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Page 2 of 8 <br />Mr. Tyler O'Donnell <br />August 11, 2015 <br />TR -05 Response to Questions <br />The following responses are provided to each of DRMS's questions addressed in its May 27, 2015 letter in <br />response to GCC's TR -05 Revision request. Each question has been provided in italics with its response to <br />follow. <br />1) The Division believes it would be beneficial to have a schematic illustration detailing the cement kiln process. <br />Please provide a schematic illustration, which shows how the limestone feed enters the kiln and how the <br />limestone is processed throughout the facility. Please provide enough detail to demonstrate how the kiln <br />baghouse dust is collected. <br />The process flow diagram (PFD) in Figure 1 details a portion of the Portland cement manufacturing process <br />where a part of raw materials from the main kiln baghouse will be removed. As GCC proposed in TR -05 request, <br />the kiln feed materials from the main kiln baghouse will be removed when the raw mill is not is not in operation <br />and/or bypassed from hot kiln exhaust gases. The kiln feed materials removed from the main kiln baghouse, <br />when the raw mill is down, are proposed for beneficial use in the quarry. <br />Figure 2 depicts the overall Portland cement manufacturing process to show how the limestone feed enters the <br />kiln and is processed through the facility. Once the limestone is mined from the quarry area, it is crushed and <br />subsequently mixed with sand and other raw materials to produce kiln feed in a composition ready for <br />calcination. This mixture is fed into the raw mill for sizing. Any available crusher fines which are not suitable as <br />kiln feed are beneficially used in quarry reclamation. Following the raw mill, the sized kiln feed material is <br />mixed in a blending silo, then introduced to the preheater as kiln feed. After the preheater, material enters the <br />calciner, then fed to the kiln where clinker is produced. Once cooled, the clinker is ground with gypsum and <br />limestone in the finish mill to produce cement. <br />The kiln is heated using coal from a burner on the hot end of the kiln and a burner at the calciner. The flue gas <br />from coal combustion runs countercurrent to material flow. The flue gases flow from the kiln through the <br />calciner and preheater, then to the raw mill to pre -heat raw materials. A portion of material from the preheater <br />and raw mill are collected in the kiln baghouse. The purpose of the proposed TR is to remove a small portion of <br />collected kiln feed material from the main kiln baghouse when the raw mill is off-line. The kiln feed from the <br />main kiln baghouse will be transported to the quarry area for beneficial use in reclamation backfill purposes. <br />