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Show Ui o Table 1 Slagging and Fouling Indicies Teat Index Values ___ Fuels 1. Ash Fusion Temperature Initial Deformation (I.D.) Function of ash chemistry All Softening, S.T. (Sph.) S.T. used to select furnace exit Softening, S.T. (Hemp.) Temperature Fluid (F.T.) 2. Tcv Temperature at which viscosity None All changes from Newtonian to Bingham plast ic 3. T2St Temperature at 250 poise Ratings Ratings All (Dry Bottom) T2 i , (Wet Bottom) Low >2325 T2 S , <2600*F Medium 2550 to 2100 High 2275 to 2050 Severe <2200 4. % Basic Constituent £%(Fe,0, + CaO + MgO + Na,0 • K,0) None All 5. Base-to-Acid Ratio (B/A) E2(Fe20, + CaO + MgO + Na,0 + K,0) 0.5 maximum for dry bottom units All £Z(A1,0, + SiO, + TiO,) >0.27 for wet bottom units 6. Rs - Slagging Factor (B/A)U S on dry coal) R„ Slagging Type Eastern coals only 7. Rf, Rf' - Fouling Factor Rf = (B/A)(X Na20 (ASTM ash)] Rs Rf' Fouling Type Eastern coals only Rf' = (B/A)[% water soluble Na,0 from LTA (low temperature ash)) Sodium Content of Coal Ash X Na,0 in ASTM ash Lignit ic Bituminous All Na2Q Fouling % Na20 Foul <2.0 Low <0.5 Low 2-6 Medium 0.5-1.0 Medium 6-8 High 1.0-2.5 High 8 Severe >2.5 Severe R., <0.6 0.6-2.0 2.0-2.6 >2.6 «s <0.2 0.2-0.5 0.5-1.0 >1.0 X Na20 Foul Slagging 1 Low Medium High Severe Rf* <0.l 0. 1-0.25 0.25-0.7 >0.7 ing X IN •ype Low Med ium High Bi tuminous la20 Fouling 9. Alkali Content of Coal Ash l(Z Na20 + 0.6589)(% Kt0) Same as 4 All |
