改烧神华煤对制粉系统及锅炉运行的影响

The Impact of Shenhua Coal Changing Combustion on Coal Pulverizing System and Boiler Operation

以天津大港发电厂2号锅炉为对象开展了改烧、掺烧神华煤的试验研究,重点对试验中制粉系统参数如煤粉细度、磨煤机组合方式和磨煤机出口温度的调整和锅炉运行参数如一二次风和氧量控制问题进行了分析,结果表明:煤粉细度R90在30%左右、选择下层的磨煤机组合方式和磨煤机出口温度设定为73℃可以保证锅炉及制粉系统的安全性和经济性;目前锅炉合理的运行氧量应该为3.0±0.2%,但锅炉磨煤机风量测量系统的准确性及二次风门开度、燃烧器摆角的一致性需要进行优化改造,以解决锅炉排烟温度较高和再热器受热面壁温不均的问题;加强对炉底漏风的监测和控制。

Experimental study of Shenhua coal changing and blending combustion on No.2 boiler of Dagang Power Plant was carried out, while adjustment of the coal pulverizing system parameters such as pulverizer coal fitness, pulverizer combination and the coal pulverizer outlet temperature, and the control of boiler operation parameters such as the primary and secondary air and oxygen content were analyzed. The results show that: the safety and economy of the boiler and coal pulverizing system can be ensured with the pulverized coal fineness R90 in 30%, selecting the lower coal pulverizer combinations and setting the coal pulverizer outlet temperature at 73 ℃; the reasonable operation oxygen content should be 3.0?0.2%, but the boiler pulverizer air flow measuring system, the secondary air door opening and the consistency of the burner tilt angle should be optimized to solve the problems of higher exhaust gas temperature and uneven distribution of the reheater wall temperature; the bottom air leakage monitoring and control should be strengthened.