基于MEA/烟气CO2捕集系统的工艺模拟和吸收塔高度对模拟的影响分析

Process simulation and influence analysis of absorber height based on MEA/flue gas CO2 capture system

关键词:  MEA  再生能耗  Aspen HYSYS  吸收塔高度  CO₂捕集 

Key words:  MEA  renewable energy consumption  Aspen HYSYS  absorber height  CO₂ capture

摘要:

目的 对MEA/烟气CO₂捕集系统进行工艺模拟计算,研究分析理论塔板数和填料高度对模拟计算的影响。方法 采用Aspen HYSYS软件,对吸收塔采用不同填料高度和不同理论塔板数分别在溶液循环量为30 m³/h和40 m³/h时进行模拟计算,对CO₂捕集率、再生能耗等结果进行对比分析。结果 当吸收塔理论塔板数为20或25时,CO₂捕集率模拟值偏低。 当吸收塔理论塔板数为20时,再生能耗为采用252Y规整填料(填料高度10 m)吸收塔的1.61~1.87倍,为采用50 mm鲍尔环填料吸收塔(填料高度15 m)的1.53~1.78倍。当吸收塔理论塔板数为25时,再生能耗为采用252Y规整填料(填料高度10 m)吸收塔的1.31~1.38倍,为采用50 mm鲍尔环填料(填料高度15 m)吸收塔的1.24~1.32倍。 对于30%(w)的MEA/烟气吸收体系,252Y规整填料高度的临界值为10 m,50 mm鲍尔环填料高度的临界值为15 m；模拟再生能耗为4.10~4.31 GJ/t CO₂。结论 当吸收塔理论塔板数为20或25时,再生能耗模拟计算值偏高,Aspen HYSYS软件在能耗模拟方面适应性较差。采用Aspen HYSYS模拟计算时,建议先对吸收塔结构参数定义后再进行系统模拟,可得到相对准确的模拟计算结果。 

Abstract:

Objective By carrying out the process simulation calculation of MEA/flue gas CO₂ capture system, the influences of theoretical tray number and packing height on the simulation calculation were studied and analyzed. Methods The Aspen HYSYS software was used to simulate at different packing heights and different theoretical tray number of absorber under the solution circulation of 30 m³/h and 40 m³/h. The results of CO₂ capture rate and renewable energy consumption were compared and analyzed. Results The simulation results showed that the simulation value of CO₂ capture rate was low when the theoretical tray number was 20 or 25. When the theoretical tray number of absorber was 20, the energy consumption of renewable energy was 1.61-1.87 times as much as that of the absorption tower using 252Y structured packing (packing height 10 m), and 1.53-1.78 times as much as that of the absorption tower with 50 mm Pall ring packing (packing height 15 m). When the theoretical tray number of absorber was 25, it was 1.31-1.38 times as much as that of the absorption tower using 252Y structured packing (packing height 10 m), and 1.24-1.32 times as much as that of the absorption tower using 50 mm Pall ring packing (packing height 15 m). For 30 wt% MEA/flue gas absorption system, the critical height of 252Y structured packing was 10 m, the critical height of 50 mm Pall ring packing was 15 m. The simulated renewable energy consumption was 4.10-4.31 GJ/t CO₂. Conclusion sWhen the theoretical tray number of absorber is 20 or 25, the simulation value of renewable energy consumption is too high, and Aspen HYSYS software has poor adaptability in energy consumption simulation. When using Aspen HYSYS for simulation calculation, it is recommended to define the structure parameters of the absorber before carrying out system simulation, so that relatively accurate simulation results can be obtained.