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coal preparation continued other impurities are then rejected across a Midwestern UniRod screen with 2-inch wire cloth apertures. The Acceleratorprocessed, correctly-sized material passes through the Midwestern screen and rejoins the pre-screened material from the Tabor screen on the collecting conveyor for stockpiling. The oversized and foreign plus 2-inch material that passes through the Accelerator and is rejected by the Midwestern screen reports onto a conveyor to a 75-ton truck refuse loadout bin for disposal. The reject consists of oversized shale partings, carbonaceous shale and bone, pyrites, sandstone rock, mine timbers, hand-held drill bits, pick heads and shovels, pieces of rail used to move the horse drawn coal cars in the mine, and any other debris left in the hand-dug deep mines. Ritchie prefers the Accelerator over a rotary breaker because he can tailor the processing of each type of coal separately through the Accelerator. The simplicity of the variable speed control of the Accelerator allows Beechwood to more effectively control and quickly fine-tune the coal impact breakage for each specific coal seam (low or high HGI coals) as well as frozen coal, while rejecting oversized impurities. "During freezing winter conditions, we can process wet or frozen coal more effectively with the Accelerator than with a rotary breaker," Ritchie said. Unwashed wet coal containing clay sticks and freezes to the inside of the rotary breaker. That slow buildup cushions the impact and results in inefficient coal breakage. "During those three to four months of freezing conditions, it was difficult to keep the rotary breaker screen plates and slope March 2013 sheets from plugging, resulting in the loss of coal with the reject," Ritchie said. "With the Accelerator's operation, the material moves through the unit quickly, so that it doesn't have the retention time as in a rotary breaker to stick and freeze. We can adjust the rotor speeds instantly during operation, for higher or lower impact breakage. I love it for processing!" Ritchie also likes the Accelerator better than a crusher for other reasons. "We can decrease the ash content and size of our coal product without crushing everything," Ritchie said. "Crushed shale and rock reduces the Btus [calorific value] by increasing ash in the product. The Accelerator makes fewer fines and requires less maintenance. We don't have to have a welder come in over the weekends to weld nubs onto crusher rolls." Randy Deal, wash plant superintendent, agrees on the maintenance benefits. "We can change out a set of Accelerator impact grids in about 20 minutes and can replace a complete set of rotor flails in about an hour," Deal said. "Wear-component replacements may only need to be done once or twice a year; generally once a year." Through the use of the Accelerator and by blending various coal types, Beechwood Coal has developed a low-cost operating advantage by producing higher quality coal products to more efficiently meet the unique needs of each of its customers. Ron Tschantz is vice president sales with Imperial Technologies, based in Canton, Ohio, www.imperial-technologies.com. www.coalage.com 37