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Show The fine-ground coal was received from Particle Reduction Service Corp. in 23 steel barrels [total weight of 1900 kg (4200 lb)], and each barrel was sampled. Dry sieving such a fine-ground coal can result in an erroneous size analysis. A wet sieve analysis showed that 99% of the coal was below 44p. Samples from each of the 23 barrels of fine-ground coal were analyzed by the General Motors Corp. (GM) Laboratory, and the results showed that over 99% of the coal in every barrel was below 30p in diameter (Table 3). Also, three fine-ground coal samples were sent to Particle Data Laboratories and one to the Pennsylvania State University, Fuel Science Section. Particle Data Laboratories used the Elzone method of sieve analysis, and its results are included as Appendix A. Pennsylvania State University used a MSA-Whitley Centrifugal Sedimentation Method, and its results are shown in Figure 10. GM, Pennsylvania State University, and Particle Data Laboratories agreed that 99% or greater by weight of the coal particles were below 400 mesh (37u). All three results put the average particle size between lOp and 7p by weight (volume), and Particle Data Laboratories shows between 4 to lu average diameter on a particle number basis. The standard pulverized coal was a preground commercial brand, Seacoal, which was packaged in 100-pound bags. Ultimate and sieve analyses were performed on this pulverized coal by the IGT Analytical Laboratory (Tables 4 and 5). Approximately 4800 pounds of fine-ground coal were burned during about 30 hours of operation with fine-ground coal, including start-up and preliminary trials with various nozzles. Input Conditions The input conditions for the two pulverized fuels after adjustments were made to optimize flame geometry and stability and to obtain stable performance of the fuel feed system are presented in Table 6. 16-20 |