变压吸附法提纯含氮气体中CO的模拟计算与设计

Simulation and design for purification of CO from N_2/CO gases by pressure swing adsorption

针对工业冷箱尾气中CO的回收工艺,应用Aspen-Adsim软件模拟并设计五塔七步骤的变压吸附(PSA)过程。考察床层高度和周期置换气量对产品CO纯度和收率的影响。结果表明:增加周期置换气量可提高CO的纯度,但有可能降低其收率;增加床层高度可提高CO的收率,但会降低其纯度。综合考虑得到:在保证一定纯度的条件下,可采取同时增加床层高度和周期置换气量来提高CO的收率;另外,当实际过程吸附剂劣化时,可以通过调节周期置换气量来维持CO收率。

A pressure swing adsorption（PSA） process with seven steps was designed with Aspen-Adsim software to purify CO from an industrial tail gas.The effects of bed height and volume of purge gas on the PSA performance were investigated.Results showed that with the increase of bed height,the CO recovery increased,but the CO purity decreased;on the other hand,the more the volume of purge gas,the higher the CO purity,but the less the CO recovery.Results from considering the CO purity and recovery together showed that the high CO recovery could be obtained with CO purity keeping at a certain extent if the bed height and the volume of purge gas were simultaneously increased.Besides,when adsorbent degradation happened in the actual process,the volume of purge gas was adjusted to maintain the CO recovery,thus meeting the process requirements.