针对催化重整装置加热炉集合管盲端的腐蚀现象, 运用腐蚀理论对其进行了机理研究。结果表明, 在操作工况下, 出口集合管盲端法兰内侧发生高温硫腐蚀, 富氢环境使腐蚀产物疏松多孔, 在高流速流体冲刷下发生冲刷腐蚀。采用FLUENT软件对集合管流场特性进行了模拟分析, 结果表明, 出口集合管盲端法兰内壁面右下侧形成了漩涡流, 连续不断冲刷壁面; 漩涡强度随介质处理量的增加而增大, 当处理量为168 t/h时, 涡量值为240 s-1, 切向速度达到16 m/s。模拟计算结果与实际集合管的检测结果吻合较好。同时, 对平盖进行了防漩涡结构优化设计, 在相同工况下进行数值模拟, 结果表明,优化的平盖结构具有较好的防冲刷腐蚀作用。

The corrosion mechanism of manifold in catalytic reforming unit was studied using the corrosion theory. The results showed that high temperature sulfur corrosion appeared in lower right side of the inner wall surface of the flange of outlet manifold. As the corrosion products were loose and porous in hydrogen-rich environment, the wall was scoured at high flow rate of fluid. The flow field features of manifold in catalytic reforming unit were numerically simulated and analyzed using FLUENT software. The results showed that swirl intensity increased with the flow of fluid, the vorticity of 240 s-1 for high-intensity swirl appeared in lower right side of the inner wall surface of the flange of outlet manifold when the fluid mass flow reached 168 t/h. The tangential velocity of fluid scoured wall surface reached 16 m/s. The numerical results are in good agreement with the inspection of manifold. In addition, the structural optimization design for anti-vortex of flat cover was carried out. In the same condition, using CFD software to numerical simulation, the results found that the optimized flat cover structure had well anti-corrosion effect.