中速磨煤机出口温度提高的安全性评估及对锅炉运行的影响

Security Evaluation of Outlet Temperature Increase of Medium-Speed Pulverizer and Its Impact on Boiler Operation

电厂在制粉系统实际运行中,需要部分加入冷风以调节磨煤机出口温度,因此合理提高磨煤机出口温度有利于进一步提高经济性。对ZGM型中速磨煤机出口温度提高后的安全性进行定量评估,主要是通过磨煤机出口煤粉管的一氧化碳浓度、磨辊轴承润滑油温度和燃烧器喷口壁温的变化趋势这3个方面进行衡量。基于磨煤机在安全运行基础上,进一步研究磨煤机出口温度提高后对制粉性能和燃烧方面的影响,结果表明提高磨煤机出口温度对制粉性能和燃烧都有好处,但应有一定的温度限值,以确保设备安全稳定运行。

In the practical operation of the milling system, cool wind is mixed to regulate the pulverizer outlet temperature, therefore, properly increasing the pulverizer outlet temperattlre is helpful to improve the system economic performance. From the aspects of the CO concentration in the coal pipe, the lubricating oil temperature of the bearings and the wall temperature of the burner nozzles, the security is quantitatively evaluated after the outlet temperature of the ZGM medium-speed pulverizer is raised. Based on the secure operation of the pulverizer, the impacts of the temperature increase on the milling performance and the boiler combustion are studied, which concludes that there should be a limit on the temperature increase to ensure the secure operation of the milling system.