Combinatorial Optimization of Pulverizers for Blended-Coal-Fired Power Plant

Coal blending has become an important way to ease the tension of coal purchase for many Chinese power plants. Mixed by pulverizers which has been widely used, is considered the most reasonable and convenient approach of coal blending. The implementation of this approach meet three main problems, that is to determine the optimum coal blending formula, to select the pulverizer combination for single coals and to allocate the outputs of pulverizers. Previous scholars have done a lot research on the model and algorithm of the first problem, but the latter two which were lack of theoretical guidance, rely mainly on experience in the application. To remedy this situation, a novel model of pulverizer optimization based on new indicators characterizing the burnout and slagging characteristics, the property of stable combustion at low load and pollutant emissions characteristics among different pulverizer combinations, was proposed in this paper. The model contains the pulverizer-coal combination optimization and optimum output of each pulverizer, which are solved by exhaustive algorithm and non-dominated sorting genetic algorithm II(NSGA-II) respectively. It has now been successfully applied in the Dynamic Coal Blending Optimization System of Guangdong Red Bay Power Plant.