Non-impact of particle size distribution on power generation at a pulverized coal power plant burning low rank Alaska coal

This paper details two combustion tests that were conducted in a pulverized coal power plant in Healy, Alaska, on low rank high volatile content Alaska coal. The intent of the tests was to determine if combustion suffered when coal was ground to a coarser particle size distribution (PSD) than current standards (70% passing − 200 mesh or 74 microns, for bituminous coal). Prior studies had indicated that the higher reactivity of Alaska coal would make up for any loss of combustion due to large particle sizes. The first test (the default power plant setting at that time) had a PSD of 48.8% passing − 200 mesh, while the second test was coarser than that, with only 41.8% passing − 200 mesh. The samples for PSD were taken using ASTM procedures. The two tests burned similar BTUs and had similar combustion. Combustion was measured indirectly through steam and megawatt (MW) generation.