The long-term operation with off-designed coal types brings a power plant significant safe and economic problems on its boiler operation.Aiming at solving the problem,tests are conducted to understand the operational status of the units,to analyze the coal blending problem and to optimize the combustion schemes according to the adaptability of the boiler to different coal types.The test results show that the coal blending should not only simply depend on the calorific value or the volatile contents the unit adaptability to different coal types and the influence of coal type dissimilarity on combustion characteristics should also be considered.In the new coal blending scheme,the anthracite (V~=9.23％) of Pulverizer C in phase I project is swapped with the lean coal of Pulverizer A in phase Ⅱ project,which increases the average volatile contents and reduces the coal type dissimilarity for the phase I project.After the optimization,the vibration of the pulverizer gets better.The average boiler efficiency of the units gets a 0.62 percent improvement and the average coal consumption for power generation gets a 0.65 g/(kW· h) decrease.%针对某电厂长期在非设计煤种下运行,严重影响锅炉安全经济运行的问题,通过试验了解机组运行状态,分析机组的煤炭掺配问题,根据机组对不同煤种适应能力的不同,进行机组的煤炭掺烧方案优化.结果表明:动力配煤不能仅根据煤的发热量或挥发份对煤进行简单的渗混,还应将机组对不同煤种的适应性及煤种跨度对混煤燃烧特性的影响纳入考虑.新的煤炭掺烧方案中,一期机组C磨的无烟煤(Vdaf=9.23％)与二期A磨的贫煤(Vdaf=16.50％)互换,一期人炉煤平均挥发分升高,煤种跨度变小,煤炭掺烧优化后,磨煤机振动现象改善,一期、二期机组锅炉效率平均提高0.62％,发电煤耗平均降低0.65 g/(kW·h).
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