| Autor: |
Mitrašinović, Aleksandar |
| Předmět: |
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| Zdroj: |
JOM: The Journal of The Minerals, Metals & Materials Society (TMS); Sep2017, Vol. 69 Issue 9, p1682-1687, 6p, 2 Charts, 4 Graphs |
| Abstrakt: |
In this work, graphite flakes were used to reduce fayalite slag originated from the pyrometallurgical copper extraction process. Experiments were conducted with a significantly different contact area between graphite and slag at two temperatures, 1300°C and 1400°C. The process was continuously monitored via the concentration change of CO and CO in off-gas. Reduction rate values in experiments where 150-micron-diameter graphite flakes were submerged into the slag and left to float slowly to the top are about four times higher compared with when graphite flakes were dispersed at the top surface of liquid slag. The activation energy for instigating reduction was 302.61 kJ mol and 306.67 kJ mol in the case where graphite flakes were submerged into the slag and dispersed at the surface, respectively. The reduction process is characterized by two distinctive periods: an initial steep increase in the concentration of CO and CO controlled by the Boudouard reaction and a subsequent slow decrease of CO and CO concentrations in the off-gas controlled by mass transfer of reducible oxides from bulk to the gas-slag interface. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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