Optimization Of Boiler Temperature Field Based On Acoustic Temperature Measurement System

Temperature field of power station boiler is a complex place, in which all kinds of physical changes, chemical reactions, The combustion of pulverized coal, the heat absorption of the working fluid, the generation of NO_x, the formation of the product ash and the slag are all related to the temperature field of the furnace. If the furnace temperature field is destroyed, it will cause a variety of adverse effects on the boiler, may result in over-temperature pipe explosion accident. The furnace temperature measurement is the basis for optimization of temperature field, however, the conventional contact-type temperature measuring device by the furnace temperature limit, it is difficult for a long time, accurate to measure the temperature distribution within the furnace.Aiming at the problems, First of all, starts from the combustion mode of four corner tangentially fired boiler and analyzes several main factors that cause the deviation of the center of the temperature field as well as the important significance of correcting the flame deflection,Starting analyzes the factors affecting NO_x emissions from NO_x formation mechanism and process and Control Strategy in general need to be taken.Then, based on 'Boilerwatch MMP' acoustic measurement system, we conducted a closed-loop temperature field optimization experiments, SAMA configured in the DCS system, temperature field balance and NO_x emission concentration loop optimization control by controlling the size of the secondary throttle opening. After completion of the experiment, the temperature field were well-balanced, NO_x emission concentration were controlled within the allowable range in engineering. Finally, optimization of temperature field data were collected during the experiment, after data processing, use LSSVM establish temperature balance field and NO_x emission concentration model, on the basis of the established model, using genetic algorithm optimization variables, found temperature field were well-balanced, NO_x emission concentration suitable manipulated variable parameter combinations. Modeling and optimization of temperature field balance and NO_x emission concentration, it is the combination of expertise and intelligent control theory, Smart temperature field optimization has laid a theoretical foundation, which is safe and stable operation of the boiler has an important guiding significance.