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Abstract: In this article the optimal selection of the reboiler vessels, rectification columns and connection pipes with regard to reboiler swelling, and tray and pipe flooding is investigated. Since the reboilers are constrained by liquid swelling, while pipes and columns are constrained by flooding it is important to pair the equipment so that the vapor rate limitations are as close as possible, thus ensuring maximal equipment capacity usage. Calculations at 1 and 0.25bar pressure are performed for the standardized 1.6, 2.5, 4 and 6.3m3 reboiler vessels [Rührbehälter Basler Norm, N 253, 1977] and sieve tray rectification columns with nominal diameters ranging from 0.2 up to 0.6m. The dynamic operation of the batch distillation process having the vapor load and reflux ratio as input profiles is evaluated by formulating and solving an optimal control problem constrained by the hydraulic limitations. The open-loop optimization problem is solved using a dedicated Matlab tool – OptCon – which implements the multiple shooting strategy and the large-scale non-linear programming problem is handled by the HQP engine. [Copyright &y& Elsevier]

Crystallization is one of the most important unit operations used for the separation and purification of crystalline solid products. Appropriate design and control of the crystallization process is paramount to produce crystalline products with tailor-made-properties. This paper provides an overview of selected recent developments in the modelling, monitoring and control of crystallization processes. We consider the topics discussed in this review to be enabling technologies for the development of the next generation of crystallization processes with significantly improved predictability, robustness and controllability. [ABSTRACT FROM AUTHOR]