By Mixing Different Proportions Of Lignite Combustion Characteristics Experimental Study And Evaluation

At present the integration of coal resources in China is gradually deepening, but the coal market is still in short, the coal for the coal-fired power plant is very shortage, using blended coal combustion technology is an inevitable trend of China’s power plants, Blended coal combustion is an extremely complex process, the index of the blended coal effect each other, In order to improve the boiler combustion condition, we must select suitable coals and the optimal ratio, so it is necessary to study the blended coal’s combustion characteristic. The Xianfeng and Xiaolongtan coal, two common lignite at Yunnan province were selected as the research object, through the TGA to study the seven different of blended coal combustion characteristics, and the optimized ration of blended coals was computed by the TOPSIS method, which is one of the Multi-objective decision-making method. Main contents and conclusions of this paper are as following:1.The Thermo Gravimetric Analyzer was operated with the two single coal and seven blended coal, and the ignition and combustion law were researched and analyzed form TG cures, we know that the ignition characteristic, burnout characteristics, maximum weight loss rate of the blended coals were improved, and the relationship between the blended ratio and improve the degree of blended coal’s combustion characteristic is not a simple linear superposition.2.The flammability index, incombustibility stability index, comprehensive combustion index of the blended coal was calculated to evaluate the blended coal’s combustion characteristics. According to the results, all the indicators of blended coal are better than the single coal, and the results are consistent with the results of the TGA experiment.3.According to the reaction kinetics equation, calculated the different proportions of blended coal’s kinetic parameters, and through the activation energy and frequency factor to study the blended coal’s combustion characteristics. The analysis results show that the activation energy of blended coal between the two single coal’s activation energy, when the Xiaolongtan coal’s proportion is greater than50%, the activation energy of blended coal show a strongly linear decrease, the activation energy of blended coal reaches the lowest point when the Xiaolongtan proportion is90%, so the blended coal’s combustion characteristics can be improved through the two lignite blend.4.From the coal’s nature property, considering incombustibility stability index, Burnout temperature, comprehensive combustion index and the economic unit of operation, the best mixing ratio of seven blend coal programs was conducted by the TOPSIS multi-objective decision.