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Show 3) emissions values from small scale pilot plants, calibrated to full scale systems; and 4) theoretical data. Emissions data for full scale plants were obtained directly [22, 33, 37, 40, 42, 64] in many cases. Emissions data for full scale plants were also obtained from numerous other publications [see 5, 6, 10, 19, 30, 32, 36, 39]. Pilot plant data were obtained from the following sources: [7, 26, 27, 31, 38, SO]. Once obtained, these emissions data were fitted to equations which not only provided acceptable correlations, but also utilized variables identified by the explanatory combustion models [see, for example, 14, 17, 56]. 3.2. Particulate Emissions Estimation Particulate emissions include ash residues from combustion entrained in the gas stream, char particles from carbonization of fines entrained in the gas stream, and condensed products of pyrolysis. Such emissions vary dramatically from fuel to fuel, even among the low grade energy sources. Lignite particulate emissions are estimated based upon the extensive work of Munro [38]. In this work it was demonstrated that particulate emissions are a function of the percentage fmes in the coal feed, the total quantity of excess air, and the distribution of that air. The critical variable determined by Munro was the stoichiometric ratio at the grate. When the grate or bed stoichiometric ratio was maintained in the region of 0.7 - 0.8, when staged combustion was operating, particulate emissions were minimized. FA Ob/MMBtu) = 1.1S*GSR + 2.S*UNF - .7327 (6) Where FA is flyash emissions, GSR is the grate stoichiometric ratio, and UNF is the fraction of fuel supplied to the system as fmes. Note that this typically holds for lignite and subbituminous coals with ash contents in the region of 3 - 6 percent. Where ash contents are higher, adjustment must be made for inerts being entrained in the gas stream. It should be noted that these equations do not account for limestone injection into the system. If limestone is injected into the combustor for acid gas control, equations exist in the model to adjust the flyash generation rate accordingly. Both reacted and unreacted calcium compounds are always treated as flyash. Biomass particulate emissions from spreader-stokers were extensively studied by Junge [25, 27] and Tuttle [60], as well as Munro [38]. The Junge data are particularly revealing, since they deal with the dominant forces of biomass particulate formation: moisture content of the feed, percentage fines, quantity of excess air, and grate stoichiometry. Funher, the Junge data deal with the trade-off between carbon conversion and fines entrainment under cenain circumstances. The Junge data lead to the following model for approximating particulate emissions from wet (MC>30%) biomass fuel: 9 |