov av nplaum no, muab txoj hauv kev los cais cov hlau muaj nqis thiab tshem tawm cov tshuaj cyanide uas muaj.

Cov ntsiab cai ntawm chlorination txheej txheem

Oxidation thiab Selective Dissolution

Cov txheej txheem chlorination siv qhov zoo ntawm cov oxidation sib txawv - txo cov peev xwm ntawm cov hlau hauv ib qho chaw nruab nrab. Hauv cov ntsiab lus ntawm kev kho cov cyanide kub sludge, thaum ntxiv cov neeg sawv cev chlorinating (xws li sodium chlorate hauv ib qho chaw acidic), cov hlau uas muaj qis dua oxidation - txo cov peev xwm, xws li zinc, hlau, txhuas, thiab tooj liab, feem ntau yog oxidized thiab yaj hauv cov tshuaj. Piv txwv li, hauv ib qho chaw hydrochloric acid, cov hlau hauv cov kub sludge react nrog cov tshuaj. Tom qab ntawd, thaum ntxiv sodium chlorate, nws ua rau cov peev xwm ntawm cov tshuaj ntau ntxiv, tso cai rau tooj liab thiab lwm yam tsis huv uas tsis yaj hauv hydrochloric acid kom oxidized tag nrho thiab yaj. Los ntawm kev tswj hwm cov peev xwm ntawm cov tshuaj, cov hlau muaj nqis xws li nyiaj thiab kub tuaj yeem tso tseg hauv cov seem.

Cyanide Kev puas tsuaj

Cyanide nyob rau hauv cov sludge kub muaj tshuaj lom heev. Chlorination kuj tseem tuaj yeem ua lub luag haujlwm hauv kev rhuav tshem cyanide. Hauv ib puag ncig alkaline, thaum ntxiv cov chlorine-based oxidant (xws li chlorine gas, sodium hypochlorite, thiab lwm yam), cyanide yog oxidized ua ntej rau cyanate thiab tom qab ntawd oxidized ntxiv rau Carbon dioxide thiab nitrogen. Lub tshuab ua haujlwm dav dav yog raws li nram no: Thaum muaj cov kua alkaline, cov chlorine-muaj oxidant ntxiv tsim cov hom xws li OCl⁻. Cyanide (CN⁻) reacts nrog OCl⁻, thiab los ntawm ntau qhov kev cuam tshuam oxidation, nws hloov pauv mus rau hauv cov tshuaj tsis muaj teeb meem.

Daim ntawv thov cov kauj ruam ntawm chlorination txheej txheem hauv kev kho Cyanide Kub Sludge

Kev hais ua ntej

Ua ntej cov txheej txheem chlorination, cov cyanide kub sludge feem ntau xav tau pretreatment. Qhov no yuav koom nrog cov txheej txheem xws li kev sib tsoo kom txo qhov me me ntawm cov sludge, uas tuaj yeem ua rau thaj chaw sib cuag ntawm cov sludge thiab chlorinating tus neeg sawv cev, yog li txhim kho cov tshuaj tiv thaiv. Tsis tas li ntawd, yog tias cov sludge muaj ntau cov impurities uas tuaj yeem cuam tshuam nrog cov tshuaj chlorination, xws li ntau dhau ntawm qee cov hlau oxides lossis sulfides, ua ntej leaching nrog cov reagents tsim nyog yuav raug nqa tawm kom tshem tawm cov khoom cuam tshuam no.

Chlorination Reaction

1.Thawj - theem Chlorination (Impurity Tshem Tawm)

• Hauv thawj theem ntawm cov tshuaj tiv thaiv chlorination, lub hom phiaj tseem ceeb yog tshem tawm cov hlau hauv qab ntawm cov cyanide kub sludge. Cov sludge tau muab tso rau hauv cov hlab ntsha nrog cov kua qaub uas tsim nyog (feem ntau yog hydrochloric acid). Tom qab ntawd, tus neeg sawv cev chlorinating, xws li sodium chlorate, yog maj mam ntxiv. Cov tshuaj tiv thaiv kub, acidity, thiab tus nqi ntawm kev ntxiv cov tshuaj chlorinating yuav tsum tau ua tib zoo tswj. Piv txwv li, qhov ntsuas kub ntawm cov tshuaj tiv thaiv tuaj yeem khaws cia nyob rau hauv ib qho chaw, feem ntau nyob ib ncig ntawm 40 - 60 ° C, thiab cov kua qaub ntawm cov tshuaj hydrochloric acid raug hloov mus rau qhov tsim nyog concentration, feem ntau nyob ib ncig ntawm 1 - 3 mol / L.

• Thaum cov txheej txheem no, oxidation - txo qhov peev xwm ntawm cov tshuaj tiv thaiv kab mob yog saib xyuas. Thaum lub peev xwm ncav cuag ib qho tshwj xeeb (piv txwv li, rau kev tshem tawm qee cov hlau hauv paus, lub peev xwm yuav raug tswj ntawm 400 - 450 mV), cov hlau hauv paus xws li zinc, hlau, thiab ib feem ntawm tooj liab yog oxidized thiab yaj rau hauv cov tshuaj. Lub sijhawm tshuaj tiv thaiv txawv nyob ntawm qhov muaj pes tsawg leeg thiab qhov loj me ntawm cov sludge, feem ntau yog li ntawm 2 - 4 teev.

2.Second - theem Chlorination (Kub thiab nyiaj sib cais)

• Tom qab thawj zaug - theem ntawm impurity tshem tawm, cov seem feem ntau muaj kub, nyiaj, thiab qee qhov seem impurities. Hauv qhov thib ob - theem ntawm chlorination, cov xwm txheej raug kho kom xaiv yaj kub lossis nyiaj. Yog hais tias lub hom phiaj yog kom yaj cov kub, cov tshuaj tiv thaiv tej yam kev mob raug kho kom oxidation - txo cov peev xwm. Piv txwv li, los ntawm kev ntxiv sodium chlorate thiab kho cov acidity thiab kub kom tsim nyog, lub peev xwm tuaj yeem nce mus rau ntau qhov kub tuaj yeem oxidized thiab yaj (feem ntau nyob ib ncig ntawm 1000 - 1050 mV).

• Raws li cov tshuaj tiv thaiv tshwm sim, kub hloov mus rau hauv cov dej soluble chloride complexes hauv cov tshuaj. Cov nyiaj yuav tsim cov nyiaj chloride insoluble nyob rau hauv tej yam kev mob thiab nyob twj ywm nyob rau hauv cov residue. Lub sijhawm tshuaj tiv thaiv rau theem no yuav nyob ib puag ncig 0.5 - 1 teev, nyob ntawm qhov nyiaj kub hauv cov sludge.

Hlau rov qab

1.Gold Recovery

• Tom qab cov kub yaj nyob rau hauv cov tshuaj raws li kub chloride complexes, nws yuav rov qab los ntawm kev txo. Cov tshuaj txo qis xws li sodium sulfite, oxalic acid, lossis hydrazine tuaj yeem siv. Thaum siv sodium sulfite ua tus neeg sawv cev txo qis, cov tshuaj tau hloov kho rau tus nqi pH (feem ntau nyob ib ncig ntawm 1 - 2), thiab tom qab ntawd ntxiv sodium sulfite maj mam. Qhov sib npaug ntawm cov tshuaj tiv thaiv rau kev txo cov chloride complexes los ntawm sodium sulfite yog: 3H₂O + 3Na₂SO₃ + 2HAuCl₄ = 3Na₂SO₄ + 8HCl + 2Au.

• Cov txheej txheem txo kuj tseem saib xyuas los ntawm kev ntsuas cov oxidation - txo qhov peev xwm ntawm cov tshuaj. Qhov kawg - taw tes ntawm kev txo qis tuaj yeem txiav txim siab thaum lub peev xwm ncav cuag ib qho txiaj ntsig (piv txwv li, thawj - theem ntawm kev txo qis siv sodium sulfite, qhov kawg - taw tes muaj peev xwm yuav nyob ib puag ncig 590 - 730 mV). Cov kub precipitated ces lim, ntxuav, thiab qhuav kom tau cov khoom kub ntshiab.

2. Nyiaj rov qab

• Yog tias cov nyiaj tseem nyob hauv qhov seem tom qab thib ob - theem ntawm chlorination, nws tuaj yeem ua tiav ntxiv kom rov qab tau nyiaj. Ib txoj hauv kev zoo tshaj plaws yog kho cov khoom seem nrog cov khoom tsim nyog kom yaj cov nyiaj, xws li siv nitric acid kom yaj cov nyiaj chloride los ua cov tshuaj nitrate. Tom qab ntawd, cov nyiaj tuaj yeem rov qab los ntawm cov nyiaj nitrate los ntawm txoj kev xws li electrolysis lossis txo nrog tus neeg sawv cev uas tsim nyog.

Cyanide - muaj kev kho dej khib nyiab

Cov dej khib nyiab tsim thaum lub sij hawm chlorination txheej txheem ntawm cyanide kub sludge muaj residual cyanide. Yuav kom ua tau raws li ib puag ncig cov qauv, cov dej khib nyiab no yuav tsum tau kho. Alkaline chlorination yog ib txoj hauv kev los kho cov dej khib nyiab no. Hauv ib puag ncig alkaline (pH> 10), chlorine-based oxidant ntxiv rau cov dej khib nyiab. Cyanide hauv dej khib nyiab yog oxidized rau cyanate ua ntej thiab tom qab ntawd ntxiv oxidized rau cov pa roj carbon dioxide thiab nitrogen. Cov tshuaj tiv thaiv yog nqa tawm raws li kev sib xyaw kom zoo thiab lub sijhawm tshuaj tiv thaiv kom ua tiav oxidation ntawm cyanide.

Qhov zoo ntawm cov txheej txheem chlorination

High Metal Recovery Rate

Cov txheej txheem chlorination tuaj yeem ua tiav cov txiaj ntsig zoo ntawm cov hlau tseem ceeb hauv cyanide kub sludge. Los ntawm kev tswj xyuas cov kev mob tshwm sim thiab oxidation - txo qhov peev xwm, nws muaj peev xwm xaiv cov yaj thiab rov qab kub thiab nyiaj, thaum tshem tawm cov hlau tsis huv. Piv txwv li, nyob rau hauv cov txheej txheem zoo - optimized, tus nqi rov qab kub tuaj yeem ncav cuag ntau dua 95%, thiab cov nyiaj rov qab tuaj yeem yog qhov siab, nyob ntawm seb qhov pib ntawm cov sludge.

Siv tau Cyanide rhuav tshem

Raws li tau hais los saum toj no, cov txheej txheem chlorination tuaj yeem ua kom puas tsuaj rau cov tshuaj lom neeg cyanide hauv cov sludge kub. Qhov no yog qhov tseem ceeb heev rau kev tiv thaiv ib puag ncig, vim nws tuaj yeem tiv thaiv kev tso tawm ntawm cyanide rau hauv ib puag ncig, txo cov kev puas tsuaj rau tib neeg kev noj qab haus huv thiab ib puag ncig ecological.

Adaptability rau txawv Sludge Compositions

Cov txheej txheem chlorination qhia tau hais tias muaj kev hloov pauv tau zoo rau cyanide kub sludges nrog cov sib txawv. Txawm hais tias cov sludge muaj cov ntsiab lus siab lossis qis ntawm cov kub, nyiaj, thiab ntau lub hauv paus hlau, kev kho kom haum ntawm cov tshuaj tiv thaiv xws li hom thiab tus nqi ntawm cov tshuaj chlorinating, cov tshuaj tiv thaiv kub, acidity, thiab oxidation - txo cov peev xwm tuaj yeem ua kom tau txais kev kho mob zoo.

Kev sib tw thiab kev daws teeb meem hauv cov txheej txheem chlorination

Cov khoom siv Corrosion

Lub acidic thiab oxidizing ib puag ncig hauv cov txheej txheem chlorination tuaj yeem ua rau cov khoom siv corrosion hnyav. Kev siv cov tshuaj chlorine - muaj oxidants thiab acidic media, tshwj xeeb tshaj yog hydrochloric acid, tuaj yeem ua rau cov hlab ntsha, cov kav dej, thiab lwm yam khoom siv. Txhawm rau daws qhov teeb meem no, cov khoom siv tiv thaiv corrosion yuav tsum tau xaiv. Piv txwv li, cov tshuaj tiv thaiv cov hlab ntsha tuaj yeem ua los ntawm cov khoom siv xws li cov hlau tsis zoo, titanium alloys, los yog kab nrog corrosion - resistant cov ntaub ntawv xws li roj hmab lossis graphite. Kev tshuaj xyuas tsis tu ncua thiab kev saib xyuas cov khoom siv kuj tseem tsim nyog los kuaj xyuas thiab kho corrosion - cuam tshuam cov teeb meem raws sijhawm.

Generation ntawm Toxic By - khoom

Thaum lub sij hawm chlorination txheej txheem, tshwj xeeb tshaj yog nyob rau hauv kev kho mob ntawm cyanide - muaj cov tshuaj, muaj kev pheej hmoo ntawm tsim tshuaj lom los ntawm - cov khoom. Piv txwv li, thaum cyanide yog oxidized, cyanogen chloride, uas yog tshuaj lom, tej zaum yuav raug tsim. Yuav kom daws tau qhov teeb meem no, cov tshuaj tiv thaiv tsim nyog yuav tsum tau tswj nruj me ntsis. Nyob rau hauv cov ntaub ntawv ntawm cyanide oxidation, tuav ib puag ncig alkaline tuaj yeem tiv thaiv kev tsim ntawm cyanogen chloride. Tsis tas li ntawd, cov tshuab ua pa kom raug thiab cov pa kho mob yuav tsum tau muab tso rau hauv qhov chaw tsim khoom kom tsis txhob muaj cov pa phem ntau ntxiv.

Siab zog thiab Reagent Consumption

Cov txheej txheem chlorination feem ntau xav tau qee lub zog rau cua sov, nplawm, thiab cov khoom siv ua haujlwm. Tsis tas li ntawd, kev siv cov tshuaj chlorinating thiab lwm cov tshuaj reagents kuj raug nqi. Txhawm rau txo lub zog thiab reagent noj, kev ua kom zoo tuaj yeem ua tiav. Piv txwv li, los ntawm kev txhim kho cov tshuaj tiv thaiv los ntawm kev ua kom zoo dua cov tshuaj tiv thaiv, txo cov cua sov tsis tsim nyog thiab lub sijhawm nplawm, thiab txhim kho kev siv cov tshuaj reagents los ntawm kev tsim thiab tswj cov txheej txheem zoo dua.

xaus

Cov txheej txheem chlorination yog ib txoj hauv kev zoo rau kev kho cov cyanide kub sludge. Nws ua ke kev rov qab los ntawm cov hlau muaj txiaj ntsig thiab kev tshem tawm cov tshuaj cyanide - muaj cov tshuaj. Txawm hais tias muaj qee qhov kev sib tw hauv nws daim ntawv thov, nrog kev txhim kho txuas ntxiv ntawm thev naus laus zis thiab kev siv cov kev daws teeb meem tsim nyog, cov txheej txheem chlorination tuaj yeem ua lub luag haujlwm tseem ceeb hauv kev lag luam rho tawm kub, ua rau muaj txiaj ntsig kev lag luam thiab kev tiv thaiv ib puag ncig.