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Show 4~ \1-.. J";~c. ,.>.J v- Two air-cooled deposition probes are available in the convective section (simulating secondary superheater and reheater tubes) in order to allow for fouling (deposition) studies to be performed. These probes are equipped with thermocouples for measuring metal wal'l and inlet/outlet air temperatures. The probe metal temperatures are maintained at typical boiler tube temperature in order to assure meaningful ash deposition results. The effect of ash deposition on heat transfer is determined by energy balance calculations for each probe. In addition, a simulated commercial sootblower is available to determine the required sootblower pressure necessary to remove the deposits and restore maximum heat flux potential. PILOT-SCALE RESULTS The pilot-scale cyclone project reported herein includes the baseline and reburning tests. The baseline tests are performed under normal cyclone operating conditions and identify the benchmark data to which the subsequent reburning test results are compared. The reburning tests involved the installation/operation of two reburning burners and two OFA ports (at two different elevations). The reburning burners have the flexibility of varying the degree of mixing via changing reburn fuel injector type, spin vane location/angle, and addition of FGR. Critical data collected for both the baseline and reburning phases include NOli' CO, 02' and unburned combustible levels. In addition, gas temperature profiles throughout the furnace were measured. All the tests were perfonned while utilizing a Pennsylvania Kittanning seam coal as the main cyclone fuel. The same Kittanning coal ground to 85% <200 mesh was utilized during the coal reburning tests. The coal, oil, and natural gas analyses are shown in Table 4. The following describes the results of these tests. Table 4 FUEL ANALYSIS Kittanning Seam 2 Fuel Oil As-Received Qiy E(Q~irnale ~oal:isis °Lc;z Moisture 5,62 Volatile Matter 35.35 37.45 Fixed Carbon 49,31 52.25 Ash 9.72 10.30 Gross Heating Value, 12,580 13,330 18,509 Btu per Ib Btu per Ib (M&A Free) 14,860 Uttirnate AOalysis % Moisture 5.62 Carbon 69.93 74 .09 88.25 Hydrogen 4.77 5.05 10.70 Nitrogen 1.42 1.50 0.22 Sulfur 2.55 2.70 0.78 Ash 9.72 10.30 0.05 Oxygen (Difference) 5.99 6.36 0.00 Total 100.00 100.00 100.00 Natural Gas: 88.27% methane, 5.27% ethane, 1.72% propane , 3.6% nitrogen, 1.14% others 8 |