锅炉空预器密封间隙控制系统设计及实现

Design and Implementation of Seal Gap Control System for Boiler Air Preheater

对某钢厂自备电厂锅炉工艺流程和空预器结构进行了研究分析,指出了空预器密封结构存在的漏风问题及其对经济运行造成的影响;结合空预器热端径向密封结构改造优化情况,相应地研究设计了密封间隙控制系统,制定了基于西门子PLC控制的改造实施方案,通过增加PLC控制软硬件系统和间隙测量仪表实现了空预器密封间隙的自动调整控制,确保扇形板与转子径向密封片的间隙在设定目标值范围之内,有效降低了空预器漏风率和发电煤耗指标,提高了锅炉热效率,经济效益显著。

The boiler process and air preheater structure of a steel mill's self-provided power plant were studied and analyzed,pointing out the air leakage problems in the air preheater sealing structure and their impact on economic operation.Combined with the optimization of the hot end ra⁃dial seal structure of the air preheater,the seal gap control system was studied and designed accord⁃ingly,and the implementation plan of the modification based on Siemens PLC control was formu⁃lated.By adding PLC control software and hardware system and gap measuring instrument,the auto⁃matic adjustment control of air preheater seal gap was realized,which ensures the gap between fan plate and rotor radial seal piece was within the set target value,effectively reduced air leakage rate and coal consumption index of air preheater,improved boiler thermal efficiency,and achieved sig⁃nificant economic benefits.