Kev tshawb fawb txog txoj kev rov qab los ntawm tooj liab hauv Cyanide Copper Plating Wastewater

1. Introduction

Tsim kom muaj ib hom electroplating uas zoo rau ib puag ncig thiab txuag tau cov peev txheej tam sim no yog ob lub ntsiab lus tseem ceeb rau kev txhim kho kev lag luam electroplating. Hauv qhov xwm txheej ntawm qhov tsis txaus ntawm cov hlau tsis yog ferrous hauv ntiaj teb thiab qhov nce ntxiv ntawm tus nqi ntawm cov khoom siv hlau electroplating, kev siv cov thev naus laus zis txuag tau cov peev txheej tau nyiam ntau qhov kev saib xyuas. Cov tuam txhab electroplating hauv Suav teb muaj keeb kwm kev loj hlob luv luv. Hauv theem pib ntawm kev txhim kho, muaj kev tsis txaus nyiaj txiag thiab thev naus laus zis rov qab. Feem ntau cov chaw tsim khoom electroplating me me tsis paub txog kev rov qab cov khoom siv hlau hauv cov dej khib nyiab electroplating, tsis txhob hais txog kev tshawb fawb txog cov txheej txheem rov qab. Rau cyanide tooj liab plating thiab tooj liab alloy electroplating dej khib nyiab, cov precipitates tsim los ntawm divalent tooj liab tom qab cyanide tawg yog cov khoom me me, ua rau muaj kev nyuaj rau nag thiab sib cais thiab cov nqi siab. Yog li ntawd, nws yog qhov ceev ceev los kawm cov txheej txheem rov qab tshiab.

2. Cov ntsiab cai ntawm txoj kev

2.1 Kev Kho Cyanide Copper Plating thiab Copper Alloy Wastewater

Hauv cov txheej txheem tawg cyanide ib txwm siv sodium hypochlorite, pH ntawm cov dej khib nyiab uas muaj cyanide yuav tsum tau kho kom txog 11 - 12. feem ntau yog los ntawm kev ntxiv sodium hydroxide. Thaum lub sijhawm tawg cyanide, cyanide hloov mus ua Carbon dioxide thiab nitrogen, thiab cov ions tooj liab monovalent raug oxidized mus ua cov ions tooj liab divalent, uas tom qab ntawd tsim cov khoom me me ntawm cov tooj liab carbonate yooj yim uas dai rau hauv cov dej khib nyiab. Kev tso dej ntuj tsim siv sijhawm ntau dua ib hnub tag nrho thiab tseem tsis tuaj yeem ua tiav cov dej nag tag nrho. Yuav tsum muaj ntau cov tshuaj pab coagulant thiab flocculant kom ua tiav cov dej nag tag nrho thiab sib cais. Yav dhau los, thaum tooj liab tsis tau rov qab los, cov dej khib nyiab tom qab tawg cyanide tau sib xyaw rau hauv cov dej khib nyiab uas muaj cov kua qaub, uas tau kho los ntawm txoj kev txiv qaub ntsuab. Cov tooj liab carbonate yooj yim tau adsorbed rau ntawm cov dej nag hauv cov dej khib nyiab thiab thaum kawg ua tiav thiab sib cais.

Cov txheej txheem tshiab cyanide tawg yog ntxiv cov txiv qaub los kho cov pH. Cov pa roj carbon dioxide tsim thaum lub sij hawm cyanide tawg reacts nrog calcium oxide los tsim calcium carbonate. Nyob rau tib lub sijhawm, tooj liab carbonate co-precipitates nrog calcium carbonate los tsim cov khoom loj loj.

2.2 Kev kho lwm cov dej khib nyiab uas muaj tooj liab

Cov divalent tooj liab ions nyob rau hauv acidic ci tooj liab plating khib nyiab reacts nrog txiv qaub los tsim tooj liab hydroxide, thiab sulfuric acid reacts nrog txiv qaub los tsim calcium sulfate thiab dej. Nyob rau hauv tooj liab pyrophosphate plating khib nyiab, pyrophosphate radical thiab tooj liab ions muaj nyob rau hauv daim ntawv ntawm ib tug complex. Thaum kho nrog txiv qaub, pyrophosphate radical reacts nrog calcium oxide los tsim calcium pyrophosphate precipitate, thiab tooj liab ions reacts nrog calcium oxide los ua tooj liab hydroxide.

3. Txheej Txheem Rov Ua Haujlwm

3.1 Cov khoom siv tooj liab muaj cov dej khib nyiab

Cov dej khib uas muaj tooj liab muaj ntau hom xws li cyanide copper plating, copper-zinc alloy, copper-tin alloy, acidic bright copper plating, thiab copper pyrophosphate plating wastewaters. Cyanide copper plating, copper-zinc alloy, thiab copper-tin alloy wastewaters ntws mus rau hauv lub tank kho dej khib uas muaj cyanide, thaum acidic bright copper plating thiab copper pyrophosphate plating wastewaters ntws mus rau hauv lub tank kho dej khib uas muaj tooj liab. Cyanide copper plating thiab copper alloy wastewaters muaj cov tshuaj complexing xws li Sodium cyanide , potassium sodium tartrate, thiab ammonium thiocyanate, uas tsim cov complexes nrog copper ions. Copper plating wastewaters muaj copper pyrophosphate complexes. Cyanide copper plating thiab copper alloy wastewaters suav txog li 90% ntawm tag nrho cov dej khib uas muaj tooj liab, thaum acidic bright copper plating thiab copper pyrophosphate plating wastewaters suav txog li 10%.

3.2 Oxidation txheej txheem ntawm tooj liab complexes

Ua ntej tooj liab rov qab, nws yog ib qho tsim nyog los rhuav tshem cov tooj liab complexes hauv cov dej khib nyiab electroplating thiab oxidize Cu⁺ ions rau hauv Cu²⁺ ions. Kev sib xyaw ua ke ntawm sodium hypochlorite tov thiab hydrogen peroxide yog siv los rhuav tshem cyanide thiab complexing agents xws li potassium sodium tartrate. Muaj peb lub tso tsheb hlau luam cyanide tawg. Cov dej khib nyiab uas muaj cyanide thiab tooj liab uas muaj cov dej khib nyiab tau muab tso rau hauv thawj theem cyanide-breaking tank. Cov kua txiv qaub yog ntxiv los kho cov pH rau 11 - 12. thiab cov kua txiv qaub ntxiv yog kho los ntawm pH tswj system. Nyob rau tib lub sijhawm, sodium hypochlorite tov yog ntxiv los rhuav tshem cov cyanide. Hydrogen peroxide yog ntxiv rau theem thib ob cyanide-breaking tank kom txuas ntxiv rhuav tshem cov cyanide thiab oxidizing complexing agents xws li potassium sodium tartrate. Vim tias cov tshuaj tiv thaiv qeeb qeeb, ib theem thib peb cyanide-breaking tank ntxiv. Nyob rau hauv lub thib peb-theem cyanide-breaking tank, tshem tawm ntawm cyanide thiab complexing agents xws li poov tshuaj sodium tartrate raug soj ntsuam raws li tshuaj ntsuam xyuas cov ntaub ntawv thiab kev paub. Tom qab ua tiav ntawm cov tshuaj tiv thaiv oxidation, Cu⁺ hauv cov dej khib nyiab tau hloov pauv mus rau Cu²⁺, thiab cov tooj liab carbonate thiab tooj liab hydroxide precipitates tau tsim. Thaum cov txheej txheem no, tom qab tooj liab pyrophosphate plating cov dej khib nyiab reacts nrog txiv qaub, lub complex tsim los ntawm tooj liab thiab pyrophosphate radical tawg, thiab tooj liab hydroxide yog tsim. Cov ntaub ntawv txheeb xyuas qhia tau tias cov txheej txheem no tuaj yeem ua rau cov dej khib nyiab ua tau raws li cov qauv kev tso tawm. Ntxiv txiv qaub los kho cov pH thiab precipitate tooj liab ions txo cov nqi kho mob, thiab txiv qaub kuj plays lub luag hauj lwm ntawm ib coagulant pab thiab tag nrho precipitates pyrophosphate radical.

3.3 Copper Recovery

Hauv cov txheej txheem saum toj no, cov tooj liab ions hauv cov dej khib nyiab electroplating tau hloov mus rau hauv cov tooj liab carbonate precipitates. Yog tias cov txiv qaub ntxiv loj, cov tooj liab ions tuaj yeem hloov mus rau hauv tooj liab hydroxide precipitates. Txij li cov txiv qaub yuav tsum tau los ua kom cov pyrophosphate radical nyob rau hauv tooj liab pyrophosphate plating cov dej khib nyiab, cov txiv qaub ntxiv tsis tuaj yeem tsawg dhau. Tus nqi ntawm txiv qaub yog tsawg heev, thiab nws tuaj yeem muab ntxiv rau qhov tsim nyog tshaj thaum lub sijhawm kho.

Tom qab cov dej khib nyiab uas muaj cyanide thiab tooj liab raug kho nyob rau hauv peb-theem cyanide-breaking tanks, lawv ntws mus rau hauv lub flocculation tank. Sodium pyrosulfite tau ntxiv rau hauv lub tank flocculation kom txo cov hydrogen peroxide ntau dhau, thiab polyacrylamide flocculant ntxiv los ua kom cov khoom precipitate loj tuaj. Yog hais tias sodium pyrosulfite tsis ntxiv rau lub flocculation tank, cov seem hydrogen peroxide tom qab cyanide tawg decomposes tsim oxygen, uas yog adsorbed rau saum npoo ntawm precipitate hais thiab ua rau precipitates ntab. Tus nqi ntawm sodium pyrosulfite ntxiv yuav tsum yog xws li tias cov nag lossis daus tsis ntab, thiab qhov tsim nyog tshaj yog txaus.

Tom qab dhau los ntawm lub flocculation tank, cov dej khib nyiab ntws mus rau hauv lub inclined tube sedimentation tank. Tom qab cov precipitates tau sib cais los ntawm cov dej, lawv nkag mus rau hauv cov sedimentation thickening tank, thiab ces lim los ntawm lub lim xovxwm. Lub ncuav mog qab zib lim tau zoo, thiab cov lim dej rov qab mus rau lub tank hloov. Lub ncuav mog qab zib uas muaj tooj liab zoo yog yuav los ntawm lub tuam txhab kev tshaj lij thiab xa mus rau cov chaw tsim khoom lag luam los tsim cov tooj liab sulfate lossis tuaj yeem siv los tsim cov tooj liab electrolytic.

4. Cov txiaj ntsig

Cov dej khib uas muaj tooj liab tau tsim tawm hauv plaub lub chaw ua haujlwm electroplating. Cov ntaub ntawv tshuaj xyuas thiab saib xyuas qhia tau tias qhov nruab nrab ntawm cov tooj liab hauv cov dej khib Cyanide yog 345mg / L, uas yog, txhua tuj ntawm cov dej khib muaj 0.345kg ntawm tooj liab. Tag nrho cov dej khib cyanide tooj liab txhua hli yog kwv yees li 4600t, muaj 1587kg ntawm tooj liab. Ua ke nrog tooj liab hauv lwm cov dej khib uas muaj tooj liab, kwv yees li 1700kg ntawm tooj liab tuaj yeem rov qab tau txhua hli. Lub tuam txhab cov nyiaj tau los txhua hli los ntawm kev muag cov sludge uas muaj tooj liab yog RMB 30.000 - 40.000. Lub tuam txhab rov qab tau tooj liab los ntawm cov dej khib electroplating zam kev siv tooj liab tsis zoo, tsis yog tsuas yog txo cov nqi electroplating xwb tab sis kuj txo cov pa phem thib ob ntawm cov sludge electroplating rau ib puag ncig, ua tiav cov txiaj ntsig zoo rau kev lag luam thiab kev sib raug zoo.

5. xaus

Kev lag luam electroplating yog kev lag luam uas muaj kuab lom heev. Nyob rau hauv cov xwm txheej tam sim no uas cov txheej txheem kev kho mob thiab thev naus laus zis rau electroplating cov dej khib nyiab hauv Suav teb yog qhov rov qab, nquag kawm txog cov txheej txheem rov qab ntawm cov hlau tsis muaj hlau hauv electroplating cov dej khib nyiab yog qhov tseem ceeb rau kev tsim cov peev txheej txuag thiab ib puag ncig tus phooj ywg electroplating hom thiab tswj kev txhim kho kom ruaj khov ntawm kev lag luam electroplating. Cov txheej txheem ntawm kev kho cov cyanide tooj liab plating thiab lwm cov dej khib nyiab tooj liab kom rov qab tau tooj liab siv cov txiv qaub tau kawm hauv daim ntawv no tau pom cov txiaj ntsig zoo hauv kev siv tswv yim, muab txoj hauv kev ua tau zoo rau kev tsim ntsuab ntawm kev lag luam electroplating.