内部热耦合对理想反应蒸馏塔动态特性的影响

Dynamic effect of internal heat integration on ideal reactive distillation column

基于理想型强放热反应蒸馏塔研究了3项内部热耦合策略对系统动态特性及可控性的影响。其中,实现反应段与提馏段间正耦合作用的措施能够有效提高系统热力学效率,但同时减弱了提馏段的传质推动力,不利于系统动态操作。为改善系统的动态特性及可控性,需要在提馏段补充一定量的分离塔板。下移上进料位置提高了系统热力学效率,但也引入了逆耦合作用,严重影响系统动态操作,故在过程强化中应该回避。

The dynamic effect of internal heat integration strategies is explored in terms of a hypothetical ideal reactive distillation system containing a highly exothermic reaction. For the positive internal heat integration strategies between the reactive section and the stripping section, the thermodynamic efficiency can be improved. To guarantee favorable effect on dynamics and controllability of the process at the same time, several separating stages should be added to the stripping section to make necessary compensation for mass transfer driving forces. The descent of the upper feed stage improves the thermodynamic efficiency, but the negative internal heat integration is also introduced. The introduced negative internal heat integration generates serious detrimental effect to the dynamic behavior, and should be avoided in process synthesis and design.