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Show NOx, CO AND OPACITY DURING COLD START 10000 20000 30000 40000 STEAM FLOW, PPH Figure 3 C O and opacity were measured as well as all boiler instrumentation; a plot of NOx , C O and opacity is shown in Figure 3. As can be seen the opacity remained within 2-4% during the startup on gas. N O x and C O are corrected to 6 % O2. N O x remained below 80 p p m during the whole startup and C O remained at 50ppm or less. COFIRING RESULTS The University did not need the benefits of cofiring at the time the new burners were purchased, but the future advantages were recognized and it made sense to install the burners in a mode that would allow cofiring. The burners were installed for cofiring but not tuned for cofiring operation. During the summer of 98 an opportunity presented itself to test cofiring on a preliminary basis and see what can be achieved without extensive tuning. The University scheduled particulate and gas analysis testing in preparation for its annual particulate test; extending the tests to measure the effect of cofiring reduced costs. Four tests were scheduled in total all at full load: full coal, 12.5% gas, 2 5 % gas and 37.5% gas. In addition to particulate data, N O x , C O , S 0 2 and full boiler data was taken during each test. During load transitions, some additional data was taken on just opacity and boiler data. Opacity The results from the testing that show the opacity at different load gas quantities is shown in Figure 4. The EFFECT OF GAS COFIRING ON A 70.000LB/HR S T O K ER GAS HEAT INPUT* I9V1 AJFRC SYMPTOM MAUI |