The idea to reduce cycle time (T), by controlling the side stream flow rate using a feedforward control model – the ideal side draw recovery arrangement (ISR) – was standard in most semicontinuous distillation studies. However, its effect particularly on ‘T’ and more broadly on the system dynamics was not clearly understood. In the current study, we compare the performance of using a modified form of ISR model with the status quo based on the criteria T and separating cost (SC) on different case studies. Results show that the modified control model performed better with a 10-20% reduction in SC while maintaining product purities. Furthermore, the side stream flow rate trajectory that minimizes SC was found by using dynamic optimization and it did not differ a lot from the trajectory generated by the modified control model. The improvement in SC was at most 2%.

在大多数半连续蒸馏研究中，通过使用前馈控制模型（理想的侧馏分回收装置（ISR））控制侧流流速来减少循环时间（T）的想法是标准的。然而，其对尤其是“ T ”以及更广泛地对系统动力学的影响尚不清楚。在当前的研究中，我们将使用改进形式的ISR模型与基于标准T的现状进行比较。并根据不同的案例研究分离成本（SC）。结果表明，改进的控制模型在保持产品纯度的同时，SC降低了10-20％，表现更好。此外，通过使用动态优化发现了使SC最小化的侧流流速轨迹，它与修改后的控制模型所产生的轨迹没有太大差异。SC的改善最多为2％。