空气气氛下煤质的CO析出特性实验研究

Experimental study on CO precipitation characteristics of coal under air atmosphere

目前,中速磨煤机已被火力发电厂广泛使用,为了防止中速磨在其运行中着火爆炸,运行人员习惯把中速磨的出口温度控制在较低水平。虽然CO浓度变化不是磨煤机爆炸的直接原因,但中速磨内部CO的浓度与磨煤机的着火爆炸有着很强的相关性。采用热重和红外联用的方法,通过不同温升速率持续加热煤粉得到了CO的析出规律。首次提出了CO第一析出温度、第二析出温度概念,并通过恒温加热得到了CO第一析出温度以上或以下时的CO析出特性。CO析出特性的研究对于提高磨煤机运行的出口温度、降低排烟温度,提高锅炉效率有着重要意义。

At present, the medium speed coal mill has been widely used in thermal power plants. In order to prevent the medium speed coal mill from ignition and explosion in its operation, operators are accustomed to control the outlet temperature of the medium speed coal mill ata relatively low level.Although the change of CO concentration is not the direct cause of the explosion of coal mill, the CO concentration in coal mill has a strong correlation with ignition and explosion of coal mill. By the combination of thermogravimetric and infrared method, the law of CO precipitation is obtained by heating coal powder continuously at different temperature rising rates. The concepts of the first and second precipitation temperature of CO are proposed for the first time, and the precipitation characteristics of CO above or below the first precipitation temperature of CO are obtained by constant temperature heating.The study of CO precipitation characteristics is of great significance for improving the outlet temperature of coal mill operation, reducing the exhaust gas temperature and improving the efficiency of boiler.