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Show W e will illustrate the use of the MPV-Plus system on the following example, as applied on HC-2 unit. This unit is equipped with F-W low-NOx burners. In these burners, the total secondary air is supplied through a c o m m o n sleeve damper (equipped with an actuator) to the inner and outer channels, and the inner air is taken off the outer channel. Therefore, the outer register affects both the outer and inner air flows. For these burners, the strategy of burner adjustment for N O x reduction involves consecutive moves to minimize inner airflow and to open the outer register only as much as needed, such that the common sleeve damper becomes effective. If the outer register is sufficiently closed, the sleeve damper becomes ineffective. Therefore, the sleeve damper equipped with an actuator was used as the main and convenient means of burner adjustment. When the MPV- Plus system was installed on HC-2, initial testing was done on an individual burner basis by moving the sleeve damper on a burner and observing the response of the corresponding M P V - Plus bars and boiler operating parameters. Each burner was tested, starting from its initial sleeve damper position (based on operator adjustments made using their existing boiler firing experience). From the initial position, the burner sleeve damper was adjusted to the fully open position, then back to within 1 inch of the fully closed position and back to the original position. After each move, the response of the M P V bars and boiler operating parameters were observed and noted. Initially, there were concerns that changes to one burner in a 24-burner furnace would not have effect to be easily measured. These concerns were soon assuaged when it was observed that changes to some burners had a large effect on boiler operating parameters, specifically N O x and C O emissions. The finding that certain burners were having an extensive impact on boiler operation had been suspected based on previous testing, but the difficulty was in finding the high impact burners and adjusting them to obtain the desired operating conditions (i.e. low N O x and C O emissions). The M P V - Plus system provided the tool to find those high impact burners and to visually evaluate the effects of burner adjustments on the burner operation. Based on extensive testing on each burner, its response could be empirically characterized and correlated to its effect on boiler operating parameters. After the burners have been characterized, the next question was how to use that information. Let's illustrate it by an example. W h e n the unit was operating at higher than normal N O x emissions 0.53 lbs/ M M B t u , operators requested assistance in reducing the N O x emissions to acceptable levels. By reviewing the actual MPV-Plus bar height on each burner along with the burner characterizations, it was apparent that 3 high impact burners were operating with high N O x factor. These 3 burners were adjusted and N O x level decreased to 0.45 lbs/MMBtu. Thus, use of the MPV-Plus system allows burner problems to be diagnosed and corrected to maintain environmental compliance. Since the MPV-Plus system characterizes the burners as they interact with one another, different characteristics are expected with different combinations of mills in service. Some observations made in the course of boiler and burner adjustments using the MPV-Plus systems Homer City, are briefly described below. 1. Not all burners respond to register adjustments with sufficient sensitivity. The burner response, terms of the measured N O x , C O and the M P V bar changes, depends on many factors, and one of these factors is the combination of register positions. For example, for the F - W burners, if the outer register is essentially closed, the effect of the sleeve movements could be insignificant. The right combination of registers could be different for different burners and should be determined experimentally for each burner. 11 |