Reduction of Sulfur and Ash from Tabas Coal by Froth Flotation

Document Type: Research Article

Authors

Department of Chemical Engineering, Isfahan University of Technoogy, Isfahan 84156, I.R. IRAN

Abstract

Tabas mines in Iran have coal sources which are suitable for use in metallurgy industries as coking coal. But the high sulfur content of this coal imposes severe limitations on its utilization as the sulfur oxide gases evolved from the combustion of high sulfur coals result in acid rains and corrosion of equipments. In this work, attempts have been made to reduce sulfur from high sulfur coal of Tabas by froth flotation. Laboratory tests were carried out in order to investigate the influence of various collectors, frothers, pyrite depressants and their consumption dosages on ash and sulfur reduction of Tabas coal. The use of kerosene as a collector and pine oil as a frother has decreased ash and sulfur content of coal more than other collectors and frothers. Although use of sodium polyacrylic acid as a pyrite depressant improved the total recovery of coal concentrate but did not enhance the reduction of sulfur.

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