Experment And Research On Coal Distributor And Employing Support Vector Machine To Predict The Ash Fusion Temperature Of Coal Blends

Combustion system is the most important part in boiler system. Economic benefit of power plant is affected by the state of boiler's combustion. Coal ash fusion temperature has large influence on thermal efficiency and clinkering of boiler. Many countries constitute criterion with coal ash fusion temperature to judge propensity of clinkering. In our country, many power plants take coal ash fusion temperature as a very important parameter to estimate coal quality. Coal blending technology is helpful for boiler safe and economical operation. In order to improve the accuracy of the ash fusion temperature prediction. Support vector machine and genetic algorithms were combined to model the ash fusion temperature of coal blends. The chemical compositions of the coal ash were employed as inputs and the ash fusion temperature as output. The results show that the maximum and average relative predicting error were 7.4% and 0.678%, respectively. Support vector machine can find its application in the small sample training, its calculating speed is fast which can improve the real-time processing performance.Pulverized coal distributor effectively controls the distribution of pulverized coal and air, and adjusts the smoke temperature of the furnace outlet by adjusting the distribution of pulverized coal and air. Pulverized coal distributor also avoids or reduces propensity clinking, enhance the steady combustion ability under low load. This paper introduced the theory and knowledge about two phase flow, and summarized the techniques and instruments of measuring concentration of Gas-Solid multiphase flow. The instrument of optical wave method used in experiment was detailed introduced. A commercial CFD software fluent was used to numerical simulate the distribution of pulverized coal and air at the distance of 1D after the entrance under the condition of fork pipe and elbow are parallel installed. The result of this numerical simulate was analyzed and estimated in this paper. The experiments of testing concentration distribution in the fork pipe and in the export pipe of the fork pipe are carried out on large test board. The results of these experiments showed that distance has great influence on the even distribution of pulverized coal and air under the case of fork pipe and elbow are parallel installed when entrance shorter than 5D, but distribution of pulverized coal and air under the case of fork pipe and elbow are vertical installed is good.At last, this paper summarized the study works (include experiment and numerical simulate) and draw a conclusion, discussed some problems which may be existed in the research process, and give some advices on continual researches.