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Show 2700 I + Blow Soot LL 2600 -0 Q) ~ ::l -ct1 2500 blow 1-8 mill ~ aQ). + problems E Q) 1 ..... 2400 2300 ~ ______ ~ ________ ~ ______ ~ ________ ~ ______ ~ ________ ~ 16 17 18 19 20 21 22 Time (24 hr) 8-6790 Figure 4. FEGT Measurements at Salem Harbor #3, Pocahontas Coal Figure 4 shows the FEGT data for Pocahontas coal fired at full load with all four burner rows. As can be seen, the FEGT is relatively constant. Some variations occur, but the temperature remained mostly between 2400° and 2425°F. Sootblowing only occurred once in this six hour period. In fact on November 15, the IR blowers were only used at 11:15 and then at 20:45. After 20:45 one mill experienced problems, so that further records were not comparable. In any case, the comparison of Figures 3 and 4 show very different behavior. The FEGT for Pocahontas was very stable and was similar to the FEGT when the walls were cleaned when using the baseline coal. The comparison of the FEGT data for the two coals shows a much lower effect on heat transfer of the Pocahontas coal than the baseline coal. This reduction was indicated by both the FEGT measurements and the rate of sootblowing. The reason for the reduction with Pocahontas is due to both a reduction in the rate of deposit buildup, and any changes in the conductivity of the deposits that may have occurred. 4. SUMMARY This paper discusses novel adaptation of optical pyrometry that has been developed for in-furnace temperature monitoring. This non-intrusive, continuous measurement technique is capable of being used in a variety of utility and industrial applications. The technique which is based on measurement of the radiation emitted by ash, char or soot particles has been successfully demonstrated at a number of pulverized-coal-fired utilities where furnace exit gas temperature was monitored. Also, demonstrations for a number of other applications including Waste-to-Energy, post combustion NOx control and industrial 8 |
