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Show at the walls of the furnace. This produced the worst case scenario for destruction efficiency, and was thought to more accurately simulate the conditions in a water wall boiler. In comparison, all of the baseline testing was performed on the uninsulated furnace. Continuous emissions monitoring was performed for NOx, CO, O2 and THC during the refractory-lined burner tests. THC data are not available for test 4 because of the short test duration, and for tests 9 through 12 because they were conducted after the CEM van had departed. The CEM data for those tests are provided from the instruments located at the Zink test facility. As shown in Table 1, the CEM data show that the refractory-lined burner produced minimal CO emissions at most test conditions. The exception was test 10 which was performed on No.2 fuel oil with no staged natural gas firing. The total hydrocarbons averaged about 20 ppmvw on No.6 oil, and less than 10 ppmvw on No.2 oil. NOx emissions varied with fuel type, preheat temperature and firebox temperature, but were generally lower than those of the HPS™ burner. GC measurements were performed on the flue gas to determine the concentration of ethyl benzene and N20 in the stack. No N20 was detected during any of the refractory-lined burner tests. Table 1 shows the results of the destruction efficiency tests. The concentration of ethyl benzene was used to determine the mass emission rate, which was divided by the mass of ethyl benzene that was spiked into the fuel oil to calculate the destruction efficiency. In cases where no ethyl benzene was detected, the detection limit (approximately 50 ppbvw) was used to calculate a minimum destruction efficiency. Discussion of Results The testing of the advanced burner was conducted at conditions intended to duplicate those of the Zink HPS™ burner. Due to the differences in the mounting of the two burners (bottommounted versus wall-mounted) different apparent stack temperatures were produced. However, it is possible that the thermocouple in the stack was exposed to some radiant heat 9 |