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Show Trial Results Testing of GNOCIS at Ki~gsno~h began November 1994 and was completed in January 1996. During these tests, the pnmary Interest was to evaluate the performance of GNOCIS especially in 21 ~-----------------------------, Carbon-in-Ash Dunng Final Trials (12 & 14 December 1995) ~O TI------------------------------' 19 17 ~ 15 ~ U) !J' 13 c .~ 11 o -e 9 ~ 7 5 3 \ , 'j 380 --12 Dec (ignore advice) - 14 Dec (take advice) NOx During Final Trials (12 & 14 December 1995) - - · 12 Dec (Ignore advice) - 14 Dec (take advice) i I ,. I 0 200 400 600 800 1000 1200 0 200 ~O 600 800 1000 1200 time/min time/min Figure 5. Kingsnorth I GNOCIS Minimize Carbon-in-Ash regard to its ability to produce recommendations that would result in reduced carbon-in-ash. The final tests of GNOCIS were conducted during four days of testing in December 1995 and February 1996. 15r-------------------------------~ In the December test, GNOCIS was set to give advice so that carbon-in-ash would be minimized and NOx would remain below 390 ppm (the NOx limit for the unit). During one day of trials, the advice would be taken and during the next it would be ignored and the unit 12.5 Q) ~ 10 ~~ C).J::. Q) U) ::";0:s >.!"'i'' 7.5 .... c Q) 0 coO ~ 5 5 2.5 ~ Carbon-in-ash . ......... ;j..... ... . .. ~ .... -. r. f lit r • ~'I\ I' 'V\J~'lrll tilt :. { .~~ . Taking Advice to Minimize NOx (27 February 1996) ; .... ~ .. Bumer tilt run at the non-optimized, normal settings. GNOCIS recommended significant changes in A and E feeder, excess oxygen, and burner tilt. As shown in Figure 7, carbon-in-ash was reduced from 15 percent to near 11 percent with minimal impact on NOx emissions. In the February tests, the objective was modified o+---~--~----~--~----~--~---+ o 100 200 300 400 500 600 time/min Figure 6. Kingsnorth I GNOCIS Minimize NOx to minimize NOx emissions. As shown in Figure 8, NOx emissions were reduced by nearly 10 percent with little effect on carbon-in-ash. CONCLUSIONS A summary of the project and the results to date are as follows: • GNOCIS has been successfully deployed at both Kingsnorth and Gaston. • At both sites, GNOCIS was able to provide advice which reduced carbon-in-ash and improved boiler efficiency significantly, while maintaining or lowering NOx emissions. • Alternatively, GNOCIS was able to provide advice which reduced NO" emissions, at minimal cost to efficiency. 6 70 |