NO171320B - PROCEDURE FOR THE SLAM TREATMENT INCURRED BY ELECTROPLETING METALS - Google Patents
PROCEDURE FOR THE SLAM TREATMENT INCURRED BY ELECTROPLETING METALS Download PDFInfo
- Publication number
- NO171320B NO171320B NO905292A NO905292A NO171320B NO 171320 B NO171320 B NO 171320B NO 905292 A NO905292 A NO 905292A NO 905292 A NO905292 A NO 905292A NO 171320 B NO171320 B NO 171320B
- Authority
- NO
- Norway
- Prior art keywords
- sludge
- nickel
- sulfur
- copper
- added
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 15
- 229910052751 metal Inorganic materials 0.000 title claims description 5
- 239000002184 metal Substances 0.000 title claims description 5
- 150000002739 metals Chemical class 0.000 title claims description 5
- 239000010802 sludge Substances 0.000 claims description 30
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 21
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 18
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 13
- 239000011593 sulfur Substances 0.000 claims description 13
- 239000010949 copper Substances 0.000 claims description 12
- 239000002893 slag Substances 0.000 claims description 12
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 11
- 229910052802 copper Inorganic materials 0.000 claims description 11
- 229910052717 sulfur Inorganic materials 0.000 claims description 11
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 10
- 229910052759 nickel Inorganic materials 0.000 claims description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 9
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 7
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 claims description 7
- 229910052698 phosphorus Inorganic materials 0.000 claims description 7
- 239000011574 phosphorus Substances 0.000 claims description 7
- 150000001722 carbon compounds Chemical class 0.000 claims description 6
- 238000009713 electroplating Methods 0.000 claims description 6
- 238000002844 melting Methods 0.000 claims description 6
- 230000008018 melting Effects 0.000 claims description 6
- 239000000377 silicon dioxide Substances 0.000 claims description 6
- 235000012239 silicon dioxide Nutrition 0.000 claims description 6
- 239000011230 binding agent Substances 0.000 claims description 5
- 229910052681 coesite Inorganic materials 0.000 claims description 5
- 229910052906 cristobalite Inorganic materials 0.000 claims description 5
- 229910052682 stishovite Inorganic materials 0.000 claims description 5
- 229910052905 tridymite Inorganic materials 0.000 claims description 5
- 229910052742 iron Inorganic materials 0.000 claims description 4
- NIFIFKQPDTWWGU-UHFFFAOYSA-N pyrite Chemical compound [Fe+2].[S-][S-] NIFIFKQPDTWWGU-UHFFFAOYSA-N 0.000 claims description 4
- 229910052683 pyrite Inorganic materials 0.000 claims description 4
- 239000005864 Sulphur Substances 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 3
- 150000002506 iron compounds Chemical class 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 claims description 2
- 239000005751 Copper oxide Substances 0.000 claims description 2
- 239000004375 Dextrin Substances 0.000 claims description 2
- 229920001353 Dextrin Polymers 0.000 claims description 2
- 229920002472 Starch Polymers 0.000 claims description 2
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 claims description 2
- 239000000440 bentonite Substances 0.000 claims description 2
- 229910000278 bentonite Inorganic materials 0.000 claims description 2
- 235000012216 bentonite Nutrition 0.000 claims description 2
- SVPXDRXYRYOSEX-UHFFFAOYSA-N bentoquatam Chemical compound O.O=[Si]=O.O=[Al]O[Al]=O SVPXDRXYRYOSEX-UHFFFAOYSA-N 0.000 claims description 2
- 229910000423 chromium oxide Inorganic materials 0.000 claims description 2
- BWFPGXWASODCHM-UHFFFAOYSA-N copper monosulfide Chemical compound [Cu]=S BWFPGXWASODCHM-UHFFFAOYSA-N 0.000 claims description 2
- 229910000431 copper oxide Inorganic materials 0.000 claims description 2
- 235000019425 dextrin Nutrition 0.000 claims description 2
- TXKMVPPZCYKFAC-UHFFFAOYSA-N disulfur monoxide Inorganic materials O=S=S TXKMVPPZCYKFAC-UHFFFAOYSA-N 0.000 claims description 2
- 150000004679 hydroxides Chemical class 0.000 claims description 2
- 229910000480 nickel oxide Inorganic materials 0.000 claims description 2
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 claims description 2
- 239000011028 pyrite Substances 0.000 claims description 2
- 239000008107 starch Substances 0.000 claims description 2
- 235000019698 starch Nutrition 0.000 claims description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 claims description 2
- 239000003638 chemical reducing agent Substances 0.000 claims 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims 1
- 238000005054 agglomeration Methods 0.000 claims 1
- 230000002776 aggregation Effects 0.000 claims 1
- 239000004576 sand Substances 0.000 claims 1
- 239000003760 tallow Substances 0.000 claims 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
- 229910052799 carbon Inorganic materials 0.000 description 8
- 238000001035 drying Methods 0.000 description 7
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 3
- 238000003723 Smelting Methods 0.000 description 3
- 238000003912 environmental pollution Methods 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
- 239000000292 calcium oxide Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229910001385 heavy metal Inorganic materials 0.000 description 2
- 229910052960 marcasite Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- WWNBZGLDODTKEM-UHFFFAOYSA-N sulfanylidenenickel Chemical compound [Ni]=S WWNBZGLDODTKEM-UHFFFAOYSA-N 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- YFLLTMUVNFGTIW-UHFFFAOYSA-N nickel;sulfanylidenecopper Chemical compound [Ni].[Cu]=S YFLLTMUVNFGTIW-UHFFFAOYSA-N 0.000 description 1
- -1 oxide Chemical compound 0.000 description 1
- 150000003018 phosphorus compounds Chemical class 0.000 description 1
- 229910001392 phosphorus oxide Inorganic materials 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 239000003784 tall oil Substances 0.000 description 1
- VSAISIQCTGDGPU-UHFFFAOYSA-N tetraphosphorus hexaoxide Chemical compound O1P(O2)OP3OP1OP2O3 VSAISIQCTGDGPU-UHFFFAOYSA-N 0.000 description 1
- 230000004580 weight loss Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Electrolytic Production Of Metals (AREA)
Description
Den foreliggende søknad vedrører en fremgangsmåte for behandling av slam som dannes ved elektroplettering av metaller. The present application relates to a method for treating sludge which is formed by electroplating of metals.
Ved elektroplettering av metaller dannes det et idet vesentlige hydroksidisk komplekst slam som inneholder verdifulle metaller som nikkel og kobber. I tillegg inneholder slammet en mindre mengde av andre tungmetaller samt fosforforbindelser, jernforbindelser og organiske karbonforbindelser. I tabell 1 er den kjemiske sammensetning vist for et slikt slam som utgjør en blanding av slam fra forskjellige elektropletteringsprosesser. When electroplating metals, a substantial hydroxide complex sludge is formed which contains valuable metals such as nickel and copper. In addition, the sludge contains a smaller amount of other heavy metals as well as phosphorus compounds, iron compounds and organic carbon compounds. In table 1, the chemical composition is shown for such a sludge which constitutes a mixture of sludge from different electroplating processes.
Både på grunn av tungmetallene og de organiske karbonforbindelsene som er til stede i slammet, tillates ikke denne type slam deponert i landdeponi, idet dette vil utgjøre en alvorlig fare for miljøforurensing. Due to both the heavy metals and the organic carbon compounds present in the sludge, this type of sludge is not permitted to be deposited in a landfill, as this would pose a serious risk of environmental pollution.
På grunn av slammets komplekse kjemiske sammensetning har man hittil ikke lykkes i å finne en metode for utvinning av verdifulle bestanddeler av slammet, og samtidig overføre resten av slammet til en form som kan deponeres uten fare for miljøforurensing. Due to the sludge's complex chemical composition, it has so far been unsuccessful in finding a method for extracting valuable components from the sludge, and at the same time transferring the rest of the sludge into a form that can be deposited without risk of environmental pollution.
Det er således et formål for den foreliggende søknad å fremskaffe en fremgangsmåte hvorved de ovennevnte slam kan behandles for å utvinne verdifulle bestanddeler fra slammet og å overføre den resterende del av slammet til en slik form at det kan deponeres. It is thus an aim of the present application to provide a method by which the above-mentioned sludge can be treated in order to extract valuable components from the sludge and to transfer the remaining part of the sludge into such a form that it can be deposited.
Den foreliggende oppfinnelse vedrører således en fremgangsmåte for å behandle slam som oppstår ved elektropletteringsprosesser, hvilken fremgangsmåte er kjennetegnet ved at slammet tørkes ved en temperatur under 600°C for å fjerne vann, flyktige karbonforbindelser og omdannelse av hydroksider til oksider, hvoretter det tørkede slammet blandes intimt med elementasrt svovel eller en svovelinneholdende forbindelse, eventuelt karbon samt jern eller en jernforbindelse og Si02 hvoretter blandingen agglomereres og agglomeratene tilsettes en elektrotermisk smelteovn, hvor agglomeratene smeltes ved en temperatur mellom 1100 og 1500°C hvorved det dannes en sulfidfase inneholdende nikkel og kobber samt en slaggfase inneholdende den vesentligste andel av jernoksid, fosforoksid, Si02 og kromoksid, hvoretter det fra smelteovnen tappes en inert slaggfase og en Ni- og Cu-rik sulfidfase. The present invention thus relates to a method for treating sludge arising from electroplating processes, which method is characterized by the sludge being dried at a temperature below 600°C to remove water, volatile carbon compounds and conversion of hydroxides into oxides, after which the dried sludge is mixed intimately with elemental sulfur or a sulfur-containing compound, optionally carbon and iron or an iron compound and SiO2, after which the mixture is agglomerated and the agglomerates are added to an electrothermal melting furnace, where the agglomerates are melted at a temperature between 1100 and 1500°C, whereby a sulphide phase containing nickel and copper as well as a slag phase containing the most significant proportion of iron oxide, phosphorus oxide, SiO2 and chromium oxide, after which an inert slag phase and a Ni- and Cu-rich sulphide phase are drawn from the furnace.
I henhold til en foretrukket utførelsesform føres gassene som oppstår ved tørkingen av slammet gjennom en etterbrenner for destruksjon av de lettflyktige karbonforbindelser i gassen. According to a preferred embodiment, the gases produced during the drying of the sludge are passed through an afterburner for the destruction of the volatile carbon compounds in the gas.
Ifølge en foretrukket form tilsettes pyritt, FeS2 som svovelinneholdende forbindelse til slammet etter tørkingen. Mengden av tilsatt svovel reguleres slik at totalmengden av svovel i blandingen som tilsettes smelteovnen er tilstrekkelig til å overføre kobber og nikkel-innholdet til kobber- og nikkelsulfid. According to a preferred form, pyrite, FeS2 is added as a sulfur-containing compound to the sludge after drying. The amount of added sulfur is regulated so that the total amount of sulfur in the mixture added to the melting furnace is sufficient to transfer the copper and nickel content to copper and nickel sulphide.
Karbon tilsettes slammet etter tørking slik at totalmengden av karbon i blandingen som tilsettes smelteovnen er tilstrekkelig til å redusere tilstedeværende sulfater til svovel og nikkeloksid og kobberoksid til metallisk form. Metallisk nikkel og kobber vil igjen reagere med svovel og danne nikkel og kobbersulfid, som vil oppsamles i en sulfidfase under slaggfasen. Carbon is added to the sludge after drying so that the total amount of carbon in the mixture added to the smelting furnace is sufficient to reduce the present sulphates to sulfur and nickel oxide and copper oxide to metallic form. Metallic nickel and copper will in turn react with sulfur to form nickel and copper sulphide, which will be collected in a sulphide phase below the slag phase.
Mengden av tilsatt jern enten i form av FeS2, Fe eller Fe203 reguleres slik at man oppnår en lettflytende slagg ved temperaturen som eksisterer i smelteovnen. The amount of added iron, either in the form of FeS2, Fe or Fe2O3, is regulated so that a free-flowing slag is obtained at the temperature that exists in the smelting furnace.
Ved fremgangsmåten i henhold til foreliggende oppfinnelse har det overraskende vist seg at ved regulering av totalmengdene av svovel og karbon i agglomeratene som tilsettes til smelteovnen, vil fosfor i det alt vesentligste bli bibeholdt i oksidform og dermed inngå i slaggen. Den produserte kobber- og nikkelsulfidfase vil dermed ha et meget lavt fosforinnhold og kan dermed opparbeides til metallisk form på kjent måte. In the method according to the present invention, it has surprisingly been shown that by regulating the total amounts of sulfur and carbon in the agglomerates that are added to the melting furnace, phosphorus will essentially be retained in oxide form and thus be included in the slag. The produced copper and nickel sulphide phase will thus have a very low phosphorus content and can thus be processed into metallic form in a known manner.
Ved agglomereringen av blandingen etter tørking og tilsats av svovel, karbon og jem kan det benyttes konvensjonelle bindemidler så som bek/tjærebinder, tallolje, sulfittlut, bentonitt, dekstrin, stivelse og andre. Dersom bindemiddelet inneholder karbon eller svovel, må dette tas hensyn til ved beregning av den nødvendige tilsats av karbon og svovel etter tørking av slammet. When agglomerating the mixture after drying and adding sulphur, carbon and gum, conventional binders such as pitch/tar binder, tall oil, sulphite liquor, bentonite, dextrin, starch and others can be used. If the binder contains carbon or sulphur, this must be taken into account when calculating the necessary addition of carbon and sulfur after drying the sludge.
EKSEMPEL EXAMPLE
Et slam fra en elektroplettering ble tørket ved 550°C for å fjerne vann og flyktige karbonforbindelser. Vekttapet ved tørkingen var 77 %. Sammensetningen av slammet etter tørking er vist i tabell 2. An electroplating sludge was dried at 550°C to remove water and volatile carbon compounds. The weight loss during drying was 77%. The composition of the sludge after drying is shown in table 2.
Det tørkede slammet ble intimt blandet med 35 % Si02, 5 % FeS2,30 % FeO og 2,3 % karbon alt basert på vekten av tørket slam. Blandingen ble agglomerert og tilsatt en elektrotermisk smelteovn og smeltet ved en temperatur på 1300°C. Fra smelteovnen ble det tappet en slaggfase og en sulfidfase. Slaggfasen bestod i det vesentlige av Si02, FeO, CaO og fosfor. Nikkelinnholdef i slaggen var 0,4 % og kobberinnholdet i slaggen var 0,1 %. The dried sludge was intimately mixed with 35% SiO 2 , 5% FeS 2 , 30% FeO and 2.3% carbon all based on the weight of dried sludge. The mixture was agglomerated and added to an electrothermal melting furnace and melted at a temperature of 1300°C. A slag phase and a sulphide phase were drained from the smelting furnace. The slag phase consisted essentially of SiO2, FeO, CaO and phosphorus. The nickel content in the slag was 0.4% and the copper content in the slag was 0.1%.
Sulfidfasen inneholdt 55 % nikkel 10 % kobber 20,0 % svovel og 10 % jern. Fosforinnholdet i sulfidfasen var 0,2 %. The sulphide phase contained 55% nickel 10% copper 20.0% sulfur and 10% iron. The phosphorus content in the sulphide phase was 0.2%.
Disse resultatene viser at det ved fremgangsmåten kan fremstilles en nikkel-kobbersulfidfase med et meget lavt fosforinnhold. These results show that the method can produce a nickel-copper sulphide phase with a very low phosphorus content.
Slaggen inneholder den overveiende del av fosfor som var tilstede i slammet sammen med krom, oksid, jernoksid, kalsiumoksid og silisiumdioksid. Denne slaggen er inert og kan deponeres uten fare for miljøforurensing. The slag contains the predominant part of phosphorus that was present in the sludge together with chromium, oxide, iron oxide, calcium oxide and silicon dioxide. This slag is inert and can be disposed of without risk of environmental pollution.
Claims (5)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NO905292A NO171320C (en) | 1990-12-06 | 1990-12-06 | PROCEDURE FOR THE SLAM TREATMENT INCURRED BY ELECTROPLETING METALS |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NO905292A NO171320C (en) | 1990-12-06 | 1990-12-06 | PROCEDURE FOR THE SLAM TREATMENT INCURRED BY ELECTROPLETING METALS |
Publications (4)
Publication Number | Publication Date |
---|---|
NO905292D0 NO905292D0 (en) | 1990-12-06 |
NO905292L NO905292L (en) | 1992-06-09 |
NO171320B true NO171320B (en) | 1992-11-16 |
NO171320C NO171320C (en) | 1993-02-24 |
Family
ID=19893712
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO905292A NO171320C (en) | 1990-12-06 | 1990-12-06 | PROCEDURE FOR THE SLAM TREATMENT INCURRED BY ELECTROPLETING METALS |
Country Status (1)
Country | Link |
---|---|
NO (1) | NO171320C (en) |
-
1990
- 1990-12-06 NO NO905292A patent/NO171320C/en unknown
Also Published As
Publication number | Publication date |
---|---|
NO171320C (en) | 1993-02-24 |
NO905292D0 (en) | 1990-12-06 |
NO905292L (en) | 1992-06-09 |
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