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Show • based on their calculated lignitic factors [(CaO -+- MgO)/Fe203 J. Low-tomedium slagging propensities are predicted for all four samples. With regards to convecti ve pass foul ing, the ash-composi tion-based indices predict a medium-to-high and a low-to-medium nature for the Pittsburgh No.8 and Kentucky No. 11 coals, respectively. These same indices predict a severe fouling nature for both MCL products. However, for both slagging and fouling, ash compositional effects are likely to be outweighed by the significantly lower ash contents of the treated coals. Pilot-scale combustion tests were conducted in the PETC Tunnel Furnace, as the new Fuels Evaluation Facili ty was not available yet. Short-term (4- hour) tests were conducted at a firing rate of one million Btu/hr (60-70 Ib fuel/hr) . A natural gas pilot flame was maintained during all testing because insufficient fuel was available to eliminate fuel flow problems with the MCL products. Table 5 gives the measured emission rates of CO, NOx, S02, and particulates from these tests in Ib/million Btu of coal fired. The SO 2 emissions from the Pi ttsburgh No. 8 and Kentucky No. 11 MCL products were 85% and 95% lower, respectively, than those from their corresponding parent coals. Particulate emissions from the MCL samples were approximately 10% of the parent coal emission rate. The MCL samples produced higher emissions of both NOx and CO than their corresponding parent coals. The higher NOx emissions may result from the higher nitrogen content of the MCL products. Advanced Microbubble Flotation Coals Evaluation of the clean coals produced by advanced microbubble flotation has been ini tia ted and only limi ted resul ts are available. Level 1 analyses have been completed and are presented in Table 6. The samples were received at PETC in the form of wet filter cakes containing 45-5070 moisture. Ash reductions of 60.8% for the Pi ttsburgh No. 8 seam coal, 58.5% for the Illinois No.6 seam coal, and 51.3% for the Upper Freeport seam coal, on a lb/million Btu basis, were achieved. Reductions in the total sulfur were 29.8%, 14.7%, and 32.970 for the Pittsburgh No.8, Illinois No.6, and Upper Freeport seam coals, respectively, on a lb/million Btu basis. Advanced microbubble flotation removed 72.0%, 59.2%, and 60.4% of the pyritic sulfur contained in these coals on the same basis. Proximate analysis results show a 1% to 2% reduction in the volatile matter content of the AMF samples on a dry~ ash-free basis. This small reduction generally is insignificant at the measured volatile matter levels with respect to ignition and flame stability. The composition of ash remalnlng in the cleaned coals is relatively unchanged except for significant increases in the alkali content. The ash fusion temperatures of the clean coal products are nearly identical to those of their corresponding parent coals. Ash deposition propensity was assessed by the application of various slagging and fouling parameters (Tables 7 and 8) . Comparable slagging behavior is expected for a given parent coal and clean coal product because their ash chemistries are very similar. The |