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Show ABSTRACT The realities of boiler operation at the end of the 20th Century require that the boiler run as clean as possible. N o more are w e allowed startup opacity spikes, no more soot blowing opacity spikes, N O x and S 0 2 can be sold as commodities on the open market and downwind states require upwind operators to clean up their smog. W e all breathe the same air and it seems like there is less and less. Forward looking boiler operators are looking for solutions to these problems at the lowest cost. Up to now, stoker boilers have been grandfathered and have been allowed to operate within certain limits. The application of continuous opacity monitors has sharpened the dialogue with state regulators to look for solutions. One of these solutions is the installation of a small gas burner in the upper furnace. This burner can be used for boiler warm up, cold start up or shut down; but it can also be used to reduce NOx , S 0 2 and particulates. This paper presents actual results from a single burner installed in the upper furnace of a 70,000 LB/hr stoker boiler. The results are a preliminary snapshot without any tuning or optimization of the process. INTRODUCTION For many years, the stoker boilers at The University of Notre D a m e were started up like most stoker boilers; wood was piled on the grate and lit with oil. When the fire was burning well, the coal was added. The coal was slowly added to increase the fire and warm up the boiler so as not to damage the tubes or overheat the headers. This process continued until the unit was warm and 1WK AJFRC SYMPOSIM MAUI enough burning coal was on the grate to sustain a good hot fire. The boiler was warm and flow was established in the superheater. At that point, the boiler could be brought up to 5 0 % load and set in automatic operation. This 5-10 hour process, even with the most experienced operator, would normally result in opacity exceeding the 4 0 % allowable during startup. With only one start per year, it was not a problem until recently. A number of events put the University in a situation where they had to solve the opacity problem. • Opacity monitors were required • The University felt it needed to project a green image • The state of Indiana was strictly enforcing its opacity laws The University reviewed its options and set upon a series of planned activities to resolve the problem. It cleaned, repaired, and upgraded the multiclone ash filter at the boiler exit. The ash reinjection system was disabled and removed and a new overfire air system designed by Maurice Kelsey was installed. Maintenance had always been a continuous process and the boiler was in good shape considering its age. The setting was repaired every year and the lagging kept leak free. Although the activities improved the situation, the final activity was to install a gas cofiring burner in the upper furnace. Maurice Kelsey, the University's Consultant recommended TODD Combustion based on experience and the fast track nature of the project. T om Evans of CSI, TODD's local representative, received the order for a burner windbox, control system, B M S , and gas valves. The system installation |