非平衡级模型用于SO_2化学吸收过程的模拟

Simulation for chemical absorption of sulfur dioxide using a non-equilibrium stage model

为了将磷酸钠缓冲溶液吸收SO2的工艺工业化,对该过程建立了非平衡级模型,并对模拟烟气中SO2的吸收过程进行了模拟。利用溶液电离平衡理论结合离子活度系数的修正,对磷酸钠溶液吸收模拟烟气中的SO2气液平衡进行预测,获得非平衡级模型中的界面气液平衡常数。对直径为30mm,填料高度为0.6m的吸收塔中不同条件下磷酸钠缓冲溶液吸收模拟烟气中的SO2过程进行了预测。预测结果与模拟实验结果吻合良好。该模型可以为工艺设计及操作提供参考。

A non-equilibrium stage model was used to analyze SO_2 absorption in a sodium phosphate buffer solution to predict the absorption of SO_2 from flue gas. A thermodynamic model with a modified ion activity coefficient was used to predict the gas-liquid phase equilibrium of the SO_2 absorbed by the sodium phosphate buffer solution and the phase equilibrium constant at the interface in the non-equilibrium stage model. The SO_2 absorption from the flue gas was predicted for different conditions in a laboratory tower (0.03 m in diameter and 0.6 m in packed section height). The results compare well with experimental data so the model can be used for process design and analysis.