变压吸附制氧过程传质特性数值分析

Numerical analysis of mass transfer characteristics during pressure swing adsorption oxygen production process

研究了变压吸附制氧过程中吸附时间对制氧性能的影响,提出了利用浓度波传递模型分析变压吸附制氧过程传质特性、计算最佳吸附时间的方法。结果表明,吸附过程中吸附床内氮气浓度波形状随着时间和轴向位置而变化,理想传热传质条件下,氮气浓度波传递速度比实际吸附过程浓度波传递速度快,实际过程中由于传质和传热阻力,浓度波传递速度减少26%。基于浓度波传递模型计算的最佳吸附时间与实验值误差在0.5 s以内。

The effect of adsorption time on the performance of pressure swing adsorption(PSA)oxygen production process was experimentally investigated and a concentration wave model was proposed for analyzing the mass transfer characteristics and calculating the optimal adsorption time during the PSA process.The results showed that the shape of N 2 loading profile at adsorption step changed with time and axial position,and the propagation velocity of the N 2 concentration wave with ideal conditions was greater than the practical propagation velocity.The limited heat and mass transfer resistance slowed down the propagation of the concentration wave during the practical adsorption process,and the reduction degree of the concentration wave velocity was about 26%.The errors between the optimal adsorption time calculated though the concentration wave model and the experimental adsorption time were within 0.5 s.