200 MW富氧燃煤电厂制粉系统及磨煤机参数研究

针对空气-富氧燃烧兼容运行的大型富氧燃煤电厂制粉系统参数选择和磨煤机选型等问题，开展了研究和分析。采用设计计算和理论分析相结合的方式，研究了高CO2气氛对磨煤机及制粉系统参数的影响，获得了典型煤种在200 MW机组空气-富氧兼容条件下磨煤机出口温度、煤粉细度、通风量和煤粉管道流速等参数。综合考虑堵粉、腐蚀和防爆等情况，一次风氧分压控制在18%，烟气冷凝器出口含水率限制在5%以下，富氧干循环方案磨煤机出口温度控制在77~80 ℃为宜，湿循环方案磨煤机出口温度在95~100 ℃为宜。通过磨煤机及制粉系统选型参数比较分析，提出了相关防磨、防漏、防腐措施。研究结果实现了空气-富氧燃烧兼容运行下制粉系统和磨煤机关键参数的匹配。

Study on Mill and Pulverizing System Parameters of Large Oxy-Fuel Power Plant

In this paper, the research and analysis on pulverizing system parameter determination and coal mill type selection is conducted for the large oxy-fuel power plant compatible with air combustion. By taking the approach of combining design calculation and theoretical analysis, the effect of high CO2 atmosphere on the parameters of the mill and coal pulverizing system is studied so as to obtain the parameters of typical coal such as the mill outlet temperature, coal powder fineness, ventilation volume, pulverized coal pipeline flow rate and so on under 200-MW compatible air and oxy combustion conditions. Considering the pulverized coal jam, corrosion and explosion, etc., the oxygen partial pressure of primary air should be maintained at 18% and the water contents at flue gas condenser outlet should be limited below 5%, while the optimal pulverizer outlet temperature of oxygen enriched dry cycle should stay between 77 ℃ and 80 ℃, and that of wet cycle should be kept between 95 ℃ and 100 ℃. Through parameter comparisons, preventive measures against wearing, leakage and corrosion are put forward. Consequently, the key parameters of coal mill and pulverizing system are tuned well to match each other in compatible air-oxygen combustion operation.