Recovery of Coal fines from Rejects by Column Flotation

Investigations were carried out using column flotation to recover coking coal fines from the tailings generated at flotation plant of one of theoperating washeries. Columns of different diameter designed and developed by RRL, Bhubaneswar were used in these studies. Washabilitiy studies indicated that the tailings have the potential to yield 60% of clean coal at 15.0% ash level. Flotation studies in cell indicated thata product with 16% ash can be obtained at 50% yield from these tailings. Results of column flotation had indicated that the performance of column is superior to cell and close to washability data. Most of the coal values being rejected presently can be recovered by using theflotation column. The results obtained by 100 mm and 220 mm diameter laboratory columns could be reproduced on pilot column of 1000 mm diameter, confirming the validity of design and scale up criteria