OCR Text |
Show Properties of the Coal The coal was washed product from the Deep Hollow Mine in the Upper Freeport Seam. Proximate and ultimate analyses and forms of sulfur are given in Table 2. The coal was pulverized to 75% passing 200 mesh (75 /-lm) in the C-E Raymond RB-271 bowl mill at the Kreisinger Development Laboratory of Combustion Engineering. The results of a density classification of the pulverized coal by float-sink separation are shown below: Specific Gravity < 1.4 1.4-1.6 1.6-2.2 2.2-2.9 > 2.9 Properties of the Ash Mass Fraction (%) 14.76 78 . 91 4.27 1.46 0.60 The cone fusion temperatures for the coal ash are given in Table 3, and the ash analysis in Table 4. Because a large fraction of the ash feed was retained in the furnace, the average composition of the slag droplets and ash particles approaching the collection tube may be different from the feed. Comparison with the composition of a sample collected at the furnace exit shows that iron, calcium, and phosphorous are slightly depleted in the exit ash due to settling and impaction of dense particles on the furnace walls. The sizes and compositions of particles collected at the furnace exit were determined using Computer Controlled Scanning Electron Microscopy with Automated Image Analysis (Dinger, 1975; Dinger and White, 1976; Moza, Austin, and Johnson, 1979; Hanna, Karcich, and Johnson, 1980; Huggins, Kosmack, Huffman, and Lee, 1980; Kelly, Lee, and Lentz, 1980; Lee, Huggins, and Huffman, 1980; Lee and Kelly, 1980; Huggins, Huffman, 10 |