zinc stripping from steelwork dust kamil wichterle, jan cieslar, jana wichterlová vsb-technical...
TRANSCRIPT
![Page 1: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/1.jpg)
ZINC STRIPPING FROM STEELWORK DUST
Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava,
70833 Ostrava Poruba, Czech Republic [email protected]
![Page 2: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/2.jpg)
What is the steelwork dust ?
![Page 3: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/3.jpg)
World steel production
Oxygen steelmakingBOF (basic oxygen furnace)
Electric steelmakingEAF (electric arc furnace)
O2
CaO
Direct reduction
Sponge ironFe, (Si,P,S,…)
Iron ore
Blast furnace
Pig ironFe, C, (Si,P,S,…)
Dust30 mil. t /y
2-5 mil. t Zn /y
Steelmaking slag
Steel1 400 mil. t /year
40%
Scrap
Fe0,5%Zn, 0,03%Pb,
60%
![Page 4: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/4.jpg)
Statistics for USA and Canada (year 2000) for EAF mostly (50%): Fe 15-30% Zn 12-25% Pb 1-2% Cd 0,02-0,05%
Dust composition depends mostly on the quality of scrap
In particular our samples from the tandem furnaces Arcelor Mittal contained
Fe about 50% Zn 8-16% Pb 1% Cd 0,02%
Percentage of iron is higher and percentage of the heavy metals is lower in the dust from BOF process (as the heavy metals are absent in the entering pig iron)
![Page 5: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/5.jpg)
1 tonne PRICE
NaOH $ 400 CaO $ 25ZnFe2O4 $ -20
Dust as a basic neutralizing agent
![Page 6: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/6.jpg)
Steelmaking dust processingPyrometalurgy:
Reduction roasting at 1000-2000°C
Distillation of Zn (boiling point 907°C) and its condensation in oxidizing environment in form of ZnO
Hydrometalurgy:
Total dissolution (both Fe and Zn oxides) in conc. H2SO4 or HCl
Hydrolysis at increasing pH in large volume of water leads to iron precipitation = haematite, goethite, or jarosite
Filtration
Chlorine metalurgy:
Reaction of Cl2 or HCl with the dust –chlorides formation
The iron chlorides decompose at higher temperature to oxides and HCl
ZnCl2 (boiling point 756°C) is volatile and it condenses as a water-soluble salt
problems:
problems:
problems:
![Page 7: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/7.jpg)
Experimental studiesof the reactions of HCl with
metallurgy dust VŠB -Technical University of Ostrava
Faculty of Metallurgy and Material EngineeringDepartment of Chemistry
Jan CieslarŠárka LangováJuraj LeškoDalibor MatýsekRadim ŠkutaJana WichterlováKamil Wichterle
![Page 8: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/8.jpg)
The dust in Arcelor Mittal Steel plant is separated by textile filtres and collected as a water suspension
– after a sedimenttion in Dorr thickenners the mud is dumped in deposits
Arcelor Mittal Steel – Tandem Furnaces
![Page 9: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/9.jpg)
Distribution of particle size for the TP dust sample
The dust in Arcelor Mittal Steel plant is collected by textile filtres and transferred to water suspension
– after a sedimenttion in Dorr thickenners the mud is dumped in deposits
![Page 10: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/10.jpg)
Mineralogy of the sample TP
%
w/w% Zn
distribution Zn %
Hematit 3,2
Magnetit 35,6
Wuestit 3,2
Franklinit 36,6 9,9 69,0
Grafit 4,4
Zinkit 5,6 4,5 31,0
amorphous 11,4
![Page 11: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/11.jpg)
Laboratory equipment
Oven
Condenser
Inlet HCl
Quartztube
![Page 12: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/12.jpg)
2 HCl(g) + 1/3 Fe2O3(s) = 2/3 FeCl3(s,l,g) + H2O(g) (1)2 HCl(g) + 1/4 Fe3O4(s) = 1/4 FeCl2(s,l,g) + 1/2 FeCl3(s,l,g) + H2O(g) (2)2 HCl(g) + FeO (s) = FeCl2(s,l,g) + H2O(g) (3)2 HCl(g) + ZnO (s) = ZnCl2(s,l,g) + H2O(g) (4)2 HCl(g) + 1/4 ZnFe2O4(s) = 1/4 ZnCl2(s,l,g) + 1/2 FeCl3(s,l,g) + H2O(g) (5)2 HCl(g) + ZnFe2O4(s) = ZnCl2(s,l,g) + Fe2O3(s) + H2O(g) (6)FeCl2(s,l,g) + ZnFe2O4(s) = ZnCl2(s,l,g) + Fe2O3(s) + FeO (s) (7)2/3 FeCl3(s,l,g) + ZnFe2O4(s) = ZnCl2(s,l,g) + 4/3 Fe2O3(s) (8)
EQUILIBRIUM DATA
-80
-40
0
40
80
200 400 600 800 1000
Temperature, °C
Gib
bs
ener
gy,
kJ/
mo
l
Eq.(1) Eq.(2) Eq.(3)Eq.(4) Eq.(5) Eq.(6)Eq.(7) Eq.(8)
![Page 13: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/13.jpg)
Evidently, iron chlorides are unstable at temperatures higher than 300°C.
Zinc chloride is generally chemically stable up to 700°C
However, ZnCl2 at higher temperatures leaves the reaction space as a vapor (its boiling point is 756°C) which affects the equilibrium
![Page 14: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/14.jpg)
Therefore, higher temperatures
are suitable to separate ZnCl2 vapors from the solid residuum of iron oxides
![Page 15: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/15.jpg)
Zn, Fe, and HCl conversions as functions of temperature for the TP dust sample (45 minutes reaction)
0
10
20
30
40
50
60
70
80
90
100 200 300 400 500 600 700 800 900
T [°C]
X [
%]
X(Zn)
X(Fe)
X(HCl)
X(Zn)+X(Fe)
![Page 16: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/16.jpg)
0,0
20,0
40,0
60,0
80,0
100,0
0 10 20 30 40 50
t [min]
X [
%]
X(Zn)
X(Fe)
X(HCl)
Zn, Fe, and HCl conversions as functions of reaction time for the TP dust sample (temperature 900°C)
![Page 17: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/17.jpg)
World steel production
Oxygen steelmakingBOF (basic oxygen furnace)
Electric steelmakingEAF (electric arc furnace)
O2
CaO
Direct reduction
Sponge ironFe, (Si,P,S,…)
Iron ore
Blast furnace
Pig ironFe, C, (Si,P,S,…)
Dust30 mil. t /y
2-5 mil. t Zn /y
Steelmaking slag
Steel1 400 mil. t /year
40%
Scrap
Fe0,5%Zn, 0,03%Pb,
60%
![Page 18: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/18.jpg)
World zinc production
2009 8 millions tonnes Zn
China (continental) 2.9
Peru 1.4
Australia 1.3
United States 0.7
Canada 0.7
Zinc lossed in steelmaking dust:
3 millions tonnes of Zn !!!!!!1 tonne of Zn = $ 1500 - $ 2500 (2009-2010)
![Page 19: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/19.jpg)
Efficient way of zinc recycling is worth to be studied
![Page 20: ZINC STRIPPING FROM STEELWORK DUST Kamil Wichterle, Jan Cieslar, Jana Wichterlová VSB-Technical University of Ostrava, 70833 Ostrava Poruba, Czech Republic](https://reader036.vdocuments.site/reader036/viewer/2022081519/56649e315503460f94b22c4c/html5/thumbnails/20.jpg)
Thank you for the attention