Mineral and Chemical Characterization of Magnetic and Non - Magnetic Products Obtained from Dry Magnetic Enrichment of Lignite Coals

Abstract

The mineral and chemical composition of magnetic (tailing fraction) and non – magnetic (clean coal fraction) products from the dry magnetic separation of coal samples with high ash and sulfur contents obtained from Çanakkale Çan lignite (S1) and Manisa Kula Pabuçlu lignite (S2) were investigated in this study. The feasibility of the dry magnetic separation technique for the separation of the minerals from the coal matrix was identified as the function of coal types and particle sizes. The separation technique depends on coal fragments being weakly diamagnetic, while most of the minerals present in the coal are weakly to moderately paramagnetic. Three particle sizes (coarse-, medium-, and fine-sized) of feed lignite and their magnetic and non-magnetic fractions were separated and characterized. The influence of coal type on the magnetic separation efficiency was determined by the recovery of tailing fractions obtained from S1 and S2 lignites. The particle sizes of S1 lignite were quite lower than S2 lignite. When the fine-sized lignite samples from S1 and S2 were used, the recovery of tailing fractions was the highest compared to other sizes. The mineral compositions of S2 lignite include typically mica, smectite (clay mineral), gypsum, kaolinite (clay mineral), pyrite, quartz, and plagioclase. The results showed that the Permroll High-Intensity Magnetic Separation method for high calorific value and low ash content at the medium-sized particle was more efficient for the S2 lignite sample than the S1 lignite sample.

Keywords

• Mineral in coal
• Chemical composition of coal
• Magnetic properties
• Non-magnetic properties
• Magnetic separation

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