The Effect of Microwave Energy on Grindability of a Turkish High-Ash Coal

M.S. Delıbalta, O. Y. Toraman


In the present study, the effect of microwave energy on grindability of high-ash (46.39%) and sulphur (3.99%) Turkish coal has been investigated. Coal samples (-9.52+3.18 mm) was treated by microwave at a frequency of 2.45 GHz with different power levels (0.48-0.64-0.80 kW) and residence times (30-150 s.). In order to determine the crushing/grinding resistance of low ranked lignite coal samples treated by microwave oven, the Impact Strength Index (ISI) test was applied for each treated and untreated sample and compared with each other. Experimental results have shown that significant increases in grindability were achieved when the coal samples were exposed to microwave radiation. The ISI of samples decreased up to 96%.

Key words: Microwave energy; Low rank coal; Crushability; Grindability; Impact strength ındex (ISI)


Microwave energy; Low rank coal; Crushability; Grindability; Impact strength ındex (ISI)

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