Smelting Jarosite and Sulphur Residue in a Plasma Furnace

Salminen, Justin; Nyberg, Jens; Imris, Matej; Heegaard, Bror Magnus

doi:10.1007/978-3-030-37070-1_34

Cited by 6 publications

(17 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…9 To produce highquality (99.995%) zinc by hydrometallurgical processing, the formation of an iron leach residue is inevitable, and iron removal from the leaching solution is needed before electrowinning. 10 Most hydrometallurgical zinc processes utilize jarosite precipitation for controlling iron levels in the leaching stage. Jarosite has a chemical formula of XFe 3 (SO 4 ) 2 (OH) 6 , where X represents either Ag + , H 3 O + , K + , Li + , Na + , NH 4 + , or 1 / 2 Pb 2+ .…”

Section: Introductionmentioning

confidence: 99%

“…Over the last few years, the annual total amount of zinc production worldwide has been about 13–14 Mt, of which the vast majority, about 85%, is produced by the roasting–leaching–electrowinning (RLE) process . To produce high-quality (99.995%) zinc by hydrometallurgical processing, the formation of an iron leach residue is inevitable, and iron removal from the leaching solution is needed before electrowinning . Most hydrometallurgical zinc processes utilize jarosite precipitation for controlling iron levels in the leaching stage.…”

Section: Introductionmentioning

confidence: 99%

“…The processing of jarosite residue in two-stage high-temperature (1250–1400 °C) treatment has proven to be a promising option for accomplishing both targets: a clean slag and recovery of valuable metals. ,, First, the material is melted under oxidizing conditions to produce an intermediate slag consisting of metal oxides and to oxidize and remove sulfur. In addition, a metal oxide fume containing valuable metals, such as Zn, Pb, Ag, In, and Ge, is formed .…”

Section: Introductionmentioning

confidence: 99%

“…Ideally, the non-hazardous and clean slag that is produced could be used, e.g., for construction purposes. The volatilized valuable metals can be recovered from the fume by a hydrometallurgical process . Promising results, with recovery rates of 90% Zn, 99% Pb, 75–85% Ag, 60–70% In, and 80–90% Ge, have been obtained by treating the jarosite and sulfur residue in a two-stage ArcFume plasma process …”

Section: Introductionmentioning

confidence: 99%

“…This would also help in dealing with the issue of limited availability of land for the stockpiling of hazardous residues. On the other hand, economic reasons, such as increasing landfilling costs in the future and economic benefits from recovering and recycling the valuable metals, are also arousing interest in processing of the residue …”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Processing of a Zinc Leach Residue by a Non-Fossil Reductant

et al. 2023

Self Cite

View full text Add to dashboard Cite

The suitability of a non-fossil reductant in high-temperature treatment of a zinc leach residue was studied in laboratory-scale experiments. The pyrometallurgical experiments carried out at temperatures of 1200–1350 °C consisted of melting the residue under an oxidizing atmosphere to produce an intermediate, desulfurized slag, which was further cleaned of metals such as Zn, Pb, Cu, and Ag, using renewable biochar as a reductant. The aim was to recover valuable metals and produce a clean, stable slag for use as construction material, for example. The first experiments indicated that biochar is a viable alternative to fossil-based metallurgical coke. The capabilities of biochar as a reductant were studied in more detail after optimizing the processing temperature at 1300 °C and modifying the experimental arrangement by adding rapid quenching of the sample (to a solid state in less than 5 s) to the procedure. Modifying the slag viscosity by adding 5–10 wt % MgO was found to enhance the slag cleaning significantly. With an addition of 10 wt % MgO, the target Zn concentration in slag (Zn < 1 wt %) was reached after as little as 10 min of reduction, and the Pb concentration was also decreased relatively close to the target value (Pb < 0.03 wt %). With an addition of 0–5 wt % MgO, the target Zn and Pb levels were not reached within 10 min, but with longer treatment times of 30–60 min, 5 wt % of MgO was enough to decrease the Zn content in slag sufficiently. The lowest Pb concentration achieved with an addition of 5 wt % MgO was 0.09 wt % after a 60 min reduction time.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Processing of a Zinc Leach Residue by a Non-Fossil Reductant

et al. 2023

Self Cite

View full text Add to dashboard Cite

show abstract

Thermodynamic Modeling of Elemental Distributions of Trace Elements in Non-ferrous Iron Residue Hydrogen Reduction

Pankka

Salminen²,

Taskinen

et al. 2023

JOM

View full text Add to dashboard Cite

Every year millions of tons of iron residue are generated as a by-product of zinc production. Stabilized landfilled iron residue contains recoverable metals that could be valorized with further processing. Pyrometallurgical processing allows the recovery of valuable metals while simultaneously producing a clean slag that can then be further utilized. A thermodynamic model was developed with FactSage version 8.0. The focus was on minor element behavior and distribution of elements between phases. Calculations were performed at 1200–1400°C and pressure of 1 atm with both pure H2 and H2-Ar mixtures used as a reductant. Also, the concentrations of Pb and Zn in the input were varied. The results showed that a liquid alloy phase forms consisting mostly of either Cu, As and Pb or Fe, As and Cu. It was noted that a higher Ar total gas amount in reduction decreased the mass fraction of the liquid alloy and increased the evaporation of elements into fume dust. S, Bi, Pb, Ge and Zn were observed to evaporate fully, while As, In, Sb and Ag evaporated only partially. The results need to be verified experimentally.

show abstract