The thermal treatment of coal blends prior to coking together with other measures (partial briquetting, stamping of a coal blend, selective pulverization of coal components) is regarded as one of the most promising paths for increasing the efficiency of the laminar coking process (1). Upon thermal treatment of coal blends their moisture decreases and the density of the charge increases, which reduces the consumption of heat in the process and increases the capacity of coke ovens. Moreover, the thermal activation of the most mobile constituents of coal organic matter (bitumens) leads to the improvement of the caking power of coal blends, which contributes to the upgrading of coke quality even when the amount of weakly caking coals in mixes is increased.As has been pointed out by Ruschev (2), the problem of bitumens and their role in the caking of coals is one of the long-standing problems in coal chemistry. As far back as the turn of the century (at the end of the 19th and the beginning of the 20th century) it was established that the removal of bitumens from coal results in the loss of caking properties and their addition to noncaking coals stimulates the formation of caking capacity. According to Dryden (3), the yield of bitumens increases upon extraction of coals heated in an inert medium at 200-400 deg C.
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