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Show Ansaldo Energia s.p.a. F* I* - CASSANO t I GAS FIRING LNR'lmmdGmt Fig. 12 - Monfalcone #3 NOx/Stack dust versus Reburn stoichiometry SR2 at MCR In 12 burners arrangement W 400 ^. m^* _> * ?-* , -\ I I • OFXXLAK • TtAll . TtA «1 •«*0M • TEAal *t*OM :- 25 omr«M|X) F* 11 - CASSANO f 1 GAS OVER OIL RBRVRNING 0 7 01 0.1 ncOADWt aTOaCMMaaaTK V fOffz) • s t 8 300 150 J00 150 IOC „ ? * 1 ' . ' ^ 0 m A - , -<r\ NO* F*B NO>OFA OuaFfB Qua OFA IS 1/ in n 50 75 0 "I _ 5 As oil firing is concerned, figure 11 shows the N O x and corresponding C O values as a function of secondary stoichiometry in baseline and gas over oil reburning configuration. N O x reduction up to 5 0 % has been reached, starting from L o w N O x burner performances (TEA # 1), while combustion optimization allowed to control the C O and particulate concentration improving both boiler and combustion performances. acauaw aToie»«a»aiTar taa IOT aoewau. FaoNT a aout WALL* 1 .BASELINE • R S 1 • REBcpt E „i x s V-•*! • - i .. L^ar*C oo 8 «> ^> 0 TO] jy^ ^s* \ \ .IW51 + + + + + + icrTaoeaMU. MO 9 + + + + + inuaiia + + + + + + + + + + mo«ii«««««iLi OFA ELEV. mm \- + + 4- +4 + + + +_+ + •JOMT - - L i + + + + + Monfalcone 3 As illustrated in a previous paper [11], after a deep experimental and engineering activity it was possible to obtain N O x emissions as low as 170 -s- 180 mg/Nm3 3 % 0 2 (see fig. 12) in the oil over oil configuration with the plant arrangement illustrated in fig. 13b, which has been assumed as reference design for all the other 320 M W e UP units of the E N E L park firing oil. Fig 13 -Monfalcone #3 : Evolution of combustion system arrangement A - Original Reburn Design - B - Reconfigurated Reburn As expected the most difficult problem to be faced was the control of the particulate matter emissions (opacity) connected with the deep staging required to get the aimed N O x level. Again, as can be seen in figures 14 and 15 type of fuel burnt and type of atomizer played a very important role as well as the E S P performance which, with deep staging, is much more charged than in the original condition (see fig. 16). -7- |