350 MW燃煤机组空预器压差异常分析

Analysis on the Abnormal Pressure Difference in the Air Preheater of a 350 MW Coal-fired Unit

空预器堵塞已是普遍性问题,严重时会影响机组正常运行。针对一台350 MW燃煤机组空预器出现压差异常现象,结合运行数据,从多方面进行综合分析。启机阶段烟温过低投入脱硝系统,喷氨量大,排烟温度低,易形成硫酸氢铵,启机初期造成空预器压差迅速上升,当机组处于连续高负荷工况运行下,空预器压差有下降趋势,随着机组经常性低负荷运行,空预器压差升高趋势明显。

Based on the operation data,the abnormal pressure difference in the air preheater of a 350MW coal fired unit is analyzed in this paper.The analysis discoveres that the pressure difference rises quickly during initial startup of the unit,fall during continuous high load operation and rises markedly during usual low load operation again.