干气进料温度对烷基化反应系统的影响与对策

Impact of dry gas inlet temperature on alkylation reaction system and Countermeasures

分析海南实华嘉盛化工有限公司稀乙烯制乙苯装置烷基化反应3段干气进料不均匀、各段床层温升不协调以及加热炉的热负荷过大等问题,发现主要是因干气进料温度过低所致。提出增设一台换热器,利用苯乙烯装置85℃的工艺凝液加热烃化反应干气进料的方法,将烷基化反应干气进料温度提高到70℃以上。实施改造后,烷基化反应3段干气能够均匀分布,床层温升基本协调;循环苯加热炉的负荷明显降低,燃料气用量降低了174.33m3/h;装置单位苯乙烯产品综合能耗降低了815.98 MJ/t,每年可节约燃料气成本279×104RMB$。

The analysis of three un-uniform dry gas feedings for alkylation reaction in ethylbenzene unit using dilute ethylene,the coordination of temperature rises of different beds and excessive thermal load of furnace and other problems has found that theses problems are mainly caused by the too low temperature of dry gas feed.It is suggested to add a heat exchanger and heat the reactor dry gas feed with 85 ℃ process condensate from styrene unit to raise the alkylation feed temperature to 70 ℃ or higher.After taking these measures,three dry gas feedings for alkylation reactions are evenly distributed,the bed temperature rise is consistent,the load of recycle benzene furnace is significantly reduced,the fuel gas consumption of recycle benzene furnace is reduced by 174.33 m3/h,the energy consumption of unit styrene product is lowered by 815.98 MJ/t benzene ethylene,and the annual cost savings is 3,055,800 Yuan （RMB）.