燃煤锅炉冷灰斗结焦原因及对策

Causes and Countermeasures of Ash Hopper Slagging in the Coal-Fired Boiler

针对3台锅炉冷灰斗斜面均出现结焦情况,调整磨煤机分离器挡板角度使煤粉细度接近设计,再调整磨煤机入口一次风量,保证合理的一次风粉管风速及其出口温度,优化磨煤机运行参数,并通过调整主燃烧区二次风和燃尽风挡板开度、炉膛出口氧量和运行负荷,考察锅炉在不同工况下的安全性与经济性。试验结果表明：清除冷灰斗上面的浇筑料降低了炉膛的温度场;锅炉在均匀配风方式下,炉内燃烧情况较好,飞灰含碳量较低,排烟温度较低,炉效较高;高负荷下,炉膛氧量宜控制在4.0%~4.5%。

For ash hopper slagging in all the three boilers, adjust the angles of the separators baffle of the coal mills to make the fineness of pulverized coal close to the designed value; adjust the primary air flow of the coal mill inlet to ensure the reasonable primary air velocity and the outlet temperature and optimize the operating parameters of the coal mills; adjust the opening of the secondary air and burning wind baffle in the main com- bustion zone, the oxygen amount and operation load of the furnace outlet, and test the safety and economy of boiler under different conditions. The results reveal that the temperature field of the boiler was reduced by clearing pouring material above ash hopper. Under the condition of even distribution of wind, the combustion of the furnace was better with lower carbon content of fly. ash, lower exhaust temperature, and higher efficien- cy. Under laigh load, the oxygen content should he controlled around 4.0 % to 4.5 %.