Impact Raw Material for Production Zinc Oxide in Retort Furnaces

7/23/2019 Impact Raw Material for Production Zinc Oxide in Retort Furnaces

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23. - 25. 5. 2012, Brno, Czech Republic, EU

Fig. 3 Sample Project 1Ab C, Al, Si, Cr, Mn, Fe, Ni, S, O

Fig. 4 Area analysis of chemical elementsfor sample Project 1Ab

The more detailed image of the grain boundaries (Fig. 3) represented the morphological arrangement ofindividual carbides. Next, these carbides were investigated in the more detailed way. The research of the

structure showed that there is the occurrence of chrome oxides (Fig. 4). The chain arrangement is also on

the basis of the Cr, Fe, Ni – spectrum 5. Analysis of sample Project 1Ab showed that the particular phases

are mutually different from the chemical aspect.

Table 3 Chemical composition of the elements for sample Project 1Ab

Spectrum C Al Si Cr Mn Fe Ni

Spectrum 2 10.25 0.63 2.24 22.46 0.88 45.75 17.78

Spectrum 3 8.63 0.61 2.16 22.41 0.95 47.08 18.16

Spectrum 4 19.51 0.59 0.67 55.83 0.83 18.20 4.37

Spectrum 5 14.13 0.63 1.16 49.51 0.92 25.96 7.68

Sum Spectrum 10.27 0.64 2.15 24.92 0.94 44.11 16.98

The area analysis can be used for the much more precise determination of the occurrence of the elements,

which are in the individual modifications and they are normally created on the boundaries of grains (Fig. 4).

Project 1B

Fig. 5 Sample Project 1Ba Fig. 6 Sample Project 1Bb

The detailed observation of the particular areas relating to microstructure (Fig. 5) released that chainarrangement obtains sulphur (S = 0.48%). This area has high weight percentage of Fe, Ni, Cr. The chemical

composition of spectra from 2 to 5 seems to be the same in the contrast to spectrum 6 (tab. 4).



23. - 25. 5. 2012, Brno, Czech Republic, EU

During the production of the ZnO, the primary raw material is seriously influenced by the other

additives. This fact is closely connected with the decrease of lifetime of furnace aggregates as well

as there is the increase of the fuel. The occurrence of the additive or impurities as well as other

unsuitable phases will have the significant influence on the whole technological process therefore

the attention must be paid to the input raw materials.

In the case of the occurrence of the structural phases, which do not contain zinc (but they can

contain the high chemical amount of Cr, Fe and Ni or other elements), it was proved from the

practical aspect that these phases have the negative influence on the whole process. There will be

the occurrence of the unwanted and negative chemical reactions and it will have also the negative

effect in relation to the ceramics of furnace case.

In relation to the selected sample which does not contain zinc (but high chemical amount of Cr, Fe

and Ni or other elements), there is the occurrence of the grains with the different morphology in the

comparison to grains containing zinc. This morphology reflects the occurrence of stress states I the

primary structure and these stress states have following influence on the decomposition of solid

phase. The phase transition of solid phase to gaseous phase will be carried out in the different

places of furnace at different thermal gradients and it has also negative influence on production

process of ZnO.

There is the recommendation to perform much more detailed analysis of the input material as wel as

research interactions of the molten secondary zinc with the other elements and with aggregates of

furnace case.

REFERENCES

[1] International Zinc Association: Zinc Oxide Applications, Begium, 2011.

[2] TOLCIN A.M. Zinc, U.S. Geological Survey. Mineral Commodity Summaries. USA. January 2011.

[3] MCNAMARA, G. Fact-ite. Planet Earth. Earth Sciences for Society. Geological Society of Australia.

[4] LUPTÁKOVÁ, N. and kol. Microstructure Analysis of Zinc and Zinc Alloys. Machine Modeling and Simulations.

2011. ISBN 978-80-8075-494-5.

[5] BS EN 1179:2003: Zinc and zinc alloys - Primary zinc. 2003.

[6] JAREŠ, V. Metalografie neželezných kovů. Česká matice technická. Praha. 1950. 318-319 s.

[7] TRPČEVSKÁ, J. and kol. Spracovanie odpadov zo zinkovní. Katedra neželezných kovov a spracovania odpadov.Hutnícka fakulta. TU Košice.

[8] SEDLÁKOVÁ, Z., HAVLÍK, T. Výskyt neželezných kovov v hutníctve železe a ocele ich možné spracovanie,

TUKE. Katedra neželezných kovov a spracovania odpadov. Acta Metallurgica Slovaca, 12, 2006, 2 p. 209-218.

[9] International Zinc Association: Zinc Oxide Production Technology, Begium, 2011.

[10] KOUDELKA, L., HORÁK, J., JARIABKA, P. Morfology of polycrystalline ZnO and its physical properties. Jourmalof Materials Science. 1994. pp. 1497-1500.

Impact Raw Material for Production Zinc Oxide in Retort Furnaces

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