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Show 3 DESCRIPTION OF MONITORING SYSTEM - EQUI~ENT The integrated Ish monitoring system consists of sets of detecting instruments, namely, -Dirty" Heat Flux rt:ters, ·Clean" Heat Flux ~ters. Pyrometers, Thermocouples and Conventional Boiler Instruments (4.5). All of these are connected to a microco"",uter data acquisition unit and display terminal. The foll()\'ing is a description of the Boundary Dam Unit 13 System of Saskatchewan Power Corporation. Canada. A similar system is also in operation at Alberta Power's Battle River Unit 13. Description of Boundary Dam Unit 13 Unit 13 is a balanced draft, tilting tangential CE Canada type radiant reheat steam generator nom; na 11y rated at 475.000 kg/h and des i gned for an operating pressure of 13.3 MPa. Main and reheat steam temperatures are contro11 ed at 540°C by a combinat i on of burner til t movement and spray attenperation. The unit was designed to burn high fouling Estevan lignite which typically has high moisture (36~). low ash content (10%). low sulphur (0.37%), and a calorific value of 15285 kJ/kg. There are six elevations of burners, in each of four corners. giving twenty-four burners in total. Forty-two furnace wallblowers are divided among four elevations and sixty six retractable sootblowers service superheater, reheater, economizer and air heater tube banks. Furnace Instrumentation The furnace wall ash monitoring systen involves 82 dirty heat flux meters directly installed on the water wall tubes and 13 clean heat flux meters installed in observation door openings. The design and operating principles of the Waterloo heat flux meters is given in reference (6). Briefly, the dirty heat flux meter is welded to the wall surface and measures the actual heat flux that the tubes receive. As the name suggests it is allowed to become dirty or fouled just like the furnace wall. A clean heat flux meter incorporates the same sensing device which is kept clean by purging air. The clean meter indicates the potential or available heat flux at ; ts 1 ocat ; on. By corrp a ri ng the actua 1 (d i rty meter signa 1) to the available (clean meter signal) heat fluxes a measure of the degree of fouling results. Locations of the instruments are shown on Fi gure (2) which shows a foldout of the furnace walls. Dirty heat flux meters were placed within one meter of each stearn wal1b1ower (devices for cleaning off the ash and slag) with additional meters such that all areas of the furnace walls were represented. Clean heat flux meters were arranged at elevations so that each di rty meter woul d have a representat i ve c1 ean meter for cOf1l>ari son at the s arne hei ght. |