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Show } slagging and fouling tendencies. Additional research is needed, however, to determine how the flame characteristics (flame temperatures, flame radiation, specific heat-release density) and slagging and fouling tendencies change as a function of coal grind before attempts could be made to convert existing boilers and furnaces designed for oil and natural gas firing to pulverized coal. Because these fundamental data are lacking, it is not possible to determine whether the potential benefits of find-ground coal outweigh the added cost of grinding. This study was based on the potential benefits noted above and on the lack of existing information. Development and construction of a milling and feeding system to supply the burner with the proper grind of coal were the first steps of this project. Slag and ash deposition tests were researched and developed. A research furnace was modified and prepared for the coal combustion trials, a boiler burner with a pulverized coal nozzle was installed, and instrumentation with probes was readied. Three different ranges of coal particles were fired, and data were collected on combustion characteristics and on convective pass slagging and fouling. J |