Effects of MgO and Fe2O3 Addition for Upgrading the Refractory Characteristics of Magnesite Ore Mining Waste/By-Products

In the context of a circular economy/zero-waste, the conversion of extractive wastes into new products is of particular importance. At the Grecian Magnesite SA mine (Chalkidiki, N. Greece), millions of tons of waste accumulate in the operation field. To achieve these goals, the effect of caustic cal...

Full description

Saved in:
Bibliographic Details
Published in:Clean technologies 2022-12, Vol.4 (4), p.1103-1126
Main Authors: Pagona, Evangelia, Kalaitzidou, Kyriaki, Zaspalis, Vasileios, Zouboulis, Anastasios, Mitrakas, Manassis
Format: Article
Language:English
Subjects:
Ceramics
Circular economy
Environmental impact
Fe2O3 additive
Ferric oxide
forsterite (olivine)
Hematite
Magnesite
magnesite mining waste
Magnesium
Magnesium carbonate
Magnesium oxide
Manufacturing
Mechanical properties
MgO additive
Mine wastes
Mining industry
Natural resources
Olivine
Periclase
refractory products
Thermal resistance
thermal treatment
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In the context of a circular economy/zero-waste, the conversion of extractive wastes into new products is of particular importance. At the Grecian Magnesite SA mine (Chalkidiki, N. Greece), millions of tons of waste accumulate in the operation field. To achieve these goals, the effect of caustic calcined magnesia (MgO) at 10, 15, and 20 wt.% was investigated in combination with 0.5, 1, 2.5, and 5 wt.% Fe2O3 at 1300 °C and 1600 °C for 120 min. The main refractory properties were determined along with the mineralogical content. The morphological examination has been performed by SEM-EDS analysis. The addition of MgO increases the desired olivine and eliminates the unwanted pyroxenes, causing the formation of magnesium-ferrite and periclase. MgO wt.% addition resulted in the decrease of firing shrinkage at 1300 °C but increased with Fe2O3. At 1600 °C, firing shrinkage had a minimum value at the optimum MgO dose. Mechanical strength at 1600 °C achieved a maximum value at the optimum MgO dose plus 5 wt.% MgO and 2.5 wt.% Fe2O3 due to sintering process/magnesioferrite formation. These results indicate that MgO and Fe2O3 upgrade the refractoriness of magnesite mining wastes due to the diffusion of Fe2O3 in MgO excess.
ISSN:2571-8797
2571-8797
DOI:10.3390/cleantechnol4040067