OCR Text |
Show INSTRUMENTATION All normal boiler pressure and flow data was obtained from the existing control room and local gauges which were calibrated on a regular basis. A considerable number of additional local instruments were utilised to closely monitor the boiler oil, gas, Forced Draught, Induced Draught and Flue Gas Recirculation systems. A rapid response Zirconium oxygen and combustibles monitor and associated recorder was installed to measure the exhaust gas analysis in the superheater zone. This allowed for variation in combustion settings to be monitored with the minimum time delay and with the minimum possible dilution from tramp air leakage. A grid of twelve gaseous sample points were installed in the economiser exit and the exhaust gases from these points continuously monitored during test work for oxygen, CO, C02 and NOx. (See Illustration 10). A purpose designed and built mobile laboratory was utilised to continuously sample and monitor the above flue gases with modern analysis equipment. The laboratory and the method of testing employed allowed for calibration of all instruments against standard gases before, after and during each test. Flue gas SOx was measured as deemed necessary using the controlled condensate method. Total hydrocarbons in the flue gas were measured as required by filling evacuated stainless steel flasks with exhaust gas samples and then having the flasks analysed by gas chromatography and flame ionisation at an independent laboratory. Hydrocarbons were measured as Methane, 5-17 |