新型陶瓷空气预热器开发与应用

Development and application of new ceramic air preheater

应用流体动力学模拟软件CFX对陶瓷蜂窝空气预热器进行了数值模拟和结构优化,确定烟气侧流体通道(流道)孔径为20 mm、空气侧流道孔径为15 mm的空气预热器性能最优。通过热态试验研究了新型陶瓷空气预热器的传热、阻力、密封和耐温性能,确定了陶瓷空气预热器的最佳运行工况:空气流道流速13~17 m/s,烟气流道流速10~15 m/s;换热系数26~30 W/(m^2·K);空气侧压力降300~750 Pa,烟气侧压力降200~500 Pa。在中石化某分公司400 kt/a酮苯加热炉的工业应用表明,新型陶瓷空气预热器能够实现加热炉烟气余热深度回收,突破了烟气露点腐蚀的障碍,加热炉排烟温度降至84℃,热效率提高到94.17%,投资回收期10.5个月。

The numerical simulation and structural optimization of ceramic honeycomb air preheater are carried out by hydrodynamics simulation software CFX. The results show that the performance of air preheater with 20 mm diameter of fluid channel on flue gas side and 15 mm diameter of fluid channel on air side is the best. The heat transfer, resistance, sealing and temperature resistance of the new type of ceramic air preheater are studied by thermal test. The results show that the best operating conditions of the ceramic air preheater are as follows: the velocity of the air flow passage is 13~17 m/s, the velocity of the flue gas flow passage is 10~15 m/s;the heat transfer coefficient is about 26~30 W/(m^2·K);the pressure drop of the air side is 300~750 Pa, the pressure drop of the flue gas side is 200~500 Pa. The industrial application of the furnace in a 4 MM TPY ketone benzene plant of a SINOPEC branch shows that the new air preheater can achieve flue gas waste heat deep recovery, and break through flue gas low-temperature corrosion barrier. Furnace exhaust gas temperature is reduced to 84 ℃, and thermal efficiency is increased to 94.2%. The payback period is only 10.5 months.