褐煤锅炉中速磨制粉系统干燥出力计算

摘要

Lignite is the common fuel for power plant in our country and it is usually pulverized by medium speed coal pulverizer. To ensure the medium speed pulverizer to have better drying capacity, thermal balance equation is established according to the first law of thermodynamics. A certain kind of lignite thermal balance under different pulverizer load is calculated. The results show that the important factors influencing the drying capacity are the desiccant quality entering the pulverizer and its initial temperature. Two kinds of pulverizer are compared in terms of drying capacity and it is found that the initial temperature of the desiccant has linear relationship with the air/coal ratio. Based on the trend between desiccant temperature and air/coal ratio from the results, the furnace can adjust combustion situation for more efficiency.%褐煤是我国火力发电的常用燃料，常选择中速磨煤机进行磨制。为保证中速磨煤机有较好的干燥出力，根据热力学第一定律建立磨煤机磨制煤粉时的热平衡方程式，并计算某种褐煤在不同负荷下的磨煤机热平衡，得到磨煤机干燥出力的主要影响因素为进入磨煤机的干燥剂流量及温度，并对选择的两种不同磨煤机进行干燥出力对比，计算结果表明干燥剂初温与风煤比呈现为近线性关系，根据结果拟合得到的曲线可为磨煤机干燥出力及炉膛煤粉燃烧调整提供依据，具有较为实际的应用价值。