脱硝系统内横梁结构对催化剂磨损的影响

Impact of Beam Structure on Catalyst Abrasion in the Denitrification System

采用冷态试验与数值模拟相结合的方式,对SCR脱硝装置内催化剂上方的气固两相流动进行了分析.结果表明:横梁结构是导致催化剂磨损的主要原因,气流撞击横梁结构后在催化剂表面形成不同方向的高速含尘气流,对催化剂进行强烈冲刷,最终导致横梁结构两侧下方的催化剂出现不同特点的严重磨损;气流速度是催化剂磨损的主要因素,飞灰质量浓度是次要因素;通过对横梁结构进行适当改造,改善了气流分布,减轻了催化剂的磨损,保证了脱硝装置的经济及安全运行.

Cold test and numerical simulation were combined to analyze the gas-solid two-phase flow over the catalyst in the SCR denitrification device.Results indicate that the abrasion of catalyst is largely caused by the beam structure.After hitting the beam,the air flow forms high-speed dusty air flow in different directions on the surface of the catalyst,strongly eroding the catalyst,which cause serious abrasion with different characteristics on catalysts under both sides of the beam.Air flow velocity is the main cause of catalyst abrasion and fly ash concentration is the secondary cause.By modifying the beam structure in an appropriate way,the air flow distribution is improved and the catalyst abrasion is reduced,resulting in guaranteed efficiency and safety operation of the denitrification device.