Evaporators are integral parts of many separation processes across production industries, and they need to be well understood in order to be operated well, thereby enabling high resource-efficiency and productivity. In a previous investigation, the effects of disturbing oscillations in a two-stage evaporator system were quantified. In the current study, these oscillations were reduced through trajectory optimization using steam consumption as a temporally discretized decision variable, taking advantage of a dynamic process flowsheet model in Aspen Plus Dynamics (APD) employed as if it were a black-box model. The optimization was performed utilizing a Python-APD toolchain with the SciPy implementation of COBYLA. The optimal trajectory was able to successfully reduce the objective function value (including the product stream mass flow variance and a bang-bang penalty on the trajectory itself) to slightly less than 0.3 % of that of the nominal case, in which a time-invariant steam consumption was employed. This in turn grants opportunities to increase throughput of the process, leading to significant financial gains.

蒸发器是整个生产行业中许多分离过程不可或缺的组成部分，它们需要被很好地理解才能正常运行，从而实现高资源效率和生产率。在先前的研究中，对两级蒸发器系统中扰动振动的影响进行了量化。在当前研究中，通过使用蒸汽消耗作为时间离散决策变量的轨迹优化来减少这些振荡，并充分利用了Aspen Plus Dynamics（APD）中的动态过程流程图模型，就好像它是黑盒模型一样。使用Python-APD工具链和COBYLA的SciPy实现进行了优化。最佳轨迹能够成功地将目标函数值（包括产品流质量流量方差和轨迹本身的爆炸性惩罚）降低到名义情况的0.3％，在这种情况下，时间不变使用蒸汽消耗。反过来，这为增加流程的吞吐量提供了机会，从而带来了可观的财务收益。