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Show FA, f1.nes (fraction) - (.6S4·SR + 6.76)/100 J:A. overs (fraction) - (16.14 .. 11.49·0FA)/1OO FAM • (J=A.rtnes • mass flow,fines) + (FA.overs • mass now,overs ) FA (lb/mmbru) D FAMI1\1MBTU (7) (8) (9) (10) \Vhcre SR is tho tow stoichiometric ratio for the combustor. OFA is the fns.ction of air supplied as ovenu-e air, FA, fines Is the traction of fines fed to the combustor which ends up as particulate. FA, overs is the lracdon ot large particles red to the combustor which ends up as particulate, FAM is the mass now or nyash, mass flow, fines is the mass flow or fmes (in Ibs) fed to the combustor, PA, oven is the mass now of large particles fed (0 the cowbustor, and MMnTU is the fuel teeJ taLc: tu the combustor on an hourly basis. It should be noted that SR.. OPA, and MMBnJ are c1ircct inputs to the PREP module. As with lignite, the addition of calcium Is accommodated by equations increasing the rate of flyash generation. If the molstW'C content of the bionlass is less than 30 percent, aU of the Cines or undersized pArticles are assumed to 10 to nyash. Equation (7) is set at 1.0 and equation (8) is assunled to hold. However the mndel sets An upper bound of 75 pereent on the distribution of flyash relative to bonom ash in such cases. This upper bound is based upon our experience with bIomass fired spreader·stolcers. When pile burners (i.e ~ Dutch ovens, Dietrich cells) are employed, equation (8) for large panicles is assumed to hold for all (uel particles. The entrainment phenomenon is dominated by the overfltC/underftrc air distribution (27]. Municipal Waste and RQE. In the case or MSW. pile burning is the dominant technology. and panic:ulatc enussions are typically low. The percentage of solid products or conJbustion reponing as nyuh from well operated systems is typically on the order of 13 percent (see Table 4), with 87 percent reponing (as bottom ash [36]. Well operated systems typically have excess air levels of 80~o (SR - 1.8) [S 1]. Given the data available (36. 40. S 1]. the (ollowing approximation can be used: FAM -= (ThtA + MUC) • (0.2 • SR • O.22S) (11) \Vhere TMA i, totAl mats ot .. ch and MUC is \h. mA'1 or unhurnftd C':\rbon. n\i, equation C~UQle, lIuu 60 to '0 per~c'll nr allC c.;urobu~don atr Is supplied u underilUce uir. consistent with CWTent practice [51] . Equstion (10) can then be used to express flyash generation in IbnvtMBru. For RDF. the cridcal variable appears 10 be the degree of ~finement. Where a coarse RDF is produced. the material is shredded :0 <6" nominal size, and only the ferrous metal Is removed. In this casc, typically 35$ of the solids remaining from combustion report as flyash [see 421. When a more refined product is produced, shreddin& can be to <4" nominal size. and most of the ferrous and non· ferrous metals are removed along with the glass and related "heavies". When moderate RDF is generated, the typical flyash/bonom ash disaibution approaches 75%125% [371. Again, these numbers are 10 |