摘要
Abstract
In response to the problems of insufficient output of once-through boiler with opposed wall-fired combustion system,large emission of pebble coal,poor coal powder fineness adjustment performance and insufficient uniformity,the components of the upper and middle coal mills were repaired and replaced.To further understand the working characteristics of the medium-speed coal mill,and quantitatively analyze the influence of dynamic separator speed on the operation effect of the coal mill under the economic coal loading mode,internal resistance and flow field optimization experiments were conducted inside the coal mill.Results showed that,the main reason for the decrease in output of coal mill 4F is the high resistance inside the cavity and the uneven distribution of the flow field,after the transformation of the separator,the pressure loss was significantly reduced,and the output has been increased to 53 t/h.The maximum coal consumption of upper coal mills 4A is 48 t/h and 4D is 40 t/h,the middle coal mill 4C can operate stably for a long time at coal rates of 50 t/h.During the speed increase process of the separator of coal mill 4F,the coal distribution uniformity among pipes initially improves but subsequently deteriorates.When the separator speed was 88 r/min,the coal powder amount in each branch pipe was equivalent,the fineness also met the design requirements.After the capacity expansion and efficiency improvement transformation of the coal milling system,the synergistic optimization of the milling output and coal powder quality during the operation of the coal mill has been achieved.关键词
中速磨煤机/动态分离器/内部阻力/流场优化Key words
medium-speed coal mill/dynamic separator/internal resistance/flow field optimization分类
能源科技
