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Show 13 RECENT RESULTS OBTAINED USING THE ASH MONITORING SYSTEM Furnace Section There have been some new findings from the Furnace Wall Ash ft>nitoring System installed in the Saskatchewan Power Plant. Previous results obtained from a similar system were reported in references' (6) and (11). In general. the extent and the tenacity of the furnace deposits observed in Boundary Dam were greater than on other boi 1 ers tested in Al berta and Ontario (11.6). The heat flux absorbed by the walls re9Jlarly fell bel~ 20% of the potential heat fl ux. ft>re important was the fact that some areas were not cleaned at all by the adjacent wallblcwers. particularly just above the burners. An example of this is shown in Figure (10) where the levelS wallbl~ s did not affect dirty meter 5W2. This has serious implications for boiler operation because adequate wall cleaning may not be possible during full load operation and reduced load may eventually result. In some instances where heat is not being absorbed above the burners the boiler can maintain load because the lower surfaces are absorbing much more heat than normally is the case. Whereas at the Battle River Generating Station of Alberta Power the differences in heat absorbed by the lower surfaces varied by a factor of 1.5 (4), in Boundary Dam the heat fl ux vari ed from 50 k Wj~ to 150 kWjm2 a factor of 3 (refer to Figure (11) which shows, at level two, the clean heat flux signal changes from 1.3 to 4.0 mV when the tilt varies due to fouling). It appears that extra surface area has been installed to allOt.' the Boundary Dam unit to continue operation with some surfaces severely fouled. 6~------------------------------------------~ 5 .. ,, .. ', , '\.I. \. ,, 3 \ , , , \ " ..... 2~, \ 0\ ',_, ~~ , , •,,,, ,, \ \ , Sept 9. 1985 " 5 WJ -"-\-_.--. 5 W2 1 ",'A "0,-- -' ~~o ______ -..."...,o----_ o--o~o ~ 1'b ' D'" + • I 10 12 |