大型CFB锅炉风水联合冷渣器运行问题分析及改进

Analysis and improvement of operation problems of wind-water combined ash coolers for large-scale CFB boiler

风水联合冷渣器运行中普遍存在排渣困难的问题。介绍了某电厂2×135 MW机组技改工程1号锅炉风水联合冷渣器的特点,分析了运行中存在的易堵渣、出渣温度高、风帽和耐磨材料易磨损等问题,指出是由于入炉煤中粗大矸石颗粒过多、排渣管上的旋转给料阀拆除和运行操作不当等原因引起。针对1号炉冷渣器存在的问题,2号炉在设计上增加了冷渣器数量,对冷渣器结构和风源进行了改进;在2号炉调试阶段,采取了严格控制入炉煤粒度、改造刮板输送机和加装隔离门等措施,取得良好的实际应用效果,2号炉冷渣器实现了连续排渣,运行参数稳定。

Wind-water combined ash coolers are widely used in large-scale CFB boilers, and the difficulty in slag discharge is a common problem. The technical features and existing operation problems of the wind-water combined ash coolers of NO. 1 CFB boiler in certain power plant were presented in this paper. Based on the analysis for the problems such as slag blockage, high temperature of slag, abrasion of wind caps and abrasion-resistant materials, main causes were determined, including too many large mining wastes, the removal of rotary feeder and improper operation etc. In view of these problems, the number of ash coolers is increased, the structure and wind source of ash coolers are also optimized. During the commissioning of NO.2 CFB boiler, some countermeasures are introduced such as strictly controlling the granularity of as-fired coal, improving the scraper conveyor and installing isolation valves. All these methods achieved good results. The ash coolers of NO.2 boiler operates stably, and the slag discharging becomes smooth and continuous.