关键词: 烟气轮机, 轮盘, 冷却蒸汽, 脉冲, 结垢, 蒸汽品质, 振动, 轴承箱

Abstract:

The pulse operation is implemented by cooling steam on the flue gas turbine disk to solve online the problem of scaling in the flue gas turbine that affects the safe and long-term operation of the unit. Attempt to adjust the cooling steam flow rate of the flue gas turbine disk and pulse change the disk temperature. By utilizing the difference in expansion coefficient between the catalysts fouling layer and the disk metal, the fouling layer changes relatively slowly and has a small rate of change. The fouling layer is separated, falls off, and is blown away from the disk. By controlling the pulse change process of the disk temperature, the impact of operation on the smooth operation of the rotor component is minimized to the greatest extent. The pulse operation process takes into account both the process stability and the descaling effect. The setting is as follows: slowly increase the cooling steam flow rate from the normal amount of 800 kg/h to 1,500 kg/h at a rate of 50 kg/h per 5 minutes, and then reduce it to the normal amount at the same rate. During the process, the temperature of the disk decreases from 320 ℃ to 290 ℃ and then recovers to 320 ℃. Within 1 to 2 weeks after the pulse operation, the vibration of the flue gas turbine shaft gradually decreases to a lower level, and there is no significant change in the following 3 months. The goal of improving the dynamic balance of the flue gas turbine rotor online, reducing vibration, and ensuring a 100% synchronous operation rate between the unit and the device has been achieved.

Key words: flue gas turbine, disk, cooling steam, pulse, scaling, steam quality, vibration, bearing housing